Biogeochemical cycling through the Neoproterozoic

Biogeochemical cycling through the Neoproterozoic-Cambrian transition in China: an integrated study of redox-sensitive elements Ph.D.-Thesis by Lawrence Och Supervised by Dr. Graham A. Shields-Zhou and Prof. John McArthur University College London (UCL) Department of Earth Sciences April 5, 2011

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I, Lawrence Och confirm that the work presented in this thesis is my own. Where information has been derived from other sources, I conform that this has been indicated in the thesis.

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Abstract I investigated changes in the biogeochemical cycling the Precambrian-Cambrian transition on the Yangtze Platform in South China by analyzing about 350 predominantly black shale samples from several sedimentary successions deposited during the interval from the Late Cryogenian to the Lower Cambrian. I focused on redox-sensitive trace-metal concentrations in these sediments deposited under anoxic conditions whereby special attention is paid to molybdenum, vanadium and uranium to try to pinpoint the onset of increasing atmospheric oxygen levels and the transition from possibly widespread euxinia to a pervasively oxygenated deep ocean. The measurements have been carried out using X-ray fluorescence analysis (XRF) and inductively coupled plasma mass spectrometry (ICP-MS). Besides that, total organic carbon and total sulfur contents have been measured for all samples. This approach is completed by iron speciation analysis which is considered to be a reliable redox proxy. I also conducted extended literature research on trace-metal enrichment in anoxic sediments throughout Earth history as well as a major review (which will be included as an extended introduction) on all currently available lines of evidence for a major Neoproterozoic Oxygenation Event including carbon, sulphur, strontium, molybdenum and chromium isotope studies. I show that the well preserved sedimentary succession from the Precambrian-Cambrian transition on the Yangtze Platform might represent a unique archive of ancient geochemical conditions on the Earth’s surface based on a significant increase of Mo, V and U enrichment in black shales across the Pc-C boundary. The evidence for predominantly anoxic-ferruginous and even intermittently euxinic conditions in the water column across the Pc-C boundary and significant regional variations in geochemical parameters unravel complex interactions between ocean chemistry, platformal configuration and paleontology

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Contents Outline

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1. Introduction

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1.1.

The oxygenation of the Earth’s surface: an overview of the last 4 billion years

1.2.

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Tectonics and climate during the Neoproterozoic - Cambrian transition

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1.2.1. Tectonic reorganization from the mid-Neoproterozoic to Early Cambrian (825 - 530 Ma)

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1.2.2. Climatic shifts in the Neoproterozoic 750 – 580 Ma

1.3.

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Biological innovations during the Neoproterozoic – Cambrian interval

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1.3.1. The origin of life on Earth, the advent of photosynthesis and the animal revolution

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1.3.2. The oxygen requirements of early animals

1.4.

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Isotopic evidence in support of the Neoproterozoic Oxygenation Event

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1.4.1. Carbon isotopes

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1.4.1.1. The biogeochemical carbon cycle

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1.4.1.2.The carbon isotopic record

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1.4.1.3.The carbon isotopic record during the Neoproterozoic

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1.4.1.4.Total organic carbon content in sedimentary rocks throughout Earth’s history

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1.4.2. Strontium isotopes

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1.4.2.1.The 87Sr/86Sr ratio of the ocean 1.4.2.2.Changes in the seawater

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Sr/86Sr ratio during the Neoproterozoic 4

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1.4.3. Sulphur isotopes

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1.4.3.1.The sedimentary sulphur cycle

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1.4.3.2.Sulphur isotope fractionation

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1.4.3.3.The sedimentary sulphur isotope record

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1.4.3.4.The sulphur isotopic record during the Precambrian

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1.4.3.5.Temporal changes in total sulphur and pyrite content in sedimentary rocks

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1.4.4. Chromium isotopes

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1.4.5. Molybdenum isotopes

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1.5.

Rare Earth Element (REE) patterns as paleoredox proxies: the cerium anomaly

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2. Redox-sensitive trace-metals and iron speciation 2.1.

Redox-sensitive trace metals

2.2.

The redox-sensitive trace metals Mo, V and U as paleoredox

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proxies for the Neoproterozoic - Cambrian transition

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2.2.1. Uranium

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2.2.2. Molybdenum

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2.2.3. Vanadium

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2.2.4. Other trace-elements and biological productivity

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2.3.

Iron speciation: A proxy for the oxygenation of the deep ocean

2.4.

Redox-sensitive trace-metals and iron speciation in black shales on the Yangtze Platform

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3. Geological setting 3.1.

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The geological evolution of the Yangtze Platform during the Neoproterozoic and Early Cambrian 5

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3.2.

The Cryogenian

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3.2.1. The Datangpo Formation

3.3.

The Ediacaran

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3.3.1. The Doushantuo Formation (ca. 635 – 551 Ma)

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3.3.2. The Dengying and Liuchapo formation (ca. 551 – 542 Ma)

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3.4.

3.5.

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The Early Cambrian

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3.4.1. The Zhujiaqing Formation (ca. 542 – 526 Ma)

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3.4.2. The Niutitang Formation (ca. 542 – 520? Ma)

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3.4.3. The Jiumenchong Formation (ca. 542 – 520? Ma)

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3.4.4. The Yanjiahe and Shuijingtuo formations (ca. 542 – 521 Ma)

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The Xiaotan section: probably the best Precambrian – Cambrian succession in the world!

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4. Materials and Methods

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4.1.

Instrumental analysis

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4.1.1. X-ray fluorescence spectrometry (XRF)

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4.1.2. Inductively coupled plasma mass spectrometry (ICP-MS)

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4.1.3. Laser Ablation ICP-MS (LA-ICP-MS)

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4.2.

A comparison between XRF and ICP-MS analytical results

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4.3.

Iron speciation analysis

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4.3.1. The procedure

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4.3.2. Comparing total iron measurements (XRF and AAS)

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4.4.

Carbon and sulphur analysis

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4.4.1. C/S analyser

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4.4.2. Sulphide isotopes

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4.5.

Trace-metal normalisation

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5. Results and interpretation of the investigated sections 5.1.

The Cryogenian

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5.1.1. The Datangpo Formation: a profile from the manganese mine at Changxingpo, Guizhou Province

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5.1.2. Discussion

5.2.

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The Ediacaran and Precambrian – Cambrian boundary sections

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5.2.1. The Maoshi section, Guizhou Province: A Doushantuo/Dengying boundary succession

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5.2.2. The geochemistry of the Doushantuo Formation in the Three Gorges Area, Hubei Province

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5.2.2.1.Member II of the Doushantuo Formation at Jiulongwan

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5.2.2.2.The Miaohe Member (Mb. IV) at Jiulongwan

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5.2.2.3.Member II and the Miaohe Member at Jijiawan

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5.2.3. Ocean chemistry and platform evolution in the Ediacaran

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5.2.4. A high-resolution profile from the top of the Miaohe Member at Jiulongwan

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5.2.4.1.Results

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5.2.4.2.Discussion

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5.2.5. The Miaohe Member at Baiguoyuan, Hubei Province: A comparison

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5.2.5.1.Results

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5.2.5.2.Discussion

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5.2.6. The Dengying and Liuchapo formations

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5.2.6.1.The geochemical profile at Wuhe (Shibantan Mb. of the Dengying Fm.)

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5.2.6.2.The Huanglian section (Liuchapo and Jiumenchong formations)

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5.2.6.3.The Longbizui section (Liuchapo and Jiumenchong formations)

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5.2.6.4.Discussion

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5.3.

The Early Cambrian

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5.3.1. The Early Cambrian in the Three Gorges Area (Shuijingtuo and Yangjiahe formations)

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5.3.1.1.The redox geochemistry during the Early Cambrian at the Jijiawan section 180 5.3.1.2.The redox geochemistry during the Early Cambrian at the Wuhe section 181 5.3.1.3.Ocean chemistry and platform evolution during the Early Cambrian: The sequel

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5.3.2. The Zhongnan section (Niutitang Formation): A highly condensed succession on the platform margin

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5.3.2.1.Geochemical analysis

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5.3.2.2.Discussion

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The Phosphorite

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The Ni-Mo sulphide ore horizon

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5.3.3. The Xiaotan section

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5.3.3.1.The redox geochemistry of its black shale successions

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1st black shale (lower Shiyantou Fm.)

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2nd black shale succession (upper Shiyantou Fm.)

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3rd black shale succession and beyond (Yuanshan Fm.)

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5.3.3.2.High resolution sampling: results and discussion

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5.3.4. Other Early Cambrian sections on the southwestern platform (Yunnan Province)

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5.3.4.1.The Deze Section (Zhongyicun Fm., Dahai Mb.)

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5.3.4.2.The Meishucun Section (lower Shiyantou Fm.)

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5.3.5. Discussion: Biogeochemical cycling during the Early Cambrian on the southwestern Yangtze Platform

5.4.

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Biogeochemical cycling across the Precambrian – Cambrian transition on the Yangtze Platform: summary and global perspective

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6. Conclusions 6.1.

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The biogeochemical cycling of redox-sensitive trace-metals during the Precambrian – Cambrian transition on the Yangtze Platform

6.2.

6.3.

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A multi-proxy approach to investigate ancient paleoredox conditions

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Future challenges

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Appendices Formal acknowledgements

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Personal acknowledgements

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References

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References used for trace-metal, TOC and S compilations

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Correlation coefficients (R2) in some black shale successions

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High resolution geochemical profiles from the LA-ICP-MS analysis

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Raw elemental and isotopic data

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Supplement (CD-ROM attached at the back) Electronic version of the present PhD thesis Full LA-ICP-MS dataset

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Outline For the present study, I investigated the biogeochemical cycling of redox-sensitive trace-metals focussing on molybdenum, vanadium and uranium alongside the redox conditions during the Precambrian – Cambrian transition on the Yangtze Platform, South China, within the framework of the second great Oxygenation Event, herewith termed the Neoproterozoic Oxygenation Event. I therefore begin with an extended review of the present knowledge on the history of the Earth’s surface oxygenation, the major climatic, tectonic and biological events that occurred during the Precambrian – Cambrian transition and the lines of evidence for the Neoproterozoic Oxygenation Event, including compilations of a few key geochemical parameters involving carbon and sulphur cycling throughout Earth’s history. The second chapter focuses on redox-sensitive trace-metals and the temporal changes in the concentration of Mo, V and U in black shales and their potential to better constrain the Neoproterozoic Oxygenation Event in time. Chapter 3 intends to outline the geological context on the Yangtze Platform and presents the studied sedimentary successions before briefly introducing the analytical techniques used during the present study in chapter 4. The results and their interpretation are presented for the different localities and formations, followed by the conclusions which can be drawn for the biogeochemical evolution of the marine environment on the Yangtze Platform during the Precambrian – Cambrian transition. The generated datasets for elemental analysis and sulphide isotopes can be found in the appendix together with the used references and acknowledgements. A review on the Neoproterozoic Oxygenation Event has been accepted with minor revisions by the journal Earth Science Reviews as well as a paper on the biogeochemical cycling during the Early Cambrian on the southwestern Yangtze Platform (Precambrian Research).

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1.

Introduction

1.1.

The oxygenation of the Earth’s surface: an overview of the last 4 billion years Throughout Earth history, the content of oxygen in the atmosphere and the oceans has

played a crucial role in shaping our planet. The emergence of oxygen on the Earth’s surface and its concentration through time is strongly linked to several major changes on Earth such as tectonic reorganisation, climatic switches and biological evolution (see Fig. 1.1). On the other hand, its presence in the atmosphere and the oceans has also influenced planetary interactions between the biosphere and its environment allowing the Earth system to cross irreversible thresholds towards the modern Earth system characterised by the presence of metazoans, soil biota, more equable climates, and persistently high levels of oxygen in the oceans and atmosphere. Despite the fact that oxygen is the third most abundant element in the universe (after H and He; Anders and Grevesse, 1989) and the most abundant element by weight in the Earth’s crust (Barrow and Tipler, 1986), O2 was not or only sparsely available during most of Earth history and is expected to have risen to near present atmospheric levels for the first time towards the Neoproterozoic - Cambrian transition (Nursall, 1959; Canfield, 2005; Berner et al., 2003; Berner, 2006). However, the extent and timing of this suspected major oxygenation event is controversial as it has crucial implications for the understanding of our Earth system. The purpose of this introductory review is to present the current state of knowledge on the timing, extent and possible causes and consequences of the Neoproterozoic Oxygenation Event (NOE) based on geochemical and paleontological lines of evidence. First of all, oxygen is a major oxidant whose accumulation in the atmosphere forever changed the surface chemistry of the Earth (e.g. Cloud, 1972; Garrels et al., 1973; Holland, 1984, 1994, 2002, 2004; Canfield, 2005). In its role as an electron acceptor, oxygen is the most feasible and most energetic source for driving the metabolism and growth of advanced life (Catling et al., 2005). The development of the Earth’s surface and the evolution of life is 11

therefore a direct consequence of the appearance of the photosynthesizing cyanobacteria at least 2.7 billion years ago (e.g. Buick, 1992; Brocks et al., 1999, 2003), oxygenic photosynthesis being the only plausible oxygen producing mechanism which can sustain significant levels of O2 (e.g. Walker, 1977), i.e. the only source which can overwhelm the various sinks of oxygen such as oxidation of organic material and/or reducing gases. According to a recent review by Holland (2006), the subsequent evolution of the atmosphere and oceans can be divided into five stages, based on major changes in atmospheric O2 levels which arguably occurred during the last 3.82 Ga of Earth’s history (see Fig. 1.1). Despite the paradigmatic status of this interpretation, it must be emphasized that the timing and extent of Earth’s surface oxygenation has been subject to vigorous debate since the 1950’s and no firm consensus has been reached so far (Yamaguchi, 2005). One school postulates essentially constant atmospheric O2 levels since at least 3.8 Ga (e.g. Dimroth and Kimberley, 1976; Ohmoto, 1997; Yamaguchi, 2003; Watanabe et al., 2005; Ohmoto et al., 2006) whereas the other one, far more favoured amongst the scientific community, advocates a stepwise oxygenation of the Earth’s surface (e.g. Cloud, 1968; Walker, 1977; Holland, 1984; Kasting, 1987). The first stage, lasting from 3.85 to 2.45 Ga saw the emergence of oxygenic photosynthesis but the atmosphere and the oceans remained largely anoxic, allowing Fe(II) and Mn(II) to accumulate in seawater (Roy, 2006; Holland, 2006). However, some pockets of oxygen might have been present in the Archean ocean (Kasting, 1993; Anbar et al., 2007; Hoashi et al., 2009; Kendall et al., 2010) and Kato et al. (2006), for example, demonstrated that some Precambrian BIFs exhibit cerium depletion indicating cerium (III) oxidation in Archean seawater. The discovery of significant mass-independent fractionation (MIF) of sulphur isotopes in sulphides and sulphates before and during the GOE interval suggest that the O2 concentration in the atmosphere was generally less than 10-5 present atmospheric level (PAL) before c. 2.4 Ga (Farquhar et al., 2000; Farquhar and Wing, 2003; Bekker et al., 2004; Kasting et al., 2001; Pavlov and Kasting, 2002), with possibly elevated concentrations between 3.0 and 2.8 Ga (Watanabe et al., 2005) which has been related to the first known ice age at around 2.9 Ga (Young et al., 1998; Kasting and Ono, 2006).

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Figure 1.1: A) Proposed reconstruction of the atmospheric O2 content through time expressed as the percentage of present atmospheric level of oxygen (after Canfield, 2005, with Phanerozoic estimates from Berner et al., 2003). Note that the uncertainty is quite high (see text). B) Periods of supercontinent formation (modified after Campbell and Allen, 2008). C) Precambrian glaciations whereby the numbered blue bars are of presumably global extent: 1) Gaskiers glaciation, 2) Marinoan glaciation, 3) Sturtian glaciation, 4) Makganyene/Huronian glaciation. The thickness of the Neoproterozoic glaciations correspond to their duration (e.g. Halverson et al., 2005, 2007); Archean and Paleoproterozoic glaciations with unknown duration are shown with dashed lines (Evans, 2003a and references therein; Reddy and Evans, 2009). The duration of the icehouse periods in the Phanerozoic are by Veizer et al. (2000). D) Biological innovations exemplified through increase of maximum size of organisms throughout Earth history. Red dots: prokaryotes, orange diamonds: protists, brown square: vendobiont (probable multicellular eukaryote, e.g. Dickinsonia), blue squares: animals, green line: vascular plants (modified after Payne et al., 2009).

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The persistence of very low oxygen levels prior to 2.45 Ga, despite the establishment of oxygenic photosynthesis at least 300 My earlier, may be explained by the flux of reducing volcanic gases from submarine volcanoes (H2, H2S) which scavenged available oxygen (Kasting et al., 1993; Sleep and Zahnle, 2001; Holland, 2002; Li and Lee, 2004; Kump and Barley, 2007). At the Archean-Proterozoic boundary, continents became larger and more stable, resulting in volcanoes on land being more common with eruptions dominated by more oxidized gases (e.g. CO2), thus decreasing the reducing power on the Earth’s surface environment (Kump and Barley, 2007; Reddy and Evans, 2009). A recent model by Holland (2009) attributes the gradual increase in the oxidation state of the atmosphere to an increase in the CO 2/H2O and/or the SO2/H2O ratio of volcanic gases due to a greater portion of recycled gasses in the volcanic mix resulting from the subduction of carbonates, evaporites and sulphides, not or less active earlier in Earth history (see chapter 1.2.1.). A further possible reason for the delay could be that the nitrogen cycle, which would have been extended by involving nitrification and denitrification reactions after the emergence of oxygenic photosynthesis, exerted a negative feedback on the oxygenation of the atmosphere and ocean because coupled nitrification and denitrification drove the loss of fixed inorganic nitrogen, leading to nitrogen limitation which limited the growth of oxygen-producing organisms (Fennel et al., 2005; Falkowski and Godfrey, 2008; Godfrey and Falkowski, 2009). However, despite rampant but intriguing speculations, the question of what triggered the initial rise of oxygen to significant levels is still surrounded by much uncertainty. The second stage, the irreversible appearance of atmospheric O2, commonly referred to as the Great Oxygenation Event (GOE; see Table 1.2), occurred between 2.4 and 2.0 Ga (e.g. Bekker et al., 2004), during an episode of major tectonic, climatic and biological upheaval (see Fig. 1.1 and Table 1.1; Kirschvink et al., 2000; Barley et al., 2005; Reddy and Evans, 2009). The GOE led to major changes in the biogeochemical cycling of most elements which represent key factors in Earth’s surface chemistry, most importantly iron, carbon, sulphur and phosphorus and led to a diversification of mineral types (e.g. Groves et al., 2005; Hazen et al., 2008; Sverjensky and Lee, 2010). Increasing oxygen levels likely led to the extensive deposition of banded iron formations (see Fig. 1.2a; e.g. Isley and Abbott, 1999) and the more modest

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deposition of manganese deposits in shallow marine environments (see Fig. 1.2b; Roy, 1997, 2006; Maynard, 2010).

The emergence of significant amounts of O2 in the atmosphere

coincides with the ending of continuous precipitation of BIFs ca. 2.4 Ga, indicating that the cessation of BIF deposition, representing a large sink for oxygen, effectively sustained long term accumulation of atmospheric O2 (e.g. Holland, 2006). BIFs only reappear in the Paleoproterozoic towards the end of the GOE, between 2.0 and 1.8 Ga (Isley and Abbott, 1999), leading to the possibility that oxygen levels significantly decreased again to as low as 0.1% PAL in the meantime (Holland, 2004; Canfield, 2005). An increase in the weight ratio of Fe 2O3/FeO also indicates major changes in the redox state of Fe during the GOE (Yamaguchi, 2002; Bekker et al., 2003). Large positive excursions of δ13C between 2.3 and 2.0 Ga suggest that the carbon cycle was not in steady state and implies increased carbon burial which might have enhanced the oxygenation of the Earth’s surface (Des Marais et al., 1992; Karhu, 1993; Karhu and Holland, 1996; Melezhik et al., 1999b; Schidlowski, 2001). Furthermore, the first evaporitic sediments containing sulphates indicate that the concentration of SO42- in seawater increased (Strauss, 2004; Melezhik et al., 2005c; Gellatly and Lyons, 2005; Farquhar et al., 2010b), a conclusion which is also supported through the analysis of sulphur isotopes, notably by an increase in S isotope fractionation between coeval sulphates and sulphides (Δ34S; e.g. Bekker et al., 2004, Canfield, 2005). The period of the GOE also saw the first marine phosphorite deposits (Cook and Shergold, 1986, Nothold and Sheldon, 1986; Papineau, 2010). The mechanism behind widespread phosphate concretions and phosphorite deposition during the GOE is not only linked to organic matter that carries phosphate concentrated by biological activity (Knudsen and Gunter, 2002) but perhaps also to a major change in diagenetic mineralization of organic matter due to increased diagenetic sulphate reduction promoted by an overlying sulphate enriched ocean (Canfield and Raiswell, 1999) which in turn would have elevated the concentration of interstitial phosphate (Melezhik et al., 2005c). The level of atmospheric oxygen during the GOE is rather uncertain but certainly increased considerably from the beginning to the end of this period, presumably within the broad range of 0.1% to 15% PAL (Yang and Holland, 2003; Holland, 2006), or perhaps even as high as today’s oxygen levels

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(Beukes et al., 2002); both estimates are based on interpretations of the 2.2 Hekpoort paleosol of the Transvaal Supergroup, South Africa.

Table 1.1: Major tectonic, climatic and biological events during the major steps in the oxygenation of the Earth’s surface.

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Great Oxygenation Event (2.4-2.0 Ga)

Neoproterozoic Oxygenation Event (0.8-0.5 Ga)

Tectonics: Break-up of a possible Neoarchean supercontinent Break-up of the supercontinent Rodinia (>825 Ma) and (Heaman, 1997; Aspler and Chiarenzelli, 1998; the subsequent amalgamation of the supercontinent Buchan et al., 1998; Bleeker, 2003; Reddy and Gondwana (Dalziel, 1991; 1997; Evans,

2009)

and

the

formation

of

Moores, 1991;

the Hoffman, 1991; Meert and Torsvik, 2003; Meert, 2003;

supercontinent Nuna (1.9-1.8 Ga; Hoffman, 1997; Boger and Miller, 2004; Veevers, 2004; Collins and Rogers and Santosh, 2002; Zhao et al., 2002, 2004; Pisarevsky, 2005; Li et al., 2008b; Pisarevsky et al., Campbell and Allen, 2008; Reddy and Evans, 2008). 2009). Climate: Low latitude glaciations, commonly referred to as Widespread low-latitude glaciations whereby the the Makganyene and/or Huronian glaciation, and Sturtian (0.55; Raiswell et al., 1988) almost invariably record euxinia, such environments can also yield values spanning from high to intermediate due to an overestimation of the reactive iron extracted by boiling, concentrated HCl, i.e. the dissolution of silicate-bound iron which is not reactive to H2S (Canfield et al., 1992; Lyons and Severmann, 2006). Therefore, methods to define and quantify reactive iron more precisely have been developed (see review by Lyons and Severmann, 2006), notably iron speciation. The iron speciation scheme identifies seven operationally derived iron pools (Poulton and Canfield, 2005): (1) carbonate associated Fe (Fecarb), including siderite and ankerite; (2) easily reducible oxides (Feox1), including ferrihydrite and lepidocrite; (3) reducible oxides (Fe ox2), including goethite, hematite and akaganéite; (4) magnetite (Femag); (5) poorly reactive sheet silicate Fe (FePRS); (6) pyrite Fe (Fepy); and (7) unreactive silicate Fe (FeU). Iron species which are highly reactive towards dissolved sulphide (FeHR) include Fepy, Femag, Feox and Fecarb and in contrast to the DOP, excludes poorly reactive iron. The ratio Fe HR/FeT has been applied to 96

modern (Canfield et al., 1996; Raiswell and Canfield, 1996, 1998), Phanerozoic (Raiswell et al., 2001; Poulton and Raiswell, 2002), Proterozoic (Shen et al., 2002, 2003; Poulton et al., 2004a; Canfield et al., 2007, 2008) and even Archean (Reinhard et al., 2009) marine sediments in order to demonstrate or infer deposition beneath an anoxic water column. The separate identification of minerals containing ferrous iron such as magnetite (Fe mag), siderite and ankerite (as part of Fecarb), because they are likely to be ‘highly reactive’ towards dissolved sulphide (Canfield and Berner, 1987) and may occur in elevated concentrations in marine sediments deposited beneath an Fe(II)-containing water column, the iron speciation scheme could distinguish between anoxic Fe(II) containing depositional conditions and sulphidic conditions (Poulton et al., 2004b; Poulton and Canfield, 2005). However, although high Fe HR enrichment is considered to be diagnostic for deposition beneath a sulphidic water column (Raiswell and Canfield, 1996; Wijsman et al., 2001; Lyons et al., 2003), the ratio FeHR/FeT alone cannot distinguish between a non-sulphidic, ferruginous water column and a sulphidic water column (Poulton and Canfield, 2005, 2011), which ultimately depends on the possibility of sulphate-reduction potentially inhibited by low sulphate concentrations. Hence, the FePy/FeHR ratio must be applied in combination with the FeHR/FeT ratio in order to determine whether the deposition of a given marine sediment occurred under oxic, anoxic-ferruginous or sulphidic conditions. In modern marine sediments deposited under an oxic water column, the FeHR/FeT ratio does not exceed 0.38 (Raiswell and Canfield, 1998; Canfield et al., 2008). A higher proportion of highly reactive iron would indicate an anoxic water column whereby a Fe Py/FeHR ratio exceeding 0.8 characterizes sulphidic bottom waters (Canfield et al., 2008). However, the Phanerozoic average in FeHR/FeT for oxic deposition is 0.14±0.08 (Poulton and Raiswell, 2002), hence, ancient marine sediments such as of Neoproterozoic age may as well display lower FeHR/FeT ratios although bottom waters were anoxic (Canfield et al., 2007). Also, due to pyrite oxidation, a FePy/FeHR ratio down to 0.7 would still not exclude sulphidic conditions (März et al., 2008; Poulton and Canfield, 2011). The highly reactive iron cycle is composed of several sources including riverine, glacial and hydrothermal fluxes, coastal erosion, atmospheric dust and diagenetic recycling whereby the largest fraction remains in estuaries, much of it gets deposited into shelf sediments and

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finally deep sea sediments (Fig. 2.6; Poulton and Raiswell, 2002; Raiswell, 2006, and references therein). This shelf-to-basin iron shuttle is the main mechanism leading to iron sequestration and fixation under an anoxic or euxinic water column, the latter being characterized by syngenetic pyrite formation (Canfield et al., 1996; Wijsman et al., 2001; Lyons et al., 2003; Raiswell and Anderson, 2005), whereby enhanced reactivity of the detrital iron pool has also been suggested (Anderson and Raiswell, 2004).

Figure 2.6: The global highly reactive iron cycle with modern fluxes in Tg year -1(Raiswell, 2006).

The oxygenation of the deep ocean inferred by iron speciation analysis carried out in the past decade unveils an increasingly complex history. Whereas Holland (2006) essentially postulated a transition from anoxic ferruginous conditions after the GOE, the concept of Canfield (1998), who advocated a stratified ocean after the GOE with widespread sulphidic conditions, has unleashed several studies arguing for more variable conditions (see Fig. 2.7). According to Reinhard et al. (2009), episodic accumulation of oxygen in the atmosphere could have led to localized euxinic conditions in the late Archean in an ocean otherwise characterized by ferruginous conditions. After about 1.8 Ga, the transition to a possibly widely sulphidic ocean occurred concomitant with the cessation of BIF’s (Poulton et al., 2004a, 2010) and Canfield et al. (2007, 2008) presented evidence from the deep marine succession in Newfoundland that the proportion of highly reactive iron versus total iron (FeHR/FeT) decreased 98

to modern, oxic values after the Gaskiers glaciations ca. 582 Ma. However, the oxygenation of the deep ocean was not universal and bottom water chemistry might have only changed locally. And perhaps surprisingly, sulphidic conditions seem to have been rare during the late Neoproterozoic, occurring before the Sturtian glaciations and around the Precambrian – Cambrian boundary (see Fig. 2.7; Canfield et al., 2008). And last but not least, recent studies from supposedly transitional intervals in the late Archean (Reinhard et al., 2009), the Paleoproterozoic (Pufahl et al., 2010; Poulton et al., 2010) and the late Neoproteroozic (Li et al., 2010), showed that sulphidic conditions might have prevailed along continental margins above an otherwise ferruginous deep ocean, roughly analogous to modern oxygen minimum zones (see also reviews by Lyons and Gill, 2010; Poulton and Canfield, 2011).

Figure 2.7: A) shows the conception of an essentially anoxic ferruginous deep sea until after the GOE when BIF’s disappear from the geological record ~1.8 Ga and the onset of oxic conditions interrupted by a return of ferruginous conditions during the ‘Snowball Earth’ glaciations as outlined by Holland

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(2006). B) A more complex of oceanic redox states which became apparent after the concept of Canfield’s ocean (Canfield, 1998) showing intermittent euxinia before the last appearance of BIF’s (Reinhard et al., 2009) and the onset of widespread euxinia around 1.8 (e.g. Poulton et al., 2004), with possibly oxic intervals (Slack et al., 2007), and the return of ferruginous deep ocean waters towards the Neoproterozoic – Cambrian transition with the development of euxinia in the Cambrian (Canfield et al., 2008; Gill et al., 2011) before the deep sea got pervasively ventilated in the Phanerozoic (A + B modified after Lyons and Gill, 2010). C) Summary of the results from Canfield et al. (2008) based on iron speciation analysis of Neoproterozoic – Cambrian marine sediments.

2.4.

Redox-sensitive trace-metals and iron speciation in black shales on the Yangtze Platform Until today, most studies investigating the Neoproterozoic Oxygenation Event from an

elemental perspective, notably redox-sensitive trace-metals in black shales, have been carried out on samples collected on the Yangtze Platform. And as I pointed out earlier, the steep increase in Mo, V and U concentrations in black shales within a relatively narrow time span around the Precambrian – Cambrian boundary is exclusively reported from the Yangtze Platform and regardless of whether the environmental conditions were unique from a global point of view, the Yangtze Platform, from the shelf to the deeper basin, represents an exceptionally interesting geological archive of the changes in the biogeochemical cycling that occurred during these eventful times. Previous studies have either focussed on a few more or less isolated sections (Guo et al., 2007; Li et al., 2010) or simply included geochemical data from the Yangtze Platform into temporally and spatially very extensive geochemical studies (Scott et al., 2008; Canfield et al., 2008). The scope of the following study lies therefore on comparing several successions of mostly organic-rich marine sediments all over the Yangtze Platform deposited between ca. 663 Ma and the Early Cambrian ca. 520 Ma under different environmental conditions. The reliability of redox-sensitive trace-metals as paleoredox proxies can be expected to be particularly complicated during the Precambrian – Cambrian transition while iron speciation can be expected to better reflect prevailing redox conditions when applied with appropriate 100

care. Coincidentally, available iron speciation studies from the Precambrian – Cambrian transition have so far failed to demonstrate sulphidic conditions elsewhere than on the Yangtze Platform (Canfield et al., 2008; Li et al., 2010), which adds to the special interest in conducting a geographically extensive investigation on the geochemical characteristics of marine sedimentation across the platform.

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3.

Geological setting

3.1.

The geological evolution of the Yangtze Platform during the Neoproterozoic and Early Cambrian The Neoproterozoic sedimentary successions of the Yangtze platform were greatly

influenced by the tectonic history of the South China craton, one of three major tectonic cratons in China (see Fig. 3.1). The South China craton consists of the Yangtze and the Cathaysia block which have previously been thought to have amalgamated during the formation of the Jiangnan fold belt (or Sibao-Jinning orogeny) at around 900 Ma as part of the Grenvillian orogenic belt (Li et al., 1995, 2002, 2003b; 2005). However, others have advocated a younger age (ca. 800 Ma: Zhou et al., 2002a, b, 2004b) and Zhao et al. (2011) have recently demonstrated that the Jiangnan fold belt is not a Grenvillian feature and that the Yangtze and Cathaysia blocks amalgamated not earlier than ca. 830 Ma. Within a similar time span, during the break-up of Rodinia, a plume-centre was located under South China inducing widespread granite intrusions around the Yangtze block (Li et al., 1999b, 2003a), such as the 819±7 Ma Huangling Granite in the Three Gorges Area (Ma et al., 1984), and major rifting basins were formed along the southeastern and western margins of the South China craton (Li et al., 2003b; Wang and Li, 2003). The subsequent thermal subsidence created the necessary accommodation space for the Neoproterozoic sediments which unconformably overlie Mesoproterozoic metamorphic rocks or early Neoproterozoic rift-related bimodal magmatic rocks and reflect the different rifting phases (Wang and Li, 2003). The Ediacaran Yangtze platform (see Fig. 3.1) developed over a Neoproterozoic rifted continental margin presumably initiated along the southeastern side of the Yangtze block ~ 800 Ma (Li et al., 1999b; Wang and Li, 2003; Jiang et al., 2003b, 2006a). Whereas the Cryogenian successions were deposited during this rifting-drifting event, the post-glacial Ediacaran carbonate rocks were presumably deposited in a passive margin setting, although the timing of the rift to post-rift transition is still unclear (Wang and Mo, 1995; Jiang et al., 2003b; Wang and Li, 2003; Zheng et al., 2004).

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However, the Neoproterozoic sedimentary successions of the Yangtze platform, which despite the complex tectonic history of China remained relatively undeformed, can be subdivided into three main intervals: pre-glacial predominantly volcano-siliciclastic rocks (e.g. the ~750 Ma Liantuo Formation in the platform and the Banxi Group in the basin), two Cyogenian glacial diamictite intervals (the Gucheng/Tiesiao/Chang’an formations and the Nantuo Formation) separated by an interglacial unit (the Datangpo/Xiangmeng formations) and post-glacial Ediacaran marine carbonates and shales (the Doushantuo Formation and the Dengying/Liuchapo formations). The present study focuses on black shale successions from the interglacial Datangpo Formation to Early Cambrian (ca. 520 Ma) which are abundant on the Yangtze Platform (see Fig. 3.1). The term black shale herewith refers to homogenous or laminated dark to black siliciclastic marine sediments with grain sizes from clay to silt fraction and elevated organic content of predominantly above 1%.

Figure 3.1: Simplified geological map of South China with the locations of the studied sections in both, the Yangtze platform and the basin (modified after Steiner et al., 2001a; Ling et al., 2007) and a simplified stratigraphic overview of the Yangtze platform (modified after Jiang et al., 2007a). The term 103

‘Protected Basin’ refers to the seafloor from the platform margin to the deepest parts of the basin. Ages between 830 and 820 Ma have been established from numerous granitoids and ultra-mafic intrusive rocks found in the metamorphosed, Early Neoproterozoic strata (Lengjiaxi/Sibao Groups) which are uncomformably overlain by the Liantuo Fm./Banxi Group constrained with ages of 748±12 Ma from the upper Liantuo Fm. (Ma et al., 1984) and 758±23 Ma (Yin et al., 2003) and 809±8.4Ma (Zhang et al., 2008a) from the upper Banxi Group. An ash bed within the lower interglacial Datangpo Fm. yielded and age of 663±4 Ma (Zhou et al., 2004a) while an age of 654±3.8 Ma has been determined for the upper (Datangpo equivalent) Xiangmeng Fm. (Zhang et al., 2008b). The deposition of the Doushantuo Fm. is well constrained by ages of 635.2±0.6Ma and 632.5±0.5 Ma from ash beds within and on top of the cap carbonates at the base of the Doushantuo Fm. (Condon et al., 2005) and 551.1±0.7Ma near the Doushantuo/Dengying boundary (Condon et al., 2005; Zhang et al., 2005). Several ages between ca. 532 and 542 have been determined in various sections covering the earliest Cambrian (see chapter 3.1.3. and review by Jiang et al., 2011).

3.2.

The Cryogenian

3.2.1. The Datangpo Formation

The Datangpo Formation represents the interglacial sedimentary succession between the two end-Cryogenian glacial diamictites, the Tiesiao Formation and the Nantuo Formation, probably equivalent to the Sturtian and Marinoan glaciations respectively which is supported by a U-Pb age taken from a tuffaceous bed at the base of the Datangpo Fm. pointing to an age of 663±4Ma (Zhou et al., 2004a). The maximum thickness of the Datangpo Fm. is about 200 m, measured at Zhailangou, Guizhou Province (Zhou et al., 2004a), which is near our studied section in the Changxingpo mine (see Fig. 3.2). The transition from the underlying Tiesiao diamictite is relatively sharp, although the uppermost Tiesiao Fm. consists of more fine grained material. The boundary between the Tiesiao and the Datangpo formations is indicated by a dmthick finely laminated brownish mudstone. The base of the Datangpo Fm. consists of a succession of dark coloured manganese carbonate with varying thickness which was around 2 m in the area around Changxingpo Mine, where the sampling has been carried out, and about 6 104

m at Zhailanggou (Chen et al., 2008), Xiangtan (Liu, 1990, Liu et al., 2006), and Minle (Tang and Liu, 1999; Feng et al., 2010), all in Hunan Province. At the Shitang mine, about 80 km north west of Changxingpo, the Mn carbonates occur in lenses with a maximum thickness of 1.3 m above a ca. 2 m thick pyrite-rich succession of black shales overlying cross-bedded sandstone which possibly belong to the Tiesiao Fm. The base of the Datangpo Fm. at the Yuxin mine, close to Shitang, is again different: sandstones are followed by black shales (similar in Shitang) but the 1.5 m thick Mn carbonate succession is halfway interrupted by a 20 cm thick bed of friable, organic rich black shale. Black shales also overly the Mn carbonates here.

Figure 3.2: A transect across the Changxingpo Mine at the sampling site with organic rich Mncarbonates of the interglacial Datangpo Fm. overlying the glacial deposits of the Tiesiao Fm.

3.3.

The Ediacaran

3.3.1. The Doushantuo Formation (ca. 635 – 551 Ma)

The Doushantuo Fm. is probably amongst the most extensively studied Neoproterozoic formations worldwide, notably because it has yielded the richest fossil record of this crucial 105

time period, including acritarchs, algae, macroscopic bilaterians and fossil embryos (Xiao et al., 1998; Zhang et al., 1998; Xiao and Knoll, 2000; Chen et al., 2000, 2003; Condon et al., 2005; Jiang et al., 2006a, 2007a; Ling et al., 2007; McFadden et al., 2008; Ohno et al., 2008; Bristow et al., 2009). Overlying the glacial diamictites of the Nantuo Fm., the cap carbonate of the Doushantuo Fm. records the end of the Marinoan ‘Snowball Earth’ glaciation (Hoffman et al., 1998). Based on U-Pb age constraints and, most importantly, an extremely negative δ13C excursion of arguable duration between 580 and 550 Ma, the Doushantuo Fm. has been correlated with the Johnnie Formation of the Death Valley (USA), the Krol Formation in the Lesser Himalayas (India), the Wonoka Formation of the Adelaide rift complex (AUS), the Shuram Formation in Oman, the post-Marinoan Windermere Supergroup (USA), the Nama and Tsumeb groups of Namibia and in the Neoproterozoic of SE Siberia (Le Guerroué et al., 2006a; Zhou and Xiao, 2007; Jiang et al., 2008). Although the Doushantuo Formation was deposited between 635 and 551 Ma (Condon et al., 2005), covering about 90% of the Ediacaran Period, it does not exceed a thickness of about 320 m (Vernhet, 2007, and references therein). Whether it reflects a very condensed succession or contains large undetected hiatuses is presently unclear, the former being more likely (Zhou et al., 2007). Vernhet (2007) identified three different depositional environments in a study of several sections in the Chinese provinces Hunan, Guizhou and Hubei spanning shallow-water subtidal shelf environment over intertidal or shoals environment to deep-water basins, illustrating the wide bathymetric range under which the sedimentation of the Doushantuo Fm. took place on the Yangtze platform (see Fig. 3.4; see also Jiang et al., 2003b; Vernhet and Reijmer, 2010; Jiang et al., 2011). In the Yangtze Gorges area, the type locality of the Ediacaran (Sinian) system in China (Lee and Chao, 1924), the Doushantuo Fm. can be broadly subdivided into four lithological members (Wang et al., 1998). Member I consists of cap carbonates which extend throughout the central and southern Yangtze platform. They are characterized by tepee-like structures, sheet cracks, macropeloids, barite crystal fans, and negative δ13C values (Jiang et al., 2003a, 2006a; Zhou et al., 2004a). A U-Pb age of 635.2±0.6 Ma has been determined from an ash layer within the cap carbonate (Condon et al., 2005). In the Three Gorges area, the cap carbonates

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have a thickness of about 5 m and are thus relatively thin compared to other basal Ediacaran cap carbonates around the world (Hoffman et al., 2007). The overlying second member is between 80 and 140 m thick and is composed of organic-rich calcareous mudstone, thin bedded dolomicrite and interbedded black shales. An ash layer dating from 632.5±0.5 Ma is situated a few meters above the cap carbonate (Condon et al., 2005; cp. Zhang et al., 2005: 621±7 Ma). Abundant centimetre-sized chert nodules, although decreasing up-section, occur in the lower-middle part of member II and contain numerous acanthomorphic acritarchs and multicellular algae (Zhang et al., 1998; Yin et al., 2007; Zhou et al., 2007). The sparse sedimentary

structures

include

parallel

laminations,

crinkle

laminations

and

rare

intraformational breccias indicate that wave and current activity were probably absent during the sedimentation of member II (Zhou et al., 2007). Member III is between 30 and 60 m thick and composed of medium to thick-bedded dolomite with thin chert horizons and irregular chert nodules that grade up section into thinbedded limestone and dolomite interbeds (i.e. ribbon rocks). Although most chert layers are late diagenetic in origin, some of them contain very well preserved microfossils (Zhang et al., 1998; Xiao, 2004). Sedimentary structures include scour marks, crinkle laminations, low angle cross-bedding, and sandy layers capping limestone and dolomite bedding surfaces are common, indicating that deposition occurred under water depths shallower than the underlying Member II, possibly in shallow subtidal environments (Zhou et al., 2007). Member IV, commonly referred to as the Miaohe Member, is again a succession of black shales and organic-rich mudstone. Sedimentary structures are absent apart from the fine lamination and abundant, sometimes huge (⌀>1m), carbonate concretions. Pyrite and barite are also common features of this member. An ash bed on the top of the Miaohe Member has been dated and yields a U-Pb age of 551.1±0.7 Ma (Condon et al., 2005). We studied the Doushantuo Fm., or parts of it, at several locations on the Yangtze platform: Jiulongwan and Jijiawan in the Yangtze Gorges area, Hubei Province (see Fig. 3.5), and Maoshi (see Fig. 3.6; northwest of Zunyi, Guizhou Province) At the section visited at Jiulongwan a substantial part of Member II has been sampled from right above the cap carbonate throughout a discontinuously exposed succession of 107

massive grey dolomite beds with interbedded black shales (see Fig. 3.5a). Further outcrops sampled around Jiulongwan comprise the more than 10 m thick Miaohe Member (see Fig. 2.2b), consisting of laminated black shales, barite and abundant huge carbonate nodules which lie between Member III and the wavy, shaly horizon with a pyrite rich layer which constitutes the contact to the overlying Dengying Fm. Below the Miaohe Member, the top of Member III consists of dark grey dolomite which grade downwards into paler banded carbonates (ribbon rocks) followed by a sequence of yellow-brownish sandy siltstones and then again dolomite beds with some intercalated chert beds. No boundary between the Doushantuo Member II and III could be located in this region. At the Jijiawan section, the lower black shales of the Doushantuo Member II and the black shales of the Miaohe have been investigated. Member III was heavily tectonized and the top consisted of massive dolomites without apparent bedding while the lower part of the black shales of the Miaohe Mb. were slightly weathered and rather brittle (see Fig. 3.5c). The outcrop of the Doushantuo Fm. including the transition to the overlying Dengying Fm. we visited at the Maoshi section, Guizhou Province, was presumably deposited in an intrashelf basin and consisted of carbonate-rich black shales which correlate with the Miaohe Member (see Fig. 3.5 and 3.6) and an about 1 m-thick succession of organic-poor sandy shales on top underneath the dark carbonates of the Dengying Fm. This black shale member at the top of the Doushantuo Fm. occurs in almost all paleoenvironments of the Yangtze platform and marks the base of a new sequence and marine transgression (Zhu et al., 2003). And, like the cap carbonates, can be used as a stratigraphic marker. However, due the high lithostratigraphic variability of the Doushantuo Fm. throughout South China, it is unclear to what extent the subdivision into four members can be applied away from the southern limb of the Huangling anticline in the Yangtze Gorges area (Vernhet, 2007; McFadden et al., 2008). The more widely accessible Songlin section nearby Maoshi in Guizhou Province has been described to start with a 5 m-thick cap carbonate followed by 50 m of dark-grey to black shale and siltstone with some very fine-grained sandstone layers within the shales and siltstones and lenticular and nodular carbonates present within the lower half of this interval. The uppermost 30 m are composed of

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black shale, siltstone, very fine-grained sandstone, muddy silty dolomite and an increasing abundance of chert and phosphatic nodules towards the top (Jiang et al., 2008). However, in a few sections in the Hubei Province and in numerous sections in the Hunan and Guizhou Provinces, limestone units represent large scale olistoliths interbedded with thick intervals of para- to autochthonous black shales with common gravity-related sedimentary structures (Vernhet et al., 2006; Vernhet, 2007). Furthermore, phosphorite horizons occur within the Doushantuo Fm. in certain limited areas containing the Weng’an and the Miaohe biota (Li, 1986; Steiner, 1994; Ding et al., 1996; Xiao and Knoll, 2000). Although the phosphorite facies can record paleoceanographic and paleoenvironmental changes, a detailed correlation of these phosphorite horizons are questionable and therefore cause problems in determining exact ages for the Weng’an biota and other phosphorites of the Doushantuo Fm. (Li et al., 1998; Xiao et al., 1998; Zhang et al., 1998; Zhu et al., 2003).

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Figure 3.3: A) A simplified geological map of the Three Gorges Area (modified after McFadden et al., 2008). B) Approximate transaction through the sedimentary succession South of the Huangling Granite (modified after Ishikawa et al., 2008).

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Figure 3.4: The Paleoenvironmental reconstruction of the late Ediacaran platform from Vernhet (2007) is shown on the map with a possible transect across a rimmed carbonate platform as suggested by Jiang et al. (2003b).

111

Figure 3.5: A) The Doushantuo member II sampled along a road at Jiulongwan with several parts weathered away from the outcrop. B) The upper Member III and the whole Miaohe Member of the Doushantuo Fm. C) Parts of Member II and the Miaohe Member at the Jijiawan section, the boundary between Member II and III so far not been reported from Three Gorges Area. 112

Figure 3.6: The sampled Maoshi section, Guizhou Province, where the boundary between the Doushantuo and Dengying formations are exposed.

3.3.2. The Dengying and Liuchapo formation (ca. 551 – 542 Ma)

In contrast to the underlying Doushantuo Fm., a relatively short time interval, from 551 to 542 Ma, is represented by the much thicker (ca. 240-850m) Dengying Fm. which can be subdivided into three members based on their respective lithology (Zhao et al., 1988). In the Three Gorges area these are: The Hamajing Member at the base (20-190 m thick) which consists of light-grey, medium- to thick-bedded dolomite with intercalated thin chert layers, the overlying Shibantan Member (100-160m), characterized by dark grey, thin-bedded limestone and on top, the Baimatuo Member (60-570m) which is composed of light-grey, thick-bedded 113

dolomite. The algal fossil Vendotaenia antiqua, the macrofossils Paracharnia dengyingensis and Yangtziramulus zhangi, possible sponge spicules and Planolites-like trace fossils can be found in the Shibantan Member (Sun, 1986; Zhao et al., 1988; Steiner et al., 1993; Shen et al., 2009) while characteristic fossils in the Baimatuo Mb. include the Cloudina-like tubular fossil Sinotubulites baimatuoensis and several ichnogenera in its lower part (Chen et al., 1981; Zhao et al., 1988). The tripartite subdivision of the Dengying Fm. can be recognized across the platform although a different terminology is sometimes used (Ding et al., 1992; Zhu et al., 2003; Steiner et al., 2007). The following outcrops including the Dengying Fm. have been visited during this study but only little analysis has been carried out due to a general low content of sedimentary organic matter: Zhongnan (see Niutitang Fm.), Maoshi, Xiaotan (see Zhujiaqing Fm.), Jiulongwan (see Doushantuo Fm.) and Wuhe. At the Maoshi section, Guizhou Province, the base of the Dengying Fm. is a succession of alternating black carbonates, which get paler up-section, and sandy carbonates (see Fig. 3.6). At the Wuhe section (see Fig. 3.7) in the Three Gorges Area, the base of the Hamajing Mb. consists of wavy beds of massive dolomite with some tee-pee like structures which are probably slump-structures and not genuine tee-pees. The base of the Shibantan Mb. is characterized by thinly bedded limestone followed by a succession of dark, pyrite-rich, macrocrystalline limestone beds, a few intercalated chert layers and chert nodules. The top of the Shibantan Mb. is rich in chert nodules and grades into what is possibly the Baimatuo Mb. with low amplitude wavy bedding of the carbonates. The depositional environment of the Dengying Formation is interpreted as a widespread prograding platform. Oolitic textures and oncolites in the dolomitic Hamajing Member are characteristic of a high-energy environment following the black shale deposition at the top of the Doushantuo Fm., indicating a sea-level drop during the transition from the Doushantuo to the Dengying Fm. Towards the southeast, the carbonate successions become gradually condensed, ultimately changing into the slope and basinal facies of the corresponding Liuchapo Formation (see Fig. 5 in Steiner et al., 2007). The Liuchapo Fm. is mainly composed of black silicified shales of which the upper part has been sampled at Huanglian, Guizhou Province, and Longbizui, Hunan Province, both close to the provincial border at about 70 km distance from each other (see Chapter 3.1.3.). Sequence analysis of the Liuchapo Fm. suggests that the lower

114

and middle part correlate with the Hamajing and Shibantan members of the Dengying Fm., the lower part being deposited during a sea level high stand following the transgressive facies of the Miaohe Mb. of the Doushantuo Fm. and followed by a deepening upwards transgressive succession equivalent to the Shibantan Mb. (Wang et al., 1998). The trace fossils Planolites and Skolithus and the small shelly fossils Anabarites trisulcatus Protohertzina, Hyolithellus together with monoplacophorans, gastropods and chancellorides found within the upper part of the Liuchapo Fm. suggests equivalence with the lowermost Cambrian in Yunnan Province (Wang et al., 1998, and references therein) and hence, the possibility that the uppermost Liuchapo Fm. was deposited across the Precambrian – Cambrian boundary.

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Figure 3.7: The sampled succession of the Dengying Formation at Wuhe, Three Gorges Area (left). An impression of the massive cliffs representing the Dengying Fm. in the Three Gorges Area (below).

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3.4.

The Early Cambrian The Global Standard Stratotype-section and Point (GSSP) for the base of the Cambrian

system is the first appearance datum (FAD) of the trace fossil Trichophycus pedum in the Fortune Head section, Newfoundland, Canada (Brasier et al., 1994; Landing, 1994; Babcock and Peng, 2007). However, due to a lack of convincing evidence for the occurrence of the trace fossil Trichophycus pedum in Cambrian sediments in South China and convincing absolute age constraints (Compston et al., 1992, 2008; Yang et al., 1996; Jenkins et al., 2002), the Precambrian-Cambrian boundary definition focuses on the biostratigraphy of small shelly fossils (Steiner et al., 2007) and the Meishucun section (Kunyang Mine, near Kunming, Yunnan Province) has been considered as a possible Precambrian-Cambrian boundary stratotype (Cowie, 1985; Luo et al., 1992; Shields et al., 1999) although SSF’s may occur stratigraphically below Cambrian-type trace fossils (Lindsay et al., 1996), as is the case in South China.

3.4.1. The Zhujiaqing Formation (ca. 542 – 526 Ma)

The Ediacaran-Cambrian boundary interval in eastern Yunnan, which has traditionally been regarded as a good candidate for the Early Cambrian stratotype (Luo et al., 1982, 1984), can be divided into five intervals (Zhu et al., 2001; Zhu et al., 2003) spanning over three Formations, in ascending order the Zhujiaqing Fm., the Shiyantou Fm. and the Yuanshan Fm. The first interval, the Daibu Member at the base of the Zhujiaqing Fm., is composed of laminated chert with intercalations of laminated dolomite and black shales and lies between the thick-bedded dolomites of the Dengying Fm. and the first occurrence of SSF’s within the overlying phosphorites. No SSF’s have so far been recovered from the Daibu Mb. and it is therefore disputed whether it constitutes the base of the Cambrian although this assumption has been made when drawing the following stratigraphic columns. The overlying Zhongyicun Member mainly consists of phosphorite and phosphatised dolomite with abundant SSF’s. The dating of an altered bentonite layer within the Zhongyicun Mb. yielded a SHRIMP U-Pb age of 539.4±2.9 Ma (Compston et al., 2008). The Dahai Member is built up by dolomite and limestone 117

and represents the uppermost part of the Zhujiaqing Fm. The fourth interval lies between the base of the Shiyantou Fm. and the horizon indicated by the first occurrence of trilobites in the Yuanshan Fm. and the fifth interval (Qiongzhusian) comprises the two earliest trilobite zones as well as the sediments containing the Chengjiang biota (Hou et al., 1991; Babcock et al., 2001). The outlined successions above can be recognized in several sections in Yunnan and Sichuan Province and represent shallow water platform facies. Despite being devoid of significant successions of black shales, parts of the Zhujiaqing Fm. have been sampled in the Deze section (Dahai Mb., see Fig. 3.8), North of Kunming, Yunnan Province. The mining of phosphorites from the Zhongyicun Mb. around Deze, Yunnan Province, offer an excellent insight into Early Cambrian sediments and especially the Zhujiaqing Fm. The uppermost 15m of the Daibu Mb. exhibit chert beds alternating with bedded siltstone. The abundance of bedded chert increases towards the top of the Daibu Mb. before the onset of massive phosphorites of in the Zhongyicun Mb., which have mostly been excavated, leading to a well recognisable marker across the landscape. The sampled base of the Dahai Mb. (ca. 7m), overlying the massive phosphorite beds of the Zhongyicun Mb., is characterized by dolomite beds with abundant phosphate nodules, some thin phosphorite layers and a 30 cm thick shale horizon (see Fig. 3.8).

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Figure 3.8: The sampled part from the Dahai Mb. at the Deze section. The boundary between the Zhongyicun and the Dahai members lies within and uncertainty of 1-2 m.

3.4.2. The Niutitang Formation (ca. 542 – 520? Ma)

The Early Cambrian Niutitang Fm. uncomformably overlies the Dengying Fm. and its base contains stratiform chert, nodular and bedded phosphates and black shales with a very high organic content of up to 15% (Steiner et al., 2001a) representing a typical transgressive facies. A conspicuous Ni-Mo-sulphide ore horizon is intercalated with black shales in this basal part of the Niutitang Fm. and represents a characteristic feature of many Early Cambrian sections deposited in the transitional zone between the platform and basin (Coveney and Chen, 1991; Lott et al., 1999; Steiner et al., 2001a; Lehmann et al., 2007; Jiang et al., 2006b, 2007b; Wille et al., 2008; Pašava et al., 2008; Chen et al., 2009; Wen and Carignan, 2011). The upper part mainly consists of shales and black shales. The whole Niutitang formation is about 60 m thick and recognized in several sections in Guizhou and Hunan Province. We sampled the base of the Niutitang Fm. at the Zhongnan section, Guizhou Province, where a ca. 1 m-thick phosphorite layer with possibly glauconite in the lower part, represents a typical transgressional facies and sets on right above the Dengying/Niutitang unconformity (see Fig. 3.9) 119

and is followed by a ca. 20 cm-thick pyrite-rich black shale horizon which indicates the sulphide ore horizon. The overlying strata consist of black shales with very high organic carbon content.

Figure 3.9: The stratigraphy at Zhongnan where the Niutitang Fm. uncomformably overlies the Late Ediacaran Dengying Fm. (left). The photo shows how the Ni-Mo-sulphide ore layer has been mined below the hanging wall of black shales (right).

3.4.3. The Jiumenchong Formation (ca. 542 – 520? Ma)

The Early Cambrian Jiumenchong Formation is about 200m thick and represents slope to basinal sediments overlying the cherty shales and chert beds of the Late Ediacaran Liuchapo Fm. It is composed of black-greyish carbonaceous shale, mudstone and limestone. Bivalved arthropods (Sunella) and tubular fossils (Sphenothallus) have been reported from within the black shale at the lower part of the Jiumenchong Fm. while trilobites are found within the upper limestone part, including Hupeidiscus orientalis, Sinodiscus changyangensis and Metaredlichia sp. (Yang et al., 2003). The region around Huanglian is rich in outcrops but

120

stratigraphic control is complicated by tectonic deformation and heavy weathering in some parts. The uppermost 10m of the cherty shales of the Liuchapo Fm. and the first 2m of the overlying, very black shales of the Jiumenchong Fm. have been sampled at Huanglian where, in addition, two samples have been recovered from the Miaohe Mb. of the Doushantuo Fm. (see chapter 3.1.2.). The situation at Longbizui is more straightforward where the stratigraphy from the Sturtian equivalent diamictites up to the Cambrian Jiumenchong Fm. is well exposed. Sampling has been conducted across the Precambrian – Cambrian transition whereby a 1m thick, organic-rich horizon is observed within the cherty shales about 40m below the Liuchapo/Jiumenchong boundary. A succession of more massive, bedded cherts occurs just below the boundary to the Jiumenchong black shales, which continue for at least 40m upwards and include a few horizons rich in macroscopic pyrite crystals (see Fig. 3.10).

121

Figure 3.10: The Liuchapo/Jiumenchong boundary sections, equivalent to the Precambrian – Cambrian transition, at Huanglian and Longbizui, Hunan Province.

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3.4.4. The Yanjiahe and Shuijingtuo formations (ca. 542 – 521 Ma)

The Yanjiahe Fm. which covers the base of the Cambrian south of the Huangling anticline in the Three Gorges Area (see Fig. 3.2) overlies pale, massive dolomites of the Dengying Fm. (Baimatuo Mb.) above a sharp, wavy boundary. The Yanjiahe Fm. is about 35 m thick and consists of dolomitic muddy limestone, calcareous black shale and some sandstone and chert (Ishikawa et al., 2008). The above Shuijingtuo Fm. is about 100 m thick and mainly consists of black shale with many prominent carbonate nodules (Ishikawa et al., 2008). Mainly based on carbon isotope stratigraphy it is likely that the upper part of the Yanjiahe Fm. is equivalent to the Dahai Mb. of the Zhujiaqing Fm. (Zhou et al., 1997; Ishikawa et al., 2008). The sampling of the Yanjiahe and Shuijingtuo formations has been conducted at the Wuhe section (see Fig. 3.11a), where the base of the Yanjiahe Fm. is characterized by grey carbonate beds with thin chert intercalations. Abundant phosphatic cherts are observed in the middle part of the Yanjiahe Fm. whereas massive dolomite beds followed by organic-rich black dolomite interbedded with siltstone including regular shaped certified carbonate nodules occur in the upper part before the boundary to the Shuijingtuo Fm. The boundary zone is characterized by a thin (ca. 10 cm) phosphorite bed followed by a conglomeratic layer with ripped-up clasts and fromboidal pyrite crystals. The basal Shuijingtuo Fm. consists of black shales with abundant huge dolomite concretions and some intercalated grey massive dolomite beds. At the Jijiawan section (see Fig. 3.11b), sampling began within sandy dolomites of what possibly represents the lower part of the Shuijingtuo Fm. followed by dark-grey carbonates with soft, silty intercalations and then thin-bedded black shales with huge nodules and a few carbonate beds a break in the exposure of the outcrop occurs. About 10m further up in the stratigraphy, brittle black shales with abundant carbonate concretions reappear and characteristic white crystals, presumably barite, occur in between the relatively thin layers. The succession becomes sandier upwards and sandy carbonates appear at the upper tens of meters of the Shuijingtuo Fm. (inaccessible cliffs) before the onset of the greenish-brownish mudstones of the Shipai Fm.

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Figure 3.11: A) The Precambrian – Cambrian transition at Wuhe, Hubei Province. B) The Early Cambrian sedimentary successions at Jijiwan, Hubei Province. Not that the Yanjiahe – Shuijingtuo formation boundary is unclear and the sampled succession might be from the Shuijingtuo Fm. only.

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3.4.5. The Xiaotan section: probably the best Precambrian – Cambrian succession in the world! The Xiaotan section, Yunnan Province, is situated along the Jingsha River, one of the major headwater streams of the Yangtze River, and exhibits an unusually complete and expanded stratigraphic column spanning the upper part of the end-Neoproterozoic Dengying Fm. to at least the mid-Cambrian Canglangpu Fm. (see Fig. 3.12). An erosional surface separates the massive grey dolomites of the upper Dengying Fm. from the > 90m thick Daibu Mb., which is characterized by dark siliceous micritic dolomites (at the base), and chert layers and nodules, sandy dolomites and dolomite nodules (at the top). The onset of the ca. 80m thick Zhongyicun Mb. is easily recognizable by dark phosphorite beds which are less pronounced in the middle part of the member, where a U-Pb SHRIMP age of 539.4±2.9 has been reported from Meishucun section (Compston et al., 2008), but reappear in massive beds in the upper part. Furthermore, siliceous dolomites, dolomites, sandy dolomites and shales are common within the Zhongyicun Mb. The overlying Dahai Mb. consists of a lower dolomite and a thicker upper limestone part and is about 70m thick. The base is characterized by a few chert nodules and abundant dolomite nodules before a disturbed, perhaps tectonically induced, zone sets in. The undisturbed upper part is composed of massive carbonate beds reaching individual thicknesses of up to 1m. A characteristic positive δ13C excursion has been observed during the Dahai interval which can additionally be used for correlation across the platform (Zhou et al., 1997; Shen and Schidlowski, 2000; Ishikawa et al., 2008; Li et al., 2009). The contact between the Dahai Mb. and the Shiyantou Fm. is again very sharp, changing from massive carbonates, which are slightly sandy towards the boundary, to the black shales of the Shiyantou Fm. The Shiyantou Fm. overlies the Dahai Mb. after a sharp lithological change from phosphatic carbonates to siliciclastic rocks representing a clearly recognizable boundary throughout the Yangtze platform and probably represents a major tectonic event (Zhu et al., 2003). Iridium enrichment has been reported from within a metal-enriched layer close to the Dahai/Shiyantou boundary that can be interpreted to represent a maximum flooding surface with minimal sedimentation (Hsü et al., 1985; Wallis, 2006). The base of the Shiyantou Fm., 125

recognized in sections in the southwestern part of the Yangtze platform, is characterized by a thin phosphatic conglomerate followed by a thicker clay member indicating a rapid deepening event (Zhu, 1997). The overlying 100-190 m consists of a black shale succession overlain by paler siltstones which possibly represent a shoaling up sequence from suboxic into more oxic conditions (Zhu, 1997). Geochronological analysis of single zircons from a bentonite layer within tuffaceous marl at the base of the Shiyantou Fm. in the Meishucun section, Yunnan Province, yielded a U-Pb SHRIMP age of 526.5±1.1 (Compston et al., 2008). At the Xiaotan section, the base of the Shiyantou Fm. is recognised through a thin, conglomeratic, phosphate-rich layer overlying the sandy carbonates of the Dahai Mb. The following 32m consist of black shales with a few beds of laminated dolomite and dolomite concretions; some of them being septarian concretions, for which the formation mechanism is still unclear (Pratt, 2001). This black shale succession ends with a 0.5m thick layer of sandy siltstone before an 80m thick succession of paler siltstones with diverse coloration from yellowish, brownish, greenish, light grey to grey that transition into a 50m thick succession of fine-grained laminated greenish sandstone with a few visible cross stratifications. The following ca. 20m are characterized by grey calcareous sandstones with abundant siliceous nodules. The overlying 40m of black shale contains some dolomite concretions, a 2.5m thick intercalation of massive dolomite beds in the middle and more abundant dolomite concretions in the upper part. The lower part of this second black shale member contains numerous white ‘chips’ oriented parallel to the fine lamination. The overlying 40m of alternating greenish-greyish siltstones and dolomite beds with abundant elongated dolomite concretions constitutes the top of the Shiyantou Fm. This similarity to the boundary succession between the Zhujiaqing and the Shiyantou Fm. could again indicate a rapid deepening event. A profile of ca. 15m within the the lower Shiyantou black shale succession has also been sampled at Meishucun near the Kunyang Mine, Yunnan Province, starting about 5m above a thin, only locally occurring, bentonite layer between the Dahai Mb. and the Shiyantou Fm. The base of the Yuanshan Fm. consists of a third succession of thin beds of black and dark shales after a thin layer with large, rounded crystalline calcite components in finely laminated black siltstone which represents the Shiyantou/Yuanshan formation boundary ( see

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Fig. 3.12). After 27m of these black shales, follows a ca. 50m succession of more massive dark grey calcareous siltstone beds and then a 36m thick member of more massive greenish siltstones. The top 3m of the Yuanshan Fm. are characterized by irregularly laminated brownish-yellowish siltstone with some grey nodules and sandstone lenses just beneath the massive, colourful, cross-stratified sandstones of the Canglangpu Fm. It has been shown that global sea-levels rose generally throughout the Cambrian in a series of transgression-regression cycles of shorter duration (Miller et al., 2005; Haq and Schutter, 2008) which might correspond to the changes in lithology observed at Xiaotan: notably the three black shale successions interpreted as deepening events. To our knowledge, no large fossils have been discovered at Xiaotan and the known fossil record is limited to small shelly fossils (SSF’s; Li and Xiao, 2004; Steiner et al., 2007). They can be divided into up to four distinct assemblages in the Zhongyicun Member, the Dahai Member and in the upper Shiyantou/lower Yuanshan formations (see also Qian and Bengtson, 1989) where they are succeeded by the earliest record of Chinese trilobites (e.g. Steiner, 2001). Burgess shale-type fossiliferous strata occur within the Yuanshan Fm. near Kunming on the southern Yangtze Platform, and include the extraordinarily well preserved Chengjiang Biota (e.g. Babcock et al., 2001; Hagadorn, 2002), which represent the oldest fossil Lagerstätte of that type (Gaines and Droser, 2010).

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Figure 3.12: A schematic stratigraphic profile as seen at Xiaotan, Sichuan Province (left), reaching from the upper Dengying Fm. (DNG) to the Middle Cambrian Canglangpu Fm. (CLP). The sampled intervals are indicated and more details regarding sampling can be found in chapter 5.3.3. The photo below shows the boundary between the Shiyantou and Yuanshan formations at the Xiaotan section.

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4.

Materials and Methods

4.1.

Instrumental analysis

4.1.1. X-ray fluorescence spectrometry (XRF)

The basic principle of an XRF spectrometer is to use primary radiation from an X-ray tube to excite secondary (fluorescent) X-ray emission from a particular sample which includes characteristic X-ray peaks related to the corresponding major and trace elements in the sample (see Fig. 4.1; e.g. Fitton, 1997). Because characteristic X-ray peaks are superimposed on a background of radiation from the X-ray tube, the intensity of the background radiation is subtracted from the characteristic peak whereby the net intensity at each of the peak positions is calibrated against known synthetic standards and reference materials. The lower limits of detection for the elements measurable by XRF are given in Fig. 4.2. The insensitivity of X-rays to chemical bonding and valence effects allows the direct analysis of solid samples avoiding the need for dissolution or other chemical pre-treatment. However, the quantitative analysis and correction of absorption and enhancement effects of a given sample assumes that the sample is homogenous. This means that a sample has to be finely grinded in a way to minimize particle-size effects and was carried out in the present study by milling the bulk rock samples with a tungsten-carbide mill. For the analysis of trace elements, around 10 mg of sample powder has been pressed into a disc-shaped pellet using ~1 ml of a 20% araldite solution as binding agent. The only way to eliminate particle size effects completely is to homogenize the sample by fusion. However, as the added flux dilutes the sample, enhancing X-ray background levels and reducing the net intensity of the fluorescent radiation, this procedure is only applied for major elements. The procedure starts with drying about 3 g of sample powder overnight at 110°C in a glass bottle. 0.7 g of the powder is then accurately weighed into platinum crucibles and ignited at 1100°C for about 20 min covered by lids. The remaining sample is then weighed again to calculate the volatile-free sample weight. 6 times the sample weight of flux is then added (Alfa129

Aesar Spectroflux 105: Li-tetraborate, Li-carbonate and La-oxide), plus about 0.02 g extra to account for volatiles in the flux, and fused at 1100°C. Usually the flux loss on ignition exceeds the extra weight added and the weight has to be made up by adding more flux in order to approach the weight of the sample and 6 times its weight during flux fusion as closely as possibly. Following that, the mixture is again fused with Meker burners and the liquid is casted into round, flat beads, labelled and introduced into the XRF. Major and trace element concentrations in the black shale samples from the Zhongnan, Xiaotan (XT1-29), Meishucun, Huanglian, Changxingpo and Maoshi sections have been measured using a Philips PW2400 X-ray fluorescence spectrometer at the Royal Holloway University of London.

Figure 4.1: Schematic depiction of a typical XRF spectrometer. Thick lines with arrows indicate primary X-ray radiation from an X-ray tube which ionizes the sample by displacing electrons from its component atoms which in turns causes an electron from an outer shell to fill the vacancy ultimately leading to the emission of secondary (fluorescent) X-ray photons with characteristic energy and wavelength parameters of the atom. This photon will either be absorbed within the atom (especially when this atom is small) or escape and form part of the characteristic spectrum. The resulting small proportion of the generated secondary X-rays is then collimated to form a parallel beam which is 130

diffracted by a synthetic analyzing crystal and then collimated again before passing to an X-ray detector. The crystal can rotate around an axis on its surface while the secondary collimator and the detector are coupled to the crystal so that they move in an arc around the rotation axis of the crystal by twice its angular rate of rotation to keep the angle of incidence equal to the angle of reflection (θ). The Bragg equation relates the angle θ to wavelength λ: nλ = 2d sinθ, whereby n is an integer and d the lattice spacing of the crystal. After Fitton (1997).

Figure 4.2: Periodic table illustrating the elements which can be determined in geological material using X-ray fluorescence spectrometry and approximate detection limits (Fitton, 1997).

4.1.2. Inductively coupled plasma mass spectrometry (ICP-MS)

This multi-element technique consists of positive ions generated in inductively coupled plasma which are extracted, via a differentially pumped air-vacuum interface, to a lowresolution mass spectrometer (Jarvis, 1997). The sample is usually dissolved and diluted before being introduced and converted by a nebulizer into an aerosol which is then converted into large droplets by a nebulizer before attaining the plasma torch. The sample aerosol is then rapidly volatilized, dissociated and ionised. The ions are extracted by a decrease in pressure and 131

focussed using a set of lenses before entering the mass spectrometer, usually a quadrupole. The ions are then separated on the basis of their mass to charge ratio and a detector receives an ion signal proportional to their concentration. While the relatively low mass resolution of a quadrupole mass analyser is sufficient to separate adjacent elemental mass numbers, interferences from polyatomic ions might cause a problem. This particularly applies to vanadium and arsenic in the presence of chloride. Further problems might arise through refractory oxide ions where the elements with the highest oxide bond strength, including Al, Ba, Mo, P, REE, Si TI and Zr, yield the most oxide ions although rarely develop oxide abundances exceeding 1.5% (see Jarvis (1997) for a more detailed description of possible interferences). Trace element concentrations of samples from the Xiaotan (XTY1-61 and XTS1-14), Deze, Jiulongwan, Jijiawan and Wuhe sections have been measured using the solutions obtained by the total iron dissolutions (1000× dilution) carried out at Newcastle University (see chapter 4.2). These have been evaporated in order to remove the HCl and then redissolved using nitric acid. The final solution, containing 0.15ml HNO3, 0.1ml 500 ppb Rh for instrument calibration and 3.75ml H2O, was analysed by Heizhen Wei from the State Key Laboratory for Mineral Deposits Research, Nanjing University, using a Finnigan Element II ICP-MS. The precisions are generally better than 5% for the analysed elements based on long-term uncertainty of the lab measurement on standard carbonate. However, the major source of inaccuracies is sample preparation which has to be carried out with great care to avoid contamination and incomplete dissolution of the sample. Apart from that, the precision of the ICP-MS is high for most of the elements measurable (see Fig. 4.3).

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Figure 4.3: Elemental limits of detection when using an ICP-MS (after Jarvis, 1997).

4.1.3. Laser Ablation ICP-MS (LA-ICP-MS)

A continuous piece rock of about a meter length has been recovered from the top of the Doushantuo Member IV (Miaohe) at the Jiulongwan section for high resolution Laser Ablation ICP-MS analysis in order to record fine changes in the geochemistry of this laminated black shale. After transport, the brittle black shales fell apart but the original position could still be identified and seven blocks with a surface width of 2.5cm and a height of 5cm have been sawn out (see Fig. 4.4a) and scanned perpendicular to the lamination by laser ablation (Resonetics RESOlution M-50). A custom-build excimer (193 nm) laser-ablation system with two-volume laser-ablation cell coupled to a quadrupole ICP-MS (see Fig. 4.4b; Müller et al., 2008) has been used at the Royal Holloway University of London under the guidance of Christina Manning and Wolfgang Müller. The spotsize of the laser has been set to a diameter of 96 μm which ablated the rock material at a speed of 50 μm/s. The sample aerosol is then flushed out by He and led into the ICP-MS (Agilent 4500 Series) for which the procedure has been broadly outlined in chapter 4.1.2. Together with the sample, an industry standard (NIST 610) is fixed to the sample holder for reference. The output looks like in figure 4.5, where background radiation is

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measured before and after the measurement of the standard, followed by the sample analysis and again before and after the second standard measurement. The raw data can be divided in baseline, standard and sample measurement and processed by hand or by using imaging software (Woodhead et al., 2007). For the current study, the dataset has been processed by first subtracting the average background signal (baseline) from the standard and sample values of each element analysed (see appendix). The corrected standard and sample values are then normalized to previously defined silicon concentrations. In the case of the present study, SiO2 concentrations of about 70% have been assumed based on XRF measurements of similar lithologies from equivalent stratigraphic levels but elsewhere on the Yangtze Platform. Because element concentrations in our standard are known, the whole dataset can be adjusted to semi-quantitative element concentrations in each of our black shale samples. But because it is very unlikely that Si concentrations are constant throughout the sample especially not at such high resolution, the results must be treated with caution. In order to estimate possible miscalculations due to inhomogeneous distribution of Si within the sample, element mapping has been carried out on a Jeol JXA-8100 electron probe microanalyser at the UCL under the guidance of Andy Beard. Prior to analysis, thin sections of the same sample surface have been produced, finally polished and coated with pure carbon. The analysed surface measured 900*900µm with a resolution of 1µm (see Fig. 4.6).

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Figure 4.4: A) The continuous but scattered black shale interval from the top of the Miaohe Mb. (see chapter 3.1.2.) with the indicated positions of the 7 sample blocks. B) Highly schematic cross section of the Laurin two-volume laser-ablation cell (not to scale). Helium (He) enters the cell body at its bottom, and flows from both bottom and top through the funnel, where the He flow entrains the aerosol that condensed out from the laser-induced plasma. The funnel-shaped upper cell and the tilted reflected light illumination improve the off-axis viewing system. Sample aerosol and He leave the LA cell for the ICP-MS via an exit tube connected to the cell body via a ball joint (Müller et al., 2008).

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Figure 4.5: A) Shows the sample holder with the sample block and standard from above. The solid red lines indicate the laser ablation tracks. B) Output of the unprocessed data showing the total signal intensity (CPS) as the laser moves through the procedure.

Figure 4.6: A 900×900μm element map for Si carried out by an electron probe microanalyser (Jeol JXA-8100) on a black shale sample. The size of the laser beam is projected in the middle of the map and illustrates the inhomogeneities possibly leading

to

inconsistencies

when

normalizing the LA-ICP-MS signal to a single element concentration for sedimentary rocks.

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4.2.

A comparison between XRF and ICP-MS analytical results 10 samples from different sections and geochemical compositions have been measured

with both the XRF and ICP-MS techniques and although the same powders have been used, some disparity can be expected due to the different sample preparation. This particularly applies for a couple of elements which are present in barely soluble mineral phases and hence difficult to measure using ICP-MS analysis, such as barium in barite and titanium in certain silicate minerals. The samples measured by both methods and the respective results can be found in the appendix while correlation patterns are shown in figures 4.7 and 4.8. We see that there is no clear trend showing that either method over- or underestimates element concentrations in a consistent way. Sc varies significantly between XRF and ICP-MS measurements whereby the relatively low concentrations in HL14 are more than 95% higher when measured with ICP-MS. Higher concentrations exhibit less disparity but show higher XRF values in all CXP samples and KY1 of up to 38.6%. Low Ti values in HL14 are slightly overestimated by the ICP-MS but apart from that are consistently higher, up to over 57% for KY5, when measured with the XRF, indicating Ti concentrations in HL14 below detection limit and barely soluble Ti phases when abundant. V and Cr concentrations generally agree well between both methods, remaining within 20% difference except for KY1 and CXP10 (see Fig. 4.7). Mn shows huge discrepancies where the concentration is low in HL14 and XT5 but generally remains within ±20% difference in the other samples with higher Mn content. Ni varies similarly, except for CXP13 where the XRF method yields an almost 35% higher concentration. Cu is mostly underestimated by the ICP-MS, mostly in ZN4 (41% less) and CXP 13 (51% less) with respect to XRF analysis. Element concentrations in ZN samples show more than double the concentration when measured with the ICP-MS in the case of XRF values less than 20 ppm but are generally underestimated with regard to XRF measurements when higher concentrations are found (up to 39.3% in ZN4). Ga, Rb, Sr and Y generally vary significantly within ±50% while Zr is consistently grossly underestimated by 40 to 100% when measured by ICP-MS due to highly insoluble Zr phases. Nb as well varies a lot being mostly underestimated by the ICP-MS. Mo is often only present in trace amounts and therefore particularly prone to 137

varying outcomes depending on the measurement method applied but except for KY1 and CXP10 remains within 30% difference (see Fig. Fig. 4.7). Ba conmcentrations mostly agree well within 20 to 30% except for the very high concentration in ZN4 where the ICP-MS measurement is ten times lower than the XRF value. The Rare Earth Elements La, Ce and Nd generally agree well and discrepancies of over 30% are only found where concentrations are low, such as in HL14 and XT5. Pb and Th exhibit significant variations as well and Th in particular is extremely underestimated in the CXP samples analysed by ICP-MS. However, although we often found different results for elements concentrations depending on the method used, a good correlation between XRF and ICP-MS for each sample can generally be expected as demonstrated in figure 4.7. Mo concentrations do exhibit significantly different results when both analytical methods are compared, exceeding 50% in some samples but V concentrations agree reasonably well with each other (see Fig. 4.8), which might be due to the usually much lower Mo contents compared to V and hence, a greater affinity to inaccuracies due to sample preparation and contamination.

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Figure 4.7: Covariation patterns of element concentrations obtained by both, XRF and ICP-MS measurements. The orange beam represents 10% and the yellow beam 20% deviation. Note that the fundamentally different sample preparation method for the respective analytical technique may lead to significant differences for some elements in some samples largely depending on the lithology in particular for Ti which is often strongly underestimated by ICP-MS analysis due to its incorporation into insoluble siliciclastic components, and Ba due to difficultly soluble barite crystals.

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Figure 4.8: Covariation patterns for Mo and V analysed by XRF and ICP-MS. The orange beam represents 10% and the yellow beam 20% deviation. Note that low Mo concentrations might be prone to inaccuracies of up to 50% and more. Obtained V concentrations agree reasonably well and differences remain mostly within 20% without a consistent trend.

4.3.

Iron speciation analysis

4.3.1. The procedure

The sequential extraction procedure for iron recognizes seven operationally derived iron pools (see chapter 2.3; Poulton and Canfield, 2005): (1) carbonate associated Fe (Fe carb), including siderite and ankerite; (2) easily reducible oxides (Feox1), including ferrihydrite and lepidocrocite; (3) reducible oxides (Feox2), including goethite, hematite and akaganéite; (4) magnetite (Femag); (5) poorly reactive sheet silicate Fe (FePRS); (6) pyrite Fe (Fepy); and (7) unreactive silicate Fe (FeU). The highly reactive portion of the iron pool includes Fecarb, Feox, Femag and Fepy which, except for Fepy, were sequentially extracted according to the methods outlined by Poulton and Canfield, 2005 whereby Feox1 and Feox2 (→ Feox) were extracted together, as a differentiation of these two iron pools is not necessary for our purpose. The 141

sequential extraction was carried out using one unit of each powdered sample ranging from 50 to 100mg. Fecarb was extracted from the sediment by adding 10ml of 1M sodium acetate adjusted to pH 4.5 by using acetic acid into the test tube which is then shaken for 48h at 50°C (Tessier et al., 1979). The resulting solution was carefully removed from the test tube and diluted 20 times in water. For extracting Feox, a sodium dithionite solution (50g l-1) buffered to pH 4.8 with 0.35M acetic acid and 0.2M sodium citrate (Mehra and Jackson, 1960; Lord III, 1980) has been prepared and used immediately after preparation in order to prevent the solution from oxidizing. 10ml of the solution was then poured into the test tube and then shaken for two hours at room temperature before being diluted 20 times. Femag in the remaining sediment was extracted by adding 10ml of a 0.2M ammonium oxalate and 0.17M oxalic acid solution (pH 3.2; McKeague and Day, 1966; Phillips and Lovley, 1987), the resulting solution being diluted in the same way as for the Fecarb and Feox2 extraction. The extraction of pyrite Fe (Fepy) has been done separately by weighting about 4g of sample powder (depending on the broadly estimated pyrite content). The equipment for the sulphide extraction consisted of an array of six round glass flasks on hot plates whereby the flasks have three apertures one for introducing the sample powder, one for the influx of an inert gas (N2) and one leading into a condensating unit which ends into a plastic tube with a pipette in a test tube. During the procedure, two Fe sulphide phases have to be taken into consideration: acid volatile sulphide (AVS) and chromium reducible sulphide (CRS). AVS is rare in ancient sediments and basically corresponds to the FeS content, a precursor of FeS2. The eventual occurrence of AVS was detected by heating up the sample after adding a 50% HCl solution (Cornwell and Morse, 1987), the resulting H2S gas is then led, supported by a flow of N2 gas, into a water filled test tube with added silver nitrate (usually 0.25ml of 170g l -1 silver nitrate) which results in the precipitation of Ag2S which is then collected. The extraction of AVS lasts about 15min. The subsequent extraction of CRS is attained by adding chromous chloride (CrCl2, 533g l-1, Canfield et al., 1986) to the sediment and boiling it for one hour. The escaping H2S gas resulting from the dissolution of Fe2S was then again precipitated as Ag2S in the test tube with silver nitrate which would have been replaced if the previous extraction with HCl yielded a significant amount of AVS. The collected Ag2S precipitates were then carefully filtered 142

and dried before being weighted and the corresponding concentration of FeS 2 originally contained in the samples can be calculated. It must be considered that a slight loss of sulphide can occur using this method, especially in sulphide poor samples. In order to evaluate the total iron concentration (Fe T), the sample powder has to be completely dissolved. At first, a sample amount ranging between 100 and 200mg has been weighed into porcelain beakers and ashed overnight at 550°C in order to get rid of insoluble organic matter and sulphides. 5ml of nitric acid was then added to the ashed powder followed by 2ml hydrofluoric acid (HF) and a few drops of HClO4. The mixture was dried (normally overnight) on a hot plate at 130°C. Then, 2.5ml boric acid (50g l-1) were added and dried up again. The remains of each sample were then again dissolved in 5ml of 50% HCl and heated on a hotplate until total dissolution occured. The resulting solution was diluted by first filling it up to 100ml with water and second by taking 0.1ml of this solution and diluting it into 4.9ml of water, resulting into a solution of 5l for every powdered sample. The concentration of Fecarb, Feox, Femag and FeT in the prepared solutions were measured using an atomic absorption spectrometer (AAS) and calculated back to the original concentration in the respective samples.

4.3.2. Comparing total iron measurements (XRF and AAS)

One can imagine that precise concentrations of total iron are crucial for reliable iron speciation analysis. As already mentioned, in certain cases total dissolution of a given sample can barely be attained and this might also affect FeT concentrations measured with the AAS. It is therefore not surprising that FeT concentrations measured by XRF generally yield slightly higher FeT contents although with a few exceptions (see appendix). However, AAS results agree very well with the presumably more precise XRF values, rarely showing more than 20% difference (see Fig. 4.9).

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Figure 4.9: Plot showing the almost perfect correlation of FeT concentrations obtained by AAS and XRF. The orange beam represents 10% and the yellow beam 20% deviation.

4.4.

Carbon and sulphur analysis

4.4.1. C/S analyser

The measurement of carbon and sulphur concentrations has been carried out with a Leco C/S analyser at the Wolfson Laboratory, University College London. The C/S analyzer works as an induction furnace whereby carbon is oxidised to CO2 and sulphur to SO2 which is then measured by infrared detectors. The sample powders have been analysed for total carbon and total sulphur after weighing around 200mg into ceramic crucibles and the addition of iron chips to accelerate the burning process. For total organic carbon (TOC) measurement, the sample was treated with a 10% hydrochloric acid (HCl) solution in porous crucibles to dissolve carbonate whereby under some circumstances where high dolomite contents could be expected, a few drops of concentrated HCl have been added. After the subsequent filtering, a thorough rinse and drying the sample overnight, TOC contents have been measured following the above procedure. The accuracy of the results has regularly been checked by introducing a reference material after every 10 samples and a few samples have been measured twice and agree within 10% uncertainty.

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4.4.2. Sulphide isotopes

For samples which yielded enough Ag2S residue (>0.03g) after the sulphide extraction procedure (see chapter 4.3.1.) have been analysed for sulphide isotopes using a Finnigan MAT DeltaPlus plumbed to a Carlo Erba elemental analyser through a Conflo II interface. All analytical work has been carried out by the group of Prof. Harald Strauss at the Institute for Geology and Paleontology, University of Münster, Germany.

4.5.

Trace-metal normalisation The trace-metal content in organic-rich sediments is composed of three sources which

are 1) terrestrial input through rivers or as aerosols, 2) plankton and 3) early diagenetic enrichment (e.g. Brumsack, 2006). To better reflect authigenic trace-element accumulation and rule out possible terrestrial contamination, trace-metal concentrations are often normalized to an element of predominantly, if not exclusively, detrital origin which is not affected by biological or diagenetic processes. Al is commonly used for that purpose but as it is often not included in the dataset, other elements such as K, Li, Sc, Ga, Zr and Ti can as well be used (e.g. Van der Weijden, 2002). Instead of simply normalizing a given trace-element to Al, enrichment factors are often used. This consists of dividing normalized trace-elements in the sample by the respective normalized trace-element in average shale:

Any possible enrichment is then indicated by EF values exceeding 1 and depletion of the element in EF values less than 1. Average shale composition and the roughly similar upper continental crust (UCC) composition has been evaluated ever since people have investigated shales (Wedepohl, 1971, 1995; Taylor and McLennan, 1985; Drever et al., 1988; McLennan,

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2001) even for black shale specifically (Yudovich and Ketris, 1994). A further advantage of normalizing trace-metal contents is that it corrects for dilution by carbonates and other mineral phases devoid of Al (or another normalizing factor), which on the other hand can lead to unrealistically high enrichment factors or to other misleading results such as spurious correlations between trace-elements (Van der Weijden, 2002; Brumsack, 2006). Another approach is to evaluate the non-detrital or excess fraction of a given trace-metal (Brumsack, 2006):

However, the analysis of trace-metal concentrations and their eventual normalization to average shale or exclusively detrital elements has to take into account numerous factors which can affect the mineral composition of the sediment, such as diagenetic alteration and atypical mineral provenances. For the present study, trace-metal concentrations have preferentially been normalized to Sc as it is part of the dataset acquired by both, XRF and ICP-MS analysis. The error margins in measuring Sc content by ICP-MS are also significantly smaller than for Ti for instance although Sc is generally present at much lower concentrations (see chapter 4.1.4.). In addition, Kimura and Watanabe (2001) found that V varies in proportion to Sc rather than other insoluble elements such as Al and Ti (see also Guo et al., 2007).

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5.

Results and discussion of the investigated sections In the following chapter several elements are mentioned as part of the analytical results

but the discussion and interpretation mostly focuses on Mo, V and U, iron speciation analysis and Fe-S-C systematics. In some cases P, Ba Mn and Ni constitute an important characteristic of a sedimentary succession and deserve special attention. The traditionally used paleoredox proxies Th/U and V/(V+Ni) are mentioned for comparison but are of limited use in marine sediments deposited before and during the Precambrian – Cambrian transition where the biogeochemical cycling of redox-sensitive trace-elements experienced major perturbations. A few carbonate successions have been included and the results are outlined for the middle Dengying Fm. (Shibantan Mb.) and uppermost Zhujiaqing Fm. (Dahai Mb.) without much discussion as, although respectable TOC contents are sometimes attained, no significant enrichement in redox-sensitive elements took place.

5.1.

The Cryogenian

5.1.1. The Datangpo Formation: a geochemical profile from the manganese mine at Changxingpo, Guizhou Province

A short interval of 2.25m has been sampled at the Changxingpo Mine including the black shale succession, which is more appropriately described as carbonaceous marl, at the base of the Datangpo Fm. They overlie the glacial deposits of the Tiesiao Fm. and are rather thin, based on the analysed TOC contents, and do not exceed 50cm. Although the sediments yield higher organic content further up, this increase in TOC content is accompanied by increasing Mn concentrations up to over 17% in the manganese-carbonates whereby a good correlation between TOC and Mn is observed throughout the sampled section (R 2 = 0.65). Total sulphur concentrations are rather high at the top of the Tiesiao Fm. near the boundary (5.6%) but remain around 2% prior to the deposition of the Mn-carbonate. Pyrite and TS contents correlate well but there is a significant amount of non-pyrite sulphur of about 70%. Total Fe 147

content varies between 1.2 and 4.3% whereby the lowest values are found within the Mncarbonate and the highest at the top of the Tiesiao Fm. P concentrations are all below 0.3% and negatively correlated with Fe contents. Ba concentrations increase from the carbonaceous marl on and reach a maximum of 1252.6 ppm about 25cm below the Mn-peak. Mo and V concentrations are relatively low and moderately enriched with Mo within the carbonaceous marl (up to 28.6 ppm). The same applies to other redox-sensitive trace-metals such as U but also Ni, Cu, Zn etc. FeHR/FeT ratios remain above 0.38 except for the region around the Tiesiao/Datangpo boundary where they decrease to around 0.32. Th/U ratios are greatly elevated with two digit values and a maximum of 93.8 and V/(V+Ni) decrease upwards to values below 0.6 within the Mn-carbonates. Pyrite sulphur isotopic values are greatly elevated, varying between 20 and 60‰ which broadly track Mn concentrations.

Figure 5.1: The geochemical profile across the Tiesiao/Datangpo boundary in the Changxingpo Mine. Note that the carbonaceous marl at the base of the Datangpo Fm. has been qualified as black shale in several other basal Datangpo successions (e.g. Chen et al., 2008; Feng et al., 2010). Dashed curves indicate lower resolution. The FeHR/FeT threshold for anoxic deposition of 0.38 is indicated by a dashed black line and the threshold of 0.7 above which FePy/FeHR ratios indicate deposition under euxinic conditions is indicated by a dashed red line.

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5.1.2. Discussion

Manganese is usually delivered to the sediment as Mn-oxyhydroxide (mainly MnO2 and MnOOH) in the form of oxide coatings on detrital particles where it can be released when reducing conditions are met (see review by Tribovillard et al., 2006). Mn-oxyhydroxides can also dissolve while settling through the water column and in an anoxic water column, Mn accumulates as Mn2+. When clastic sedimentation is low, this causes Mn-oxyhydroxides to accumulate along the margin of an anoxic deep water body where the reaction with organic matter leads to the formation of secondary Mn-carbonates, which represents the only sink for Mn because the redoxcline acts as an efficient barrier against Mn loss (Brumsack, 2006), due to a shift towards more alkaline conditions (e.g. Liu et al., 2006): 2MnO2 + CH2O + HCO3- = 2MnCO3 + H2O + OH-

Because about one half of the carbon in Mn-carbonates derives from organic carbon, δ13C values are usually relatively low (Liu et al., 2006). Furthermore, the oxidation of organic matter by Mn-oxyhydroxides also removes any pyrite in the sediment (Aller and Rude, 1988). Both the correlation between Mn and TOC contents and the decreasing total sulphur and pyrite content as Mn contents increase support that Mn accumulated together with decomposing organic matter and thus suggest at least moderately oxic conditions (e.g. Calvert and Pedersen, 1996; see also Feng et al., 2010). But that also means that eventual diagenetic pyrite formation takes place relatively late, after Mn-oxyhydroxides converted to Mn-carbonates from a limited amount of sulphate within the sediment. Together with restricted access to sulphate in the overlying waters this results in very heavy δ34SPyrite values (Okita, 1992). Heavy S-isotopes are common in sediment-hosted Mn deposits and has been demonstrated in several Chinese Neoproterozoic deposits and elsewhere (Tang and Liu, 1999; Li et al., 1999a; Liu et al., 2006 and references therein). Manganese ores are often found in close association with glacial deposits and therefore occur more abundantly in the Paleo- and the Neoproterozoic with a well-defined gap between

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1800 and 1120 Ma (see Fi. 1.2b, Maynard, 1991; Roy, 2006; Maynard, 2010). A model by Gorjan (2000, 2003) suggested ocean turnover after the melting of ‘Snowball Earth’ whereby Mn (and Fe) rich upwelling waters which would have caused the widespread deposition of Mn (and Fe) deposits. But Liu et al. (2006), who studied the manganese ore on several sections on the Yangtze Platform, pointed out that sedimentary manganese ores are often interbedded with glacial deposits and are more likely found in narrow rifts than open shelves which is better explained by a ‘Slushball’ or ‘Zipper-Rift Earth and partially retreating ice sheets (see review by Fairchild and Kennedy, 2007). An enhanced source for Mn and Fe would have been rapid deposition of lateritic soil residues introduced by low latitude glaciers into a suboxic or anoxic basin (Liu et al., 2006). Low concentrations in trace-metals could indicate a depleted seawater inventory prior to the Neoproterozoic Oxygenation Event. Alternatively, the low Mo and V concentrations with maxima below the Mn-carbonate could indicate an anoxic to suboxic environment during the deposition of the carbonaceous marl and the very low U content possibly even diagenetic remobilisation probably due to a redoxcline below the sediment-water interface and further support an environment prone to extensive Mn deposition. The Fe HR/FeT ratio is negatively correlated to total Fe concentrations (R2 = 0.65) suggesting that the iron chemistry is dominated by detrital and glacial processes and the use as paleoredox indicator is dubious. However, higher Fe enrichment and pyrite sedimentation at the top of the Tiesiao Fm. and in the black shale prior to the Mn-carbonate further illustrate the greater insolubility of iron sulphide compared to Mn sulphide (alabandite; e.g. Liu et al., 2006). Similar to Fe, the lack of significant redox-sensitive trace-metals enrichment reflects their characteristic to form insoluble sulphide minerals which are therefore likely to be scavenged in deeper, anoxic portions of the water column (Maynard, 2010).

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5.2.

The Ediacaran and Precambrian – Cambrian boundary sections

5.2.1. The Maoshi section, Guizhou Province: A Doushantuo/Dengying boundary succession

The Doushantuo/Dengying boundary section, with a total length of about 19m (see Fig. 5.2), shows elevated TOC contents within the upper Doushantuo Fm. of between 1 and 3.6% which roughly correlate with high total sulphur contents of up to 3.25%. Almost all sulphur is present in pyrite except in one sample (MS10) about 9m below the boundary to the overlying Dengying Fm., where significant non-pyrite sulphur is indicated. There is no significant tracemetal enrichment and concentrations vary slightly around upper continental crust (UCC) values. Accordingly, we find very low Mo/TOC below 4*10-4 and V/TOC ratios with a maximum of 144.5*10-4. Fe and P contents are broadly correlated within the upper Doushantuo Fm. with maxima of 3.5% and 0.8% respectively. The upper Doushantuo Fm. is overall depleted in Mn and slightly enriched in Ba, the latter showing gently decreasing concentrations across the Doushantuo/Dengying boundary and correlating very well with V concentrations (R2 = 0.84). Iron speciation data indicates anoxic conditions throughout with a possibly euxinic interval around 5m below the formation boundary where FePy/FeHR ratios reach values above 0.7 over a length of about 2.5m. This interval is followed by a drop in S, Fe, Mn and Mo but not V while TOC even increases. V/(V+Ni) ratios are between 0.6 and 0.95 with overall lower values within the basal Dengying Fm. The FeHR/FeT ratio drops to 0.17 in the uppermost sample from the Dengying Fm. concomitant with a FeT content of only 0.04%.

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Figure 5.2: The geochemical profile from the Doushantuo/Dengying boundary section at Maoshi. Yellow shaded intervals indicate intermittently euxinic conditions.

5.2.2. The Doushantuo Formation in the Three Gorges Area, Hubei Province

5.2.2.1. The Member II at Jiulongwan

The profile starts about 1m above the cap carbonates from the lowermost Doushantuo Fm. and 1m below the onset of black shale deposition, where TOC and TS reach concentrations above 2% (see Fig. 5.3). For the rest of the succession, sulphur concentrations track TOC contents which vary between slightly below 1 and 2.7%. TS and pyrite sulphur correlate very well and there is a relatively consistent percentage of non-pyrite sulphur of about 20% except for a few samples with an overall low concentration of sulphur and analytical inaccuracies might play a role. Redox-sensitive trace-metals are within the range of UCC values or depleted throughout the section with maxima of Mo below 4.5 ppm, a maximum of V of 80 ppm and a U peak of 3.2 ppm. While some peaks occur concomitantly, such as at the base of the formation, Mo and V correlate only weakly and the best correlation is found between V and U. Other trace-metals such as Ni and Cu are almost exclusively depleted throughout. The Fe concentration pattern across the profile appears cyclical with values between 0.5 and 2.5% and 152

although there are significant interruptions in the stratigraphic column, it appears that variations in Fe content occur at an upwards diminishing frequency. Mn is enriched at the base of the Doushantuo Mb. II to concentrations of up to 2361 ppm and decreases stepwise to depleted values below 400 ppm. At that point, Ba concentrations increase over a few meters up to a maximum of 1075 ppm before decreasing slowly towards depleted values again further up the section. Mo/TOC ratios are very low and don’t exceed 4*10 -4 and the same applies to V/TOC ratios where a maximum of 135.2*10-4 is found. The Th/U ratio shows values above 5 in the first meter of the profile and then decreases to values below 2 for the rest of the sampled succession. Somehow contradictory, the V/(V+Ni) ratio shows higher values at the bottom of the section and then falls below 0.7 further up. Iron speciation shows that FeHR/FeT ratios are mostly high and above 0.38 except in two isolated samples where we find ratios of 0.25 and 0.21. A few values exceed 1 which is probably due to a certain fraction of barely soluble iron phases (one ratio of above 3 was excluded from Fig. 5.3). Some FePy/FeHR ratios attain values close to 0.7 at the base of the section and further up where a single value of 0.76 is found. Sulphur isotopes in pyrite are exclusively positive throughout the section exhibit significant variations between close to 0 and 22.9‰ (VCDT) with maxima at the base of the succession and on top within intervals with high FePy/FeHR ratios.

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Figure 5.3: The geochemical profile of parts of the Doushantuo Member II at Jiulongwan. Note that the disruptions in the stratigraphy are due to non-exposure of unknown lengths. The yellow shaded areas indicate sedimentation under euxinic conditions while the interval at the base of the section shows possibly euxinic conditions with FePy/FeHR ratios of 0.66.

5.2.2.2. The Miaohe Member (Mb. IV) at Jiulongwan

A profile of about 20m length has been measured from the upper part of the Doushantuo Mb. III dolomites until the top of the black shales of the Miaohe Mb. at the boundary to the overlying Dengying Fm. (see Fig. 5.4). TOC contents gradually increase to values averaging more than 5% with a distinct peak of almost 15% a few decimetres below the Doushantuo/Dengying boundary. TS concentrations are more variable, rising to values above 2% at the base of the black shale, showing a distinct peak of 5.7% in the middle of the Miaohe Mb. and a decrease followed by a high concentration of 5.4% just below the Doushantuo/Dengying boundary. There is a weak negative correlation between TOC and TS whereby the highest TOC 154

contents at the top of the black shale correspond to low TS contents. TS and pyrite sulphur are well correlated with varying but minor amounts of non-pyrite sulphur. Mo concentrations are highest at the base of the black shale with 367.3 ppm and oscillate between 16.6 and 426.9 ppm further up towards the Dengying Fm. V concentration patterns are similar, with a maximum of 2404.8 ppm followed by variations between 171.1 and 2059.7 ppm. The U content varies between 3.2 and 31.5 ppm in the Miaohe Mb., the maximum value being found in the middle of the black shale succession. Normalization to Sc does not significantly affect sedimentary accumulation patterns. Other trace-metals, such as Ni and Cu are only moderately enriched except at the top of the Miaohe, where we find Ni and Cu depletion. Fe concentrations are very low within the uppermost Mb. III and increase to values between 2.3 and 3.9% within the Miaohe whereby values below 1% are attained at the top of the Miaohe before a maximum of 4.8% is seen just underneath the boundary to the overlying Dengying Fm. Mn is generally depleted with respect to UCC with one peak of 857.4 ppm within the middle part of the black shale which corresponds to relatively low trace-metal concentrations. Ba varies strongly between a few hundred and 4782.2 ppm. Mo, V and U correlate moderately with each other whereby the best covariation is seen between Mo and V (R 2 = 0.53). There is no correlation between the analysed trace-metals and TOC or TS except for a weak negative correlation between V, Ni, Cu and TOC. Mn correlates weakly with Ni only, whereas the latter correlates moderately with Mo, V, U, Cu, Mn and Ba (R2 Є *0.2, 0.4+). Cu is moderately correlated to TS and Fe, Fe being negatively correlated to TOC. Mo/TOC ratios show a very high value of 181.2 at the base of the Miaohe Mb. and seem to decrease rapidly to values between 0.2 and 41.6. The V/TOC ratio as well is high at the base of the Miaohe Mb. (1186.4) and decreases to values between 11.3 and 493 within the overlying sediments. Th/U ratios switch from values above 2 in the uppermost Mb. III to mainly very low values in the Miaohe except within the layer a few dm below the boundary to the overlying Dengying Fm. V/(V+Ni) ratios increase at the Mb. III/Miaohe boundary to values mostly above 0.9. Iron speciation data shows high FeHR/FeT ratios close to 1 throughout the profile while FePy/FeHR ratios are above 0.7 about 4m below the Mb. III/Miaohe boundary followed by a short decrease to 0.44 before rising again towards very high ratios of between 0.7 and 1 in the

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Miaohe black shale until another decrease to minimum of 0.57 less than 1m below the Doushantuo/Dengying boundary. The sample from the boundary interval shows again a FePy/FeHR ratio of 0.86. Lower FePy/FeHR ratios correspond to low FeT contents below 1% which might cause some unreliability. Pyrite sulphur isotopic values are negative between -5.9‰ (VCDT) within the upper Mb. III and -19‰ (VCDT) on top of the Miaohe within an interval where TS contents and Th/U ratios track the isotopic record.

Figure 5.4: The geochemical profile from the upper part of Doushantuo Mb. III to the Doushantuo/Dengying boundary. Yellow shaded intervals represent euxinic depositional conditions and the lighter shaded interval at the top of the Miaohe Mb. suggests a short period of non-sulphidic conditions until the boundary.

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5.2.2.3. Member II and the Miaohe Member at Jijiawan

Samples have been analysed for black shale intervals of the Mb. II and the Miaohe Mb. of the Doushantuo Fm. (see Fig. 5.5). TOC contents are variable between 0.8 and 4% and TS concentrations remain around 1% within Mb. II. In the Miaohe black shale, TOC concentrations are very high at the base with a maximum of 5.6% and remain largely below 3% for the rest of the succession. TS concentrations remain below 2% until the top of the Miaohe, shortly before the boundary to the overlying Dengying Fm. where a maximum of 2.3% is found. There is a good correlation between TS and pyrite sulphur with variable amounts of non-pyrite sulphur averaging about 40%. Mo concentrations are low throughout with the highest value of 7.3 ppm within Mb.II. The same applies to V with a maximum of 116.7 within the Miaohe and U with a maximum of 2.5 ppm within Mb. II. Ni and Cu as are mostly below UCC values. The major elements Fe and Mn are also depleted with averages of 1.45% and 110.6 ppm respectively whereby the carbonates in Mb. II are less depleted in Mn but slightly more depleted in Fe. Within the Miaohe, moderate to good correlation is found between Mo, U, Ni, Cu and TS, whereby TS correlates well with redox-sensitive metals insoluble under reducing conditions such as Mn. In addition, good correlation (R2 = 0.61) is seen between V and Fe. Mn correlates moderately with U and Ni. Mo/TOC ratios are low throughout the section with a maximum of 5.4*10-4 on top of the Miaohe where a concomitant peak in V/TOC ratios of 170.8*10 -4 is found. Th/U is below 2 within Mb. II and highest in the lower part of the Miaohe with a ratio of 2.9. V/(V+Ni) is mostly below 0.64 in Mb. II and increases in the Miaohe where ratios remain above 0.64. FeHR/FeT ratios are consistently above 0.38 in both members and FePy/FeHR ratios vary between 0.49 and 0.69 within the Miaohe with the highest ratios on top. δ 34SPyrite values are negative within the stratigraphically oldest sample (-10.5‰) but increase to positive values above 10‰ (VCDT) further up with a maximum of 23.2‰ within the Miaohe.

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Figure 5.5: Analytical results for the lower part of the Doushantuo Mb. II and the Miaohe Mb. at Jijiawan. Note that the gap between Mb. II and the Miaohe is unknown but in the range of a few tens of meters. The light yellow interval indicates deposition under possibly sulphidic conditions with FePy/FeHR ratios between 0.63 and 0.69.

5.2.3. Ocean chemistry and platform evolution in the Ediacaran

The short interval sampled from the Doushantuo Mb. II at Jijiawan is geochemically similar to the more extended profile analyzed at Jiulongwan, where we find no enrichment in redox-sensitive trace-metals, comparable TOC and TS contents, overall anoxic conditions and mostly positive δ34SPyrite values above 10‰ (VCDT). Past geochemical studies from the Jiulongwan section in the Three Gorges Area agree with our results (Bristow and Kennedy, 2009; Li et al., 2010) and suggest that low trace-metal concentrations are likely a widespread characteristic on the platform and margin during the deposition of the Doushantuo Mb. II. Low to moderate enrichment of Mo and V in Mb. II has been reported from slope and basin sections, where Mo concentrations can reach a few tens of ppm (Wallis, 2006; Guo et al., 2007). Although there are indications for intermittent euxinia in Mb. II at Jiulongwan, suggested by high FePy/FeHR ratios close to 0.7, no Mo enrichment took place. Because Mo/TOC and V/TOC 158

ratios remain accordingly very low throughout the lower part of the Doushantuo Fm., a limited reservoir of Mo and V in the water column is strongly suggested during the deposition of the Doushantuo Mb. II, which can either be due to globally reduced oceanic trace-metal budgets or to a certain extent of basin restriction, such as seen in the Black Sea today (Algeo and Lyons, 2006; Scott et al., 2008; Jiang et al., 2011). Paleogeographical, sedimentological and carbon isotope studies support a rimmed platform margin and the formation of restricted basins on the Yangtze Platform (Jiang et al., 2003, 2008, 2011; Vernhet, 2007; Vernhet and Reijmer, 2010), indicating geographical barriers as main trace-metal limiting mechanism. However, Bristow and Kennedy (2009) recently carried out a study on Mb. II at Jiulongwan and found abundant saponite, a clay mineral predominantly formed under elevated pH (>9) in alkaline lakes and hypothesized that Mb. II could have been deposited in a non-marine environment without access to the open ocean. Furthermore, δ34S values in pyrite are very variable but generally enriched in

34

S resulting from quantitative sulphate-reduction and a sulphate-poor water

column which could also result from restricted access to the open ocean. A further possibility would be widespread euxinia during the deposition of Mb. II, effectively depleting the oceanic reservoir of sulphate and redox-sensitive trace-metals but there is no evidence for long-lived and sustained euxinia neither on the Yangtze Platform nor elsewhere in the world during that time (Canfield et al., 2008). And, last but not least, low atmospheric oxygen levels prior to the NOE could have effectively limited oxidative weathering and the ocean would remain depleted in molybdate and sulphate during the Early Ediacaran. Such a scenario is enticing and may constrain the NOE better in time but Jiang et al. (2011) recently suggested that the platform margin developed into a rimmed-shelf relatively soon after the deposition of the cap carbonates ca. 635 Ma and would have possibly restricted the depositional environments north of the platform margin making the paleobathymetric setup the controlling parameter regarding trace-metal and sulphate availability (see Fig. 5.6). The black shales from the Miaohe Mb. were clearly deposited under euxinic conditions at Jiulongwan whereby the negative correlation between TOC and TS may suggest a negative feedback on biological productivity through sulphidic waters possibly reaching the photic zone. Euxinia is less well supported at Jijiawan where a maximum FePy/FeHR ratio of 0.69 is observed. 159

The geochemistry at Jijiawan might have been altered by weathering (see chapter 3.1.2.), resulting in oxidation and remobilization of redox-sensitive elements. Intermittently euxinic conditions are also indicated within the uppermost Doushantuo Fm. at Maoshi, which is about 530km south west of the Three Gorges Area, suggesting widespread euxinic conditions on the borders of the platform during deposition of the upper Doushantuo black shales. Element concentrations and sulphide isotopes are strikingly different between the Jiulongwan sections and both, Jijiawan and Maoshi sections. Whereas Mo, V, U and most other redox-sensitive metal concentrations are within the range of average shale (or UCC) values at Maoshi and Jijiawan, we find the highest Precambrian Mo concentrations (>300 ppm) so far on record within the Miaohe Mb. at Jiulongwan. Furthermore, while sulphide isotopes are exclusively and distinctively negative in the Miaohe black shale at Jiulongwan, averaging -11.2‰ (VCDT), we find mostly positive values at Maoshi, averaging 9.9‰, and at Jijiawan with an average of 18.4‰. The evolution of the Yangtze Platform margin during the deposition of the Ediacaran Doushantuo Fm. can tentatively be constrained in time and space on geochemical proxies alone if we assume a global oceanic Mo and sulphate reservoir in the range of modern magnitude. The Nantuo Fm., deposited during the Marinoan Glaciation, represents the last stage of the rifting history of the Yangtze Platform and left the morphology with abundant horst and graben structures (see Fig. 3.3; Vernhet, 2007) onto which the sediments of the Doushantuo Fm. have been draped. A mosaic of different depositional environments can therefore be imagined which has been confirmed by studies demonstrating significant lateral facies variations, notably around the Three Gorges Area, including rims, protected shallow-water basins and intra-shelf basins (Fig. 5.6; Vernhet, 2007; Vernhet and Rejimer, 2010). A rising eustatic sea-level would have successively allowed these restricted or semi-restricted basins access to the open ocean and thus increased the availability of redox-sensitive trace-metals to be scavenged by anoxic and even sulphidic bottom waters (see Fig. 5.7). Low sulphate concentrations in the water column during the deposition of Mb. II were sufficiently counteracted by overall low Fe(II) concentrations to allow episodic euxinia to develop. The pronounced euxinic sediments of the Miaohe Mb. at the Jiulongwan section are accompanied by very high Mo/TOC ratios and negative sulphide isotope values, suggesting an almost unlimited supply of redox-sensitive

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trace-metals and sulphate by the overlying shallow, oxic ocean and enhanced by the limited extent of the euxinic water masses, in the form of a sulphidic wedge, for instance, as proposed by Li et al. (2010). The Miaohe Mb. sediments at the Jijiawan section do not exhibit any enrichment of redox-sensitive trace-metals and pyrite is enriched in 34S and suggest that while depositional environments closer to the platform margin had unrestricted access to the open ocean, some intra-shelf basins remained isolated further within the inner platform. This also applies to the sediments deposited at the Maoshi section, which exhibits similarly low Mo, V and U enrichments along with positive sulphide isotope signatures (see Fig. 5.2 and 5.6c).

Figure 5.6: A) A rimmed shelf model by Vernhet and Reijmer (2010) where the large dimensions of the shelf allow for further diversification of depositional systems. B) An open shelf model, also by Vernhet and Reijmer (2010). C) The rimmed shelf model by Jiang et al. (2008) based on studies on the Doushantuo Fm. in Guizhou Province. The Maoshi section is located near Songlin, within the intra-shelf basin.

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Figure 5.7: A) shows a restricted intra-shelf basin with a stratified water column including intermittent euxinic conditions such as might have been the case during the deposition of the Doushantuo Mb. II. B) A model schematically illustrating how the Miaohe Mb. might have been deposited in different environmental settings. The sulphidic wedge, analogous to modern oxygen-minimum zones, has been adopted from Li et al. (2010) to account for the very high enrichment in redox-sensitive trace-metals observed at Jiulongwan.

5.2.4. A high-resolution profile from the top of the Miaohe Member at Jiulongwan

5.2.4.1. Results

The ca. 80 cm long interval recovered from the upper part of the Miaohe Mb., about 20 cm below JLW42, consists of pyrite rich, finally laminated black shale whereby 7 individual blocks of 5cm length have been sawn out and subjected to Laser Ablation ICP-MS (see Fig. 4.4a).

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The results have been averaged for each individual sample which is shown in figure 5.8 while the detailed results can be found in the appendix. Average Mo concentrations vary between 154 and 293 ppm, average V concentrations between 877 and 1429 ppm and average U concentrations between 26 and 40 ppm. There is no correlation between Mo and V but a moderate covariation is observed between Mo and U contents, exemplified by the minimum average Mo concentration occurring together with the minimum average U concentration but the maximum average V concentration. Mn contents are relatively low but gradually increase up-section to a maximum average of 810 ppm while a very high variability is observed for average Ba concentrations of between 543 and 9931 ppm which tend to be inversely correlated to Mo contents. The high resolution profiles can be found in the appendix and only MI2, sampled about 25cm below JLW42, will be discussed further at this stage (see Fig. 5.9). Mo concentrations generally remain around 200 ppm but show a few pronounced peaks within the lower part of the profile, where three distinctively enriched horizons follow each other with Mo contents gradually increasing to over 1000 ppm. This interval correlates with elevated Mn contents and is between very high Ba concentrations up to several percent. Another single Mo peak with concentrations up to almost 2000 ppm within the upper part is again accompanied by a prominent Mn maximum of about 4000 ppm and preceded by high Ba concentrations which can attain over 3%. V contents are mostly between 750 and 1500 ppm with a few layers which can reach almost 3000 ppm but are not correlated with other elements analysed here. U concentrations are mostly below 100 ppm with a suite of higher contents of up to 200 ppm in the middle and single peak on top of the profile. Th/U ratios mostly remain well below 2 but show a few enriched layers with values between 2 and 8, first between the 2 nd and 3rd Mo peak within the lower part and second, before and after the maximum Mo and Mn concentrations within the upper part.

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Figure 5.8: Averaged redox-sensitive element concentrations from the LA-ICP-MS analysis performed on seven black shale samples from the uppermost Miaohe Mb. at Jiulongwan. Note that most concentrations are much higher than the bulk rock data in figure 5.4 which might result from particularly the unweathered and homogenous sample selection for the LA-ICP-MS.

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Figure 5.9: High resolution geochemical profile perpendicular to the lamination across MI2, a 5cm long sample from the uppermost Miaohe Mb. at Jiulongwan. The grey shaded areas indicate episodic Mo and Mn enrichment after and-or between two intervals of anomalously high Ba enrichment and the orange line indicates high Th/U ratios above 2 within the lower interval. Note that some isolated Ba concentrations significantly exceed 10% and are not shown here.

5.2.4.2. Discussion

The consistently higher average concentrations from the LA-ICP-MS analysis compared to the bulk rock data, in particular for Mo and to a lesser extent for V, might result from a more careful selection of homogenous samples and polished surfaces. Alternatively, the calibration after the internal standard (Si), as outlined in chapter 4, might impact on the analytical results due to the mineralogical heterogeneity of the samples. However, even from a semi-quantitative 165

point of view the high-resolution profiles exhibit geochemical changes in the mm-scale and give insight into short term variations of the biogeochemical cycling of redox-sensitive trace-metals. The lowermost 2cm of sample MI2 in particular exhibits interesting and very sharp switches from Ba to Mo and back to Ba. This could suggest episodic blooms in productivity under oxygen depleted but non-sulphidic bottom water conditions followed by periods of intermittent euxinia which lead to enhanced Mo sequestration from the water column. But it is more likely to indicate a dynamic redoxcline with varying depth, leading to sulphate (BaSO 4) precipitation when within the sediment and sulphide and concomitant Mo removal when bottom water euxinia developed. The fact that such changes are resolved within the range of a few millimetres is intriguing but element mapping of a small areas (900*900µm) demonstrates large variability not only perpendicular to the lamination but also shows laterally limited features, such as inhomogeneous pyrite distribution and components very rich in vanadium (see Fig. 5.10). Nevertheless, this preliminary results are promising and further investigations, for instance by electron microscopy and high resolution studies on recent sediments, might shed light on mechanisms of diagenetic Mo fixation and even Mo sequestration within a multielement framework. The elevated Th/U ratios are mainly controlled by Th concentrations and do not indicate less reducing conditions or U remobilization, especially since U contents remain essentially constant. It can be assumed that high Ba concentrations indicate periods of elevated productivity which consequently causes enhanced sulphate-reduction and free H2S in the water column scavenging dissolved Mo. This suggests a dynamic environment switching between periods of high surface productivity and sulphidic water masses causing bioessential tracemetals to become limiting nutrients over a relatively short time span.

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Figure 5.10: A) Element map showing intensities of Fe occurrence which is predominantly incorporated in pyrite. B) Element map of the same area indicating V occurrence. Due to the relatively high detection limit of the electron probe microanalyser (ca. 1500 ppm), only exceptionally high V accumulation can be discerned, such as a highly enriched ‘pebble’ (red circle).

5.2.5. The Miaohe Member at Baiguoyuan, Hubei Province: A comparison

5.2.5.1. Results

Another well exposed outcrop of the Doushantuo Miaohe Mb. is located at Baiguoyuan, south of Jiulongwan on the eastern flank of the Huanglian Granite (see Fig. 3.2). The Miaohe Mb. is about 14m thick and has been sampled and geochemically analysed by Wallis (2006). The sedimentology of the succession presented in figure 5.11 is similar to the Miaohe at Jiulongwan but tends to have sandier black shales, in particular towards the upper part, and beds of silty dolomite are common. The TOC content is very high at the base (6.2%), decreases shortly before gradually rising again from 2.1 to 4.9% at the top. TS concentrations are below 0.2% throughout the Miaohe Mb. and correlate with very high Ba concentrations which attain a maximum of 1.3% but not with the low Fe concentrations of between 1 and 2.8%. Mo contents

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remain between 4 and 45.7 while very high variations are seen for V concentrations which are 873 ppm at the base and have several peaks within the middle part of up to more than 1% (detection limit is at 9999 ppm) before decreasing again and reach 893 ppm on top of the Miaohe black shale. U concentrations as well tend to be lower at the base and the top while significant variations are seen in the middle part with a maximum of 23.3 ppm. There is a good correlation between V and U (R2 = 0.71), a weak correlation between V and Mo (R2 = 0.29) and a moderate correlation between Mo and U (R2 = 0.46). TS and TOC show no correlation with Mo, V or U. Mo/TOC and V/TOC ratios have been generated for samples with more than 1% TOC which lead to a maximum of 17.3*10-4 for Mo/TOC within the upper part of the black shale and 3076.6*10-4 for V/TOC in the middle of the black shale. Th/U ratios are relatively high at the base of the Miaohe Mb. with a ratio of 4.5 and gradually decrease to ratios close to 1. V/(V+Ni) ratios are mainly above 0.93 with one exception (0.84) within a carbonate bed.

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Figure 5.11: The geochemical profile of the Miaohe Mb. at the Baiguoyuan section recorded by Wallis (2006). Dashed lines indicate lower sampling resolution than indicated on the stratigraphic column and where concentrations significantly exceed values found at Jiulongwan (see Fig. 5.4) the scale has been adjusted and labels are in bold.

5.2.5.2. Discussion

The Baiguoyuan section is characterized by another unusual geochemistry and previous studies at Baiguoyuan have mainly focussed on the black shale hosted Ag-V ore deposit, generally thought to be of sedimentary-diagenetic origin (Chao and Fapeng, 1986; Qian et al., 1995; Zhuang et al., 1999). While TOC contents are within the same range at Jiulongwan, the Miaohe Mb. at Baiguoyuan is poor in TS which is likely to be mainly bound as barite. Comparing the covariation patterns of TOC and TS concentrations from the Miaohe Mb. at Maoshi, Jijiawan, Jiulongwan and Baiguoyuan (see Fig. 5.12), it can be observed that the TS vs. TOC covariation is significantly different at Baiguoyuan than in other Miaohe black shales which present values within a similar range. Sediments depleted in S with respect to TOC have previously been 169

interpreted as being non-marine (Berner and Raiswell, 1984) but the abundance of other redoxsensitive trace-elements suggests otherwise. Although Mo is still slightly enriched at Baiguoyuan with respect to average shale (or UCC) values, Mo concentrations do not exceed a tenth of the maximum content reached at Jiulongwan. On the other hand, V attains concentrations up to more than 1% at Baiguoyuan, which is about 5 times more than the maximum at Jiulongwan. Hence, there seem to be a strong geochemical gradient between the depositional environments at Jiulongwan and Baiguoyuan leading to a disparity between respective V/TOC ratios within the Miaohe Mb., particularly with respect to coeval Mo/TOC ratios. However, U concentrations are very similar within the Miaohe black shale at both sections, with an average of 15.8 ppm at Jiulongwan and 16.1 ppm at Baiguoyuan. A better estimate of authigenic U is given by correcting for detrital U input using the calculation U aut = Utotal – Th/4 (see chapter 2.2.2.) and although Th contents at higher at Bayguoyuan, U aut remain within a similar range at both sections (average of 12.9 ppm at Jiulongwan and 8.4 ppm at Bayguoyuan). Since authigenic U enrichment takes primarily place within the sediments and is decoupled from the amount of free H2S in the water column, this leads to the suggestion that besides redox stratification, the biogeochemical cycling of sulphur played a crucial role in controlling the removal of Mo in combination with sulphide into the sediment, such as at Jiulongwan, and V together with elevated barite concentrations at Baiguoyuan. In summary, while the availability of redox-sensitive trace-metals was geographically restricted at Maoshi and Jijiawan during the deposition of the Miaohe Mb., the redox conditions were broadly similar to Jiulongwan with euxinia clearly expressed at Maoshi and Jiulongwan. The depositional environment at Baiguoyuan and Jiulongwan were presumably subject to similar trace-metal availability but separated by a chemocline which limited sulphatereduction and lead to preferential V over Mo mineralization at Baiguoyuan. Furthermore, it has been demonstrated that barite accumulation significantly depends of water-depth whereby detrital dilution and reductive dissolution tends to overprint primary Ba precipitation in shallow water environments and leads to greater enrichment in the deep sea (Von Breymann et al., 1992; Brumsack, 2006). Hence, the Miaohe Mb. at Bayguoyuan might have been deposited in a

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deeper portion of the Yangtze Platform maybe even beneath a sulphidic wedge such as proposed by Li et al. (2010).

Figure 5.12: Covariation patterns of TS vs. TOC from 4 different outcrops of the Doushantuo Miaohe Mb. Note that most values remain within an area above normal marine conditions (e.g. Berner and Raiswell, 1983) except for the Miaohe Mb. at Baiguoyuan were TS is significantly depleted with regard to TOC.

5.2.6. The Dengying and Liuchapo formations

5.2.6.1. The geochemical profile at Wuhe (Shibantan Mb. of the Dengying Fm.)

At Wuhe, one sample from the uppermost Doushantuo Fm. and parts of the Shibantan Member of the Dengying Fm. have been analysed (see Fig. 5.13). The one sample from the Doushantuo reproduces element concentrations similar to the Jiulongwan section, which is not surprising due to the close vicinity of both sections in the Three Gorges Area (see Fig. 3.2). The Shibantan Mb. is predominantly composed of limestone with over 10% inorganic carbon and hence, due to significant dilution, very low trace- and major-element concentrations come as no surprise. The normalization of redox-sensitive trace-elements to Sc might represent a more accurate account of their respective depletion or enrichement but to very low Sc concentrations below detection limit, element/Sc ratios exhibit a very different pattern 171

compared to concentration profiles but are meaningless in this case. Nevertheless, TOC contents of 1.7 and 2.6% are found at the base of the Shibantan limestone with little notable effect on TS and trace-metal concentrations although trace amounts of TOC further up correlate relatively well with trace-amounts of V, Mo, U, Ni, Cu, Mn, Ba and TS. Th/U ratios are very low, mostly due to Th concentrations below detection limit and V/(V+Ni) are between 0.57 and 0.76. Iron speciation analysis shows variable FeHR/FeT ratios between 0.24 and 0.79 but only very low FeT concentrations of below 0.1% are found within the Shibantan Mb.

Figure 5.13: Geochemical profile through the Dengying Fm. at Wuhe. The one sample from the uppermost Doushantuo Fm. invariably shows higher contents in redox-sensitive elements except for TOC. Normalizing them to Sc might represent a more accurate account of their respective depletion/enrichment but Sc contents are often below detection limit within the upper part of the Wuhe section which leads to unrealistically high V/Sc ratios (dashed interval is not to scale).

5.2.6.2. The Huanglian section (Liuchapo and Jiumenchong formations)

The sampled interval at Huanglian consists of two black shale samples from Doushantuo Fm. and a continuous profile across the Liuchapo/Jiumenchong boundary. The two samples from the Doushantuo Fm., although stratigraphically poorly controlled, show TOC contents of 172

up to 3.1% and most probably belong to the upper part of the formation (see Fig. 5.14). A relatively high Mo concentration of 59 ppm and high V content of 1977.7 ppm together with depleted Ni and Cu concentrations support this interpretation. The silicified shales of the sampled Liuchapo succession all show very low concentrations of redox-sensitive trace-metals along with low Fe, Mn and Ba and, in particular, low TOC and TS contents. Across the Precambrian - Cambrian boundary, within the lowermost black shales of the Jiumenchong Fm., TOC contents increase to above 9% while TS remains relatively low at below 1%. 1-2m above the boundary, the V concentration increases to 9859.5 ppm before falling again to 3654.3 ppm 1m above. Mo gradually increases and attains 96.3 ppm on top of the sampled section. A Mo/TOC ratio of 19*10-4 is seen within the Doushantuo Fm. while the lower part of the Jiumenchong black shales is characterized by a gradual increase to up to 10.1*10-4. V/TOC ratios are high within the Doushantuo interval but reach their maximum of 1049.9*10-4 at the base of the Jiumenchong Fm. Ni concentrations, with a maximum of 241 ppm, follow the concentration profile of V while Cu and other redox-sensitive redox-metals remain generally depleted. Ba increases into the percent range up to 1.3% in the lower Jiumenchong. V/(V+Ni) ratios vary between 0.8 and 0.99 throughout the section. Fe concentrations are very low in all samples and, except for 1.2% in one sample from the Doushantuo Fm., all below 0.7% and decrease within the upper Liuchapo Fm. before rising again at the base of the Jiumenchong Fm. P contents are depleted throughout the section with a maximum of 557 ppm within the Doushantuo Fm. and track Fe concentrations. Iron speciation data must be treated with caution, especially since a FeHR/FeT ratio as low as 0.18 is found at the base of the Jiumenchong Fm. Sulphide isotopes have only been measured in two samples, one from the Doushantuo Fm. and one from the Liuchapo Fm., and both have negative values of -4.3‰ and -6.3‰ (VCDT) respectively.

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Figure 5.14: Geochemical profile across the Liuchapo/Jiumenchong boundary at Huanglian, likely to be equivalent to the Precambrian – Cambrian boundary. Note that the two samples at the base of the section are from the uppermost Doushantuo Fm. without precise stratigraphic control.

5.2.6.3. The Longbizui section (Liuchapo and Jiumenchong formations)

Within the predominantly cherty shales and chert beds of the Liuchapo Fm. a black shale interval is found where TOC and TS concentrations both attain over 3.1% within a thin horizon while Mo and U remain depleted and V is only slightly enriched to concentrations up to 338.8 ppm (see Fig. 5.15). Other trace-metals such as Ni and Cu are strongly depleted while Ba concentrations reach a peak of 2438.2 ppm. FePy/FeHR ratios exceed 0.7 within an interval of 15cm just below and within that organic-rich horizon. Predominantly positive δ34SPyrite values attain a minimum of -0.38‰ (VCDT) 50cm below this horizon and are highly variable for the next few dm and reach 15.1‰ within the organic rich horizon itself. The following, predominantly cherty shales of the Liuchapo Fm. are characterized by TOC and TS contents under 1% and depleted trace-metal concentrations. In the overlying dark cherts and carbonate beds a significant increase in Ba concentrations to up to 2269.2 ppm takes place until the onset of the black shale succession at the Liuchapo/Jiumenchong boundary and decrease again in concert with strongly increasing trace-metal concentrations. V increases to 1936.8 ppm at the base of the black shale and decreases again within a few meters while Mo and U concentrations are still increasing to 107 and 51.6 ppm respectively before they fall again further up on top of 174

the sampled black shale, broadly tracking TOC and TS contents. TS contents correlate well with pyrite S although variable amounts of non-pyrite S averaging 50% of TS are observed. Fe concentrations vary between about 0.5 and 2.5% in the lower black shale horizon within the Liuchapo Fm. and remain relatively low further up until they increase again within the Jiumenchong black shales with a maximum of 3.6%. Mo/TOC ratios are low prior to the Jiumenching Fm. where they reach values between 7 and 15.8*10-4. V/TOC ratios on the other hand show a maximum of 553.4*10-4 just below the Jiumenchong black shales and decrease to low values between 26.4 and 189.5*10-4 further up. The maximum Mn concentration of 221 ppm is found just above the thin organic-rich interval and rapidly decreases to very low contents until a rise is seen again within the black shales. FeHR/FeT ratios indicate anoxic conditions throughout the section and FePy/FeHR ratios between 0.7 and 0.8 suggest pronounced sulphidic conditions during extended intervals within the Jiumenchong black shale. Sulphide isotope values remain positive throughout the section,

34

S being enriched in

34

S by

between 9.3 and 29.6‰ (VCDT).

Figure 5.15: The geochemical profile across the Precambrian – Cambrian boundary at Longbizui. The dataset including Mo, V, U, Sc, V and Ni has been kindly provided by Xi Chen (Nanjing University). 175

5.2.6.4. Discussion

The Longbizui section, our most complete Liuchapo/Jiumenchong boundary section, equivalent to the Precambrian – Cambrian boundary in the slope and basinal areas of the Yangtze Platform, records two euxinic events as indicated by iron speciation. The first one is indicated within a very limited interval of about 1m within the Liuchapo Fm. and a second one during the deposition of the massive black shale succession of the Jiumenchong Fm. ca. 30m above. The concentration of redox-sensitive trace-elements Mo and U remain low during the first euxinic interval but minor perturbations are observed for V, Fe, Mn, Ba and TOC contents, during the interval or right above. Although Mn concentrations attain a maximum just above the interval, concentrations are still significantly depleted as would be expected in a reducing environment and the fluctuations might be due to diagenetic remobilization and precipitation of trace-amounts of Mn-carbonate at a short-lived redoxcline. Higher V and Ba concentrations coincide with the significant increase in TOC contents within the euxinic interval due to their affinity to be fixed in the sediment in association with organic matter. The formation of significant amounts of pyrite is exemplified by comparatively elevated TS and Fe concentrations on top of the interval and coincides with highly variable sulphide isotope values whereby some are close to 0‰ and represent the lowest values found throughout the Longbizui section. This suggests episodic increases in seawater sulphate concentrations which caused euxinia to develop rapidly in an otherwise Fe(II)-limited environment. In other words, the sedimentary succession at Longbizui was deposited within a geochemically sensitive environment where minor changes in sulphate concentrations and/or organic matter delivery to the seafloor could trigger sulphidic conditions. Within the upper black shale succession, TOC contents increase alongside redoxsensitive trace-metals, TS and Fe. While Mo and U concentrations remain enriched within the same range, V decreases soon afterwards but remains slightly enriched during the euxinic interval. The Ba enrichment within the chert beds underneath the black shales of the Jiumenchong Fm. might be used as a proxy for productivity in the photic zone as it can be assumed that sulphate-reduction did not lead to significant barite dissolution (e.g. van Os et al.,

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1991; Torres et al., 1996). Thus, enhanced productivity during the Early Cambrian could have induced anoxic conditions and organic matter preservation in the deep sea which might have caused a rapid drawdown of V after an initial increase and enhanced sulphate-reduction would have remobilized Ba and ultimately lead to sulphidic conditions. Because Mo removal and fixation within the sediment mainly depends on significant concentrations of free H 2S (e.g. Helz et al., 1996), one could hypothesize that reducing, anoxic environments were widespread at that time but euxinic only locally developed, which did not lead to a significantly depleted Mo reservoir during that time, additionally suggested by the undisturbed increase of Mo/TOC ratios. δ34SPy values remain positive but are inversely proportional to TS contents within the Jiumenchong black shale succession, indicating that fluctuating sulphate levels might have been decisive for the development of euxinia during a time of low seawater sulphate (see also above). However, several studies suggest low sulphate concentrations in the ocean of not more than 12 mM during most of the Precambrian until the late Neoproterozoic (see chapter 1.4; Shen et al., 2003; Canfield et al., 2004; Kah et al., 2004; Hurtgen et al., 2005; Johnston et al., 2006; Canfield and Farquhar, 2009; Ries et al., 2009), they are thought to have risen to values as high as 16mM during the Precambrian – Cambrian transition (Brennan et al., 2004). This makes sense when we consider that the black shales at the base of the Cambrian on the Yangtze Platform have often been deposited in a euxinic environement while ferruginous conditions probably dominated during the Neoproterozoic (Canfield et al., 2008; Poulton and Canfield, 2011). The apparent uniqueness of euxinic conditions on the Yangtze Platform indicates strong spatial variations in the timing of the oxygenation of the deep sea, where sulphide oxidation, possibly enhanced by the emergence of bioturbation (Canfield and Farquhar, 2009), led to globally increasing seawater sulphate concentrations and subsequently to enhanced sulphatereduction which regionally lead to increasing free H2S concentrations in the water column of the Yangtze Platform. Considering the pronounced euxinic conditions occurring during the deposition of the Miaohe Member of the Doushantuo Fm., we could hypothesize a gradual increase in oceanic sulphate levels causing euxinia on the shelf margin only (Li et al., 2010) which later, during the earliest Cambrian, developed towards the deeper portions of the basin. Alternatively, enhanced primary productivity and increasing export of organic matter to the

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deep sea might have played an important role in fuelling sulphate reduction. Increased primary productivity could have caused the very high Ba contents found within the base of the Jiumenchong Fm. at Huanglian (Brumsack and Gieskes, 1983; Brumsack, 1986, 2006; Dymond et al., 1992; Tribovillard et al., 2006). The Precambrian – Cambrian boundary section at Huanglian, ca. 70km southwest of Longbizui, exhibits a very similar geochemical profile regarding redox-sensitive trace-metals with rapidly increasing TOC, TS, Mo and V concentrations at the lowermost Jiumenchong black shale whereby V contents are rapidly falling afterwards. One major difference is that V concentrations attain almost 1% at Huanglian, which is about 5 times more than the maximum concentration measured at Longbizui while V/Sc ratios are even more than 10 times higher. V concentrations around and above 1% within basal Cambrian black shales deposited at deeper sections of the Yangtze Platform have been reported in other studies (Wallis, 2006; Guo et al., 2007). Along with an overall metal enrichment, the increase of Ba concentrations up to more than 1.3% is striking but agrees well with the occurrence of numerous Early Cambrian bedded barite deposits associated with black shales along the outer shelf parallel to the platform margin and along the northern border of the Yangtze Platform (see Fig. 5.16; Chen and Gao, 1984; Wang and Li, 1991; Maynard and Okita, 1991). The unusually abundant witherite (BaCO 3) deposits occurring in Early Cambrian successions on the northern platform, which has not been investigated during the present study, have been interpreted as result of seawater sulphate depletion in conjunction with very high Ba concentrations (Lydon et al., 1985; Maynard and Okita, 1991). The high amount of non-pyrite sulphur within the Ba enriched horizon is enough to account for the sulphate that would be bound to 1.3% Ba (eq. to 2.2% BaSO 4). Iron speciation analysis shows that contrary to the Jiumenchong black shale at Longbizui, euxinia was never reached at Huanglian and the high V enrichment, especially compared to Mo, indicates a dysoxic environment where sulphate-reduction played a minor role and thus barite could be preserved. A situation broadly similar between the Miaohe Mb. deposited at Jiulongwan and Bayguoyuan (see chapter 5.2.5.2.), where differences in paleo-depth have been suggested, meaning that Huanglian was deposited in deeper parts of the slope or basin with respect to Longbizui.

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However, the use of Ba concentrations and barite abundance as paleoproductivity proxy has to be critically appreciated and even if sulphate-reducing conditions were not attained, high Ba enrichment might result from early diagenetic remobilization and, Ba migration through pore waters and re-precipitation where more oxidizing conditions are met (Van Os et al., 1991; Torres et al., 1996), a behavior similar to Mn with which Ba can be involved (Dymond et al., 1992). Nevertheless, the very high TOC contents of above 9% at Huanglian might indicate that Ba can be used as a paleoproductivity proxy more confidently, especially since Mn concentrations show no correlation with Ba and both elements tend to exhibit mirroring concentrations profiles throughout the section. But from a qualitative point of view, considering the overall abundance of barite deposits on the Yangtze Platform, a significant increase in seawater sulphate concentrations and primary productivity is strongly suggested.

Figure 5.16: Localities of the principal bedded barite deposits on the Yangtze Platform (modified from Wang and Li, 1991) from which the sections of Huanglian and Longbizui are slightly offset to the northwest.

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5.3.

The Early Cambrian

5.3.1. The Early Cambrian in the Three Gorges Area (Shuijingtuo and Yangjiahe formations)

5.3.1.1. The redox geochemistry during the Early Cambrian at the Jijiawan section

At Jijiawan, the lower Shuijingtuo has been sampled without precise stratigraphic control. However, TOC and TS contents increase stepwise towards the black shale and attain 5.8% TOC and 5.1% TS (see Fig. 5.17). There is moderate covariation between the high TOC and TS concentrations within the upper black shale, which averaging 5.1% and 3.5% respectively. TS and pyrite S correlate reasonably well although variable amounts of non-pyrite sulphur are observed, with maxima coinciding with high Ba contents of up to 4723.8 ppm. Mo and V concentrations show respective maxima of 212.8 ppm and 909.9 ppm within the lower black shale interval, where U contents also peak at 47.2 ppm. Whereas Mo and V concentrations decrease and stabilize around 40 ppm for Mo and 170 ppm for V within the upper black shale, U concentrations are more variable between 26.2 and 53.2 ppm. Ni concentrations show a broadly similar enrichment pattern whereas Cu is depleted throughout the section. Mo/TOC ratios remain below 10*10-4 throughout the section except in the metal-enriched horizon where they reach 36.4*10-4. The V/TOC ratios behave similarly across the profile with a maximum of 155.8*10-4. All redox-sensitive trace-metals show exhibit moderate to good correlation with TOC contents and moderate correlation with TS contents. Fe contents fluctuate between 0.3 and 2.3% prior to the onset of the black shale where a maximum of 3.5% is seen at the base and tend to decrease up-section but mostly remain above 2%. Mn is significantly depleted showing a maximum of 758.5 ppm within the same layer where U contents attain their maximum. Th/U ratios remain well below 1 and V/(V+Ni) values are highly variable below the black shale successions and remain between 0.5 and 0.68 within the overlying Shuijingtuo black shales. Iron speciation data shows high proportions of highly reactive iron with Fe HR/FeT ratios close to 1 throughout the section while FeT concentrations are more variable and show low values of below 0.4% below the black shale successions where concentrations between 180

2.25 and 3.51% are found. FePy/FeHR ratios have an average of 0.68 across the section whereby the lowest values are observed at the onset of the black shale intervals with a minimum of 0.56. There is a lack of sulphide isotope measurement and the only value of 18.6‰ (VCDT) has been obtained from a sample at the base of the sampled section underneath the black shales.

Figure 5.17: The geochemical profile analyzed from the Early Cambrian Shuijingtuo Fm. at the Jijiawan section. The yellow shaded intervals represent euxinic conditions as indicated by iron speciation.

5.3.1.2. The redox geochemistry during the Early Cambrian at the Wuhe section

At Wuhe, most of the Yangjiahe Fm. is poor in organic matter and redox-sensitive traceelements (see Fig. 5.18). Within the phosphatic layer at the boundary to the overlying Shuijingtuo Fm., TOC contents increase to 2.3% together with the maximum V concentrations of 262.8 ppm. Other elements increase as well but reach their maximum more gradually further up. U reaches a maximum concentration of 119.3 ppm 1m above before decreasing again and 181

Mo peaks 4m above with 36.5 ppm, staying within the same range for the rest of the sampled section. The maximum Mo concentrations coincide with maximum TOC and TS contents of 3.4 and 4.4% respectively, a second peak in V content of 163 ppm, a maximum Ba concentration of 2570 ppm and peaks in Ni and Cu, although significant enrichment is not given. Fe concentrations are low within the Yangjiahe Fm. and peak at 3.5% within the black shale of the Shuijingtuo Fm. Mn contents show depleted values with a maximum within the Shuijingtuo black shale of 413 ppm. Although most of the sulphur measured throughout the section is nonpyritic, a good correlation exists between TS and pyrite S. Correlations between TOC and other elements are moderate and, considering the restricted dataset for the Wuhe section, are not significant. Mo.TOC ratios reach a maximum of 31.5*10-4 within the black shale on top of the sampled section while V/TOC ratios are very low within the black shales. Th/U ratios are well below 1 throughout the section although values are higher within the Yangjiahe Fm. and drop in the Shuijingtuo Fm. V/(V+Ni) values are variable and tend to be very low within the Shuijingtuo Fm. with a minimum of 0.32. The FeHR/FeT ratios are high with a minimum of 0.66 in the uppermost sample and FePy/FeHR ratios show a maximum of 0.71 just below the Yangjiahe/Shuijingtuo boundary. Sulphide isotopes show values below 10‰ (VCDT) until about 5m below the formations boundary and increase to values around 20‰ below the boundary around the interval with the highest FePy/FeHR ratios. After the Yangjiahe/Shuijingtuo boundary, δ34SPyrite values decrease again and are between -4.9 and 0.1‰ (VCDT) within the lower Shujingtuo Fm.

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Figure 5.18: The geochemical profile across the Yangjiahe/Shuijingtuo boundary at the Wuhe section.

5.3.1.3. Ocean chemistry and platform evolution during the Early Cambrian: The sequel

Although the stratigraphic correlation between the Early Cambrian Jijiawan and Wuhe sections is not straightforward, the enrichment pattern of the redox-sensitive trace-metals Mo, V and U are similar although with major differences in the extent, timing and the relative enrichments when compared to each other. While maximum Mo and V concentrations are between 5 and 10 times higher within the base of the Shuijingtuo Fm. at Jijiawan compared to Wuhe, it is the other way around when considering U concentrations, where maximum values are more than double at Wuhe compared to Jijiawan. At Jijiawan, the peak in Mo, V and U concentrations within the lower part of the Shuijingtuo black shale are coeval but while V contents return to values close to average shale (or UCC), Mo decreases as well but to values still significantly higher than in average shale and U remains within the same elevated range and even slightly increases further up in the black shale. One likely explanation is that euxinia 183

only marginally developed during the deposition of the Shuijingtuo black shale at Wuhe but happened to be pronounced at Jijiawan and that sulphidic conditions were the driving force in the removal of Mo from the water column and the preservation of organic matter along with associated V. Ba and Mn concentrations correlate well at the Wuhe section which can be illustrates the sometimes observed association between this two elements, probably caused by the remobilization of Ba alongside the reductive dissolution of Mn-oxyhydroxides which can lead to concomitant Ba enrichment when Mn-oxyhydroxides reprecipitate at the redoxcline (e.g. Dymond et al., 1992). At Jijiawan, maximum Ba concentrations are found within the short interval with low FePy/FeHR which would additionally support minor sulphate-reduction. Considering the study on the Doushantuo Fm. at the Jijiawan and Jiulongwan sections, the latter being close to Wuhe, an extended geochemical profile through the episodically occurring black shale successions can illustrate the dynamic changes in the biogeochemical cycling of redox-sensitive trace-elements and the coeval changes in the prevailing water column redox conditions (see Fig. 5.19). Iron speciation analysis shows that intermittent suphidic conditions were common throughout the Precambrian – Cambrian transition at Jiulongwan but only appeared during the Early Cambrian at Jijiawan. While most of the analysed geochemical parameters differ significantly between Jiulongwan and Jijiawan during the deposition of the Miaohe Mb., we find similarities around the Early Cambrian Yangjiahe/Shuijingtuo boundary such as an increase of Mo/TOC ratios within the same range. It appears as if significantly increasing concentrations of dissolved redox-sensitive trace-metals and sulphate determined ocean chemistry at the end of the Doushantuo Fm. before 551 Ma leading to very high tracemetal accumulation and negative sulphide isotope signatures.

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Figure 5.19: Schematic stratigraphic profile as it appears in the Three Gorges Area, Hubei Province, with a considerably shortened Dengying Fm. for better display. The reddish shaded intervals indicate anoxic-ferruginous conditions and the yellow shaded intervals suggest a euxinic depositional environment.

However, during the Early Cambrian, the Jiulongwan (Wuhe) and Jijiawan depositional environments seem to have been connected and enjoyed similar seawater chemistry caused by the Yangtze Platform approaching open shelf geometry (see Fig. 5.6b). The more distally deposited Early Cambrian black shales at Huanglian and Longbizui as well exhibit Mo/TOC ratios

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and sulphide isotope values similar to the sections around the Three Gorges Area and point to widespread euxinic conditions from the platform shelf down to the basin which consequently gave rise to increased pyrite burial and sulphate limitation. The increase in bio-available Mo and V in a dominantly ferruginous ocean might have triggered unprecedented primary production and organic matter delivery to the ocean floor, which on the one hand created conditions favourable for intensified sulphate-reduction and the diagenetic remobilization of Ba which reprecipitated as barite in deeper portions of the ocean (see chapter 5.2.3.), accelerating the seawater sulphate drawdown and suggesting non-euxinic conditions below an extended wedge of free H2S reaching towards the open ocean (see Fig. 5.20). However, a steady source of sulphate must have sustained euxinia and concomitant barite deposition over an extended amount of time. Canfield and Farquhar (2009) demonstrated that the emergence and intensification of bioturbation during the Precambrian – Cambrian transition (Martin et al., 2000) would have caused a several fold increase in seawater sulphate concentrations and initiated the extensive deposition of evaporite minerals throughout the Phanerozoic.

Figure 5.20: Open shelf model showing how an enhanced source of sulphate to the water column would have widened a sulphidic wedge while sulphate-reduction played a minor role in the deeper parts of the ocean and thus allowing the accumulation of bedded barite deposits. A constant source of sulphate would have been required to sustain widespread euxinia and barite deposition which probably arose after the emergence and intensification of bioturbation (Canfield and Farquhar, 2009).

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5.3.2. The Zhongnan section (Niutitang Formation): A highly condensed succession on the platform margin

5.3.2.1. Geochemical analysis

The sampled succession can be broadly subdivided into two parts (see Fig. 5.21). The lower part is predominantly composed of phosphate, with P contents of up to 15%, and poor in organic carbon (mostly less than 1%) and silicate (less than 20%). The upper part is composed by a black shale succession with high TOC content of up to 11%. The sulphide ore horizon is situated right above the lower phosphatic part and highly enriched in Fe, Mn, Cu, Ni, Ba, Zn and Mo but only Mn, Cu, Ni, Ba and Zn reach their maximum within this layer. Mo/TOC exhibits a prominent maximum peak at the sulphide ore layer while V/TOC is relatively high throughout the phosphorite until beyond the sulphide ore layer and varies considerably between 0 and 1600 within the remaining succession. Fe reaches its maximum of 16.1% about 15 cm above together with a peak in sulphur concentration. Although TS and pyrite S contents correlate very well throughout the section, there is significant non-pyrite S occurring within the ore layer which can be attributed to other metal sulphides. 5 cm above, TOC reaches its first peak with a concentration of 9.65%. With TOC, there is a concomitant rise in V content and a minor increase in Mo, Cu and Ni while Fe concentrations are very low again, down to around 1% and less. The decrease in TOC to below 2% 20 cm above is accompanied by a second peak in Cu, Mo and to a minor extent Zn content, and the first peak of V. 70 cm above, V decreases again to 487.3 ppm while other trace-metals show low and even depleted concentrations. The maximum TOC value within the recorded Zhongnan section of 11.08% is measured 35cm above and accompanied by concomitant peaks in Cu, Ni, Zn, Cr, Mo and V. The remaining 1.5m show an initial decrease in Mo and V before both concentrations rise again. There is an overall decrease in Cu, Ni and Zn and a slight increase in Ba in the uppermost 1.5m of the section. Mo/TOC ratios are extremely high within the ore horizon which is mostly due to very low TOC contents which mainly below 1%. Within the overlying black shales, Mo/TOC ratios are

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relatively high with a peak of 48.5*10-4. V/TOC ratios exhibit a similar pattern and correlate well with Mo/TOC ratios within the black shale above the ore layer (R2 = 0.85). V/(V+Ni) varies between 0.75 and 0.99, exception made for a particularly low ratio of 0.42 within the sulphide ore layer. Iron speciation data shows a relatively low Fe HR/FeT ratio of 0.37 within the sulphide ore layer among generally high values which decrease upwards to values down to 0.3. FePy/FeHR ratios reach values of over 0.8 just above the ore layer. Sulphide isotopes were measured for an interval of 20cm and show positive values above 4‰ (VCDT) including the sulphide ore layer where values peak at 11.1‰ (VCDT).

Figure 5.21: The geochemical profile of the condensed Early Cambrian sedimentary succession at Zhongnan.

5.3.2.2. Discussion

The phosphorite P reaches the sediment via the deposition of organic material and is released as PO 43during reductive dissolution of Fe-oxyhydroxides and/or organic matter remineralisation and it either escapes back to the water column or precipitates within the sediment (e.g. Span et al., 1992; Louchouarn et al., 1997; Kidder et al., 2003; Sannigrahi and Ingall, 2005; Ruttenberg, 2003). Bacterial mediation plays a significant role in phosphogenesis, especially through sulphate reduction and fermentation (e.g. Tribovillard et al., 2006; Papineau, 2010). Under 188

anoxic conditions, P usually diffuses upwards from the sediment to the water column where it can return to the photic zone and further stimulate primary production or its concentration increases in the anoxic zone (Ruttenberg, 2003). P cycling being very efficient, Benitez-Nelson (2000) estimated that only 1% of organic P remains trapped within the sediments. Under certain conditions, mainly controlled by alkalinity, pH, Eh and bacterial activity (e.g. BenitezNelson, 2000), P remains in the sediment and authigenic P minerals can precipitate, principally apatite which explains the excellent covariation with Ca in our section. High P concentrations can be achieved by high organic matter supply but also in association with the redox cycling of Fe (Piper and Perkins, 2004; Algeo and Ingall, 2007) or Mn (Wang and Van Cappellen, 1996) and are therefore not necessarily indicative of a high organic matter flux (Tribovillard et al., 2006). In oxic environments, redox-cycling of Fe limits the diffusive flux of remineralized P to the surface and Fe-oxyhydroxides retain P within the sediment allowing enough time for the slow growth of authigenic P phases. In permanently anoxic environments with sulphidic bottom waters, Fe-oxyhydroxides do not precipitate within the sediments and P is therefore less likely to be retained. In order to form highly enriched phosphorite deposits such as in the Zhongnan section, hydrodynamically induced winnowing of sediments usually plays an important role. The extraordinary widespread occurrence and abundance of Early Cambrian phosphate deposits worldwide (Cook, 1992) are pointing to major changes in the biogeochemical cycling of phosphorus and are likely to pinpoint the transition from elevated oceanic P concentrations in the Precambrian to lower lower levels in the Phanerozoic (Planavsky et al., 2010), which together with favourable paleoceanographic constellation lead to these massive phosphorite formations.

The Ni-Mo sulphide ore horizon

The black shale associated Ni-Mo sulphide ore, which can contain Mo concentrations of up to several percent, has been reported from several locations along the platform margin within transgressional and highly condensed facies (Coveney and Chen, 1991; Lott et al., 1999; Steiner et al., 2001; Lehmann et al., 2007; Wille et al., 2008; Pašava et al., 2008; Chen et al.,

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2009; Wen and Carignan, 2011). Although metalliferous black shale successions are particularly common during the Precambrian-Cambrian transition (e.g. Pašava et al., 2003; Lyons et al., 2006), the particular association of metals, including such anomalous enrichment in Mo, has provoked much controversy about the mechanism behind the origin of the Ni-Mo sulphide ore layer on the Yangtze Platform. While some advocate a sedimentary-exhalative (SEDEX) origin (Lott et al., 1999; Steiner et al., 2001; Pašava et al., 2004), others concluded that the metal enrichment derived directly from seawater (Mao et al., 2002; Lehman et al., 2007). At Zhongnan, not all trace-metals are enriched within the ore horizon itself, i.e. Pb, Cr and V show higher concentrations within the phosphorite and above the ore layer where they are relatively depleted. This might on the one hand be related to the “open” structure of apatites, which allow many elements to substitute for Ca, PO4 and F (e.g. Prévôt and Lucas, 1980; Jarvis et al., 1994; Tribovillard et al., 2006). However, it is difficult to explain why these particular elements have been enriched and not others, such as Zn and Mo, although they are likely to be affected by this substitution process as well. Nonetheless, the enrichment of Pb, Cr and V above the ore layer is concomitant with an almost two magnitude increase in TOC which might also have led to higher concentrations of other metals, in particular Fe and Ni. Ni and Cu are predominantly delivered to the sediments in association with organic matter (Tribovillard et al., 2006) but only Ni exhibits a good covariation with TOC when the extremely high Ni content within the ore layer is excluded. The Mo vs. TOC plot exhibits no correlation at all and where sulphidic conditions are indicated through high FePy/FeHR ratios, low TOC and moderate Mo contents represent somewhat counterintuitive results. Furthermore, the highest Mo concentrations are found in layers with the lowest Fe HR/FeT. There is a good correlation between V and TOC concentrations prior to the increase of TOC contents to values above 2% but none within most of the organic rich black shales. This contradictory behaviour of the investigated geochemical parameters does so far not support a seawater origin for the metal-enriched horizon which is itself neither enriched in TOC nor pyrite. Instead, a suite of a metal-rich horizon (Fe, Mn, Ba, Cu, Ni, Zn, Mo) followed by a pyrite layer and finally by a high TOC layer is observed while other trace metals (Pb, Cr and V) are enriched within the phosphorite). Such a successive suite of different metal-enrichment has

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not been reported from other occurrences of this Ni-Mo sulphide ore horizon and it might as well represent an artefact which can arise from sampling or diagenetic mobilization and reprecipitation of redox-sensitive elements governed by steep redox-gradients.

5.3.3. The Xiaotan section

5.3.3.1. The redox geochemistry of its black shale successions

Due to the extended character of the sampled Xiaotan section, the results have been subdivided into three black shale succession, the 1st and 2nd at the base and top of the Shiyantou Fm. and the 3rd in the lowermost Yuanshan Fm., whereby the last one includes the overlying organic poor sediments sampled at lower resolution until the overlying Canglangpu Fm. 1st black shale (lower Shiyantou Fm.)

The first black shale succession at the base of the Shiyantou Fm. is about 36 m thick and shows appreciable TOC concentrations with a maximum of 5.02% at the base and averaging 2.92%, while TS contents remain very low with a maximum of little over 0.3% (see Fig. 5.22). Mo concentrations are also very low, remaining close to average shale values except within the first black shale sample where it reaches a value of 20 ppm. V concentrations on the other hand reach a maximum value of 2147.9 ppm, over 21 times the average shale value, and are relatively high in the middle part of this first black shale succession. Such as in most previously discussed black shale successions, normalizing Mo and V contents to Sc does not significantly alter the overall pattern. There is no covariation between Mo and V, while very high V values tend to occur in samples where Mo concentrations are very low. Mo/TOC ratios show a peak at the beginning of the succession and then gradually rise towards the upper part of the black shale. Mo and TOC are only weakly correlated with R2 = 0.36. V/TOC ratios can be relatively high and generally follow the same pattern as the V concentration profile. V correlates with

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TOC with R2 = 0.32. Fe contents peak at the base of the Shiyantou Fm., decrease shortly after to a minimum of 1.1% before an overall increasing trend across the black shale until Fe concentrations reach their maximum of 3.5% at the base of the overlying shales. P concentrations are highest (1%) within the boundary zone between the Dahai Mb. and the Shiyantou Fm. and remain variable for the next ca. 10m before stabilizing at lower values around 0.1% for the rest of the section. Mn contents show a maximum of 688.4 ppm at the boundary but decrease to low values between 40 and 200 ppm within the Shiyantou Fm., nonetheless describing a slightly increasing trend in concentrations, weakly mirroring Ba contents between a minimum of 384.7 ppm at the boundary and a maximum of 1310.2 ppm on top of the overlying black shale. The V/(V+Ni) yields values of mostly above 0.84. In this lowermost black shale succession, FeHR/FeT ratios remain above 0.38 but FePy/FeHR close to 0, therefore indicating an anoxic, ferrous-iron rich water column without any significant amount of free H2S. A gradual decrease in FeHR/FeT as we move towards the top of the black shale can be observed while FePy/FeHR ratios remain extremely low.

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Figure 5.22: The geochemical profile through the 1st black shale at the base of the Shiyantou Fm. at Xiaotan.

2nd black shale succession (upper Shiyantou Fm.)

The second black shale succession in the upper Shiyantou Fm. (XTY1-XTY30), with a thickness of about 39m, contains slightly lower TOC concentrations than in the previous black shale but sulphur contents are highly variable increasing to up to 1.52% in some layers within the upper half above a 2.5 m thick succession of more massive carbonate beds (see Fig. 5.23). Mo concentrations are still relatively low but slightly elevated in the upper part of the 2 nd black shale, attaining a maximum of 18.95ppm. Fe concentrations are highly variable between 1.4 and 4.4%, increasing irregularly towards the upper part of the black shale. Mn contents are very low and fluctuate around 130 ppm until the onset of strongly metal-enriched black shale beds where a concentration of over 0.5% has been found together with pronounced, major enrichment of Ni (up to 556.8 ppm) and Zn (up to 1345.6 ppm) along with Li (251 ppm), Be (19.4 ppm) and Sc (185.4 ppm). V is markedly less enriched compared with the 1 st black shale succession and does not exceed 306.4ppm. There is neither a correlation between Mo and V, nor between Mo and TOC, or V and TOC (see Fig. 5.24). Th/U ratios are mainly above 2 and V/(V+Ni) ratios average 0.82. An interesting feature is the very distinct peak in Ni concentrations, on top of the 2nd black shale, which increase from 36.5 to 285.5 up to 556.8 ppm before decreasing again to 28.1 ppm within only 3 m (see Fig. 5.25). FeHR/FeT values can be taken to indicate deposition under an anoxic-ferruginous water column although one value (0.36) is below the threshold of 0.38. FePy/FeHR remains low but some peaks are clearly visible, sometimes concomitant with low FeHR/FeT, indicating that the proportion of pyrite iron sometimes accounts for most of the highly reactive iron. Sulphide isotopic values are negative throughout, with a maximum of -3.7‰ (VCDT), and tend to decrease towards to metalenriched layer where a minimum of -17.5‰ (VCDT) is observed.

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3rd black shale succession and beyond (Yuanshan Fm.)

The black shale succession at the base of the Yuanshan Fm., with a thickness of about 10m, begins with high TOC contents of up to 4.74% which rapidly decrease to moderate values and finally below 1% after 10 m for the rest of the section (see Fig. 5.23). Sulphur contents on the other hand remain below 0.5% at the base and increase to a maximum of 1.16% in the TOC poor carbonate/shale sediments, leading to a bimodal TOC and S covariation pattern for the Yuanshan Fm. (see Fig. 24). The Mo concentration profile begins with a maximum of 39.24 ppm which rapidly decreases and very closely follows the TOC content with Mo (ppm) = 8.6 × TOC (%) and R2 = 0.98. V concentrations are slightly less well correlated with TOC (R2 = 0.67) and peaks a bit above the base of the Yuanshan black shale with 660.6 ppm. Vanadium decreases at a slower pace than Mo and shows greater variability throughout the succession while both, Mo and V, are correlated with each other with R2 < 0.6. U, contrary to the previous black shale successions, also shows a moderate correlation with TOC with R2 = 0.54. Fe concentrations increase at the onset of the black shale succession and reach a maximum of 5.3% after 3.3m and varies between 2.4 and 4.8% for the rest of the Yuanshan Fm. whereby minima correspond to maxima in Mn contents which fluctuate between a few hundreds to 2805 ppm and minima in Ba concentrations down to 644.6 ppm within the Yuanshan Fm.

Both, Mn and Ba

concentrations are otherwise uncorrelated to Fe contents. Mo/TOC ratios are higher than within the previous black shale successions but rather variable as well, peaking at a maximum of 20.47. V/TOC ratios are variable but show a gradual trend towards higher values at the top of the Yuanshan Fm. The redox proxy V/(V+Ni) decreases from 0.95 to 0.78 towards the top of the Yuanshan Fm. and Th/U ratios show higher values (to a maximum of 6.39) in the sediments above the black shales. The FeHR/FeT ratio reaches values below 0.38 within the upper black shale and persists until the end of the Yuanshan Fm. while pyrite iron increases to a maximum of 50% highly reactive iron within the carbonate/shale sequence above the black shale. δ 34SPy values are positive at the onset of the black shale succession with a value of 3.1‰ (VCDT) and decrease afterwards with some variations mostly within the negative range but with two

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positive peaks of 1.5 and 12.6‰ (VCDT) which correspond to pronounced minima in TOC, V, Fe and Ba concentrations and maxima in Mn concentrations.

Figure 5.23: The geochemical profile across the Shiyantou/Yuanshan boundary, until the overlying Canglangpu Fm. (CLP), showing the 2nd and 3rd black shale succession.

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Figure 5.24: Covariation patterns between some geochemical parameters divided in the three black shale successions seen within the Early Cambrian black shales at Xiaotan.

5.3.3.2. High resolution sampling: results and discussion The section sampled at higher resolution spanning part of the 1 st black shale at the base of the Shiyantou Fm. (XTS1-14) shows generally more variability in the analysed geochemical parameters than the section sampled within the 2nd black shale at the top of the Shiyantou Fm. (see Fig. 5.25). For XTS1-14, note that within 1.2 m, TOC fluctuates between 2.53 and 4.74% 196

and TS between 0.05 and 0.39% while there is no or only negative correlation between the two parameters. Mo remains very low and varies between 3.41 and 14.53 ppm while V concentrations change within a large range of between 407.9 and 1574.74 ppm. There is no correlation between Mo and TOC, but instead for Mo and TS over that short distance, indicating incorporation of Mo into sulphurized organic matter (Tribovillard et al., 2004) and possibly also Mo fixation by adsorption onto pyrite surface (Huerta-Diaz and Morse, 1992; Helz et al., 1996; Bostick et al., 2002). V, on the other hand, follows the TOC profile more closely. Mo/TOC and V/TOC vary according to the trace metal pattern. In both intervals, Fe concentrations remain within a similar range of between 0.8 and 2.7% for the one within the lower Shiyantou and between 1.4 and 3.1% for the interval in the upper Shiyantou Fm. Mn and Ba concentrations are also varying within a similar range in both intervals, with Mn averaging 76.6 ppm within the lower interval and 149.6 ppm in the upper interval. Ba contents average 976.8 and 1171.7 ppm respectively. Iron speciation data confirm an anoxic-ferruginous depositional environment with FeHR/FeT fluctuating above 0.38 and FePy/FeHR being close to zero. As already mentioned, the high resolution data from the 2nd black shale (XTY17-20) shows little variation with TOC contents averaging 2% while TS varies between 0.02 and 0.79 % at the top. Mo varies between 5.14 and 13.24 ppm and V remains closely around 190 ppm, Mo/TOC and V/TOC vary accordingly. Th/U shows an average of 2.35 but iron speciation suggests deposition under an anoxic-ferruginous water column while FePy/FeHR remains close to zero.

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Figure 5.25: The geochemical profiles of higher resolution intervals taken within the lower and upper Shiyantou black shale successions.

5.3.4. Other Early Cambrian sections on the southwestern platform (Yunnan Province)

5.3.4.1. The Deze Section (Zhongyicun Fm., Dahai Mb.)

The predominantly carbonatic lithology of the Dahai Mb. is TOC and TS poor throughout and accordingly depleted in redox-sensitive trace-metals as well as in Fe and Mn (see Fig. 5.26). Only Ba is significantly enriched with concentrations between 701.7 and 2163.2 ppm. Cu tracks TOC contents very well while Ni is only weakly correlated. A moderate correlation is seen between V and U and TOC but not between Mo and TOC. No covariation is found between TS, which is almost fully bound as pyrite S, and TOC contents. Th/U ratios are variable around 2 and V/(V+Ni) between 0.7 and 0.91. Iron speciation suggests anoxic-ferruginous conditions throughout the section with FeHR/FeT values close to 1 and FePy/FeHR ratios below 0.5. A few

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sulphide isotopic compositions have been measured and indicate pyrite enriched in

34

S with

δ34S values between 9.5 and 21.6‰ (VCDT).

Figure 5.26: The geochemical profile through the lower part of the Dahai Mb. (Zhujiaqing Fm.) which is mainly composed of carbonates and some chert beds.

5.3.4.2. The Meishucun Section (lower Shiyantou Fm.)

The stratigraphically poorly correlated samples from the lower Shiyantou Fm. at Meishucun show moderate TOC contents, which correlate negatively with comparatively high TS concentrations reaching values of 2.36% (see Fig. 5.27). Mo varies between 3.7 and 9.44 ppm and correlates with V concentrations varying between 150.5 and 459.1 ppm. Only two samples have been analysed for U which remains around 10 ppm with Th/U ratios of 0.51 and 0.94. Mo/TOC ratios average 4.5 and V/TOC ratios fluctuate around 230, both being in the same range as the ratios found throughout Xiaotan. Fe concentrations tend to increase through the section from 2.2% to over 3%. Mn and Ba concentrations do not demonstrate enrichment but indicate a mirror pattern where the highest Mn content of 811.9 ppm coincides with the lowest Ba concentration of 270.8 ppm at the lowermost part of the section. In addition, no significant enrichment is seen for Ni and Cu with concentrations around average shale (or UCC) values but both elements correlate moderately well with TOC contents. Around the Shiyantou/Yuanshan boundary, overall low concentrations of trace-metals coincide with high TS concentrations of 199

up to 3.4% and very high P content of up to 10.8%. V/(V+Ni) values remain within a narrow range of between 0.71 and 0.88. Iron speciation analysis indicates anoxic-ferruginous conditions but rather high FePy/FeHR ratios of up to 0.72 indicate intermittently euxinic conditions. Sulphide isotope analysis indicates variable δ34SPyrite values between -14.4 and 2.2‰ (VCDT).

Figure 5.27: A geochemical profile through an interval within the lower part of the Shiyantou black shale at Meishucun. Note that the Shiyantou/Yuanshan boundary is at an undefined stratigraphic height.

5.3.5. Discussion: Biogeochemical cycling during the Early Cambrian on the southwestern Yangtze Platform

The present study demonstrates that the three black shale successions at Xiaotan exhibit rather different geochemical characteristics (see Fig. 5.28). Plotting TS vs. TOC (see Fig. 5.24a) shows that from the 1st black shale upwards, S/C ratios tend to increase without correlating, even while average TOC contents slightly decrease and average TS concentrations increase. From the 1st to the 3rd black shale succession we find clearly increasing average Fe, Mn and U concentrations and slightly increasing Ba and S concentrations. While Mo values are highest within the 3rd black shale succession, V contents are highest in the 1 st black shale such as are TOC contents. Mo and V vs. TOC (see Fig. 5.24b) show moderate correlation in the 1 st black shale and good correlation in the 3rd black shale succession. Other redox-sensitive trace200

metals such as Ni and Cu are depleted and exhibit no clear trend. While iron speciation data analysis suggests anoxic-ferruginous conditions throughout the deposition of the sampled section, we find FeHR/FeT ratios consistently below 0.38 above the last black shale in the Yuanshan Fm. The Early Cambrian on the Yangtze Platform shows, at least in the South, significant differences in sediment thicknesses, which have also been demonstrated for the Ediacaran Doushantuo (Vernhet, 2007) and late Ediacaran Dengying formations (Steiner et al., 2007). And the Xiaotan section represents one of the most expanded and probably most complete section covering the Precambrian-Cambrian transition in South China or even worldwide. Increasing S/C ratios towards the Yuanshan Formation could imply a transition to more open marine conditions with increased circulation leading to increased concentrations of sulphate in the seawater intensifying sulphate-reduction and pyrite precipitation. Other studies have demonstrated a variable but generally low sulphate reservoir in the ocean across the Precambrian-Cambrian ocean which increased throughout the Phanerozoic (e.g. Canfield, 2004; Hurtgen et al., 2009). Recently, Canfield and Farquhar (2009) hypothesized that sulphate levels in the ocean significantly increased after the onset of bioturbation around 555 Ma (Martin et al., 2000). Alternatively, the upwelling of sulphide-rich water masses from deeper levels of the Yangtze Platform, which has been shown to have been at least intermittently euxinic in transitional settings on the platform margin, such as in Zhongnan and Meishucun (e.g. this study; Canfield et al., 2008), might explain the apparent decoupling of TOC and sulphur contents in the upper black shales. However, such a putative H2S release to surface waters has been hypothesized by Wille et al. (2008) to explain transient Mo isotope signals in another Early Cambrian succession close to Zhongnan on the Yangtze Platform margin. Furthermore, total sulphur is increasingly equivalent to pyrite sulphur towards the top of the Yuanshan Formation (see Fig. 5.29) while an important fraction of TS in the lower black shales is mostly non-pyritic and probably represents sulphur bound to organic matter and other S phases. This might indicate that sulphate-reducing conditions were not met during the deposition of the earlier black shale successions, i.e. a reducing setting merely reaching denitrifying conditions, which is also supported by very high V enrichment and virtually no Mo enrichment in the 1 st black shale.

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However, such an explanation fails to explain why Mo, V and U are all not significantly enriched in the upper successions towards the Shiyantou/Yuanshan boundary, which might be due to anoxic draw down of the trace-metal reservoir which is indicated within the interval sampled at Meishucun, where minimum Mo and V concentrations are found within the euxinic intervals.

Figure 5.28: The compiled data for the Xiaotan section and the more condensed Dapotuo section for comparison. Note the similar patterns and concentrations except for TS which reaches higher values in the Yuanshan Fm. of the Dapotuo section. The shaded background on the stratigraphic column of the Xiaotan section refers to iron speciation results whereby the shading out in the upper part of the Yuanshan Fm. refers to FeHR/FeT ratios below the threshold firmly confirming anoxia of 0.38.

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Figure 5.29: There is significant non-pyrite sulphur in the lower two black shale members and good correlation and almost exclusively pyrite sulphur in the 3rd black shale succession in the Yuanshan Fm. The two data points below the 1:1 line represent measurements

with

very

low

sulphur

content prone to inaccuracies.

The transition to open marine conditions and increasing trace-metal availability is supported by overall increasing Mo/TOC ratios. But we must keep in mind that strictly speaking, the Mo/TOC ratio as proxy for Mo availability only applies in sediments deposited under euxinic conditions, where quantitative removal can be expected. Nevertheless, similar Mo/TOC ratios within the intermittently euxinic Shiyantou Fm. at Meishucun suggest that Mo might have been a limiting nutrient during the Early Cambrian on the southwestern platform. The perfect correlation between Mo and TOC in the black shale at the base of the Yuanshan Formation suggests a water column with more abundant Mo which leads to Mo removal at the same rate as organic matter burial or the transition from a weakly reducing depositional setting to sulphate-reducing conditions, evidenced by the increasing ratio of pyrite sulphur to total sulphur. Above the last black shale succession, Iron speciation and Th/U ratios suggest that bottom waters might have developed towards less reducing conditions, at Xiaotan but also at Dapotuo (see appendix for the detailed dataset). Iron speciation data suggests intermittent euxinia during the deposition of the lower Shiyantou Fm. at Meishucun with very high sulphide contents. This either indicates highly variable redox conditions on the Yangtze Platform or, because the Meishucun samples have been collected in an actively exploited mine, that Xiaotan is weathered to some extent. On the other hand, the nearby Dapotuo section also exhibits high TS contents and suggests higher 203

sulphur/pyrite contents further south on the Platform. The use of V/TOC ratios to infer fluctuations of the V reservoir cannot necessarily be applied accordingly and we suggest that redox conditions are primarily controlling V accumulation in the sediment although it can be argued that the V reservoir is significantly affected by the early sequestration from denitrifying conditions already, which would led to its depletion after the deposition of the 1st black shale. The relative inconsistency of the different paleoredox proxies including V/(V+Ni), Th/U and iron speciation together with overall low trace-metal concentrations approaching average shale (except for V in the 1st black shale) are striking. V/(V+Ni) seems particularly inappropriate when used to infer sulphidic conditions. Several reasons have to be considered: (1) the probably restricted access to the open ocean of wide regions on the Yangtze Platform leading to suppressed trace-metal enrichment, (2) an overall transitional character of trace-metal geochemistry during the late Neoproterozoic and early Cambrian and (3) a likely sulphate-poor basin inhibiting sulphate-reduction and subsequent development of euxinic conditions. Consequently, the use of paleoredox proxies involving redox-sensitive trace-metals might be preferably restricted to Phanerozoic, post-Cambrian studies only. A conspicuous Ni enrichment horizon occurs in the upper Shiyantou Fm. which despite the relatively coarsely resolved sampling shows a gradual increase within about 2m. We argue here that this Ni peak in Xiaotan might be correlated with the intensely studied Ni-Mo sulphide layer found along the platform margin. The origin of this unusual Ni and Mo enrichment found along the platform margin is still not agreed upon. Whereas some suggest a hydrothermal origin (e.g. SEDEX deposits: Lott et al., 1999; Steiner et al., 2001) others advocate a seawater origin (Mao et al., 2002; Lehmann et al., 2007) or multiple sources for the observed metal enrichment (Pašava et al., 2008). Age constraints are often imprecise: there exists a Pb-Pb age of 521±54 Ma for the metalliferous horizon itself and a Pb-Pb age of 531±24 Ma for the underlying black shales (Jiang et al., 2006). A more recent, more precise U-Pb SHRIMP age of 532.3±0.7 Ma from a volcanic ash bed between the phosphorites and the Ni-Mo layer (Jiang et al., 2009) sets a narrower timeframe and emphasizes the extremely condensed character of the early Cambrian sediments within the transitional belt but would not conflict with U-Pb ages set by Compston et al. (2008) for the middle Zhongyicun Mb. of 539.4±2.9 Ma and for the basal

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Shiyantou Fm. of 526.5±1.1 Ma. There is a distinct possibility of two separate metal enrichments: an earlier one due to SEDEX-type mineralisation including Ni as a typical element and a second one due to redox processes leading to high TOC and Mo accumulation (see Fig. 5.30), which only appear to be coeval within the strongly condensed sedimentary successions at the platform margin. In addition, the high sulphide contents with concomitant low TOC levels and the inferred euxinic conditions at Zhongnan might well correspond to the elevated pyrite levels above the last black shale at the base of the Yuanshan Fm. at Xiaotan, where the strong bimodal covariation pattern of TOC and TS are also observed. Moreover, the earlier V enrichment seen in the bottom Shiyantou Fm. at Xiaotan, below the Ni-Mo horizon at Zhongnan and other Early Cambrian section, which can attain a few percent as well (e.g. Wallis, 2006; Guo et al., 2007), additionally supports a platform-wide correlation based on redoxsensitive trace-metals. The succession of Ni-Mo enrichment, pyrite horizons and high TOC contents has not been reported elsewhere and is probably due to diagenetic redistribution or, because of a certain conglomeratic character of the interval (see also Steiner et al., 2001), the sampling could have lead to a slightly altered rendition of the true geochemical situation to some extent.

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Figure 5.30: A possible correlation can be established between the highly metalliferous black shales of the lower Niutitang Fm. in the transitional belt and the distinct Ni peak found within the upper Shiyantou Fm. Precise age constraints are sparse (*Compston et al., 2008; **Jiang et al., 2009: between the phosphorite and the ore layer) but do not contradict the possibility of such a geographically extensive geochemical Ni marker horizon.

The present study shows that the geochemical record can be explained by invoking long and short-term water depth fluctuations indicating overall rising eustatic sea level leading to increased Mo/TOC ratios and subsequently to an influx of H2S from the adjacent deeper regions 206

and basin of the Yangtze Platform (see Fig. 5.31). The latter is suggested by dominantly low Mo enrichement at Xiaotan, significant occurrence of non-pyrite sulphur and bimodal TOC vs. TS covariation patterns which indicate low sulphate-reduction rates in the platform interior but upwelling of sulphide rich waters from the basin. Furthermore, the extensive and relatively undisturbed sedimentary successions at Xiaotan in comparison to the stratigraphy in the South of Yunnan Province suggest a deeper region on the Yangtze Platform around today’s Xiaotan section. Furthermore, it is indicated that a peak of very high Nickel concentrations within the upper Shiyantou Fm. followed by elevated Mo enrichment several meters above can be correlated with the conspicuous Ni-Mo-sulphide ore horizon found along the platform margin where the stratigraphy is strongly condensed (see Fig. 5.30). This would successfully help to solve the mystery of coupled extreme Ni and Mo enrichment by attributing the Ni-sulphide ore to a sedimentary-exhalative process and the subsequent Mo enrichment to sequestration due to increased Mo reservoir and an anoxic water column. However, the depth of Xiaotan could not have sustained the benthic life found at the well preserved fossil deposits at Chengjiang, where bioturbation has been documented and indicates at least intermittently oxic bottom waters (Conway Morris, 1989; Dornbos et al., 2005) although the typical Chengjiang Biota most likely represents an assemblage transported away from a nearby, more life-prone environment (Zhang and Hou, 2007; Gaines and Droser, 2010). Increased access to the open ocean during the Early Cambrian could on one hand have lead to the upwelling of nutrients onto the Yangtze Platform together with sulphide-rich water which would have immediately precipitated as pyrite due to Fe(II)-rich waters without leading to euxinic bottom waters in the Xiaotan region. The higher sulphur contents and the putative development of euxinic environments further south of the Yangtze Platform could suggest proximity to the open sea, and probably their position and depth with respect to upwelling nutrients. As euxinia has been demonstrated for Early Cambrian successions deposited in the basin (previous chapters; Canfield et al., 2008), a triangular model such as Li et al. (2010) proposed for the Late Ediacaran cannot be supported nor refuted by the situation found on the southwestern platform. On the other hand, the addition of large shallow-water continental margins would have made the colonisation by recently evolved metazoans possible while still maintaining an environment which would

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favour fossil preservation under anoxic conditions as well as episodic extinction events. Widespread anoxic and even euxinic environments on the south-western Yangtze Platform, possibly represented in Meishucun, could provide necessary preservation traps which gave us the perfectly preserved Chengjiang Biota. While it is unclear how and whether the upwelling of sulphide-rich waters over a probably extended amount of time impacted on the biosphere it is nevertheless interesting to see that the deposition and preservation of the exceptional Chengjiang Biota on the Yangtze Platform closely followed this interval. Future studies will hopefully reveal whether the biological innovations witnessed in the fossil record at Chengjiang where delayed, preserved or even made possible through a fragile and diverse environment creating numerous niches of differing biogeochemical parameters and thus acting as an evolutionary laboratory.

Figure 5.31: A possible model of the situation on the southwestern Yangtze platform with rising sea levels first leading to an increase in the Mo budget and subsequently to the upwelling of H 2S into the inner platform. The position of the sections analyzed refers to their distance from the open ocean.

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5.4.

Biogeochemical cycling across the Precambrian – Cambrian transition on the Yangtze Platform: summary and global perspective The application of redox-sensitive trace-metals (Mo, V and U) have proven to be a

valuable tool to infer paleoredox conditions in Phanerozoic marine sediments (see reviews by Tribovillard et al., 2006; Meyer and Kump, 2008; Lyons et al., 2009) when cautiously applied in combination with other, independent redox indicators such as stable isotopes and iron speciation and a good understanding of the architecture of the depositional environment with regard to physical barriers affecting trace-metal availability in the water column (e.g. Algeo and Lyons, 2006). This approach is more complicated for Precambrian sediments when low oxygen levels limited oxidative weathering, hence causing a limited renewal of the oceanic trace-metal reservoir from the continents, and widespread anoxic or even euxinic deep waters might have efficiently draw down the seawater inventory of redox-sensitive trace-metals (e.g. Scott et al., 2008). The rise in atmospheric oxygen levels and the ventilation of the deep sea during the Neoproterozoic Oxygenation Event mark, amongst other major revolutions on the Earth surface, the transition from marine sediments predominantly poor in redox-sensitive elements to highly enriched black shales (see chapter 2). Regardless of the mechanism, it can be assumed that a significant increase in dissolved trace-metals concentrations in the ocean took place whereas the timing remains under debate and most likely did not follow a globally uniform pace, which can be illustrated by available data on Mo and V concentrations in black shales between 700 and 400 Ma (see Fig. 6.1 and 6.2). Although there is a scarcity of black shale data coming from localities outside the Yangtze Platform, we observe some enrichment within the interglacial Datangpo Fm. (~663 Ma) and then a gradual increase from lower Mo concentrations to a peak at the base of the Cambrian followed by a gradual decrease throughout the Paleozoic (see Fig. 6.1a). In addition to high Mo enrichment presented in this study, very high Mo concentrations are found within a black shale succession deposited around the Precambrian – Cambrian boundary within the Ara Group, Oman (Schröder and Grotzinger, 2007; Wille et al., 2008) while only minimal enrichment has been reported from basal Cambrian black shales from the Tarim Basin, Northwest China (Yu et al., 2009). However, variations of Mo/TOC ratios across the same 209

interval are clearly dominated by values reported from the Yangtze Platform and suggest an extraordinary and particularly efficient removal of Mo from the water column within the depositional environment on the Yangtze Platform. The temporal trends in V accumulation in black shales (see Fig. 6.2a) follow a similar pattern, describing a sharp rise from the late Ediacaran and a peak in the earliest Cambrian. Although concentrations decrease for the rest of the Paleozoic, values above 2000 ppm remain common. Apart from black shales from the Precambrian – Cambrian boundary on the Yangtze Platform, extremely high V concentrations of up to 1.2% have been observed within the Tarim Basin (Yu et al., 2009) while they remain moderate within the black shale succession in the Ara Group, Oman, according to the study by Schröder and Grotzinger (2007). The anomalously high Mo concentrations within the Ni-Mo sulphide ore layer in the lower Niutitang Fm. have to be critically appreciated since it represents a highly condensed section but very high Mo concentrations and Mo/TOC ratios occur already within the Miaohe Mb. of the Doushantuo Fm. at Jiulongwan ca. 551Ma, in the Jiumenchong Fm. within transitional and basin sections and within the Shuijingtuo Fm. on the northern Yangtze Platform. The same applies for V although the proportion with respect to Mo varies significantly and reflects differences in redox-sensitivity. Hence, exponentially increasing concentrations of redox-sensitive trace-metals from the Early Ediacaran towards the Early Cambrian can be firmly confirmed for the Yangtze Platform and preliminary data from the Tarim Basin (Yu et al., 2009) and the Ara Group in Oman (Schröder and Grotzinger, 2007) suggest that this increase was not limited to the depositional environments on Yangtze Platform.

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Figure 6.1: A) Mo concentrations in black shales from the 700 to 400 Ma (see also Fig. 2.2). Black dots represent data acquired from the Yangtze Platform, orange diamonds are specifically from the Niutitang Fm., and red dots show measurements reported from elsewhere. Anomalously high Mo concentrations from the Ni-Mo sulphide ore layer at the base of the Niutitang Fm. in the range of a few percent have been omitted here. B) Temporal trends in Mo/TOC ratios are from the same dataset and generated with TOC contents above 1% where available. While Mo concentrations increase and decrease gradually around a peak at the base of the Cambrian, Mo/TOC ratios are high in black shales deposited during the Precambrian – Cambrian transition on the Yangtze Platform but remain low in available analysed sediments deposited elsewhere.

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Figure 6.2: A) Temporal trends in V concentrations in black shales on the Yangtze Platform (black), specifically within the Niutitang Fm. (orange diamonds) and within black shales from other parts of the world (red dots). Note the exponential increase from the Early Ediacaran towards the Early Cambrian before V contents decrease again while maxima remain above 2000 ppm for the Paleozoic. B) V/TOC ratios, applying a TOC threshold of 1%, between 700 and 400 Ma demonstrate very high values during the Precambrian – Cambrian transition with a maximum within the Miaohe Mb. of the Doushantuo Fm. ca. 551 Ma and ratios below 500 for most of the Ediacaran and the Paleozoic.

Mo and V concentrations in black shales do not only vary globally but especially within the Yangtze Platform which has been demonstrated to depend on the access to the open ocean 212

for a given depositional environment. Figure 6.3 and 6.4 show maximum Mo and V concentrations by section locality whereby the vast datasets from Wallis (2006) and Guo et al. (2007) have been incorporated. Although there is a lack of sections exposing sedimentary successions across the Precambrian – Cambrian boundary and a quantitatively more important dataset covering the Early Cambrian, both trace-metals increase considerably from the Ediacaran to the Cambrian. High V concentrations are already found within some Ediacaran succession on the Northern platform while a more widespread distribution of V enriched black shales is seen during the Cambrian. The increase in maximum Mo concentrations is more pronounced and a greater disparity is observed regarding the depositional environment so that we find the highest enrichment within transitional and slope sections, moderate enrichment on the platform and particularly low concentrations on the Southwest platform. Although the patterns of element/Sc ratios rarely differed much from element concentrations alone throughout individual sections, normalizing trace-metal concentrations to a common denominator can enhance the comparability between the different depositional settings as shown in figure 6.5.

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Figure 6.3: Maximum Mo concentrations found within Late Ediacaran and Early Cambrian black shale successions on the Yangtze Platform. Besides the pronounced increase of Mo concentrations across the Precambrian – Cambrian boundary, significant differences are found amongst the investigated section (this study, Wallis, 2006; Guo et al., 2007), particularly during the Early Cambrian.

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Figure 6.4: Maximum V concentrations in Late Ediacaran and Early Cambrian black shales on the Yangtze Platform including data from Wallis (2006) and Guo et al. (2007). Note that very high concentrations occur already during the Ediacaran but are more widespread after the Precambrian – Cambrian boundary.

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the south western Yangtze Platform (Yunnan Province).

(Jiulongwan etc.) while Early Cambrian trace-metal enrichments are more widespread except on

Very high ratios are attained in Late Ediacaran successions around the Three Gorges Area

contents in one or more trace-metals, have a width of Mo/Sc = 300, V/Sc = 1000 and U/Sc = 150.

Mo/Sc = 30, V/Sc = 400 and U/Sc = 10 and yellow shaded columns, indicating particularly high

Yangtze Platform (this study; Wallis, 2006; Guo et al., 2007). Grey shaded columns have a width of

organic rich marine sediments deposited during the Precambrian – Cambrian transition on the

Figure 6.5: Summary of normalized redox-sensitive trace-metals (Mo/Sc, V/Sc and U/Sc) from

According to Algeo and Lyons (2006), there is a nearly linear relationship between Mo concentrations in anoxic sediments and dissolved Mo concentrations in the overlying water column based on the degree of restriction of the subchemoclinal water mass affecting deepwater renewal. Based on these findings, it can be attempted to quantify temporal changes of Mo concentrations in seawater which prevailed in different depositional environments on the Yangtze Platform (see Fig. 6.7). However, while the difference in dissolved Mo is minimal between the modern Cariaco Basin and Saanich Inlet, Mo contents within the anoxic sediments of Saanich Inlet are about double the ones within the Cariaco Basin. Hence, it can be expected that Mo/TOC ratios exceeding 50 will even more diverge from a linear relationship. Nevertheless, according to the discussion in the previous chapter, physical barriers causing Mo limitation can be assumed for the intra-shelf basins and/or shelf lagoons during the deposition of the Late Ediacaran Miaohe Mb. at Maoshi and Jijiawan whereas oceanic Mo concentrations probably within today’s magnitude lead to the enrichment and Mo/TOC ratios of over 180 seen in the Miaohe Mb. at Jiulongwan, which suggests an open connection to the global ocean and regular seawater renewal rates. Regarding Mb. II of the Doushantuo Fm. the situation is more complex; some advocate a restricted and even lacustrine environment (Bristow and Kennedy, 2008) and others demonstrated higher Mo/TOC ratios of up to 10 within the basal Doushantuo Fm. at Zhongling (ca. 100km south of Jiulongwan: Li et al., 2010), while Jiang et al. (2011) showed that a rimmed platform developed soon after the deposition of the cap carbonates (Doushantuo Mb. I), suggesting that paleobathymetry was already a parameter limiting Mo availability. Hence, it remains difficult to constrain the increase in the seawater inventory of redox-sensitive trace-metals in time, and it can merely be confirmed that it occurred prior to the deposition of the Miaohe Mb. ca. 551 Ma. Mo/TOC ratios within the intermittently euxinic Early Cambrian successions at Meishucun, Longbizui, Zhongnan and Jijiawan show average Mo/TOC ratios between 4 and 14 but maxima above 30 for some horizons at Zhongnan and Jijiawan, similar to modern anoxic environments. Although a lack of precise paleogeographical studies of the Early Cambrian on the Yangtze Platform must be acknowledged, there is no indication for physical limitation of Mo availability going from the Jijiawan section in the North down to the Meishucun in the

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Southwest and including the slope and basinal sections at Zhongnan and Longbizui stretching over more than 1000km and a redox-controlled widespread draw down of the seawater tracemetal inventory could account for predominatly low Mo/TOC ratios (see Fig. 6.6). Although an overall increase in V/TOC across the Precambrian – Cambrian boundary can be observed (see Fig. 6.2b), the variation patterns amongst the investigated sections are very different from Mo/TOC ratios. V/TOC ratios remain within a narrow range throughout the Jijiawan section, from the lower part of the Doushantuo up to the Shuijingtuo Fm. There is significant variation within the Longbizui section but V/TOC averages within the Ediacaran Liuchapo and the Cambrian Jiumenchong remain virtually the same as opposed to the Hunaglian section where low V/TOC ratios within the Liuchapo do not overlap with very high ratios of up to 1050*10-4 found within the Jiumenchong Fm. Furthermore, as already mentioned in chapter 5.3.3., V/TOC ratios are not following any clear trend at Xiaotan as opposed to the gradual increase of average Mo/TOC ratios but both ratios are similar between the Meishucun and Xiaotan sections, implying relatively uniform trace-metal concentrations on the south western Yangtze Platform.

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Figure 6.6: Range of Mo/TOC ratios from sections on the Yangtze Platform compared to modern anoxic environments (modified after Algeo and Lyons, 2006). Yellow coloured circles indicate intermittently euxinic sedimentary successions. A TOC threshold of 1% has been applied for the Zhongnan section due to unreasonably high Mo/TOC in within the organic-poor Ni-Mo sulphide horizon.

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Figure 6.7: Range of V/TOC ratios divided by section and geological formations. Intermittently euxinic formations are indicated by yellow circles.

A more detailed illustration of Mo/TOC ratios and redox conditions based on iron speciation analysis is shown in figure 6.8. Although pronounced euxinic conditions, such as within the Miaohe Mb. and the Early Cambrian Jiumenchong Fm., suggest enhanced Mo removal from the water column, a systematic relationship between euxinia and Mo scavenging is not supported (e.g. Algeo and Lyons, 2006). On the other hand, it can be observed that Mo/TOC ratios above 15*10-4 occur exclusively within sedimentary successions where intermittent euxinia is indicated although not necessarily within the same horizon (see also Fig. 6.6). This suggests that the increase of molybdate and sulphate concentrations in seawater follow similar mechanisms (e.g. Algeo et al., 2007), which is also suggested by a similar patterns 220

of Mo/TOC and S/TOC ratios across the Precambrian – Cambrian transition (see Fig. 1.13). And while sulphidic environments represent conditions favourable for Mo sequestration it is primarily a question of an increasing Mo reservoir, together with increasing sulphate concentrations eventually leading to sulphidic environments, which lead to increasing Mo concentrations in black shales during the Neoproterozoic – Cambrian transition. The widespread sulphidic conditions seen during the Late Ediacaran ca. 551 Ma are accompanied by significant barite enrichment in deeper regions of the platform (e.g. Baiguoyuan) while probably

more

widespread

sulphidic

conditions

during

the

contemporaneous to extended, massive barite deposits in the basin.

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Early

Cambrian

are

Figure 6.8: Summary of iron speciation and Mo/TOC ratios. Sections have been broadly subdivided into platform and basin whereby the transitional Zhongnan section has been included amongst the slope and/or basinal sections at Longbizui and Huanglian. Note that stratigraphic correlations across the platform are easily achieved for the Doushantuo Fm. and between the Early Cambrian formations in Yunnan and Hubei (Three Gorges Area) whereas the Niutitang and Jiumenchong Fm. are likely to have been deposited with significantly lower sedimentation rates and the upper Liuchapo Fm. possibly continued into the Cambrian (e.g. Wang et al., 1998).

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6.

Conclusions

6.1.

The biogeochemical cycling of redox-sensitive trace-metals during the Precambrian – Cambrian transition on the Yangtze Platform During the Precambrian –Cambrian transition we observe an exponential increase in

redox-sensitive trace-metal concentrations in black shales by at least one magnitude, notably Mo, V and U, most likely caused by the Neoproterozoic Oxygenation Event which is likely to have occurred after the break-up up of the supercontinent Rodinia and the onset of major glaciations but before the late Ediacaran, where we find the oldest evidence for extreme Mo, V and U enrichment. The underlying cause for the enrichment is likely to be enhanced oxidative weathering and oxygenation of the sea floor, possibly by intensified reworking, which lead to an increasing Mo, V and U seawater inventory alongside with increasing sulphate concentrations in the ocean. There is no convincing evidence that a global retreat of anoxic-sulphidic conditions in the deep ocean lead to overall higher trace-metal concentrations in the ocean and, although available data based on iron speciation is sparse for the Early Neoproterozoic, it is likely that euxinic conditions were rare in a sulphate-poor, predominantly ferruginous Neoproterozoic ocean. However, it has been demonstrated that redox-sensitive trace-metals can reflect paleoceanographic evolution form a regional point of view. During the sedimentation of the Ediacaran Doushantuo Fm. on the Yangtze Platform, the development of a rimmed shelf soon after the deposition of the cap carbonates lead to trace-metal limitation within the shelf lagoon and numerous intra-shelf basins such as reflected by Mo/TOC ratios. Subsequent flooding of the inner platform and enhanced access to the open ocean increased trace-metal availability such as at Jiulongwan during the transition from Member II, with low trace-metal concentrations, to the Miaohe Member (Doushantuo Mb. IV), where the highest Precambrian Mo concentrations on record occur. Depositional basins further inside the platform, such as Jijiawan, do not exhibit elevated trace-metal concentrations during the Ediacaran and represent restricted depositional environments. During the Early Cambrian, the geochemical profiles at 223

Jiulongwan and Jijiawan exhibit a similar pattern indicating that open oceanic circulation extended further onto the platform. Sulphide isotope analysis supports this scenario and suggests that seawater sulphate concentrations increased alongside molybdate and other oxidized trace-metals while at the same time triggered euxinic conditions and Mo sequestration. While euxinic conditions were widespread during the Early Cambrian, from the shelf to deeper parts of the Yangtze Platform, the southwestern inner platform remained anoxicferruginous except along the platform margin and the transitional zone, the latter being represented by the condensed Zhongnan section. The ubiquitous black shale associated Ni-Mo sulphide ore layer at Zhongnan can be correlated with the sedimentary succession at Xiaotan, more than 300km westwards on the shelf, where a thin Ni enriched horizon and a Mo enriched black shale succession a few meters further up have been found. This suggests that two separate mechanisms lead to the Ni-Mo ore horizon, which occurs along the transitional zone, notably a SEDEX-type mineralization resulting in high Ni concentrations and other associated metals followed by a redox driven Mo enrichment. This constrains the age of the Ni-Mo sulphide ore horizon at around 521 Ma and suggests that the biological innovations recorded in the fossil Lagerstätte at Chengjiang, also on the southwestern platform, might have emerged shortly after the retreat of widespread sulphidic conditions on the Yangtze Platform. Moreover, the pronounced euxinic conditions which seem to have prevailed during the Late Ediacaran and the Early Cambrian could be linked to the demise of the Ediacara Biota and the subsequent Cambrian Explosion.

6.2.

A multi-proxy approach to investigate ancient paleoredox conditions

The combined analysis of Mo, V and U concentrations in black shales demonstrated that it is possible to confidently differentiate redox conditions which prevailed during the deposition of the analysed sedimentary successions. At the Xiaotan section for example, elevated V and low Mo concentrations within the black shale succession in the lowermost Shiyantou Fm. indicate oxygen depletion without reaching sulphate-reducing conditions. This changed further up during the deposition of the lowermost Yuanshan Fm. where Mo enrichment takes place and 224

tracks organic carbon. On the other hand, it has been shown that higher U concentrations with respect to Mo concentrations, i.e. higher U/Mo ratios, point to strongly reducing conditions without the release of significant amount of free H2S, such as during the deposition of the black shale of the lower Shuijingtuo Fm. in the Early Cambrian. It also became apparent that sulphidic conditions, indicated by iron speciation analysis, do not necessarily lead to coeval high Mo enrichment or elevated Mo/TOC ratios. However, sedimentary successions where intermittent euxinia occurs are the only ones where Mo/TOC ratios above 15*10-4 were observed at some point in the stratigraphy. Furthermore, the high resolution geochemical analysis of parts of the uppermost black shale of the Doushantuo Fm. (Miaohe Mb.) exhibits some cyclicity between Mo and Ba enrichment which could indicate dynamic changes in seawater chemistry involving episodic euxinia but it is startling that high Mo concentrations occur within the same zone as elevated Mn concentrations which might indicate Mo delivery to the seafloor by adsorption onto Mn-oxyhydroxides which is not considered to be an efficient enrichment mechanism. Barite within the sediment could have been reduced and lead to vertically very restricted thiomolybdate precipitation fronts.

6.3.

Future challenges The biogeochemical cycling during the Precambrian – Cambrian transition on the

Yangtze Platform is clearly intriguing and demonstrates a highly dynamic interval in Earth’s history. Further studies outside the Yangtze Platform are needed to constrain the outlined geochemical changes from a global perspective and show whether the Yangtze Platform really experienced unique biogeochemical conditions or truly represents a unique sedimentary archive of the Precambrian – Cambrian transition. Moreover, there is a striking scarcity of geochemical investigations on sedimentary sequences prior to the Neoproterozoic glaciations predominantly due to preservational hiatuses created by major tectonic upheavals that occurred during the break-up of Rodinia. Concentrating on potentially available Early Neoproterozoic sedimentary successions would considerably improve our understanding of the Earth’s surface chemistry and metazoan evolution. 225

Furthermore, the redox chemistry of molybdenum has to be better understood in particular with regard to pathways and mechanisms leading to molybdenum sequestration from the water column and fixation in marine sediments. Only few studies on Mo limitation as a trace nutrient have been conducted and further investigation should shed light on the connection between the biological innovations occurring during the Precambrian – Cambrian transition and the increased availability of redox-sensitive trace-metals in seawater. And, last but not least, improved understanding of the consequences following the emergence of bioturbation is paramount in understanding the Neoproterozoic Oxygenation Event and in concert with improved age constraints, notably of the Early Cambrian on the Yangtze Platform, there is good potential to better understand the co-evolution of marine chemistry and the advent of architecturally more complex metazoans.

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Formal Acknowledgements The present study has been made possible by the German Research Foundation (DFG) and the National Science Foundation of China (NSFC) through the Sino-German Research Project FOR 736. The geochemical analysis was carried out at the Royal Holloway, University of London (XRF and LA-ICP-MS), at the State Key Laboratory for Mineral Deposit Research, Nanjing University (ICP-MS), at the Civil Engineering and Geosciences Department, Newcastle University (iron speciation), at the Wolfson Laboratory, Birkbeck, University of London (C/S analysis), and at the Institute of Geology and Paleontology, University of Münster (sulphide isotope analysis).

Personal Acknowledgements I would like to express my deep gratitude to my supervisor Graham Shields-Zhou who accepted me as his student, let me work with a great deal of independence and took me out for a beer or two once in a while. His knowledge, enthusiasm and in particular his great personality made the past three years a pleasurable time. Great thanks also to Ying Shields-Zhou who was often a companion in the best of times and created space for good discussions and excellent fun. I will never forget the great dinners and the unforgettable Chinese New Years I had the opportunity to experience at their house. At this point, I would also like to express my appreciation for my colleague and friend Lorenzo with whom our road trips in China and elsewhere around the globe gained an extra value. Furthermore, I would like to thank Hongfei Ling, a superb person and scientist, for accompanying us in the Chinese countryside and for his overall helpfulness, from an academic and personal point of view. Great thanks are also due to my colleague Li Da, with whom most of my time in London would have been much sadder, and my colleague Chen Xi with his great humour and wit. Great thanks to Christina Manning for her substantial help, advice and her very pleasant cheerfulness while I was doing less exciting sample preparations. Further thanks to Matthew Thirlwall and Wolfgang Müller for their inspiring attitude and great help. All three are at the

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Royal Holloway, University of London. I’m also indebted to Tony Osborne from the Wolfson Laboratory, and Simon Poulton, Newcastle University, for letting me run riot in his lab. Many, many thanks to my dear family for their great support and for their numerous visits while I was in London. And, last but not least, many thanks to my beloved Yilei for being there in great but also difficult times.

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Correlation coefficients (R2) between redox-sensitive elements in some Late Ediacaran and Early Cambrian black shale successions R2 values in bold represent moderate to good correlation and values in red emphasize excellent correlation. Negative correlation is indicated by the minus sign. Late Ediacaran black shale successions Jiulongwan section (Miaohe Member: JLW41-60) R2, n = 19, (correlation coefficients of Sc excl. JLW50!) Mo V U Ni Cu Fe Mn Ba TOC TS Sc Element Average Molar ratio

1 0.53 0.43 0.22 0.01 0.06 0.01 0.03 -0.09 0.01 0.26 Mo ppm 115.0

V ppm 1221.5

U ppm 15.8

1.2

24.0

0.1

1 0.37 0.37 0.16 0.17 0.08 0 -0.2 0.04 0.54

1 0.28 0.03 0.13 0 0.15 -0.04 0.14 0.51

1 0.33 0.08 0.24 0.29 -0.15 0.1 0.53 Ni ppm 104.5

1 0.24 0.17 0.14 -0.18 0.23 0.31 Cu ppm 52.7

1.8

0.8

1 0 0.01 -0.42 0.91 0.36

1 0.06 0.07 0.17

1 -0.31 -0.29

1 0.4

1

Fe % 2.5

1 0.08 -0.07 0.02 0.31 Mn ppm 246.6

Ba ppm 2709.1

TOC % 5.5

TS % 2.2

Sc ppm 15.0

450.7

4.5

19.7

4613.7

691.3

3335.1

1 -0.02 0.09 0.24 0.56 0.54 Mn ppm 39.6 0.7

1 0.03 0.03 0.28 -0.01 Ba ppm 590.6 4.3

1 0.25 0.05 0.64

1 0.2 0.37

1 0.22

TOC % 2.4 2029.6

TS % 1.4 431.8

Sc ppm 10.0 2233.5

Jijiawan section (Miaohe Member: JJ5-12) R2, n = 8 Mo V U Ni Cu Fe Mn Ba TOC TS Sc Inorg. C Element Average Ratio

1 0.33 0.64 0.82 0.56 0.36 0.34 0 0.02 0.49 0.17 0.25 Mo ppm 1.7 0.0

1 0.36 0.32 0.39 0.61 0.13 0.4 0.24 0.73 0.4 0.24

1 0.53 0.29 0.39 0.56 0.06 0.01 0.41 0.65 0.19

1 0.85 0.22 0.51 -0.01 0.07 0.52 0.2 0.33

V ppm 71.2 1.4

U ppm 1.5 0.0

Ni ppm 23.0 0.4

1 0.31 0.38 -0.01 0.19 0.67 0.1 0.39 Cu ppm 14.6 0.2

266

1 0.14 0.16 0.1 0.87 0.24 0.18 Fe % 1.2 206.0

Maoshi section (Miaohe Member: MS1-12) R2, n = 12 Mo V U Ni Cu Fe Mn Ba TOC TS Sc Inorg. C Element Average Ratio

1 0.09 0.09 0.29 0.1 0.38 0.14 0.32 0.21 0.05 0.19 Mo ppm 3.17 0.03

1 -0.14 -0.08 -0.1 -0.11 0.84 0 -0.2 0.29 0.16 V ppm 92.08 1.81

1 0.8 0.89 0.63 -0.25 0.02 0.71 0.08 0.25 U ppm

Ni ppm 16.40 0.28

1 0.8 0.85 -0.13 0.12 0.85 0.05 0.4 Cu ppm 23.32 0.37

1 0.67 -0.2 0.05 0.83 0.1 0.15 Fe % 1.95 348.50

1 -0.14 0.16 0.78 0.01 0.21 Mn ppm 72.24 1.31

1 0 -0.22 0.23 0.05 Ba ppm 822.09 5.99

1 0.07 -0.07 0

1 0.03 0.17

1 0.28

TOC % 2.40 1997.65

TS % 1.44 449.62

Sc ppm 15.10 3358.85

Baiguoyuan section (Miaohe Member: Wallis, 2006) R2, n = 12 Mo V U Ni Cu Fe (Mn) Ba TOC TS Sc Inorg. C Element Average Ratio

1 0.29 0.46 0.73 0.06 0.37 -0.25 0.16 0.02 0.12 0.4 -0.1 Mo ppm 21.40 0.22

1 0.71 0.39 0.04 0.04 -0.41 0.15 -0.02 0.08 0.34 -0.08

1 0.49 0.07 0.08 -0.66 0.03 -0.01 0.04 0.58 -0.21

1 0.04 0.25 -0.34 0.23 0 0.25 0.57 -0.02

V ppm 3257.60 63.95

U ppm 16.15 0.07

Ni ppm 49.11 0.84

1 0.25 -0.09 0 -0.21 -0.13 0.08 0 Cu ppm 86.37 1.36

267

1 -0.05 0.28 -0.02 0.06 0.49 -0.03 Fe % 1.56 279.44

1 -0.1 0 0 -0.34 0.25 (Mn ppm) 130.00 2.37

1 0.02 0.63 0.17 0.03

1 0.21 -0.01

1 0.29

Ba ppm 5078.71 36.98

TOC % 3.05 2537.44

TS % 0.10 30.15

1 -0.24 Sc ppm 12.57 2796.07

Xiaotan section: 1st black shale succession R2, n = 28 Mo V U Ni Cu Fe Mn Ba TOC TS Sc Element Average Ratio

1 0.01

1 1

0.12 0.01 0.03 0 0.23 0.33 -0.04 0.17 Mo ppm 8.89 0.09

0.38 -0.01 -0.02 0.05 0.06 0.3 0.17 0 V ppm 654.89 12.86

1 0.13 0.07 0.06 0 0.55 0.02 -0.01 U ppm

Ni ppm 48.26 0.82

1 0.35 0.02 -0.31 0.04 -0.01 0.28 Cu ppm 17.95 0.28

1 0.04 0 0 -0.09 0 Fe % 1.87 335.35

1 0.06 -0.31 -0.12 0.17 Mn ppm 91.43 1.66

1 0.01 -0.02 0.87 Ba ppm 1073.15 7.81

1 -0.01

1 -0.05

1

TOC % 2.87 2390.21

TS % 0.09 27.95

Sc ppm 14.19 3157.06

1 0 0.05 0.04

1 0.06 0

1 0.01

1

Ba ppm 1168.81 8.51

TOC % 1.86 1545.31

TS % 0.16 49.67

Sc ppm 22.18 4934.31

Xiaotan section: 2nd black shale succession (excl. metal-enriched layer) R2, n = 43 Mo V U Ni Cu Fe Mn Ba TOC TS Sc Element Average Ratio

1 0.07 0.44 0 0.02 -0.01 -0.04 0.04 0.04 0.04 0.05 Mo ppm 7.93 0.08

1 0.14 0.13 0.26 -0.01 0.21 0 0.08 0 0.24 V ppm 163.00 3.20

1 0 0.1 0.05 0 0.52 0.05 0.05 0.07 U ppm 4.05 0.02

1 0.15 0.09 0.36 -0.05 0.07 0.04 0.06

1 0.09 0.36 0.03 0.07 0.23 0.19

1 0.06 0.04 -0.05 0.21 0

Ni ppm 28.71 0.49

Cu ppm 17.94 0.28

Fe % 2.13 381.06

268

1 0 0 0.05 0.47 Mn ppm 137.52 2.50

Xiaotan section: 3rd black shale succession R2, n = 8 Mo V U Ni Cu Fe Mn Ba TOC TS Sc Inorg. C Element Average Ratio

1 0.63 0.3 -0.01 -0.14 -0.3 0.41 0.18 0.99 -0.23 0.07 -0.29 Mo ppm 20.60 0.21

1 0.19 0.23 0 -0.04 -0.39 0.23 0.58 -0.31 0.21 -0.23

1 0.05 0 -0.11 0.16 0 0.32 -0.16 0.34 -0.11

1 0.44 0.28 -0.05 0.03 -0.02 -0.04 0.35 -0.03

V ppm 463.69 9.10

U ppm 8.80 0.04

Ni ppm 55.66 0.95

1 0.42 -0.08 0.24 -0.11 0.11 0.3 -0.05 Cu ppm 21.11 0.33

1 -0.03 0.07 -0.29 0.14 0.16 -0.1 Fe % 3.53 632.87

1 0.67 -0.46 0 -0.42 0.93 Mn ppm 607.73 11.06

1 0.21 0.01 0.27 -0.53

1 -0.19 0.09 -0.33

1 -0.09 -0.03

1 -0.37

Ba ppm 1291.31 9.40

TOC % 2.43 2024.92

TS % 0.19 60.74

Sc ppm 28.57 6354.78

1 0.21 0.57 0.6 -0.08

1 0.29 0.45 -0.54

1 0.53 -0.17

1 -0.58

Ba ppm 1148.50 8.36

TOC % 4.51 3758.78

TS % 3.28 1023.82

Sc ppm 8.81 1960.75

Jijiawan section: Early Cambrian (JJL1a-10) R2, n = 9 Mo V U Ni Cu Fe Mn Ba TOC TS Sc Inorg. C Element Average Ratio

1 0.98 0.31 0.85 0.64 0.32 -0.01 0.95 0.36 0.64 0.68 -0.13 Mo ppm 51.07 0.53

1 0.24 0.82 0.6 0.27 -0.03 0.97 0.33 0.55 0.67 -0.14

1 0.24 0.5 0.89 0.54 0.23 0.44 0.79 0.29 -0.24

1 0.67 0.3 -0.01 0.73 0.53 0.43 0.63 -0.2

V ppm 225.15 4.42

U ppm 30.89 0.13

Ni ppm 104.31 1.78

1 0.69 0.01 0.5 0.65 0.64 0.92 -0.63 Cu ppm 14.86 0.23

269

1 0.33 0.23 0.55 0.74 0.47 -0.51 Fe % 2.40 429.66

1 -0.02 0.05 0.19 -0.02 0 Mn ppm 229.27 4.17

High resolution geochemical profiles from the LA-ICP-MS analysis The following profiles (MI1-7) show a restricted range of elements and the full processed dataset can be found in the attached CD-ROM.

MI 1

270

MI2

271

MI3

272

MI4

273

MI5

274

MI6

275

MI7

276

Raw elemental and isotopic data Element concentrations are from XRF (including major elements), ICP-MS measurements (without major elements whereas Fe (%) is taken from the AAS) and the C/S analyser. The samples from the Longbizui section have been analysed on a Finnigan Element 2 ICP-MS by Chen Xi at the University of Bristol. Changxingpo Mine, Guizhou Province Sample Distance (m) Formation CXP1 0.00 Tiesiao CXP2 0.40 Tiesiao CXP3 0.60 Tiesiao CXP4 0.80 Datangpo CXP8 0.90 Datangpo CXP9 1.00 Datangpo CXP10 1.25 Datangpo CXP11 1.45 Datangpo CXP12 1.50 Datangpo CXP13 1.60 Datangpo CXP14 1.75 Datangpo CXP15 1.90 Datangpo CXP16 2.15 Datangpo CXP17 2.25 Datangpo Upper Continental Crust

Position: 27°34'10.49"N, 109°23'7.95"E Lithology Si (%) Al (%) Diamictite 29.61 6.58 Diamictite 30.06 5.96 Diamictite 6.31 1.17 Carbonaceous Marl 15.58 6.58 Carbonaceous Marl 13.43 6.69 Carbonaceous Marl 28.92 7.81 Mn-carbonate Mn-carbonate 18.50 7.87 Mn-carbonate 17.80 8.60 Mn-carbonate 10.28 5.47 Mn-carbonate 8.08 4.00 Mn-carbonate 10.82 3.87 Mn-carbonate 13.71 3.68 Mn-carbonate 8.29 3.82 30.80 8.04

Maoshi section, Guizhou Province Sample Distance (m) Formation MS108 0 Dengying MS107 1 Dengying MS102 4.2 Dengying MS100 7 upper DST MS1 9 upper DST MS2 9.4 upper DST MS3 9.9 upper DST MS4 10.9 upper DST MS5 11.5 upper DST MS6 12.1 upper DST MS7 12.7 upper DST MS8 13.5 upper DST MS9 15 upper DST MS10 16 upper DST MS11 18 upper DST MS12 19 upper DST Average DST Upper Continental Crust

Position: 27°48'7.64"N / 106°43'58.10"E Lithology Si (%) Al (%) Dark carbonate Dark carbonate Dark carbonate Sandy shale 31.67 6.62 Black shale 30.74 6.93 Black shale 29.36 6.89 Black shale 31.63 6.80 Black shale 28.02 7.12 Black shale 29.89 6.51 Black shale 29.33 6.75 Black shale 27.41 6.66 Black shale 27.02 6.61 Black shale 26.74 6.76 Black shale 27.11 6.65 Black shale 28.01 5.95 Black shale 32.07 6.41 28.94 6.67 30.80 8.04

277

Fe (%) 1.53 1.70 4.56 4.15 4.41 2.53 2.05 1.94 1.68 1.43 1.61 2.11 1.90 3.50

Fe (%)

1.37 1.07 2.29 0.65 2.17 0.85 1.14 2.73 2.32 2.93 3.24 3.53 0.45 1.95 3.50

Changxingpo Mine, Guizhou Province Sample Mg (%) Ca (%) CXP1 0.50 8.89 CXP2 0.48 8.05 CXP3 2.16 1.58 CXP4 4.51 8.88 CXP8 2.92 9.03 CXP9 0.76 10.54 CXP10 CXP11 1.19 10.62 CXP12 1.25 11.61 CXP13 1.51 7.38 CXP14 1.73 5.40 CXP15 1.54 5.23 CXP16 1.62 4.96 CXP17 1.89 5.16 UCC 1.33 3.00 Maoshi section, Guizhou Province Sample Mg (%) Ca (%) MS108 MS107 MS102 MS100 0.91 8.94 MS1 0.86 9.36 MS2 0.82 9.30 MS3 0.78 9.18 MS4 0.83 9.62 MS5 0.71 8.79 MS6 0.73 9.11 MS7 0.72 8.99 MS8 0.70 8.92 MS9 0.72 9.13 MS10 0.79 8.98 MS11 0.72 8.03 MS12 0.81 8.66 Avg. DST 0.77 9.01 UCC 1.33 3.00

Na (%)

K (%)

P (%)

TC (%)

1.54 1.51 -0.01 0.42 0.53 2.26

2.01 1.75 0.02 0.89 1.44 2.20

0.25 0.18 0.05 0.15 0.08 0.11

0.35 0.39 0.12 0.10 0.25 0.22 0.17 2.89

3.15 3.47 2.11 1.46 1.37 1.03 1.18 2.80

0.08 0.14 0.24 0.22 0.18 0.13 0.20 0.07

Na (%)

K (%)

0.04 0.04 0.08 0.06 0.05 0.06 0.04 0.05 0.05 0.61 0.79 0.70 0.82 0.28 2.89

278

P (%)

5.23 5.54 5.63 5.54 5.67 5.34 5.68 5.52 5.54 4.80 4.26 3.58 3.93 5.09 2.80

0.89 1.11 7.62 3.01 3.90 2.16 1.50 4.45 4.00 7.06 8.48 7.39 6.25 7.90

TC (%)

0.45 0.47 0.31 0.14 0.40 0.33 0.50 0.68 0.84 0.44 0.76 0.66 0.02 0.46 0.07

10.28 12.70 12.67 0.52 1.08 1.37 1.75 2.07 3.32 2.73 2.69 3.03 3.67 2.76 2.14 2.50 2.43

Changxingpo Mine, Guizhou Province Sample TS (%) TOC (%) CXP1 1.12 0.12 CXP2 1.52 0.18 CXP3 5.56 0.71 CXP4 0.72 0.10 CXP8 2.44 0.11 CXP9 2.81 1.81 CXP10 3.58 0.65 CXP11 1.84 1.59 CXP12 1.38 1.42 CXP13 0.73 3.32 CXP14 0.47 3.17 CXP15 0.97 1.90 CXP16 1.15 1.09 CXP17 0.82 2.67 UCC

Pyrite S (%) 0.61 0.76 0.94 0.55 0.69 0.77 1.18 0.41 0.35 0.19 0.18 0.24 0.40 0.19

Maoshi section, Guizhou Province Sample TS (%) TOC (%) MS108 0.09 MS107 0.00 MS102 0.00 MS100 0.03 MS1 0.18 MS2 2.25 MS3 0.04 MS4 1.18 MS5 0.04 MS6 0.05 MS7 2.82 MS8 2.31 MS9 3.25 MS10 2.47 MS11 2.47 MS12 0.24 Avg. DST 1.44 UCC

Pyrite S (%) 0.00 0.00 0.16 0.01 0.11 1.73 0.01 0.74 0.01 0.01 2.18 1.70 2.53 0.96 1.64 0.14 0.98

0.32 0.49 0.43 0.49 1.05 1.32 1.72 1.95 3.37 2.70 2.61 2.98 3.62 2.72 2.15 2.60 2.40

279

34

δ S pyrite 42.68 42.30

Li (ppm) 17.76

Be (ppm) 1.43

28.59

130.71

1.17

25.73

2.14

30.77

2.70

20.00

3.00

20.56

59.26 55.02 52.95

34

δ S pyrite

-1.56845679

10.54137354

7.200314 7.081117387 11.3620454 11.9476106 13.9277852 18.53396881 9.88

Li (ppm)

Be (ppm)

Changxingpo Mine, Guizhou Province Sample Sc (ppm) Ti (ppm) CXP1 9.20 2305.27 CXP2 7.40 2128.96 CXP3 13.80 450.19 CXP4 14.40 2072.70 CXP8 16.30 3426.71 CXP9 11.90 3003.42 CXP10 15.60 921.61 CXP11 13.40 1349.48 CXP12 13.20 1551.46 CXP13 11.00 955.44 CXP14 9.70 899.66 CXP15 9.50 1407.78 CXP16 9.20 1597.69 CXP17 9.00 1743.54 UCC 13.60 4100.00 Maoshi section, Guizhou Province Sample Sc (ppm) Ti (ppm) MS108 8.10 MS107 7.30 MS102 9.30 MS100 12.00 4247.21 MS1 16.10 4667.42 MS2 17.40 4560.40 MS3 13.90 4739.39 MS4 17.80 4708.00 MS5 14.90 4586.09 MS6 17.10 4917.35 MS7 14.90 4122.73 MS8 14.90 4159.14 MS9 15.50 4311.63 MS10 14.00 4002.29 MS11 15.30 4056.82 MS12 9.40 4377.63 Avg. DST 15.10 4434.07 UCC 13.60 4100.00

V (ppm) 40.90 37.50 21.00 73.70 74.70 88.80 114.90 82.20 82.00 50.80 35.70 40.20 44.20 49.00 107.00

Cr (ppm) 19.10 17.20 5.80 26.30 39.00 38.10 55.00 34.90 35.70 25.10 19.60 22.50 21.80 23.50 83.00

Mn (ppm) 3838.16 4242.85 33163.00 23178.68 26317.46 2768.94 47552.94 52994.93 57958.15 135445.41 178476.72 148714.24 121294.67 174861.04 600.00

Co (ppm) 49.53

V (ppm)

Cr (ppm) 0.90 5.20 42.80 71.70 80.00 87.30 91.60 93.10 97.00 99.90 79.80 87.90 86.50 82.40 65.20 68.70 84.95 83.00

Mn (ppm)

Co (ppm)

3.00 7.20 42.60 71.30 94.70 94.20 95.50 107.00 104.80 103.60 91.80 88.10 92.80 79.40 72.00 81.00 92.08 107.00

280

59.41 51.61 58.13 44.00 71.82 35.74 28.69 100.11 99.52 148.10 121.60 78.45 29.08 72.24 600.00

10.43

53.94

73.82

17.00

17.00

Changxingpo Mine, Guizhou Province Sample Ni (ppm) Cu (ppm) CXP1 4.80 5.00 CXP2 5.40 4.90 CXP3 3.90 6.40 CXP4 10.00 8.80 CXP8 18.40 23.00 CXP9 54.70 41.10 CXP10 49.30 41.80 CXP11 63.60 55.70 CXP12 54.10 40.80 CXP13 45.90 22.70 CXP14 30.50 16.60 CXP15 32.00 22.00 CXP16 32.20 22.30 CXP17 33.50 26.20 UCC 44.00 25.00

Zn (ppm) 14.90 13.50 23.70 518.00 116.20 86.30 306.00 511.50 367.60 125.00 120.10 117.20 86.90 94.30 71.00

Ga (ppm) 15.10 12.70 5.50 21.30 19.80 16.00 21.90 14.20 14.10 10.60 7.00 7.20 8.00 7.30 17.00

Rb (ppm) 92.20 80.50 1.30 46.00 73.20 100.30 130.00 153.00 168.10 111.10 79.40 74.20 57.90 70.20 112.00

Sr (ppm) 128.70 130.10 508.80 292.40 263.90 98.00 123.60 156.50 152.70 197.50 187.20 179.30 208.10 191.30 350.00

Maoshi section, Guizhou Province Sample Ni (ppm) Cu (ppm) MS108 2.00 0.00 MS107 5.70 0.00 MS102 25.60 18.90 MS100 7.40 6.50 MS1 8.60 5.30 MS2 17.00 21.30 MS3 4.80 2.20 MS4 25.90 33.60 MS5 10.00 4.70 MS6 3.70 7.40 MS7 22.90 48.00 MS8 17.90 32.00 MS9 23.90 47.30 MS10 28.90 45.10 MS11 29.00 29.50 MS12 4.20 3.40 Avg. DST 16.40 23.32 UCC 44.00 25.00

Zn (ppm) 0.40 19.50 30.10 17.00 35.10 48.20 12.70 167.80 13.00 11.10 102.40 87.50 60.60 169.90 124.30 9.50 70.18 71.00

Ga (ppm) 0.20 1.40 12.90 15.20 17.60 16.20 17.20 18.40 17.00 17.70 15.80 15.30 15.40 15.30 15.10 15.30 16.36 17.00

Rb (ppm) 0.50 9.70 78.50 92.40 97.40 94.50 95.80 100.50 94.30 96.40 90.60 90.70 84.80 80.30 77.20 88.00 90.88 112.00

Sr (ppm) 45.30 135.80 163.50 49.60 42.60 34.10 20.60 39.10 24.40 26.80 67.30 76.30 70.10 122.50 93.40 32.60 54.15 350.00

281

Changxingpo Mine, Guizhou Province Sample Y (ppm) Zr (ppm) CXP1 9.80 181.00 CXP2 8.80 163.30 CXP3 4.20 71.10 CXP4 11.80 189.70 CXP8 28.00 353.60 CXP9 19.30 208.60 CXP10 19.20 278.00 CXP11 10.80 105.20 CXP12 12.80 118.40 CXP13 8.80 78.90 CXP14 9.10 70.80 CXP15 14.50 90.10 CXP16 15.70 98.20 CXP17 16.00 112.10 UCC 22.00 190.00

Nb (ppm) 5.20 5.00 1.20 5.80 13.90 11.40 13.20 6.20 7.90 5.10 4.30 5.80 8.10 7.50 12.00

Mo (ppm) 1.15 1.30 2.47 3.01 5.34 28.60 14.04 13.01 6.80 4.18 4.23 5.27 5.75 5.60 1.50

Cd (ppm) 0.05

Sn (ppm) 1.61

1.78

2.51

1.43

2.77

0.71

1.77

0.01

5.50

Maoshi section, Guizhou Province Sample Y (ppm) Zr (ppm) MS108 0.00 0.10 MS107 0.90 22.50 MS102 8.20 160.60 MS100 22.20 194.50 MS1 24.60 202.10 MS2 20.50 201.50 MS3 11.00 194.40 MS4 22.00 196.80 MS5 9.70 194.40 MS6 9.30 209.50 MS7 32.80 153.20 MS8 36.80 161.80 MS9 28.40 172.40 MS10 45.80 169.90 MS11 49.50 195.20 MS12 15.80 219.20 Avg. DST 25.52 189.20 UCC 22.00 190.00

Nb (ppm) -0.80 0.90 5.10 10.40 11.60 11.10 11.70 11.70 11.80 12.60 10.10 10.20 10.50 9.80 10.20 11.10 11.03 12.00

Mo (ppm) 0.93 0.87 1.00 1.70 1.22 2.82 3.56 3.01 4.42 2.40 4.76 5.38 5.61 4.01 0.66 0.25 3.17 1.50

Cd (ppm)

282

Sn (ppm)

Changxingpo Mine, Guizhou Province Sample Cs (ppm) Ba (ppm) CXP1 4.39 658.80 CXP2 581.20 CXP3 40.50 CXP4 2.74 380.20 CXP8 556.40 CXP9 707.20 CXP10 5.43 797.10 CXP11 1140.90 CXP12 1252.60 CXP13 3.98 939.80 CXP14 764.90 CXP15 667.10 CXP16 474.50 CXP17 624.40 UCC 4.60 550.00

La (ppm) 27.90 22.10 19.40 38.50 43.10 27.80 32.60 38.90 35.00 124.00 80.30 37.50 25.70 65.50 30.00

Ce (ppm) 56.90 44.40 45.90 72.60 100.70 59.00 63.30 89.20 90.20 285.70 171.30 78.10 56.80 128.20 64.00

Pr (ppm) 6.66

Maoshi section, Guizhou Province Sample Cs (ppm) Ba (ppm) MS108 8.80 MS107 60.20 MS102 510.30 MS100 739.20 MS1 811.70 MS2 864.00 MS3 874.60 MS4 872.70 MS5 929.80 MS6 967.90 MS7 804.00 MS8 840.70 MS9 800.30 MS10 738.60 MS11 640.40 MS12 720.40 Avg. DST 822.09 UCC 550.00

La (ppm) 0.00 3.50 17.40 19.90 17.20 21.20 12.80 13.70 6.40 4.80 24.50 28.70 18.70 36.60 39.60 9.90 19.51 30.00

Ce (ppm) 1.60 6.30 33.20 35.10 42.00 40.90 22.00 33.40 10.60 5.60 45.80 56.10 37.20 64.00 83.40 16.70 38.14 64.00

Pr (ppm)

283

7.90

9.41

34.49

7.10

7.10

Nd (ppm) 29.70 22.30 24.20 30.80 44.70 23.40 24.20 32.60 34.80 98.80 63.80 29.50 22.30 43.30 26.00

Nd (ppm) 2.50 5.00 21.80 20.10 24.80 20.30 12.20 23.70 5.70 5.00 28.70 33.40 22.10 35.10 48.70 6.90 22.22 26.00

Changxingpo Mine, Guizhou Province Sample Sm (ppm) Eu (ppm) CXP1 5.77 1.31 CXP2 CXP3 CXP4 6.31 1.32 CXP8 CXP9 CXP10 7.41 1.75 CXP11 CXP12 CXP13 22.26 4.44 CXP14 CXP15 CXP16 CXP17 UCC 4.50 0.88 Maoshi section, Guizhou Province Sample Sm (ppm) Eu (ppm) MS108 MS107 MS102 MS100 MS1 MS2 MS3 MS4 MS5 MS6 MS7 MS8 MS9 MS10 MS11 MS12 Avg. DST UCC

Gd (ppm) 4.93

Tb (ppm) 0.62

Dy (ppm) 3.50

Ho (ppm) 0.61

6.13

0.80

4.90

0.81

7.75

1.10

7.42

1.47

19.63

2.30

13.91

2.59

3.80

0.64

3.50

0.80

Gd (ppm)

284

Tb (ppm)

Dy (ppm)

Ho (ppm)

Changxingpo Mine, Guizhou Province Sample Er (ppm) Tm (ppm) CXP1 1.55 0.20 CXP2 CXP3 CXP4 2.04 0.25 CXP8 CXP9 CXP10 4.23 0.57 CXP11 CXP12 CXP13 6.94 0.90 CXP14 CXP15 CXP16 CXP17 UCC 2.30 0.33 Maoshi section, Guizhou Province Sample Er (ppm) Tm (ppm) MS108 MS107 MS102 MS100 MS1 MS2 MS3 MS4 MS5 MS6 MS7 MS8 MS9 MS10 MS11 MS12 Avg. DST UCC

Yb (ppm) 1.08

Lu (ppm) 0.18

Hf (ppm) 0.57

Ta (ppm) 0.22

1.42

0.22

0.42

0.49

3.65

0.57

0.75

0.22

5.09

0.73

0.44

0.17

2.20

0.32

5.80

1.00

Yb (ppm)

285

Lu (ppm)

Hf (ppm)

Ta (ppm)

Changxingpo Mine, Guizhou Province Sample W (ppm) Pb (ppm) CXP1 138.88 9.60 CXP2 10.50 CXP3 16.60 CXP4 36.99 10.70 CXP8 31.50 CXP9 39.00 CXP10 30.58 34.30 CXP11 14.20 CXP12 11.00 CXP13 13.57 9.30 CXP14 7.30 CXP15 9.40 CXP16 12.50 CXP17 8.80 UCC 2.00 17.00 Maoshi section, Guizhou Province Sample W (ppm) Pb (ppm) MS108 0.00 MS107 0.80 MS102 9.50 MS100 14.00 MS1 15.40 MS2 16.50 MS3 10.00 MS4 16.40 MS5 7.80 MS6 10.10 MS7 12.10 MS8 10.30 MS9 11.00 MS10 10.20 MS11 12.50 MS12 2.40 Avg. DST 11.23 UCC 17.00

Bi (ppm) 0.11

0.14

0.13

0.08

0.00

Bi (ppm)

286

Th (ppm) 30.70 25.50 31.10 43.10 69.80 33.80 28.90 44.00 58.40 111.20 112.20 81.10 67.60 81.50 10.70

U (ppm)

Th (ppm) 1.30 9.00 41.80 5.90 5.90 6.50 6.10 6.40 5.70 6.50 4.90 4.70 5.10 5.20 5.90 4.00 5.58 10.70

U (ppm)

Mo/Sc 0.87

0.12 0.18 0.18 0.21 0.33 2.40 0.90 0.97 0.52 0.38 0.44 0.55 0.62 0.62

0.89

1.73

1.19

2.80

Mo/Sc 0.11 0.12 0.11 0.14 0.08 0.16 0.26 0.17 0.30 0.14 0.32 0.36 0.36 0.29 0.04 0.03 0.21 0.11

Changxingpo Mine, Guizhou Province Sample V/Sc U/Sc CXP1 4.45 0.09 CXP2 5.07 CXP3 1.52 CXP4 5.12 0.06 CXP8 4.58 CXP9 7.46 CXP10 7.37 0.11 CXP11 6.13 CXP12 6.21 CXP13 4.62 0.11 CXP14 3.68 CXP15 4.23 CXP16 4.80 CXP17 5.44 UCC 0.21 Maoshi section, Guizhou Province Sample V/Sc U/Sc MS108 0.37 MS107 0.99 MS102 4.58 MS100 5.94 MS1 5.88 MS2 5.41 MS3 6.87 MS4 6.01 MS5 7.03 MS6 6.06 MS7 6.16 MS8 5.91 MS9 5.99 MS10 5.67 MS11 4.71 MS12 8.62 Avg. DST 6.19 UCC 7.87

Mo/TOC (10-4)

9.94 7.14 3.47 30.77 47.31 15.77 21.59 8.21 4.77 1.26 1.34 2.78 5.30 2.09

V/TOC (10-4)

Th/U

354.42 205.59 29.51 752.81 662.23 48.95 176.66 51.86 57.58 15.31 11.27 21.19 40.74 18.33

V/(V+Ni)

35.18

0.89 0.87 0.84 0.88 0.80 0.62 0.70 0.56 0.60 0.53 0.54 0.56 0.58 0.59 0.71

48.35

16.67

93.80

3.82

Mo/TOC (10-4)

2.92 1.77 2.33 3.45 1.16 2.13 2.06 1.54 1.31 0.89 1.82 1.80 1.55 1.48 0.30 0.10 1.35

287

V/TOC (10-4)

9.45 14.68 98.98 144.51 90.18 71.19 55.37 54.91 31.13 38.37 35.14 29.54 25.66 29.24 33.45 31.15 43.78

Th/U

V/(V+Ni)

0.60 0.56 0.62 0.91 0.92 0.85 0.95 0.81 0.91 0.97 0.80 0.83 0.80 0.73 0.71 0.95 0.85 0.71

Jiulongwan section, Hubei Province Sample Distance (m) Formation JLW1 0 DST II JLW2 0.7 DST II JLW3 1.3 DST II JLW4 2.3 DST II JLW5 2.8 DST II JLW6 4 DST II JLW7 6 DST II JLW8 7 DST II JLW9 8.5 DST II JLW10 10 DST II JLW11 11 DST II JLW12 13.5 DST II JLW13 18.5 DST II JLW14 20 DST II JLW15 20.8 DST II JLW16 20.7 DST II JLW17 27 DST II JLW18 27.7 DST II JLW19 28.7 DST II JLW20 30.2 DST II JLW21 31.3 DST II JLW22 34 DST II JLW23 37 DST II JLW24 45 DST II JLW25 49 DST II JLW26 53 DST II JLW27 58 DST II JLW28 60.5 DST II JLW29 61.1 DST II JLW30 66 DST II JLW31 66.9 DST II Average in black shale Upper Continental Crust

Position: 30°48'23.91"N, 111° 3'14.76"E Lithology Si (%) Al (%) Dolomite Dolomite Dolomitic black shale Dolomitic black shale Dolomite Dolomite Dolomite Dolomite Dolomite Dolomitic black shale Dolomitic black shale Dolomitic black shale Dolomitic black shale Dolomitic black shale Dolomitic black shale Dolomitic black shale Dolomitic black shale Dolomitic black shale Dolomitic black shale Dolomitic black shale Dolomitic black shale Dolomitic black shale Dolomitic black shale Dolomitic black shale Dolomitic black shale Dolomitic black shale Dolomitic black shale Dolomitic black shale Dolomitic black shale Dolomitic black shale Dolomitic black shale

288

Fe (%) 1.76 0.84 2.23 2.13 1.38 0.80 1.97 2.15 0.52 1.24 1.83 2.47 0.59 0.88 1.65 0.92 2.53 1.11 0.56 0.96 1.41 1.31 0.76 1.45 1.23 0.68 2.20 1.34 1.51 1.37 1.45 1.39 3.50

Jiulongwan section, Hubei Province Sample Mg (%) Ca (%) JLW1 JLW2 JLW3 JLW4 JLW5 JLW6 JLW7 JLW8 JLW9 JLW10 JLW11 JLW12 JLW13 JLW14 JLW15 JLW16 JLW17 JLW18 JLW19 JLW20 JLW21 JLW22 JLW23 JLW24 JLW25 JLW26 JLW27 JLW28 JLW29 JLW30 JLW31 Avg. BS UCC

Na (%)

K (%)

P (%)

TC (%) 5.66 7.13 7.30 6.90 6.21 9.94 7.06 7.03 8.60 6.46 9.14 7.24 8.22 7.63 6.71 7.08 6.39 8.11 7.61 8.92 7.76 7.18 7.48 8.21 7.97 9.17 8.62 6.77 6.83 6.74 7.77 7.54

289

Jiulongwan section, Hubei Province Sample TS (%) TOC (%) JLW1 1.56 JLW2 0.64 JLW3 2.21 JLW4 1.88 JLW5 1.11 JLW6 0.41 JLW7 0.87 JLW8 1.43 JLW9 0.28 JLW10 0.65 JLW11 0.31 JLW12 1.87 JLW13 0.14 JLW14 0.09 JLW15 1.17 JLW16 0.49 JLW17 1.71 JLW18 0.73 JLW19 1.46 JLW20 0.02 JLW21 0.11 JLW22 0.04 JLW23 0.08 JLW24 0.77 JLW25 0.63 JLW26 0.38 JLW27 2.28 JLW28 0.09 JLW29 0.86 JLW30 0.75 JLW31 1.09 Avg. BS 0.84 UCC

0.86 0.13 2.03 1.11 0.84 0.13 0.32 0.96 0.43 1.08 1.28 2.72 1.15 0.63 0.84 0.50 1.40 1.50 1.24 0.60 0.61 0.49 0.34 0.78 0.50 0.85 0.57 0.73 1.00 1.84 2.15 0.96

Pyrite S (%) 1.05 0.52 1.60 1.38 0.83 0.38 0.69 1.14 0.25 0.60 0.28 1.60 0.13 0.02 1.04 0.43 1.49 0.62 1.26 0.02 0.04 0.05 0.08 0.67 0.51 0.29 1.88 0.08 0.72 0.60 0.86 0.68

290

34

δ S pyrite 21.88 20.37 19.18 20.79 22.93 12.68 8.49 0.14 10.04 12.21 7.75 22.59

6.41 13.97 3.32 9.08 13.01

17.56 8.70 6.23 11.05 19.33 7.92 3.91 21.67 19.84 13.12

Li (ppm) 44.21 17.49 46.01 53.35 37.75 37.64 122.65 126.49 25.30 65.91 27.23 93.14 37.89 51.72 69.28 29.97 158.83 79.33 75.16 49.91 66.92 57.46 24.42 61.44 37.52 54.25 53.03 50.93 65.39 84.40 68.92 60.45 20.00

Be (ppm) 0.84 0.21 0.74 0.66 0.31 0.24 0.56 0.63 0.12 0.86 0.09 0.85 0.25 0.18 0.51 0.25 0.94 0.31 0.37 0.27 0.33 0.23 0.17 0.32 0.25 0.25 0.37 0.39 0.57 0.63 0.58 0.43 3.00

Jiulongwan section, Hubei Province Sample Sc (ppm) Ti (ppm) JLW1 11.43 2712.24 JLW2 6.15 844.82 JLW3 9.66 3017.97 JLW4 8.69 2814.02 JLW5 5.63 1524.57 JLW6 3.62 1151.13 JLW7 7.32 2622.35 JLW8 7.67 2596.64 JLW9 2.25 502.69 JLW10 11.76 1158.09 JLW11 2.26 445.57 JLW12 10.35 4056.03 JLW13 2.87 634.48 JLW14 2.71 715.63 JLW15 5.46 1618.43 JLW16 2.25 664.17 JLW17 11.46 3779.23 JLW18 4.70 1437.82 JLW19 5.67 1908.09 JLW20 1.96 364.64 JLW21 2.95 1056.23 JLW22 2.69 962.63 JLW23 1.07 416.26 JLW24 4.49 1625.69 JLW25 2.93 1101.15 JLW26 1.95 683.41 JLW27 4.08 1218.53 JLW28 4.79 1446.73 JLW29 6.41 1797.09 JLW30 7.44 2760.60 JLW31 6.92 1800.32 Avg. BS 5.47 1594.75 UCC 13.60 4100.00

V (ppm) 62.46 17.92 80.90 78.04 47.10 24.84 48.46 51.47 17.19 40.46 17.28 67.97 55.89 20.43 37.51 15.63 69.66 37.86 38.13 15.68 20.03 17.62 8.53 30.57 18.38 15.13 27.51 30.45 68.28 43.96 34.14 37.40 107.00

291

Cr (ppm) 21.48 16.60 34.30 47.81 22.67 20.82 29.24 28.07 14.23 53.55 15.32 43.11 19.71 17.75 23.57 8.96 36.07 21.48 24.96 14.54 12.68 17.54 7.54 19.58 24.88 28.66 27.59 23.04 37.95 35.60 30.10 25.14 83.00

Mn (ppm) 981.13 1342.29 1247.62 1002.54 1191.89 2361.08 508.50 495.08 761.18 740.43 827.18 408.22 283.45 270.14 284.33 277.90 306.61 342.73 346.74 307.25 244.99 214.71 297.39 273.84 245.52 174.98 206.29 232.77 271.63 161.44 226.25 543.10 600.00

Co (ppm) 16.71 20.62 13.62 12.97 11.69 6.33 9.57 9.74 4.85 11.11 6.97 13.58 7.29 5.85 8.44 5.65 15.74 6.96 7.49 4.31 4.13 4.35 4.58 7.48 5.30 3.50 7.52 6.40 8.30 8.34 7.63 8.61 17.00

Jiulongwan section, Hubei Province Sample Ni (ppm) Cu (ppm) JLW1 14.30 12.17 JLW2 5.90 5.27 JLW3 29.99 21.12 JLW4 31.55 17.54 JLW5 16.15 11.06 JLW6 12.26 7.02 JLW7 24.45 14.68 JLW8 25.23 14.56 JLW9 7.56 4.33 JLW10 18.08 9.84 JLW11 7.78 4.13 JLW12 35.18 18.23 JLW13 13.78 7.50 JLW14 9.24 6.69 JLW15 25.11 12.20 JLW16 10.21 4.76 JLW17 40.73 21.21 JLW18 21.19 13.01 JLW19 22.01 11.29 JLW20 7.97 4.38 JLW21 11.63 5.65 JLW22 16.65 5.20 JLW23 6.90 3.02 JLW24 18.50 10.13 JLW25 19.09 7.64 JLW26 17.65 4.68 JLW27 17.46 10.90 JLW28 12.58 9.95 JLW29 34.76 13.16 JLW30 21.29 12.84 JLW31 20.69 12.52 Avg. BS 18.58 10.21 UCC 44.00 25.00

Zn (ppm) 27.98 22.10 124.31 215.56 48.03 93.97 58.39 59.46 81.36 110.05 37.47 82.82 88.87 70.29 219.06 194.82 111.15 85.03 71.50 99.71 46.11 59.73 10.72 16.35 52.20 29.04 33.55 54.31 162.44 92.88 98.27 82.50 71.00

292

Ga (ppm) 11.55 2.67 8.61 7.93 4.84 3.22 7.45 7.48 1.63 5.86 1.72 10.45 3.03 2.89 4.87 2.65 10.51 4.62 5.21 1.42 4.07 4.43 0.95 4.40 3.24 3.79 4.16 4.79 6.35 6.12 5.00 5.03 17.00

Rb (ppm) 35.08 8.92 30.70 21.63 9.74 4.97 5.86 6.72 1.04 8.21 0.84 30.05 8.11 1.71 15.30 5.67 39.93 3.48 11.93 1.01 2.98 2.57 1.15 8.88 8.30 3.07 10.80 14.46 26.87 25.87 14.79 11.96 112.00

Sr (ppm) 46.28 94.95 228.21 231.72 169.76 288.82 270.87 264.75 293.70 312.52 288.40 332.84 595.93 685.52 618.99 599.09 609.82 871.81 667.81 917.21 630.47 710.85 605.68 498.77 383.31 463.60 404.14 298.88 295.22 389.05 481.46 437.11 350.00

Jiulongwan section, Hubei Province Sample Y (ppm) Zr (ppm) JLW1 6.48 30.42 JLW2 2.91 8.04 JLW3 14.18 39.01 JLW4 14.74 47.15 JLW5 8.86 30.33 JLW6 14.37 12.91 JLW7 10.70 23.15 JLW8 10.46 20.18 JLW9 5.94 7.27 JLW10 6.83 11.96 JLW11 5.84 7.35 JLW12 14.76 36.55 JLW13 4.51 10.18 JLW14 4.11 11.28 JLW15 6.46 17.00 JLW16 7.25 17.83 JLW17 13.38 31.17 JLW18 7.36 14.54 JLW19 6.34 17.09 JLW20 3.27 6.04 JLW21 5.39 24.56 JLW22 4.72 22.88 JLW23 2.23 9.41 JLW24 7.80 37.33 JLW25 5.15 25.73 JLW26 4.12 14.96 JLW27 6.51 14.61 JLW28 7.99 18.31 JLW29 12.07 20.38 JLW30 13.87 26.94 JLW31 9.39 21.07 Avg. BS 8.00 20.50 UCC 22.00 190.00

Nb (ppm) 4.92 0.23 4.94 4.40 2.32 1.84 4.27 3.99 1.08 2.12 1.10 6.76 0.96 1.30 2.65 1.27 6.21 1.94 2.56 0.59 1.89 1.77 0.77 2.80 2.08 1.27 1.95 2.17 3.51 4.16 3.06 2.61 12.00

293

Mo (ppm) 0.08 0.39 2.91 2.75 1.99 0.13 0.59 0.80 1.75 1.79 0.04 1.33 4.40 0.17 0.54 0.61 1.00 1.86 0.57 0.22 0.85 1.86 0.57 0.97 1.85 1.48 0.95 0.02 4.01 0.56 0.61 1.21 1.50

Cd (ppm) 0.05 0.08 0.43 0.16 0.04 0.05 0.03 0.07 0.12 0.18 0.00 0.13 0.29 0.02 0.06 0.20 0.07 0.06 0.05 0.01 0.07 0.01 0.00 0.00 0.02 0.04 0.02 0.04 0.38 0.11 0.09 0.09 0.0098

Sn (ppm) 1.14 0.43 1.19 1.13 0.69 0.70 0.80 0.76 0.41 5.84 0.41 1.09 0.56 0.46 0.80 0.19 1.11 0.87 0.65 0.46 0.19 0.26 0.07 0.35 0.23 0.19 0.52 1.00 0.87 1.04 1.14 0.82 5.50

Jiulongwan section, Hubei Province Sample Cs (ppm) Ba (ppm) JLW1 1.15 91.91 JLW2 0.40 60.16 JLW3 1.07 440.56 JLW4 5.38 288.89 JLW5 0.71 148.60 JLW6 0.61 398.19 JLW7 0.86 242.42 JLW8 0.62 245.05 JLW9 0.60 78.74 JLW10 4.52 247.68 JLW11 0.67 195.60 JLW12 1.24 358.46 JLW13 0.79 919.52 JLW14 0.73 1074.87 JLW15 3.52 718.63 JLW16 1.05 521.11 JLW17 2.37 568.05 JLW18 2.79 762.66 JLW19 2.12 326.13 JLW20 0.97 253.62 JLW21 0.70 347.42 JLW22 0.57 99.40 JLW23 0.95 118.11 JLW24 1.14 66.65 JLW25 1.34 50.04 JLW26 0.96 122.76 JLW27 1.18 91.46 JLW28 1.46 106.11 JLW29 1.85 307.19 JLW30 1.90 183.55 JLW31 1.04 166.04 Avg. BS 1.46 309.66 UCC 4.60 550.00

La (ppm) 10.45 4.30 17.02 14.79 6.74 35.27 13.48 13.16 13.90 16.42 14.77 19.23 6.99 6.39 7.90 15.82 14.70 10.83 6.85 2.98 5.56 4.74 2.74 7.59 4.36 2.20 4.63 7.18 13.80 13.83 11.38 10.65 30.00

294

Ce (ppm) 16.55 6.10 24.97 19.65 9.99 38.27 18.93 18.76 11.24 18.12 11.71 26.36 8.12 6.96 11.32 20.25 24.62 12.80 10.03 1.91 6.52 5.82 2.32 11.78 6.88 2.30 6.65 10.70 22.37 18.78 15.66 13.76 64.00

Pr (ppm) 2.76 1.12 4.34 3.27 1.75 6.39 3.14 3.08 2.13 3.17 2.14 4.11 1.57 1.54 1.91 4.12 3.74 2.21 1.72 0.67 1.33 1.10 0.65 1.94 1.15 0.63 1.27 1.90 3.72 3.25 2.79 2.41 7.10

Nd (ppm) 10.74 4.56 18.68 13.99 7.48 24.08 12.60 12.52 7.79 11.94 7.71 16.49 6.28 6.25 7.69 16.56 15.19 8.87 7.04 2.59 5.18 4.51 2.61 8.08 4.76 2.71 5.22 7.79 15.85 13.82 11.36 9.71 26.00

Jiulongwan section, Hubei Province Sample Sm (ppm) Eu (ppm) JLW1 2.15 0.50 JLW2 0.91 0.27 JLW3 3.66 0.78 JLW4 2.71 0.76 JLW5 1.43 0.36 JLW6 3.98 0.90 JLW7 2.32 0.68 JLW8 2.62 0.67 JLW9 1.35 0.34 JLW10 2.24 0.64 JLW11 1.31 0.35 JLW12 3.35 0.88 JLW13 1.17 0.37 JLW14 1.17 0.51 JLW15 1.42 0.47 JLW16 3.13 1.04 JLW17 3.14 0.79 JLW18 1.63 0.56 JLW19 1.49 0.40 JLW20 0.53 0.16 JLW21 1.06 0.32 JLW22 0.82 0.26 JLW23 0.52 0.16 JLW24 1.58 0.40 JLW25 0.94 0.23 JLW26 0.60 0.13 JLW27 1.16 0.26 JLW28 1.65 0.35 JLW29 3.03 0.65 JLW30 2.86 0.74 JLW31 2.14 0.55 Avg. BS 1.87 0.50 UCC 4.50 0.88

Gd (ppm) 1.86 0.77 3.34 2.66 1.46 3.56 2.39 2.40 1.24 1.92 1.23 3.26 1.06 1.11 1.39 2.54 3.14 1.71 1.40 0.57 1.01 0.87 0.48 1.52 1.07 0.60 1.22 1.65 2.92 2.90 2.20 1.79 3.80

295

Tb (ppm) 0.24 0.10 0.43 0.34 0.20 0.42 0.31 0.30 0.16 0.28 0.15 0.43 0.13 0.13 0.18 0.28 0.40 0.22 0.19 0.08 0.14 0.12 0.06 0.21 0.14 0.08 0.15 0.21 0.37 0.37 0.30 0.23 0.64

Dy (ppm) 1.43 0.60 2.65 2.26 1.40 2.49 1.97 1.89 0.96 1.77 0.98 2.73 0.81 0.77 1.21 1.48 2.61 1.34 1.15 0.53 0.93 0.79 0.42 1.45 0.92 0.54 1.04 1.41 2.16 2.36 1.90 1.45 3.50

Ho (ppm) 0.26 0.12 0.48 0.46 0.28 0.46 0.35 0.35 0.18 0.36 0.17 0.50 0.16 0.13 0.23 0.25 0.48 0.25 0.22 0.11 0.19 0.16 0.08 0.28 0.18 0.13 0.21 0.27 0.41 0.45 0.40 0.28 0.80

Jiulongwan section, Hubei Province Sample Er (ppm) Tm (ppm) JLW1 0.70 0.10 JLW2 0.32 0.04 JLW3 1.32 0.18 JLW4 1.32 0.17 JLW5 0.80 0.11 JLW6 1.22 0.16 JLW7 0.94 0.13 JLW8 0.99 0.13 JLW9 0.49 0.06 JLW10 1.08 0.13 JLW11 0.49 0.06 JLW12 1.31 0.17 JLW13 0.42 0.05 JLW14 0.36 0.05 JLW15 0.63 0.08 JLW16 0.65 0.08 JLW17 1.34 0.17 JLW18 0.69 0.09 JLW19 0.62 0.08 JLW20 0.29 0.04 JLW21 0.58 0.08 JLW22 0.44 0.07 JLW23 0.26 0.03 JLW24 0.83 0.11 JLW25 0.54 0.07 JLW26 0.37 0.05 JLW27 0.58 0.07 JLW28 0.74 0.10 JLW29 1.06 0.13 JLW30 1.24 0.16 JLW31 1.03 0.13 Avg. BS 0.76 0.10 UCC 2.30 0.33

Yb (ppm) 0.59 0.22 0.95 1.03 0.66 0.92 0.74 0.72 0.35 0.88 0.33 0.92 0.32 0.28 0.48 0.49 0.97 0.53 0.50 0.24 0.48 0.35 0.19 0.65 0.43 0.32 0.42 0.56 0.74 0.80 0.71 0.57 2.20

296

Lu (ppm) 0.09 0.04 0.15 0.15 0.10 0.13 0.12 0.11 0.06 0.11 0.05 0.14 0.05 0.05 0.08 0.07 0.14 0.09 0.07 0.03 0.06 0.06 0.02 0.10 0.07 0.05 0.06 0.08 0.11 0.11 0.09 0.09 0.32

Hf (ppm) 0.65 0.16 0.90 1.15 0.65 0.26 0.55 0.38 0.13 0.50 0.10 0.84 0.21 0.24 0.42 0.32 0.76 0.33 0.34 0.09 0.49 0.50 0.20 0.80 0.52 0.27 0.31 0.44 0.51 0.67 0.50 0.46 5.80

Ta (ppm) 0.40 0.07 0.37 0.37 0.13 0.22 0.60 0.38 0.18 0.31 0.35 0.55 0.15 0.13 0.31 0.13 0.51 0.14 0.15 0.11 0.17 0.15 0.13 0.22 0.15 0.19 0.24 0.09 0.23 0.26 0.23 0.25 1.00

Jiulongwan section, Hubei Province Sample W (ppm) Pb (ppm) JLW1 36.32 9.26 JLW2 101.03 6.18 JLW3 26.49 12.50 JLW4 17.57 10.58 JLW5 43.09 6.24 JLW6 18.55 10.63 JLW7 22.47 10.21 JLW8 11.90 7.02 JLW9 28.46 5.22 JLW10 77.75 22.53 JLW11 33.73 4.86 JLW12 21.83 9.26 JLW13 42.97 8.29 JLW14 29.76 7.53 JLW15 21.23 27.91 JLW16 26.48 1.58 JLW17 9.26 7.21 JLW18 11.89 7.61 JLW19 33.75 7.61 JLW20 41.68 6.20 JLW21 12.96 1.59 JLW22 10.91 1.48 JLW23 30.59 0.96 JLW24 7.34 2.90 JLW25 7.55 2.11 JLW26 7.60 1.01 JLW27 12.16 4.76 JLW28 16.86 7.99 JLW29 40.35 12.65 JLW30 18.11 8.59 JLW31 19.41 8.70 Avg. BS 27.10 7.78 UCC 2.00 17.00

Bi (ppm) 0.10 0.03 0.08 0.07 0.03 0.05 0.06 0.05 0.03 0.11 0.02 0.05 0.08 0.02 0.04 0.01 0.05 0.09 0.06 0.02 0.04 0.01 0.01 0.02 0.02 0.01 0.02 0.03 0.12 0.04 0.05 0.04 0.00127

297

Th (ppm) 1.57 0.48 2.00 1.84 1.03 0.54 1.38 1.35 0.24 1.63 0.19 1.88 0.92 0.46 1.14 0.57 1.60 0.94 0.74 0.19 0.64 0.60 0.21 1.12 0.82 0.40 0.65 1.00 1.66 1.59 1.37 0.99 10.70

U (ppm)

Mo/Sc 0.28 0.09 1.67 3.20 2.05 0.24 0.81 0.79 0.27 1.20 0.22 1.28 1.23 0.69 0.51 0.61 0.99 0.88 0.53 0.39 0.52 0.34 0.30 0.87 0.40 0.51 0.59 0.58 1.15 0.92 0.87 0.81 2.80

0.01 0.06 0.30 0.32 0.35 0.04 0.08 0.10 0.78 0.15 0.02 0.13 1.53 0.06 0.10 0.27 0.09 0.40 0.10 0.11 0.29 0.69 0.53 0.22 0.63 0.76 0.23 0.00 0.62 0.08 0.09 0.29 0.11

Jiulongwan section, Hubei Province Sample V/Sc U/Sc JLW1 5.47 JLW2 2.91 JLW3 8.37 JLW4 8.98 JLW5 8.37 JLW6 6.86 JLW7 6.62 JLW8 6.71 JLW9 7.64 JLW10 3.44 JLW11 7.63 JLW12 6.57 JLW13 19.49 JLW14 7.53 JLW15 6.87 JLW16 6.96 JLW17 6.08 JLW18 8.06 JLW19 6.72 JLW20 8.01 JLW21 6.80 JLW22 6.56 JLW23 7.94 JLW24 6.81 JLW25 6.27 JLW26 7.76 JLW27 6.74 JLW28 6.36 JLW29 10.65 JLW30 5.91 JLW31 4.93 Avg. BS 7.29 UCC 7.87

Mo/TOC (10-4)

0.02 0.01 0.17 0.37 0.36 0.07 0.11 0.10 0.12 0.10 0.09 0.12 0.43 0.25 0.09 0.27 0.09 0.19 0.09 0.20 0.18 0.13 0.28 0.19 0.14 0.26 0.14 0.12 0.18 0.12 0.13 0.17 0.21

0.09 2.97 1.43 2.48 2.38 1.02 1.82 0.83 4.04 1.66 0.03 0.49 3.83 0.27 0.64 1.23 0.71 1.24 0.46 0.37 1.39 3.77 1.68 1.25 3.70 1.73 1.67 0.03 4.00 0.30 0.28 1.54

298

V/TOC (10-4)

72.33 135.22 39.79 70.50 56.16 191.94 149.56 53.65 39.73 37.43 13.52 24.97 48.64 32.50 44.77 31.54 49.90 25.22 30.78 26.32 32.94 35.67 25.36 39.41 36.73 17.74 48.25 41.51 68.11 23.94 15.86 50.32

Th/U

V/(V+Ni)

5.55 5.48 1.20 0.57 0.50 2.23 1.70 1.71 0.88 1.36 0.88 1.48 0.75 0.67 2.25 0.93 1.62 1.06 1.41 0.49 1.22 1.77 0.71 1.29 2.03 0.79 1.10 1.73 1.44 1.73 1.58 1.55 3.82

0.81 0.75 0.73 0.71 0.74 0.67 0.66 0.67 0.69 0.69 0.69 0.66 0.80 0.69 0.60 0.60 0.63 0.64 0.63 0.66 0.63 0.51 0.55 0.62 0.49 0.46 0.61 0.71 0.66 0.67 0.62 0.66 0.71

Jiulongwan section, Hubei Province Sample Distance (m) Formation JLW40 0 Miaohe JLW41 0.35 Miaohe JLW42 0.95 Miaohe JLW43 1.65 Miaohe JLW44 2.15 Miaohe JLW45 2.65 Miaohe JLW46 3.25 Miaohe JLW47 3.75 Miaohe JLW48 4.25 Miaohe JLW49 4.85 Miaohe JLW50 5.55 Miaohe JLW51 5.95 Miaohe JLW52 6.55 Miaohe JLW53 7.35 Miaohe JLW54 7.75 Miaohe JLW55 8.25 Miaohe JLW56 8.85 Miaohe JLW58 9.7 Miaohe JLW59 10.4 Miaohe JLW60 12 Miaohe JLW61 13.05 DST III JLW62 14 DST III JLW63 15 DST III JLW64 16 DST III JLW65 17.55 DST III Average Miaohe: Upper Continental Crust

Position: 30°48'23.91"N, 111° 3'14.76"E Lithology Si (%) Al (%) Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Dolomite Dolomite Dolomite Dolomite Dolomite

Jijiawan section, Hubei Province Sample Distance (m) Formation JJ1 0 DST II JJ2 2 DST II JJ3 4 DST II JJ4 6 DST II JJ5 8.7 DST IV JJ6 9.2 DST IV JJ7 11.2 DST IV JJ8 12.5 DST IV JJ9 13.5 DST IV JJ10 16 DST IV JJ11 17.5 DST IV JJ12 18.5 DST IV Average Miaohe: Upper Continental Crust

Position: 30°53'0.93"N, 110°52'47.25"E Lithology Si (%) Al (%) Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale

299

Fe (%) 4.82 0.76 0.28 2.34 2.34 2.75 2.41 2.38 2.49 2.45 2.50 2.71 3.04 3.58 3.86 2.97 3.25 2.94 2.46 2.31 0.55 0.55 0.27 0.35 0.30 2.52 3.50

Fe (%) 3.24 1.55 1.86 1.57 0.96 1.53 1.29 0.18 1.07 1.01 1.21 1.96 1.15 3.50

Jiulongwan section, Hubei Province Sample Mg (%) Ca (%) JLW40 JLW41 JLW42 JLW43 JLW44 JLW45 JLW46 JLW47 JLW48 JLW49 JLW50 JLW51 JLW52 JLW53 JLW54 JLW55 JLW56 JLW58 JLW59 JLW60 JLW61 JLW62 JLW63 JLW64 JLW65 Avg. BS UCC Jijiawan section, Hubei Province Sample Mg (%) Ca (%) JJ1 JJ2 JJ3 JJ4 JJ5 JJ6 JJ7 JJ8 JJ9 JJ10 JJ11 JJ12 Avg. BS UCC

Na (%)

K (%)

P (%)

TC (%) 1.42 15.40 13.53 8.88 7.57 6.64 6.86 7.79 6.34 6.43 5.69 5.23 4.56 5.70 5.02 6.17 5.51 5.25 5.98 2.84 10.43 10.74 10.10 10.28 10.23 6.91

Na (%)

K (%)

P (%)

TC (%) 4.99 8.13 7.29 8.28 5.93 3.57 2.64 0.51 2.22 2.91 0.22 2.70 2.59

300

Jiulongwan section, Hubei Province Sample TS (%) TOC (%) JLW40 5.43 0.78 JLW41 1.24 14.94 JLW42 0.52 7.23 JLW43 2.76 5.00 JLW44 3.34 5.90 JLW45 3.50 5.48 JLW46 3.36 5.36 JLW47 3.32 5.94 JLW48 3.28 5.50 JLW49 3.46 5.39 JLW50 3.38 4.49 JLW51 3.30 4.48 JLW52 3.37 4.21 JLW53 5.70 4.28 JLW54 4.99 4.27 JLW55 3.70 5.24 JLW56 4.04 5.38 JLW58 3.72 4.61 JLW59 3.17 5.54 JLW60 2.77 2.03 JLW61 0.32 0.44 JLW62 0.19 0.19 JLW63 0.14 0.06 JLW64 0.17 0.05 JLW65 0.18 0.01 Avg. BS 3.31 5.54 UCC

Pyrite S (%) 4.62 0.51 0.18 2.04 2.21 2.60 2.12 2.16 2.13 2.38 2.42 2.55 2.57 3.66 3.50 2.63 2.74 2.74 1.65 1.31 0.38 0.28 0.19 0.23 0.24 2.22

δ S pyrite -7.12 -17.27 -19.03 -13.38

Jijiawan section, Hubei Province Sample TS (%) TOC (%) JJ1 1.34 JJ2 0.76 JJ3 0.90 JJ4 0.76 JJ5 1.53 JJ6 1.99 JJ7 1.45 JJ8 0.16 JJ9 1.26 JJ10 1.19 JJ11 1.22 JJ12 2.28 Avg. BS 1.38 UCC

Pyrite S (%) 0.82 0.45 0.69 0.91 0.41 1.15 0.73 0.09 0.79 0.74 0.89 1.49 0.79

δ S pyrite -10.51 9.58 9.42 13.58 19.04 20.18 23.20

1.91 4.03 3.53 0.84 5.63 3.33 2.55 0.55 2.14 2.61 0.25 2.44 2.44

301

34

-14.82 -11.45 -11.43 -10.51 -10.26 -9.10 -11.15 -10.19 -8.83 -6.93 -5.93 -7.79 -11.49 -8.68 -11.04 -7.04 -7.09 -11.20

34

17.57 16.70 21.12 11.23 18.43

Li (ppm) 83.82 8.86 13.46 33.09 37.77 38.89 38.98 31.23 37.17 27.75 119.53 35.34 33.37 31.62 33.38 29.64 16.33 48.75 26.65 37.64 8.59 4.81 11.15 2.73 2.50 35.76 20.00

Be (ppm) 3.40 0.34 0.11 1.62 1.87 1.83 1.88 1.86 2.22 1.89 6.42 2.18 1.95 2.05 1.94 1.94 0.80 2.91 1.78 2.42 0.75 0.74 0.35 0.30 0.24 2.00 3.00

Li (ppm) 106.37 105.72 70.11 67.89 18.67 17.54 17.58 14.24 16.08 18.03 17.85 49.62 21.20 20.00

Be (ppm) 0.89 0.92 0.55 0.52 0.41 0.77 0.71 0.18 0.72 0.59 0.58 1.42 0.67 3.00

Jiulongwan section, Hubei Province Sample Sc (ppm) Ti (ppm) JLW40 19.79 3882.21 JLW41 4.48 506.83 JLW42 2.63 193.09 JLW43 12.61 2047.60 JLW44 15.15 2464.11 JLW45 15.30 2508.35 JLW46 16.14 2448.15 JLW47 14.28 2305.01 JLW48 17.42 2226.15 JLW49 14.97 2229.58 JLW50 59.18 3541.92 JLW51 15.70 2760.93 JLW52 10.39 2531.18 JLW53 15.47 2433.24 JLW54 17.28 2548.11 JLW55 10.53 2513.80 JLW56 5.02 1141.15 JLW58 15.23 3864.74 JLW59 10.10 2691.77 JLW60 12.99 3075.41 JLW61 4.88 612.11 JLW62 3.57 502.03 JLW63 3.82 667.80 JLW64 2.42 379.53 JLW65 2.11 324.47 Avg. BS 14.99 2317.43 UCC 13.60 4100.00

V (ppm) 386.78 168.29 171.13 952.50 1393.17 1241.76 1380.27 1456.06 1492.82 1110.84 1604.43 1577.85 1141.18 1251.98 1231.34 796.70 421.43 2059.72 1351.50 2404.78 233.45 75.88 103.69 59.46 37.67 1221.46 107.00

Cr (ppm) 119.36 15.07 10.08 75.53 87.25 89.63 98.68 84.92 122.94 109.03 195.04 114.12 76.03 92.25 95.30 183.10 57.35 174.33 85.36 153.77 126.54 28.21 25.82 21.49 20.67 101.04 83.00

Mn (ppm) 74.58 60.36 252.37 284.95 237.07 191.03 263.19 286.27 234.10 231.88 857.39 192.90 117.45 301.26 239.59 225.47 91.38 290.97 176.01 151.64 180.35 153.34 130.08 64.75 51.09 246.59 600.00

Co (ppm) 9.41 11.38 4.50 13.34 15.21 15.31 15.36 14.92 13.87 13.25 15.61 15.91 12.77 14.06 18.74 10.65 5.76 18.49 13.02 12.94 15.28 6.54 6.66 5.04 3.86 13.43 17.00

Jijiawan section, Hubei Province Sample Sc (ppm) Ti (ppm) JJ1 9.12 3417.46 JJ2 4.37 1648.78 JJ3 4.31 1518.79 JJ4 5.71 1547.07 JJ5 7.21 1008.50 JJ6 11.26 1401.96 JJ7 14.73 1770.22 JJ8 4.94 211.07 JJ9 8.86 956.00 JJ10 15.32 826.09 JJ11 7.03 941.88 JJ12 10.98 2270.12 Avg. BS 10.04 1173.23 UCC 13.60 4100.00

V (ppm) 54.87 38.95 27.09 52.26 72.67 106.86 116.74 15.67 48.30 55.90 43.34 110.24 71.21 107.00

Cr (ppm) 30.55 72.30 58.88 26.64 52.92 68.00 80.20 20.91 62.19 56.98 39.33 96.79 59.66 83.00

Mn (ppm) 296.98 196.92 222.60 293.49 32.41 45.07 33.70 20.84 40.71 67.17 24.66 52.00 39.57 600.00

Co (ppm) 13.32 7.53 8.12 7.21 14.81 12.92 16.88 206.97 99.00 51.63 47.81 22.82 59.11 17.00

302

Jiulongwan section, Hubei Province Sample Ni (ppm) Cu (ppm) JLW40 25.01 24.80 JLW41 10.12 7.18 JLW42 10.43 2.25 JLW43 103.45 34.48 JLW44 154.43 45.54 JLW45 79.11 47.37 JLW46 178.65 60.62 JLW47 200.43 28.18 JLW48 172.90 86.93 JLW49 117.77 86.24 JLW50 166.68 90.37 JLW51 91.49 54.03 JLW52 67.04 39.66 JLW53 77.89 59.78 JLW54 81.76 49.04 JLW55 124.61 121.78 JLW56 36.23 29.52 JLW58 136.95 72.75 JLW59 80.17 38.80 JLW60 95.80 46.90 JLW61 59.74 8.00 JLW62 12.23 5.98 JLW63 18.22 8.24 JLW64 17.41 5.22 JLW65 8.90 4.16 Avg. BS 104.52 52.71 UCC 44.00 25.00

Zn (ppm) 45.98 130.62 20.10 205.80 364.04 130.02 560.40 254.25 541.85 307.55 803.49 117.65 70.94 195.43 194.83 422.80 51.90 202.31 87.51 63.22 56.34 34.57 84.27 25.49 29.96 248.67 71.00

Ga (ppm) 23.90 2.99 1.08 13.26 17.35 16.04 19.20 14.60 20.88 16.43 18.44 18.99 14.75 16.26 17.99 14.41 6.91 22.58 16.04 16.94 4.67 3.37 3.67 2.43 2.03 15.01 17.00

Rb (ppm) 187.18 17.04 5.62 88.72 111.41 116.95 105.04 95.69 123.30 107.48 141.07 135.54 110.61 119.24 136.14 94.15 46.34 149.03 107.05 134.02 27.58 20.17 22.18 14.13 12.48 102.34 112.00

Sr (ppm) 48.45 87.20 47.30 167.95 344.70 75.00 446.83 376.69 332.55 420.10 352.91 72.72 41.84 549.40 193.26 154.96 24.86 74.75 44.10 49.40 108.69 124.90 183.04 183.29 171.94 202.97 350.00

Jijiawan section, Hubei Province Sample Ni (ppm) Cu (ppm) JJ1 32.32 16.93 JJ2 65.37 13.57 JJ3 48.37 9.65 JJ4 19.92 11.26 JJ5 16.91 14.45 JJ6 24.72 20.42 JJ7 18.40 10.39 JJ8 8.28 5.67 JJ9 25.83 17.98 JJ10 28.11 13.48 JJ11 7.12 5.72 JJ12 54.28 28.31 Avg. BS 22.96 14.55 UCC 44.00 25.00

Zn (ppm) 32.86 135.32 334.17 54.48 29.12 33.94 74.13 29.35 39.51 20.85 28.79 39.40 36.89 71.00

Ga (ppm) 9.13 4.94 5.15 5.38 6.36 9.86 11.59 1.83 6.82 6.13 6.73 13.53 7.86 17.00

Rb (ppm) 29.45 9.89 7.94 7.16 33.07 47.26 57.30 8.80 34.72 30.90 30.47 64.41 38.37 112.00

Sr (ppm) 148.16 431.32 293.26 337.08 26.79 38.58 61.82 55.65 36.12 36.72 24.51 37.65 39.73 350.00

303

Jiulongwan section, Hubei Province Sample Y (ppm) Zr (ppm) JLW40 16.09 104.27 JLW41 4.28 14.32 JLW42 2.61 4.08 JLW43 18.60 47.32 JLW44 25.06 59.95 JLW45 17.57 57.77 JLW46 40.35 58.15 JLW47 41.67 57.09 JLW48 30.72 62.76 JLW49 32.92 53.99 JLW50 25.73 53.28 JLW51 22.23 71.42 JLW52 18.68 98.06 JLW53 48.83 63.16 JLW54 20.43 65.59 JLW55 23.10 94.54 JLW56 12.13 42.98 JLW58 36.44 147.49 JLW59 20.80 101.61 JLW60 20.67 117.30 JLW61 6.70 12.29 JLW62 7.33 11.52 JLW63 6.99 12.20 JLW64 5.90 7.73 JLW65 4.37 6.28 Avg. BS 24.36 66.89 UCC 22.00 190.00

Nb (ppm) 13.23 1.07 0.42 5.93 7.35 7.27 7.12 6.42 6.66 6.54 7.14 8.56 9.04 7.28 7.46 8.57 4.08 13.44 9.69 11.24 1.95 1.53 1.78 1.21 1.01 7.12 12.00

Mo (ppm) 0.14 22.21 13.84 92.51 120.76 83.45 197.36 246.86 119.94 69.12 112.17 90.32 92.10 174.88 162.10 65.38 16.56 76.62 61.73 367.28 10.86 2.08 7.61 0.55 0.25 115.01 1.50

Cd (ppm) 0.17 0.13 0.03 4.12 8.89 4.27 26.07 4.40 23.45 10.28 26.19 6.30 4.59 6.64 6.44 15.10 5.05 16.13 7.10 2.83 0.66 1.00 0.83 0.57 0.83 9.37 0.0098

Sn (ppm) 3.29 0.62 0.38 2.42 3.07 2.72 3.30 2.43 3.63 2.95 2.67 3.17 2.50 2.66 3.09 2.63 1.38 4.13 2.72 3.14 1.09 0.89 0.94 0.71 0.74 2.61 5.50

Jijiawan section, Hubei Province Sample Y (ppm) Zr (ppm) JJ1 12.73 81.11 JJ2 14.67 42.80 JJ3 7.55 32.93 JJ4 6.23 11.13 JJ5 6.08 21.59 JJ6 12.27 31.76 JJ7 11.63 39.64 JJ8 2.56 6.49 JJ9 6.58 20.22 JJ10 13.02 22.74 JJ11 5.06 18.49 JJ12 11.38 42.58 Avg. BS 8.57 25.44 UCC 22.00 190.00

Nb (ppm) 5.88 3.24 2.59 2.41 1.70 2.38 3.53 0.16 0.27 0.25 0.08 2.82 1.40 12.00

Mo (ppm) 0.80 7.29 5.63 0.74 1.42 1.42 1.64 0.78 1.21 2.01 1.37 3.87 1.72 1.50

Cd (ppm) 0.11 0.07 0.09 0.06 0.00 0.03 0.03 0.01 0.03 0.04 0.06 0.26 0.06 0.0098

Sn (ppm) 0.69 0.37 0.45 0.57 0.86 1.05 1.27 0.82 1.51 1.21 0.87 2.01 1.20 5.50

304

Jiulongwan section, Hubei Province Sample Cs (ppm) Ba (ppm) JLW40 14.69 415.58 JLW41 1.43 4289.68 JLW42 0.48 135.22 JLW43 5.51 3158.89 JLW44 13.16 4620.03 JLW45 6.78 1033.65 JLW46 6.20 4782.23 JLW47 5.47 4441.52 JLW48 7.24 4084.43 JLW49 5.88 4651.35 JLW50 5.18 3630.46 JLW51 7.31 773.62 JLW52 5.68 578.26 JLW53 6.74 4565.46 JLW54 7.95 3873.91 JLW55 5.44 4139.89 JLW56 2.63 347.06 JLW58 8.70 1368.16 JLW59 5.75 528.98 JLW60 8.26 470.53 JLW61 3.30 257.38 JLW62 1.82 148.76 JLW63 1.73 282.21 JLW64 0.98 111.29 JLW65 1.03 64.33 Avg. BS 6.09 2709.12 UCC 4.60 550.00

La (ppm) 30.34 6.02 3.44 26.02 33.84 27.42 43.11 44.12 36.12 35.72 22.69 35.73 22.51 47.41 34.05 31.60 16.71 50.55 34.13 29.38 9.97 9.44 8.82 6.90 5.51 30.55 30.00

Ce (ppm) 43.51 9.85 3.61 45.29 60.18 47.18 79.72 77.79 64.96 64.48 40.85 59.97 36.14 89.27 57.10 52.93 30.27 92.30 59.44 51.63 14.66 14.51 13.86 10.50 8.14 53.84 64.00

Pr (ppm) 4.56 1.35 0.62 5.71 7.81 6.08 10.83 9.71 8.34 8.87 6.45 7.64 4.87 12.03 7.42 6.06 3.82 10.72 7.03 5.92 2.12 2.13 2.02 1.62 1.26 6.91 7.10

Nd (ppm) 16.02 5.11 2.19 21.98 29.90 22.34 42.20 37.93 31.97 34.25 30.74 29.01 18.21 48.33 27.12 23.14 14.73 40.99 24.89 21.81 7.64 7.89 7.88 6.06 4.62 26.68 26.00

Jijiawan section, Hubei Province Sample Cs (ppm) Ba (ppm) JJ1 1.81 168.33 JJ2 1.69 444.57 JJ3 1.08 110.67 JJ4 1.25 113.71 JJ5 2.31 459.25 JJ6 2.67 722.08 JJ7 3.41 2609.03 JJ8 0.95 120.74 JJ9 2.13 179.98 JJ10 1.78 164.28 JJ11 1.86 200.41 JJ12 3.98 269.20 Avg. BS 2.39 590.62 UCC 4.60 550.00

La (ppm) 11.44 9.20 4.27 5.12 11.99 16.19 25.35 2.51 11.87 9.37 5.65 19.34 12.78 30.00

Ce (ppm) 18.73 12.40 6.27 7.33 12.30 18.90 27.65 1.88 11.93 10.15 6.72 12.98 12.81 64.00

Pr (ppm) 2.83 2.28 1.14 1.33 2.18 3.69 5.35 0.51 2.02 2.25 1.39 2.19 2.45 7.10

Nd (ppm) 11.46 9.70 4.86 5.37 7.19 14.09 20.32 1.68 6.65 8.86 5.13 7.66 8.95 26.00

305

Jiulongwan section, Hubei Province Sample Sm (ppm) Eu (ppm) JLW40 2.96 0.64 JLW41 1.04 0.75 JLW42 0.41 0.10 JLW43 3.96 1.20 JLW44 5.70 1.64 JLW45 4.35 0.92 JLW46 8.41 2.26 JLW47 7.00 1.99 JLW48 6.23 1.72 JLW49 6.83 1.93 JLW50 5.50 1.51 JLW51 5.63 1.08 JLW52 3.49 0.70 JLW53 9.46 2.46 JLW54 5.21 1.46 JLW55 4.61 1.35 JLW56 2.90 0.58 JLW58 7.49 1.61 JLW59 4.67 0.88 JLW60 4.05 0.77 JLW61 1.45 0.31 JLW62 1.57 0.31 JLW63 1.49 0.32 JLW64 1.14 0.24 JLW65 0.89 0.18 Avg. BS 5.10 1.31 UCC 4.50 0.88

Gd (ppm) 2.69 0.94 0.43 3.72 5.12 3.77 7.76 7.24 5.92 6.61 5.15 4.92 3.25 9.43 4.61 4.31 2.65 7.15 4.20 3.49 1.30 1.49 1.39 1.08 0.83 4.77 3.80

Tb (ppm) 0.38 0.12 0.06 0.50 0.65 0.49 1.05 0.96 0.78 0.86 0.50 0.63 0.41 1.22 0.58 0.56 0.34 0.94 0.54 0.49 0.18 0.20 0.19 0.14 0.11 0.62 0.64

Dy (ppm) 2.76 0.73 0.40 3.42 4.47 3.23 7.12 6.61 5.28 5.70 3.68 4.23 3.02 8.21 3.94 4.01 2.38 6.78 3.84 3.51 1.24 1.25 1.17 1.00 0.72 4.24 3.50

Ho (ppm) 0.59 0.16 0.08 0.69 0.92 0.63 1.38 1.35 1.11 1.14 0.69 0.82 0.63 1.68 0.78 0.88 0.50 1.50 0.80 0.82 0.25 0.26 0.25 0.19 0.15 0.87 0.80

Jijiawan section, Hubei Province Sample Sm (ppm) Eu (ppm) JJ1 2.27 0.54 JJ2 2.03 0.48 JJ3 1.10 0.24 JJ4 1.18 0.26 JJ5 0.99 0.21 JJ6 3.12 0.72 JJ7 2.61 0.76 JJ8 0.36 0.08 JJ9 1.05 0.22 JJ10 1.88 0.50 JJ11 0.85 0.19 JJ12 1.55 0.33 Avg. BS 1.55 0.38 UCC 4.50 0.88

Gd (ppm) 2.29 2.02 1.00 1.14 0.94 3.09 2.09 0.39 1.09 2.17 0.88 1.61 1.53 3.80

Tb (ppm) 0.33 0.29 0.14 0.16 0.13 0.34 0.28 0.05 0.13 0.31 0.12 0.20 0.19 0.64

Dy (ppm) 2.24 2.06 1.06 1.07 0.94 2.22 2.12 0.34 0.96 2.20 0.86 1.62 1.41 3.50

Ho (ppm) 0.46 0.44 0.23 0.23 0.21 0.41 0.45 0.09 0.23 0.47 0.19 0.33 0.30 0.80

306

Jiulongwan section, Hubei Province Sample Er (ppm) Tm (ppm) JLW40 2.02 0.34 JLW41 0.45 0.06 JLW42 0.23 0.03 JLW43 2.02 0.31 JLW44 2.74 0.39 JLW45 2.08 0.31 JLW46 4.17 0.54 JLW47 4.10 0.56 JLW48 3.39 0.48 JLW49 3.35 0.44 JLW50 2.03 0.27 JLW51 2.51 0.38 JLW52 1.97 0.29 JLW53 4.81 0.61 JLW54 2.36 0.36 JLW55 2.54 0.35 JLW56 1.45 0.19 JLW58 4.28 0.66 JLW59 2.37 0.37 JLW60 2.55 0.41 JLW61 0.76 0.11 JLW62 0.78 0.10 JLW63 0.70 0.10 JLW64 0.60 0.08 JLW65 0.42 0.06 Avg. BS 2.60 0.37 UCC 2.30 0.33

Yb (ppm) 2.25 0.41 0.20 1.85 2.28 1.84 3.03 3.06 2.80 2.73 1.23 2.21 1.74 3.54 2.25 2.03 1.10 3.71 2.13 2.58 0.65 0.65 0.56 0.48 0.34 2.14 2.20

Lu (ppm) 0.36 0.06 0.03 0.29 0.34 0.30 0.47 0.47 0.45 0.46 0.22 0.37 0.30 0.53 0.38 0.37 0.18 0.59 0.35 0.44 0.11 0.10 0.09 0.07 0.05 0.35 0.32

Hf (ppm) 2.52 0.26 0.06 1.20 1.58 1.58 1.51 1.58 1.73 1.54 1.08 1.91 2.60 1.65 1.87 2.62 1.24 4.15 2.77 3.20 0.31 0.29 0.28 0.14 0.14 1.80 5.80

Ta (ppm) 1.05 0.11 0.03 0.57 0.67 0.68 0.67 0.62 0.63 0.72 0.46 0.78 0.85 0.65 0.68 0.74 0.37 1.30 0.92 1.09 0.30 0.26 0.18 0.16 0.17 0.66 1.00

Jijiawan section, Hubei Province Sample Er (ppm) Tm (ppm) JJ1 1.33 0.18 JJ2 1.23 0.18 JJ3 0.72 0.11 JJ4 0.68 0.10 JJ5 0.69 0.10 JJ6 1.26 0.17 JJ7 1.50 0.23 JJ8 0.28 0.04 JJ9 0.79 0.12 JJ10 1.50 0.21 JJ11 0.62 0.10 JJ12 1.11 0.18 Avg. BS 0.97 0.14 UCC 2.30 0.33

Yb (ppm) 1.17 1.08 0.60 0.49 0.66 1.09 1.51 0.28 0.84 1.39 0.65 1.24 0.96 2.20

Lu (ppm) 0.20 0.16 0.10 0.08 0.10 0.18 0.25 0.04 0.14 0.22 0.10 0.22 0.15 0.32

Hf (ppm) 1.88 0.92 0.78 0.23 0.56 0.79 1.29 0.10 0.51 0.55 0.50 1.01 0.67 5.80

Ta (ppm) 0.42 0.25 0.23 0.20 0.19 0.29 0.39 0.03 0.08 0.12 0.05 0.31 0.18 1.00

307

Jiulongwan section, Hubei Province Sample W (ppm) Pb (ppm) JLW40 15.66 106.97 JLW41 37.58 8.08 JLW42 30.75 3.38 JLW43 20.64 39.81 JLW44 15.57 44.46 JLW45 18.40 55.43 JLW46 20.91 48.74 JLW47 15.91 30.84 JLW48 13.61 57.34 JLW49 24.50 49.81 JLW50 20.28 34.17 JLW51 18.62 55.73 JLW52 12.06 41.11 JLW53 14.88 57.89 JLW54 19.67 56.01 JLW55 10.70 30.30 JLW56 4.43 14.07 JLW58 17.18 64.33 JLW59 13.01 37.01 JLW60 12.31 52.49 JLW61 47.08 9.18 JLW62 27.12 5.86 JLW63 16.42 10.74 JLW64 16.43 6.48 JLW65 14.17 6.06 Avg. BS 17.95 41.11 UCC 2.00 17.00

Bi (ppm) 0.60 0.09 0.03 0.46 0.59 0.58 0.58 0.47 0.80 0.52 0.45 0.69 0.52 0.48 0.62 0.38 0.21 0.79 0.52 0.63 0.11 0.06 0.09 0.07 0.05 0.50 0.00127

Th (ppm) 21.12 1.79 0.75 10.20 13.18 13.25 12.59 10.56 13.50 13.82 6.02 15.74 11.58 13.42 15.21 11.81 5.54 18.62 13.27 15.59 3.65 2.92 2.83 1.86 1.80 11.39 10.70

U (ppm)

Jijiawan section, Hubei Province Sample W (ppm) Pb (ppm) JJ1 5.70 6.48 JJ2 10.89 2.90 JJ3 12.62 3.28 JJ4 14.16 3.57 JJ5 56.02 16.24 JJ6 62.69 25.65 JJ7 68.93 34.06 JJ8 368.87 5.16 JJ9 286.88 13.19 JJ10 319.03 13.89 JJ11 229.42 6.29 JJ12 89.78 9.43 Avg. BS 185.20 15.49 UCC 2.00 17.00

Bi (ppm) 0.05 0.02 0.01 0.04 0.09 0.11 0.14 0.07 0.12 0.14 0.12 0.14 0.12 0.00127

Th (ppm) 2.50 1.47 1.03 0.89 1.94 3.72 4.11 0.68 2.10 1.86 1.66 3.95 2.50 10.70

U (ppm)

308

Mo/Sc

9.91 9.55 3.23 12.58 16.85 12.49 26.39 26.84 21.31 16.14 5.60 15.20 11.28 31.54 14.74 9.86 6.00 24.06 14.87 21.20 1.44 1.64 2.15 1.07 0.89 15.77 2.80

0.01 4.95 5.26 7.33 7.97 5.45 12.23 17.28 6.89 4.62 1.90 5.75 8.86 11.30 9.38 6.21 3.30 5.03 6.11 28.28 2.22 0.58 1.99 0.23 0.12 8.32 0.11

Mo/Sc 1.25 2.45 0.65 0.89 1.10 1.28 1.83 0.61 1.40 2.03 1.39 2.19 1.48 2.80

0.09 1.67 1.31 0.13 0.20 0.13 0.11 0.16 0.14 0.13 0.19 0.35 0.18 0.11

Jiulongwan section, Hubei Province Sample V/Sc U/Sc JLW40 19.55 0.50 JLW41 37.55 2.13 JLW42 65.08 1.23 JLW43 75.51 1.00 JLW44 91.97 1.11 JLW45 81.15 0.82 JLW46 85.52 1.64 JLW47 101.94 1.88 JLW48 85.71 1.22 JLW49 74.21 1.08 JLW50 27.11 0.09 JLW51 100.49 0.97 JLW52 109.83 1.09 JLW53 80.92 2.04 JLW54 71.25 0.85 JLW55 75.65 0.94 JLW56 84.03 1.20 JLW58 135.26 1.58 JLW59 133.85 1.47 JLW60 185.17 1.63 JLW61 47.80 0.30 JLW62 21.24 0.46 JLW63 27.17 0.56 JLW64 24.52 0.44 JLW65 17.86 0.42 Avg. BS 89.59 1.26 UCC 7.87 0.21 Jijiawan section, Hubei Province Sample V/Sc U/Sc JJ1 6.02 0.14 JJ2 8.91 0.56 JJ3 6.28 0.15 JJ4 9.14 0.16 JJ5 10.08 0.15 JJ6 9.49 0.11 JJ7 7.92 0.12 JJ8 3.17 0.12 JJ9 5.45 0.16 JJ10 3.65 0.13 JJ11 6.16 0.20 JJ12 10.04 0.20 Avg. BS 7.00 0.15 UCC 7.87 0.21

Mo/TOC (10-4)

0.18 1.49 1.91 18.52 20.46 15.22 36.82 41.55 21.79 12.82 25.00 20.15 21.88 40.82 37.93 12.47 3.08 16.64 11.13 181.19 24.41 11.06 120.41 12.11 23.72 28.47

Mo/TOC (10-4)

0.42 1.81 1.59 0.88 0.25 0.43 0.64 1.43 0.57 0.77 5.39 1.58 1.38

309

V/TOC (10-4)

Th/U

493.00 11.26 23.65 190.65 236.04 226.42 257.50 245.10 271.21 206.04 357.55 351.95 271.13 292.25 288.13 151.98 78.39 447.28 243.78 1186.37 524.85 404.05 1640.22 1305.09 3625.97 280.88

V/TOC (10-4)

28.70 9.68 7.68 62.50 12.92 32.07 45.79 28.67 22.54 21.44 170.85 45.11 47.42

V/(V+Ni)

2.13 0.19 0.23 0.81 0.78 1.06 0.48 0.39 0.63 0.86 1.07 1.04 1.03 0.43 1.03 1.20 0.92 0.77 0.89 0.74 2.53 1.78 1.31 1.73 2.01 0.77 3.82

Th/U

0.94 0.94 0.94 0.90 0.90 0.94 0.89 0.88 0.90 0.90 0.91 0.95 0.94 0.94 0.94 0.86 0.92 0.94 0.94 0.96 0.80 0.86 0.85 0.77 0.81 0.92 0.71

V/(V+Ni)

2.00 0.60 1.59 1.00 1.77 2.90 2.24 1.13 1.50 0.92 1.19 1.80 1.68 3.82

0.63 0.37 0.36 0.72 0.81 0.81 0.86 0.65 0.65 0.67 0.86 0.67 0.75 0.71

Wuhe section, Hubei Province Sample Distance (m) Formation WH1 0 Dengying WH5 6 Dengying WH7 10 Dengying WH9 14.5 Dengying WH11 19.5 Dengying WH14 27 Dengying WH17 35 Dengying WH19 42 Dengying Upper Continental Crust

Position: 30°46'51.96"N, 111° 2'15.41"E Lithology Si (%) Al (%) Carbonatic shale Limestone Limestone Silty limestone Limestone Limestone Limestone Limestone

Huanglian section, Guizhou Province Sample Distance (m) Formation HL1 0 DST? HL2 1 DST? HL5 2 Liuchapo HL6 2.5 Liuchapo HL7 3 Liuchapo HL8 3.6 Liuchapo HL9 4.1 Liuchapo HL13 6.5 Liuchapo HL12 8 Liuchapo HL14 9 Liuchapo HL15 10 Liuchapo HL10 12 Jiumenchong HL11 13 Jiumenchong Upper Continental Crust

Position: 28°11'51.19"N, 109°15'43.14"E Lithology Si (%) Al (%) Black shale 10.33 2.46 Black shale 34.24 8.31 Siliceous black shale 40.72 3.63 Siliceous black shale 45.60 0.42 Siliceous black shale 42.01 1.52 Siliceous black shale 42.05 1.51 Siliceous black shale 43.47 1.02 Siliceous black shale 42.06 0.43 Siliceous black shale 43.51 0.15 Siliceous black shale 43.57 0.14 Siliceous black shale 43.79 0.13 Black shale 25.93 4.26 Black shale 25.63 5.38 30.80 8.04

310

Fe (%) 0.35 0.10 0.04 0.08 0.06 0.03 0.06 3.50

Fe (%) 1.20 0.66 0.57 0.14 0.26 0.57 0.65 0.17 0.09 0.10 0.10 0.31 0.62 3.50

Wuhe section, Hubei Province Sample Mg (%) Ca (%) WH1 WH5 WH7 WH9 WH11 WH14 WH17 WH19 UCC Huanglian section, Guizhou Province Sample Mg (%) Ca (%) HL1 9.57 3.32 HL2 0.84 11.22 HL5 0.30 4.91 HL6 0.16 0.56 HL7 0.33 2.05 HL8 0.25 2.03 HL9 0.59 1.37 HL13 0.08 0.58 HL12 0.07 0.20 HL14 0.08 0.19 HL15 0.06 0.18 HL10 0.49 5.75 HL11 0.37 7.26 UCC 1.33 3.00

Na (%)

K (%)

P (%)

TC (%) 3.88 12.43 11.84 10.10 10.35 10.64 10.94 10.80

Na (%)

K (%) 0.00 0.53 0.30 0.01 0.23 0.29 0.21 0.01 0.04 0.00 -0.03 0.37 1.40 2.89

311

P (%) 1.17 4.63 2.22 0.16 0.81 0.72 0.37 0.17 0.04 0.04 0.03 1.84 2.13 2.80

TC (%) 0.06 0.02 0.01 0.00 0.01 0.01 0.04 0.01 0.01 0.01 0.01 0.02 0.03 0.07

9.29 2.99 1.29 1.48 0.96 0.74 1.07 2.36 1.70 1.48 1.33 8.69 8.85

Wuhe section, Hubei Province Sample TS (%) TOC (%) WH1 0.36 WH5 0.12 WH7 0.12 WH9 0.02 WH11 0.05 WH14 0.04 WH17 0.07 WH19 0.08 UCC

0.19 1.73 2.64 0.26 0.43 0.23 0.39 0.42

Huanglian section, Guizhou Province Sample TS (%) TOC (%) HL1 HL2 HL5 HL6 HL7

0.18 0.19 0.04 0.11 0.06

34

Pyrite S (%) 0.18 0.02 0.02 0.01 0.01 0.01 0.01 0.03

δ S pyrite -12.23

Pyrite S (%)

δ S pyrite

1.13 3.10 1.40 1.55 1.01

0.28 0.10 0.01 0.07 0.01

HL8 0.49 0.87 HL9 0.25 0.83 HL13 0.07 2.62 HL12 0.05 1.87 HL14 0.06 1.42 HL15 0.05 1.47 HL10 0.22 9.39 HL11 0.88 9.56 UCC Wuhe section, Hubei Province Sample Sc (ppm) Ti (ppm) WH1 2.51 220.46 WH5 0.26 89.70 WH7 0.07 20.68 WH9 0.11 13.53 WH11 0.07 26.68 WH14 0.00 10.97 WH17 0.00 14.87 WH19 0.21 32.62 UCC 13.60 4100.00

0.32 0.18 0.02 0.00 0.01 0.02 0.00 0.18

V (ppm) 16.59 12.73 9.80 7.28 9.11 5.84 6.78 10.44 107.00

312

34

Li (ppm) 6.69 3.70 1.37 2.04 10.03 1.80 3.30 1.84 20.00

Li (ppm)

Be (ppm) 0.31 0.07 0.06 0.04 0.02 0.00 0.08 0.10 3.00

Be (ppm)

4.26210166

6.28857583

Cr (ppm) 13.03 10.33 8.27 11.46 12.07 9.04 8.58 11.94 83.00

8.91

0.15

20.00

3.00

Mn (ppm) 2096.04 328.68 199.07 181.69 75.86 81.46 115.66 57.85 600.00

Co (ppm) 28.28 4.47 3.36 3.55 4.49 3.93 3.15 3.20 17.00

Huanglian section, Guizhou Province Sample Sc (ppm) Ti (ppm) HL1 3.70 1343.93 HL2 14.20 4828.28 HL5 6.00 1938.04 HL6 0.10 215.55 HL7 2.30 735.71 HL8 3.10 855.20 HL9 3.50 531.29 HL13 0.70 258.44 HL12 0.00 69.95 HL14 0.10 93.57 HL15 0.00 93.83 HL10 12.80 3101.20 HL11 11.00 3844.47 UCC 13.60 4100.00

V (ppm) 74.20 1977.70 97.70 157.10 71.90 107.10 36.00 276.00 186.50 128.00 61.30 9859.50 3654.30 107.00

Cr (ppm) 32.70 183.80 60.10 49.60 44.80 59.60 30.50 71.10 51.30 35.30 23.00 372.50 129.80 83.00

Mn (ppm) 1407.21 46.33 38.65 15.47 37.72 22.71 54.00 29.68 52.73 7.56 22.73 12.84 0.00 600.00

Co (ppm)

Wuhe section, Hubei Province Sample Ni (ppm) Cu (ppm) WH1 4.03 3.59 WH5 9.52 4.96 WH7 4.72 2.14 WH9 3.86 2.64 WH11 5.34 3.46 WH14 3.37 2.38 WH17 2.20 1.99 WH19 4.46 2.49 UCC 44.00 25.00

Zn (ppm) 24.79 74.42 32.86 20.46 18.82 19.90 21.75 18.66 71.00

Ga (ppm) 8.00 1.06 0.45 0.42 0.44 0.37 0.45 0.63 17.00

Rb (ppm) 10.16 2.07 1.44 1.09 0.66 0.26 1.42 0.60 112.00

Sr (ppm) 42.42 777.73 1211.49 1290.62 2218.64 1408.48 2418.88 2102.20 350.00

Huanglian section, Guizhou Province Sample Ni (ppm) Cu (ppm) HL1 19.00 6.80 HL2 27.50 2.90 HL5 6.00 10.00 HL6 15.30 20.70 HL7 3.00 3.40 HL8 12.70 9.60 HL9 8.80 15.50 HL13 15.80 22.90 HL12 12.70 39.50 HL14 12.20 24.80 HL15 11.50 21.00 HL10 241.00 14.60 HL11 148.20 6.80 UCC 44.00 25.00

Zn (ppm) 41.10 7.60 7.60 19.80 3.50 15.70 23.20 22.20 11.30 16.90 16.80 22.80 13.70 71.00

Ga (ppm) 6.80 21.30 9.90 1.40 4.50 4.00 3.70 1.80 0.60 1.00 1.30 16.50 17.40 17.00

Rb (ppm) 40.60 160.00 58.60 4.90 21.80 21.20 14.70 7.50 1.60 1.70 1.10 102.90 101.20 112.00

Sr (ppm) 362.00 21.90 27.30 7.00 13.30 10.30 35.80 6.90 8.60 16.00 13.60 45.40 149.40 350.00

313

286.48

17.00

Wuhe section, Hubei Province Sample Y (ppm) Zr (ppm) WH1 5.69 7.77 WH5 1.58 2.03 WH7 0.99 0.86 WH9 0.35 0.81 WH11 1.15 1.71 WH14 0.77 0.56 WH17 0.83 0.53 WH19 1.30 1.09 UCC 22.00 190.00

Nb (ppm) 0.06 1.62 0.09 0.13 0.16 0.04 0.08 0.13 12.00

Mo (ppm) 0.94 0.18 0.15 0.01 0.05 0.00 0.00 0.10 1.50

Cd (ppm) 0.06 0.04 0.02 0.01 0.00 0.00 0.00 0.00 0.0098

Sn (ppm) 0.94 0.63 0.32 0.38 0.48 0.35 0.27 0.43 5.50

Huanglian section, Guizhou Province Sample Y (ppm) Zr (ppm) HL1 10.90 40.10 HL2 24.20 154.70 HL5 14.70 90.50 HL6 10.70 19.20 HL7 14.30 34.90 HL8 16.10 38.00 HL9 10.10 29.90 HL13 20.00 52.00 HL12 4.70 14.50 HL14 8.80 14.50 HL15 7.80 16.50 HL10 82.10 153.60 HL11 47.50 190.20 UCC 22.00 190.00

Nb (ppm) 4.30 16.90 6.30 1.60 2.90 3.00 2.40 2.10 1.60 1.80 1.70 11.90 14.50 12.00

Mo (ppm) 0.04 58.96 2.97 6.46 0.93 1.92 1.39 1.54 1.98 3.45 2.93 42.20 96.33 1.50

Cd (ppm)

Sn (ppm)

314

0.77

0.61

0.0098

5.50

Wuhe section, Hubei Province Sample Cs (ppm) Ba (ppm) WH1 1.51 100.66 WH5 1.11 34.23 WH7 1.27 31.32 WH9 1.08 11.60 WH11 0.81 18.95 WH14 1.65 7.95 WH17 0.78 10.83 WH19 0.97 10.33 UCC 4.60 550.00

La (ppm) 4.69 1.79 0.96 0.18 0.73 0.63 0.60 1.08 30.00

Ce (ppm) 11.19 1.11 0.00 0.00 0.00 0.00 0.00 0.00 64.00

Pr (ppm) 1.18 0.44 0.22 0.10 0.19 0.16 0.14 0.26 7.10

Nd (ppm) 4.41 1.71 0.79 0.21 0.72 0.50 0.43 1.00 26.00

Huanglian section, Guizhou Province Sample Cs (ppm) Ba (ppm) HL1 766.80 HL2 1611.40 HL5 3519.40 HL6 356.30 HL7 1436.00 HL8 1070.80 HL9 541.90 HL13 293.70 HL12 384.10 HL14 0.57 209.40 HL15 290.20 HL10 8336.20 HL11 13025.80 UCC 4.60 550.00

La (ppm) 13.00 40.30 9.20 0.50 4.50 5.70 2.90 2.90 -0.40 0.70 0.50 29.00 29.30 30.00

Ce (ppm) 24.50 76.90 16.90 0.00 6.70 8.50 7.40 2.70 -1.10 2.50 1.00 43.60 49.00 64.00

Pr (ppm)

Nd (ppm) 12.70 32.00 9.90 4.50 5.80 6.10 6.50 5.10 1.60 4.50 3.20 33.90 27.00 26.00

315

1.10

7.10

Wuhe section, Hubei Province Sample Sm (ppm) Eu (ppm) WH1 0.88 0.22 WH5 0.37 0.08 WH7 0.15 0.04 WH9 0.05 0.02 WH11 0.14 0.04 WH14 0.12 0.03 WH17 0.11 0.03 WH19 0.21 0.06 UCC 4.50 0.88 Huanglian section, Guizhou Province Sample Sm (ppm) Eu (ppm) HL1 HL2 HL5 HL6 HL7 HL8 HL9 HL13 HL12 HL14 1.53 0.52 HL15 HL10 HL11 UCC 4.50 0.88

Gd (ppm) 0.90 0.38 0.18 0.07 0.20 0.11 0.13 0.25 3.80

Tb (ppm) 0.14 0.04 0.02 0.01 0.02 0.02 0.01 0.03 0.64

Dy (ppm) 0.96 0.26 0.15 0.05 0.15 0.11 0.10 0.17 3.50

Ho (ppm) 0.22 0.06 0.03 0.01 0.04 0.02 0.02 0.03 0.80

Gd (ppm)

Tb (ppm)

Dy (ppm)

Ho (ppm)

2.00

0.25

1.67

0.32

3.80

0.64

3.50

0.80

316

Wuhe section, Hubei Province Sample Er (ppm) Tm (ppm) WH1 0.72 0.11 WH5 0.13 0.02 WH7 0.07 0.01 WH9 0.02 0.00 WH11 0.09 0.01 WH14 0.06 0.01 WH17 0.05 0.01 WH19 0.10 0.01 UCC 2.30 0.33 Huanglian section, Guizhou Province Sample Er (ppm) Tm (ppm) HL1 HL2 HL5 HL6 HL7 HL8 HL9 HL13 HL12 HL14 0.88 0.12 HL15 HL10 HL11 UCC 2.30 0.33

Yb (ppm) 0.66 0.10 0.08 0.03 0.07 0.03 0.04 0.08 2.20

Lu (ppm) 0.10 0.01 0.01 0.00 0.01 0.00 0.00 0.01 0.32

Hf (ppm) 0.13 0.01 0.00 0.00 0.00 0.00 0.00 0.00 5.80

Ta (ppm) 0.03 0.16 0.05 0.12 0.19 0.08 0.05 0.07 1.00

Yb (ppm)

Lu (ppm)

Hf (ppm)

Ta (ppm)

0.74

0.12

0.06

0.01

2.20

0.32

5.80

1.00

317

Wuhe section, Hubei Province Sample W (ppm) Pb (ppm) WH1 63.37 8.97 WH5 27.35 2.56 WH7 19.02 1.68 WH9 24.46 1.19 WH11 31.05 1.27 WH14 20.13 4.83 WH17 16.81 0.73 WH19 15.59 0.52 UCC 2.00 17.00 Huanglian section, Guizhou Province Sample W (ppm) Pb (ppm) HL1 5.90 HL2 45.00 HL5 3.60 HL6 0.00 HL7 1.40 HL8 1.20 HL9 0.70 HL13 1.40 HL12 0.00 HL14 684.12 0.00 HL15 0.00 HL10 46.70 HL11 36.90 UCC 2.00 17.00

Bi (ppm) 0.08 0.02 0.01 0.02 0.01 0.01 0.02 0.02 0.00127

Th (ppm) 1.21 0.15 0.01 0.00 0.00 0.00 0.00 0.02 10.70

U (ppm)

Bi (ppm)

Th (ppm) 7.10 15.00 3.30 0.00 0.50 0.70 1.30 0.00 0.00 0.00 0.00 7.00 9.10 10.70

U (ppm)

0.03

0.00127

318

Mo/Sc 2.60 1.46 0.90 0.38 1.46 0.75 0.91 1.60 2.80

0.38 0.68 2.05 0.13 0.80

0.46 0.11

Mo/Sc 0.01 4.15 0.50 64.56 0.40 0.62 0.40 2.20 4.75

34.49

2.80

3.30 8.76 0.11

Wuhe section, Hubei Province Sample V/Sc WH1 6.61 WH5 48.95 WH7 134.49 WH9 68.26 WH11 138.77 WH14 WH17 WH19 50.18 UCC 7.87

Mo/TOC (10-4)

U/Sc

Huanglian section, Guizhou Province Sample V/Sc U/Sc HL1 20.05 HL2 139.27 HL5 16.28 HL6 1571.00 HL7 31.26 HL8 34.55 HL9 10.29 HL13 394.29 HL12 HL14 1280.00 HL15 HL10 770.27 HL11 332.21 UCC 7.87

1.03 5.60 12.38 3.59 22.16

7.68 0.21

4.88 0.10 0.06 0.05 0.12 0.00 0.00 0.23

Mo/TOC (10-4)

0.03 19.02 2.13 4.16 0.91 2.21 1.66 0.59 1.06 2.43 2.00 4.49 10.07

V/TOC (10-4)

Th/U

86.01 7.36 3.72 27.93 20.98 25.57 17.48 24.85

V/TOC (10-4)

65.72 637.97 69.91 101.23 70.97 123.42 43.15 105.22 99.60 90.20 41.79 1049.85 382.12

V/(V+Ni)

0.47 0.10 0.01 0.00 0.00 0.00 0.00 0.01 3.82

Th/U

V/(V+Ni)

0.00

3.82

319

0.80 0.57 0.67 0.65 0.63 0.63 0.76 0.70 0.71

0.80 0.99 0.94 0.91 0.96 0.89 0.80 0.95 0.94 0.91 0.84 0.98 0.96 0.71

Longbizui section, Guizhou Province Sample Distance (m) Formation LBZ-2 0 Liuchapo LBZ-3 1.7 Liuchapo LBZ-4 3 Liuchapo LBZ-5 4 Liuchapo LBZ-6 5.4 Liuchapo LBZ-7 5.7 Liuchapo LBZ-8 5.85 Liuchapo LBZ-9 6.05 Liuchapo LBZ-10 6.1 Liuchapo LBZ-11 6.2 Liuchapo LBZ-12 6.2 Liuchapo LBZ-13 6.65 Liuchapo LBZ-14 7 Liuchapo LBZ-15 11 Liuchapo LBZ-16 17 Liuchapo LBZ-17 27 Liuchapo LBZ-18 36 Liuchapo LBZ-19 43 Liuchapo LBZ-20 51 Jiumenchong LBZ-21 57 Jiumenchong LBZ-22 65 Jiumenchong LBZ-23 72 Jiumenchong LBZ-24 78 Jiumenchong LBZ-25 86 Jiumenchong LBZ-26 92 Jiumenchong Upper Continental Crust

Position: 28°11'51.19"N, 109°15'43.14"E Lithology Si (%) Al (%) Cherty shale 1.28 Cherty shale 1.95 Cherty shale Cherty shale Cherty shale Cherty shale Cherty shale Cherty shale 3.46 Cherty shale Black shale 2.66 Black shale 3.49 Cherty shale Cherty shale 3.56 Cherty shale 2.92 Cherty shale 0.84 Cherty shale Cherty shale 0.17 Cherty shale 1.18 Black shale 0.89 Black shale 4.24 Black shale 7.30 Black shale 4.39 Black shale 3.51 Black shale 5.52 Black shale 5.84 8.04

Jijiawan section, Hubei Province Sample Distance (m) Formation JJL2 0 Shuijingtuo JJL1 1.7 Shuijingtuo JJL1a 1.85 Shuijingtuo JJL1b 2.45 Shuijingtuo JJL3 3 Shuijingtuo JJL5 6.7 Shuijingtuo JJL6 9.2 Shuijingtuo JJL7 11.2 Shuijingtuo JJL8 16.2 Shuijingtuo JJL9 18.2 Shuijingtuo JJL10 18.7 Shuijingtuo JJL11 20.7 Shuijingtuo

Position: 30°53'0.93"N, 110°52'47.25"E Lithology Si (%) Al (%) Sandy dolomite Carbonate Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Sandy carbonate

Average BS:

Upper Continental Crust

320

Fe (%) 0.44 0.33 0.34 0.56 1.09 1.22 0.83 0.90 0.47 1.51 1.95 0.71 0.77 0.97 0.18 0.54 0.10 0.37 0.53 1.74 3.16 2.36 1.85 3.59 2.62 3.50

Fe (%) 0.37 2.28 1.61 0.32 3.51 2.95 2.51 3.49 2.51 2.45 2.25 0.66 2.40 3.50

Longbizui section, Guizhou Province Sample Mg (%) Ca (%) LBZ-2 0.10 0.02 LBZ-3 0.21 0.04 LBZ-4 LBZ-5 LBZ-6 LBZ-7 LBZ-8 LBZ-9 0.32 0.04 LBZ-10 LBZ-11 0.32 0.03 LBZ-12 0.45 0.04 LBZ-13 LBZ-14 2.29 3.50 LBZ-15 0.28 0.03 LBZ-16 3.12 5.37 LBZ-17 LBZ-18 0.20 1.08 LBZ-19 0.31 1.23 LBZ-20 0.46 0.70 LBZ-21 1.17 5.90 LBZ-22 0.93 1.68 LBZ-23 0.54 1.00 LBZ-24 0.63 1.17 LBZ-25 0.32 0.15 LBZ-26 0.34 0.06 UCC 1.33 3.00 Jijiawan section, Hubei Province Sample Mg (%) Ca (%) JJL2 JJL1 JJL1a JJL1b JJL3 JJL5 JJL6 JJL7 JJL8 JJL9 JJL10 JJL11 Avg. BS UCC

Na (%)

K (%)

P (%)

TC (%)

0.40 0.43

1.91 0.81 0.91 0.30 0.43 0.41 0.76 0.42 0.72 1.17 3.12 0.11 0.75 0.20 2.45 2.61 2.16 0.57 3.79 10.33 8.12 7.36 7.22 5.58 4.89

0.70 0.05 0.06 0.70 0.17 0.05 0.02 0.26 0.11 1.05 1.55 1.14 0.58 1.27 1.06 2.89

Na (%)

K (%)

P (%)

TC (%) 10.24 10.41 5.16 5.50 7.04 6.04 6.73 8.25 6.40 6.51 5.64 9.78 6.36

321

Longbizui section, Guizhou Province Sample TS (%) TOC (%) LBZ-2 0.55 LBZ-3 0.27 LBZ-4 0.41 LBZ-5 0.38 LBZ-6 1.43 LBZ-7 1.62 LBZ-8 0.84 LBZ-9 1.08 LBZ-10 0.64 LBZ-11 0.95 LBZ-12 3.13 LBZ-13 0.05 LBZ-14 0.87 LBZ-15 0.77 LBZ-16 0.21 LBZ-17 0.50 LBZ-18 0.29 LBZ-19 0.48 LBZ-20 1.09 LBZ-21 3.59 LBZ-22 5.47 LBZ-23 4.22 LBZ-24 3.01 LBZ-25 5.79 LBZ-26 3.83 UCC Jijiawan section, Hubei Province Sample TS (%) TOC (%) JJL2 0.16 JJL1 0.29 JJL1a 2.79 JJL1b 2.04 JJL3 5.13 JJL5 3.60 JJL6 3.28 JJL7 4.15 JJL8 3.02 JJL9 2.95 JJL10 2.59 JJL11 0.01 Avg. BS 3.28 UCC

34

1.93 0.81 0.91 0.31 0.40 0.43 0.69 0.44 0.72 1.16 3.12 0.13 0.27 0.23 1.62 0.64 1.78 0.42 3.50 8.36 7.74 6.89 7.09 5.52 4.80

Pyrite S (%) 0.38 0.17 0.24 0.25 0.96 0.86 0.45 0.67 0.39 0.40 1.77 0.03 0.35 0.41 0.07 0.30 0.06 0.20 0.27 1.33 3.00 1.25 1.49 3.32 2.05

δ S pyrite 66.63

δ S pyrite

0.40 0.50 2.36 2.51 5.84 4.25 5.25 4.59 5.13 5.60 5.11 0.16 4.51

Pyrite S (%) 0.25 0.31 1.62 0.95 2.29 2.52 2.22 3.01 1.96 1.98 1.52 0.01 2.01

322

19.72 20.31 12.89 -0.38 15.61 2.25 11.60 15.11 11.90 14.97 18.33

Li (ppm) 10.88 12.78

Be (ppm)

26.57 70.12 40.80 57.72 29.39 12.10

28.79 29.58 13.74 9.34 19.70 26.31 20.65

34

18.55

4.24 2.22 25.27 19.76 16.38 12.29 12.16 21.05 19.15 20.00

Li (ppm) 4.17 4.36 30.64 19.86 22.04 17.78 20.39 18.75 20.64 21.33 20.06 7.97 21.28 20.00

Be (ppm) 0.15 0.17 1.45 0.74 1.70 1.52 1.64 1.49 1.70 1.79 1.57 0.25 1.51 3.00

Longbizui section, Guizhou Province Sample Sc (ppm) Ti (ppm) LBZ-2 2.20 531.87 LBZ-3 3.43 821.15 LBZ-4 LBZ-5 LBZ-6 LBZ-7 LBZ-8 LBZ-9 5.11 1186.70 LBZ-10 LBZ-11 6.85 1584.43 LBZ-12 8.71 2312.89 LBZ-13 LBZ-14 14.50 1297.24 LBZ-15 6.02 1551.35 LBZ-16 2.64 353.50 LBZ-17 LBZ-18 0.27 69.12 LBZ-19 3.65 333.09 LBZ-20 1.29 466.47 LBZ-21 8.48 2339.50 LBZ-22 9.90 2866.33 LBZ-23 7.42 2858.74 LBZ-24 6.89 2408.85 LBZ-25 9.58 2762.87 LBZ-26 6.80 2778.32 UCC 13.60 4100.00 Jijiawan section, Hubei Province Sample Sc (ppm) Ti (ppm) JJL2 1.13 282.44 JJL1 1.03 294.75 JJL1a 8.64 2484.79 JJL1b 5.62 1654.30 JJL3 12.23 2137.92 JJL5 9.06 1613.11 JJL6 9.43 2887.23 JJL7 7.51 2003.15 JJL8 9.28 2754.46 JJL9 9.05 2793.30 JJL10 8.51 2503.67 JJL11 2.24 650.25 Avg. BS 8.81 2314.66 UCC 13.60 4100.00

V (ppm) 19.61 26.79

Cr (ppm) 11.37 16.76

Mn (ppm) 115.89 11.76

33.76

18.74

97.21

171.69 338.84

84.00 180.19

7.76 8.29

55.95 54.80 239.16

33.52 31.02 67.62

221.05 18.45 44.65

542.70 111.86 1936.81 1018.47 364.20 181.82 338.18 643.65 909.13 107.00

147.49 31.84 441.74 115.48 51.14 47.30 40.37 51.75 67.43 83.00

9.43 45.21 17.69 67.46 168.92 180.70 171.81 96.32 130.47 600.00

V (ppm) 12.26 13.29 64.04 36.60 909.93 157.84 154.03 88.72 153.05 219.62 242.51 22.01 225.15 107.00

Cr (ppm) 14.73 15.60 72.46 72.47 76.31 50.96 54.43 51.24 127.98 59.07 82.72 20.02 71.96 83.00

Mn (ppm) 94.40 55.20 77.16 74.31 150.80 219.66 235.93 758.53 201.71 195.38 149.95 238.07 229.27 600.00

323

Co (ppm)

Co (ppm) 5.09 3.85 9.53 8.55 21.83 15.66 15.79 11.75 13.87 13.45 18.37 8.32 14.31 17.00

Longbizui section, Guizhou Province Sample Ni (ppm) Cu (ppm) LBZ-2 5.02 3.68 LBZ-3 3.67 3.08 LBZ-4 LBZ-5 LBZ-6 LBZ-7 LBZ-8 LBZ-9 14.96 11.20 LBZ-10 LBZ-11 3.14 7.08 LBZ-12 7.67 14.78 LBZ-13 LBZ-14 18.66 13.27 LBZ-15 6.17 24.21 LBZ-16 14.83 21.90 LBZ-17 LBZ-18 34.53 33.96 LBZ-19 9.15 127.74 LBZ-20 115.55 74.60 LBZ-21 202.11 102.62 LBZ-22 60.55 63.53 LBZ-23 53.66 43.78 LBZ-24 79.25 39.19 LBZ-25 70.56 84.87 LBZ-26 35.96 35.09 UCC 44.00 25.00 Jijiawan section, Hubei Province Sample Ni (ppm) Cu (ppm) JJL2 44.56 2.33 JJL1 5.48 2.06 JJL1a 35.08 12.87 JJL1b 52.06 7.78 JJL3 245.07 21.28 JJL5 77.44 15.23 JJL6 81.17 16.02 JJL7 72.92 14.11 JJL8 152.43 16.74 JJL9 110.81 15.88 JJL10 111.79 13.84 JJL11 18.79 3.07 Avg. BS 104.31 14.86 UCC 44.00 25.00

Zn (ppm) 3.09 5.67

Rb (ppm) 15.16 28.16

Sr (ppm) 11.23 13.84

9.32

59.30

21.68

3.19 4.45

46.42 61.37

15.20 10.53

32.30 8.31 34.39

56.08 39.44 16.85

100.69 15.65 127.35

735.67 134.93 506.88 1059.10 74.32 77.12 83.57 63.17 7.21 71.00

4.46 19.89 17.75 45.81 75.62 54.66 45.93 80.80 54.04 112.00

87.53 114.37 101.18 338.71 165.35 157.22 124.51 50.81 28.51 350.00

Rb (ppm) 9.03 8.29 79.26 42.42 86.57 70.28 68.64 48.72 68.13 68.23 64.14 13.61 66.27 112.00

Sr (ppm) 268.20 302.42 147.68 167.18 156.83 199.62 232.91 331.99 180.81 164.99 138.68 2832.27 191.19 350.00

Zn (ppm) 49.09 46.64 63.73 211.07 119.58 36.47 37.94 29.12 612.70 31.79 272.78 32.99 157.24 71.00

324

Ga (ppm)

Ga (ppm) 1.37 1.26 11.95 6.56 16.18 12.11 12.38 9.31 12.62 12.63 11.79 2.44 11.73 17.00

Longbizui section, Guizhou Province Sample Y (ppm) Zr (ppm) LBZ-2 2.66 18.70 LBZ-3 5.50 27.61 LBZ-4 LBZ-5 LBZ-6 LBZ-7 LBZ-8 LBZ-9 15.77 57.43 LBZ-10 LBZ-11 12.68 56.06 LBZ-12 31.13 89.82 LBZ-13 LBZ-14 33.20 61.73 LBZ-15 11.79 50.19 LBZ-16 39.68 34.85 LBZ-17 LBZ-18 6.81 4.38 LBZ-19 46.67 16.99 LBZ-20 13.49 18.04 LBZ-21 103.74 101.19 LBZ-22 82.22 132.39 LBZ-23 49.65 87.71 LBZ-24 58.01 69.28 LBZ-25 42.28 92.62 LBZ-26 96.75 UCC 22.00 190.00 Jijiawan section, Hubei Province Sample Y (ppm) Zr (ppm) JJL2 7.85 5.12 JJL1 7.93 5.73 JJL1a 38.54 38.38 JJL1b 25.35 76.20 JJL3 23.87 53.01 JJL5 16.68 47.40 JJL6 17.78 125.28 JJL7 42.55 85.57 JJL8 18.13 119.51 JJL9 15.80 104.04 JJL10 15.84 112.62 JJL11 6.75 27.83 Avg. BS 23.84 84.67 UCC 22.00 190.00

Nb (ppm)

Nb (ppm) 0.93 0.92 7.29 5.77 5.14 3.88 7.85 5.41 7.37 7.14 7.00 1.83 6.32 12.00

325

Mo (ppm) 0.72 0.12

Cd (ppm) 0.02 0.03

1.52

0.08

0.95 2.44

0.08 0.13

0.86 1.84 2.47

0.72 0.10 0.36

5.70 2.48 24.59 65.37 106.71 92.58 106.95 87.50 36.61 1.50

41.38 3.37 30.82 21.00 3.34 2.44 2.69 1.44 0.27 0.0098

Mo (ppm) 0.54 0.67 4.07 6.74 212.83 36.85 40.36 30.79 45.65 43.87 38.48 1.50 51.07 1.50

Cd (ppm) 0.07 0.01 0.14 0.11 0.46 0.24 0.31 0.30 0.30 0.32 0.64 0.07 0.31 0.0098

Sn (ppm)

Sn (ppm) 0.44 0.32 1.60 0.79 2.44 1.47 1.58 1.13 1.63 1.55 1.43 0.37 1.51 5.50

Longbizui section, Guizhou Province Sample Cs (ppm) Ba (ppm) LBZ-2 387.00 LBZ-3 503.74 LBZ-4 LBZ-5 LBZ-6 LBZ-7 LBZ-8 LBZ-9 1279.89 LBZ-10 LBZ-11 2438.17 LBZ-12 89.66 LBZ-13 LBZ-14 1315.64 LBZ-15 809.38 LBZ-16 467.74 LBZ-17 LBZ-18 392.34 LBZ-19 2269.18 LBZ-20 1982.00 LBZ-21 209.11 LBZ-22 79.84 LBZ-23 107.44 LBZ-24 65.24 LBZ-25 31.09 LBZ-26 179.68 UCC 550.00 Jijiawan section, Hubei Province Sample Cs (ppm) Ba (ppm) JJL2 1.41 139.20 JJL1 1.49 141.81 JJL1a 4.25 634.61 JJL1b 2.23 391.51 JJL3 5.07 4723.87 JJL5 3.89 792.67 JJL6 3.65 732.89 JJL7 2.95 630.95 JJL8 3.61 597.77 JJL9 3.70 692.33 JJL10 3.56 1139.85 JJL11 1.14 631.25 Avg. BS 3.66 1148.50 UCC 4.60 550.00

La (ppm)

Ce (ppm) 4.87 9.26

Pr (ppm)

Nd (ppm) 2.28 5.66

34.65

20.96

21.70 46.97

12.84 32.40

34.69 11.49 7.26

23.12 7.84 7.79

30.00

2.22 19.00 11.60 23.54 39.79 28.83 32.57 27.29 30.20 64.00

7.10

2.83 11.00 9.55 25.49 29.61 17.11 18.84 16.24 17.76 26.00

La (ppm) 11.02 10.02 38.28 25.45 19.59 17.80 21.09 30.40 20.81 18.10 20.30 7.21 23.54 30.00

Ce (ppm) 8.90 7.87 35.71 25.18 27.86 31.38 35.60 51.17 33.34 30.98 34.51 12.28 33.97 64.00

Pr (ppm) 2.02 1.81 8.56 5.98 4.31 3.94 4.64 6.79 4.20 3.78 4.26 1.72 5.16 7.10

Nd (ppm) 8.19 7.79 35.48 25.36 19.70 16.15 18.18 28.33 16.41 14.25 15.86 6.35 21.08 26.00

326

Longbizui section, Guizhou Province Sample Sm (ppm) Eu (ppm) LBZ-2 LBZ-3 LBZ-4 LBZ-5 LBZ-6 LBZ-7 LBZ-8 LBZ-9 LBZ-10 LBZ-11 LBZ-12 LBZ-13 LBZ-14 LBZ-15 LBZ-16 LBZ-17 LBZ-18 LBZ-19 LBZ-20 LBZ-21 LBZ-22 LBZ-23 LBZ-24 LBZ-25 LBZ-26 UCC Jijiawan section, Hubei Province Sample Sm (ppm) Eu (ppm) JJL2 1.36 0.30 JJL1 1.35 0.30 JJL1a 7.07 1.42 JJL1b 4.80 1.08 JJL3 3.80 1.45 JJL5 2.80 0.71 JJL6 3.43 0.74 JJL7 5.52 1.34 JJL8 3.13 0.80 JJL9 2.49 0.55 JJL10 3.11 0.79 JJL11 1.24 0.35 Avg. BS 4.02 0.99 UCC 4.50 0.88

Gd (ppm)

Tb (ppm)

Dy (ppm)

Ho (ppm)

Gd (ppm) 1.33 1.26 6.85 4.70 3.96 2.71 3.06 6.14 3.05 2.51 2.94 1.29 3.99 3.80

Tb (ppm) 0.16 0.15 0.82 0.55 0.59 0.38 0.44 0.77 0.41 0.33 0.39 0.17 0.52 0.64

Dy (ppm) 1.03 1.02 5.57 3.57 3.76 2.57 2.99 5.39 2.76 2.38 2.84 1.19 3.54 3.50

Ho (ppm) 0.20 0.20 1.01 0.74 0.79 0.54 0.62 1.13 0.58 0.51 0.57 0.24 0.72 0.80

327

Longbizui section, Guizhou Province Sample Er (ppm) Tm (ppm) LBZ-2 LBZ-3 LBZ-4 LBZ-5 LBZ-6 LBZ-7 LBZ-8 LBZ-9 LBZ-10 LBZ-11 LBZ-12 LBZ-13 LBZ-14 LBZ-15 LBZ-16 LBZ-17 LBZ-18 LBZ-19 LBZ-20 LBZ-21 LBZ-22 LBZ-23 LBZ-24 LBZ-25 LBZ-26 UCC Jijiawan section, Hubei Province Sample Er (ppm) Tm (ppm) JJL2 0.53 0.08 JJL1 0.56 0.07 JJL1a 2.84 0.35 JJL1b 2.05 0.24 JJL3 2.32 0.33 JJL5 1.73 0.24 JJL6 1.96 0.28 JJL7 3.34 0.46 JJL8 1.80 0.27 JJL9 1.67 0.23 JJL10 1.79 0.25 JJL11 0.67 0.09 Avg. BS 2.17 0.29 UCC 2.30 0.33

Yb (ppm)

Lu (ppm)

Hf (ppm)

Ta (ppm)

Yb (ppm) 0.40 0.33 1.83 1.31 1.92 1.50 1.75 2.58 1.59 1.55 1.58 0.57 1.73 2.20

Lu (ppm) 0.06 0.05 0.27 0.18 0.30 0.22 0.28 0.41 0.27 0.26 0.25 0.08 0.27 0.32

Hf (ppm) 0.07 0.10 1.01 1.72 1.38 1.16 2.96 2.02 2.76 2.75 2.80 0.62 2.06 5.80

Ta (ppm) 0.12 0.14 0.39 0.55 0.36 0.28 0.66 0.47 0.59 0.65 0.64 0.21 0.51 1.00

328

Longbizui section, Guizhou Province Sample W (ppm) Pb (ppm) LBZ-2 696.05 2.80 LBZ-3 0.37 1.53 LBZ-4 LBZ-5 LBZ-6 LBZ-7 LBZ-8 LBZ-9 0.74 9.66 LBZ-10 LBZ-11 347.41 38.16 LBZ-12 238.68 84.31 LBZ-13 LBZ-14 0.62 19.81 LBZ-15 430.71 77.29 LBZ-16 0.29 2.11 LBZ-17 LBZ-18 0.07 2.35 LBZ-19 0.40 6.15 LBZ-20 0.29 10.21 LBZ-21 1.11 15.34 LBZ-22 2.05 18.45 LBZ-23 1.71 9.48 LBZ-24 2.04 7.66 LBZ-25 1.96 16.14 LBZ-26 1.62 12.07 UCC 2.00 17.00 Jijiawan section, Hubei Province Sample W (ppm) Pb (ppm) JJL2 30.71 4.08 JJL1 13.27 1.90 JJL1a 35.37 12.91 JJL1b 53.19 6.70 JJL3 17.17 12.54 JJL5 43.61 8.90 JJL6 50.58 9.85 JJL7 31.09 8.69 JJL8 29.76 10.36 JJL9 41.81 9.49 JJL10 57.35 10.14 JJL11 30.54 3.35 Avg. BS 39.99 9.96 UCC 2.00 17.00

Bi (ppm)

Th (ppm) 1.20 1.56

Bi (ppm) 0.02 0.01 0.08 0.04 0.28 0.12 0.12 0.09 0.12 0.13 0.13 0.03 0.12 0.00127

329

U (ppm)

Mo/Sc 0.18 0.40

0.33 0.04

3.98

0.85

0.30

4.22 6.63

1.80 4.33

0.14 0.28

5.73 3.03 1.50

1.43 1.26 3.29

0.06 0.31 0.94

0.26 2.09 1.71 3.85 7.77 4.88 4.77 5.77 6.43 10.70

1.92 2.66 6.42 26.27 44.38 39.75 51.64 27.42 9.11 2.80

20.75 0.68 19.06 7.71 10.78 12.47 15.53 9.13 5.39 0.11

Th (ppm) 0.58 0.60 7.00 3.80 6.73 5.94 6.26 4.31 6.06 6.22 5.67 1.50 5.78 10.70

U (ppm) 1.05 0.99 17.63 8.82 47.23 32.86 34.56 53.19 28.55 28.97 26.18 1.09 30.89 2.80

Mo/Sc 0.48 0.65 0.47 1.20 17.40 4.07 4.28 4.10 4.92 4.85 4.52 0.67 5.09 0.11

Longbizui section, Guizhou Province Sample V/Sc U/Sc LBZ-2 8.93 0.08 LBZ-3 7.80 0.12 LBZ-4 LBZ-5 LBZ-6 LBZ-7 LBZ-8 LBZ-9 6.61 0.17 LBZ-10 LBZ-11 25.05 0.26 LBZ-12 38.88 0.50 LBZ-13 LBZ-14 3.86 0.10 LBZ-15 9.11 0.21 LBZ-16 90.62 1.25 LBZ-17 LBZ-18 1973.90 6.97 LBZ-19 30.62 0.73 LBZ-20 1501.14 4.98 LBZ-21 120.12 3.10 LBZ-22 36.80 4.48 LBZ-23 24.49 5.35 LBZ-24 49.10 7.50 LBZ-25 67.17 2.86 LBZ-26 133.74 1.34 UCC 7.87 0.21 Jijiawan section, Hubei Province Sample V/Sc U/Sc JJL2 10.86 0.93 JJL1 12.87 0.95 JJL1a 7.41 2.04 JJL1b 6.51 1.57 JJL3 74.39 3.86 JJL5 17.43 3.63 JJL6 16.33 3.66 JJL7 11.81 7.08 JJL8 16.49 3.08 JJL9 24.28 3.20 JJL10 28.51 3.08 JJL11 9.84 0.49 Avg. BS 22.57 3.47 UCC 7.87 0.21

Mo/TOC (10-4)

V/TOC (10-4)

Th/U

V/(V+Ni)

0.37 0.15

10.15 32.89

6.54 3.91

0.80 0.88

3.45

76.48

4.67

0.69

0.82 0.78

147.50 108.64

2.34 1.53

0.98 0.98

3.21 8.16 1.52

208.21 243.43 147.27

4.02 2.41 0.46

0.75 0.90 0.94

3.20 5.93 7.03 7.82 13.79 13.44 15.08 15.84 7.63

304.37 266.90 553.37 121.87 47.07 26.39 47.67 116.52 189.48

0.13 0.79 0.27 0.15 0.17 0.12 0.09 0.21 0.71 3.82

0.94 0.92 0.94 0.83 0.86 0.77 0.81 0.90 0.96 0.71

Mo/TOC (10-4)

1.36 1.34 1.73 2.68 36.44 8.68 7.68 6.71 8.90 7.84 7.53 9.63 9.80

330

V/TOC (10-4)

30.90 26.59 27.20 14.57 155.81 37.17 29.32 19.34 29.85 39.23 47.45 141.21 44.44

Th/U

V/(V+Ni)

0.55 0.60 0.40 0.43 0.14 0.18 0.18 0.08 0.21 0.21 0.22 1.37 0.23 3.82

0.22 0.71 0.65 0.41 0.79 0.67 0.65 0.55 0.50 0.66 0.68 0.54 0.62 0.71

Wuhe section, Hubei Province Sample Distance (m) Formation YS107 22.5 Yangjiahe YS108 26 Yangjiahe YS113 41 Yangjiahe YS114 45 Yangjiahe YS115 48 Yangjiahe YS0c 50 Shuijingtuo YS1 51 Shuijingtuo YS2 54 Shuijingtuo YS3 55 Shuijingtuo

Position: 30°46'51.96"N, 111° 2'15.41"E Lithology Si (%) Al (%) Siliceous carbonate Carbonatic shale Black limestone Black sandy limestone Black sandy limestone Black carbonate Black carbonate Black carbonate Black carbonate

Fe (%) 0.38 0.83 0.54 0.52 0.53 0.36 0.60 3.52 2.59

Average BS: Upper Continental Crust Zhongnan section, Guizhou Province Sample Distance (m) Formation ZN0A 0 Niutitang ZN0B 0.05 Niutitang ZN0C 0.15 Niutitang ZN1 0.25 Niutitang ZN2 0.3 Niutitang ZN3 0.35 Niutitang ZN4 0.4 Niutitang ZN5 0.45 Niutitang ZN6 0.55 Niutitang ZN7 0.6 Niutitang ZN8 0.8 Niutitang ZN9 1.2 Niutitang ZN10 1.5 Niutitang ZN11 1.85 Niutitang ZN12 2.45 Niutitang ZN13 3 Niutitang ZN14 3.35 Niutitang Upper Continental Crust

1.77 3.50 Position: 27°41'24.67"N / 106°40'47.38"E Lithology Si (%) Al (%) Phosphorite 8.56 0.34 Phosphorite 4.67 0.70 Phosphorite 5.85 0.65 Phosphorite 5.82 0.42 Phosphorite 6.20 0.73 Phosphorite 8.20 2.34 Ni-Mo Ore horizon 14.45 5.60 Pyrite layer 18.33 7.23 Pyrite layer 14.87 6.24 Black shale 19.93 8.49 Black shale 21.98 11.22 Black shale 29.15 4.04 Black shale 30.03 0.84 Black shale 23.99 4.27 Black shale 27.22 5.57 Black shale 27.55 5.78 Black shale 26.58 5.97 30.80 8.04

331

Fe (%) 0.75 1.10 1.71 0.41 2.10 1.74 12.96 9.73 16.14 1.17 1.77 0.50 0.60 1.07 0.91 0.72 0.49 3.50

Wuhe section, Hubei Province Sample Mg (%) Ca (%) YS107 YS108 YS113 YS114 YS115 YS0c YS1 YS2 YS3

Na (%)

K (%)

P (%)

TC (%) 0.38 1.04 8.58 9.18 8.34 1.95 8.94 5.66 7.14

Avg. BS UCC Zhongnan section, Guizhou Province Sample Mg (%) Ca (%) ZN0A 0.12 0.46 ZN0B 0.22 0.95 ZN0C 0.18 0.88 ZN1 0.20 0.57 ZN2 0.22 0.99 ZN3 0.76 3.16 ZN4 1.53 7.56 ZN5 1.89 9.77 ZN6 2.06 8.42 ZN7 1.63 11.46 ZN8 1.66 15.15 ZN9 0.54 5.45 ZN10 0.09 1.13 ZN11 0.46 5.76 ZN12 0.54 7.52 ZN13 0.58 7.81 ZN14 0.60 8.06 UCC 1.33 3.00

5.92

Na (%)

K (%) 0.03 0.01 -0.04 0.09 0.11 0.08 0.07 0.03 0.04 0.05 0.07 0.03 0.01 0.07 0.56 0.28 0.34 2.89

332

P (%) 0.14 0.34 0.30 0.16 0.27 1.12 2.73 3.37 3.02 3.68 4.79 1.95 0.34 1.93 2.27 2.61 2.69 2.80

TC (%) 13.82 14.96 14.31 14.69 13.63 11.75 2.43 0.94 0.15 0.51 0.31 0.21 1.64 1.16 0.10 0.05 0.03 0.07

0.85 0.71 1.14 0.53 0.44 0.66 0.11 0.13 0.15 10.63 1.97 9.25 9.75 11.29 7.99 7.32 8.68

Wuhe section, Hubei Province Sample TS (%) TOC (%) YS107 0.01 YS108 0.13 YS113 0.39 YS114 0.23 YS115 0.45 YS0c 0.29 YS1 0.50 YS2 4.39 YS3 2.91

0.10 0.29 0.34 0.67 0.43 2.29 0.67 3.41 1.08

Pyrite S (%) 0.08 0.07 0.21 0.18 0.35 0.17 0.36 1.36 0.65

1.86

0.64

Zhongnan section, Guizhou Province Sample TS (%) TOC (%) ZN0A 0.06 0.77 ZN0B 0.07 0.65 ZN0C 0.12 1.07 ZN1 0.13 0.47 ZN2 0.40 0.46 ZN3 1.52 0.64 ZN4 4.64 0.16 ZN5 10.00 0.17 ZN6 18.00 0.18 ZN7 0.19 9.65 ZN8 0.12 1.88 ZN9 0.10 8.97 ZN10 0.15 9.51 ZN11 0.14 11.08 ZN12 0.10 8.02 ZN13 0.08 7.04 ZN14 0.07 8.61 UCC

Pyrite S (%) 0.02 0.02 0.07 0.02 0.02 0.99 2.25 9.36 18.09 0.02 0.03 0.02 0.04 0.02 0.02 0.01 0.01

Avg. BS UCC

2.02

34

δ S pyrite 8.62 2.72 23.12 20.38 17.48 -2.88 -4.93 0.13 2.45

34

δ S pyrite

4.04 11.10 9.53 8.88

Li (ppm) 19.71 38.62 10.27

Be (ppm) 0.21 0.76 0.45

8.36 12.28 6.66 25.17 22.56

0.19 0.35 0.43 1.62 1.34

16.67 20.00

0.93 3.00

Li (ppm)

461.99

20.00

333

Be (ppm)

10.67

3.00

Wuhe section, Hubei Province Sample Sc (ppm) Ti (ppm) YS107 2.31 256.45 YS108 5.79 916.20 YS113 5.37 424.06 YS114 YS115 1.92 387.71 YS0c 1.90 137.11 YS1 2.32 445.38 YS2 11.67 1674.83 YS3 8.75 1506.16

V (ppm) 27.81 96.19 25.70

Cr (ppm) 31.38 82.96 33.43

Mn (ppm) 48.25 67.33 252.69

Co (ppm) 97.49 48.58 8.37

16.06 262.75 28.20 162.95 110.02

19.26 57.90 15.82 59.06 46.76

83.46 58.78 299.09 370.93 413.23

8.54 7.82 6.47 17.10 16.53

940.87 4100.00

140.98 107.00

44.88 83.00

285.51 600.00

11.98 17.00

Zhongnan section, Guizhou Province Sample Sc (ppm) Ti (ppm) ZN0A 0.00 275.67 ZN0B 243.85 ZN0C 2.90 205.87 ZN1 0.00 128.69 ZN2 2.70 216.07 ZN3 4.60 769.56 2171.66 ZN4 8.50 ZN5 10.20 2850.27 ZN6 11.50 3113.48 ZN7 14.70 3692.32 ZN8 3.10 1224.33 ZN9 9.80 2184.48 ZN10 2.80 383.69 ZN11 11.10 2397.02 ZN12 13.30 3528.35 ZN13 14.40 4082.42 ZN14 15.50 4146.42 UCC 13.60 4100.00

V (ppm) 167.40 1088.20 2094.70 765.70 799.90 937.20 294.80 251.90 113.40 2114.20 3069.20 1485.10 487.30 6069.70 2899.10 6732.20 6301.40 107.00

Cr (ppm) 102.50 1116.30 429.50 367.00 445.40 347.70 102.40 109.20 124.20 1240.60 194.30 1242.80 278.70 2428.60 1768.10 1074.80 243.60 83.00

Mn (ppm) 37.89 7.50 22.17 257.00 -7.35 21.94 4986.41 86.42 83.41 0.00 13.70 13.31 13.40 -12.77 0.00 20.21 26.52 600.00

Avg. BS UCC

6.16 13.60

334

Co (ppm)

236.37

17.00

Wuhe section, Hubei Province Sample Ni (ppm) Cu (ppm) YS107 1.45 1.63 YS108 8.27 3.43 YS113 16.88 3.95 YS114 YS115 5.99 2.25 YS0c 10.59 3.50 YS1 59.92 9.86 YS2 84.63 23.00 YS3 84.82 14.78

Zn (ppm) 17.94 23.38 56.13

Ga (ppm) 2.91 6.71 4.11

Rb (ppm) 9.81 28.75 10.96

Sr (ppm) 33.69 32.89 141.75

48.22 25.48 82.57 149.40 29.45

2.49 4.10 3.12 15.06 12.44

10.24 6.34 8.53 81.21 66.98

284.58 738.87 607.91 166.54 145.04

12.79 25.00

71.73 71.00

8.68 17.00

40.76 112.00

414.59 350.00

Zhongnan section, Guizhou Province Sample Ni (ppm) Cu (ppm) ZN0A 25.20 20.20 ZN0B 16.60 32.90 ZN0C 15.90 45.90 ZN1 39.70 28.70 ZN2 33.30 65.10 ZN3 29.40 64.10 ZN4 400.10 149.50 ZN5 37.20 124.90 ZN6 37.70 70.10 ZN7 105.10 91.00 ZN8 67.50 104.30 ZN9 98.40 8.60 ZN10 106.30 8.50 ZN11 189.20 50.30 ZN12 119.60 16.30 ZN13 83.90 1.30 ZN14 100.60 5.30 UCC 44.00 25.00

Zn (ppm) 49.20 35.80 35.70 89.70 65.70 56.90 808.00 59.30 67.60 105.70 130.90 15.60 30.10 201.70 109.00 59.20 21.00 71.00

Ga (ppm) 1.10 2.10 3.10 0.50 -0.10 9.70 21.20 31.10 31.80 38.30 46.40 13.30 2.30 13.50 17.00 20.30 20.30 17.00

Rb (ppm) 9.70 20.30 25.30 8.40 14.00 47.20 112.30 136.30 124.30 186.80 206.20 95.40 16.40 102.60 111.90 127.40 134.00 112.00

Sr (ppm) 294.20 335.40 302.50 694.70 612.50 410.70 407.90 37.00 13.30 44.50 41.60 13.10 106.40 108.40 38.10 22.40 22.50 350.00

Avg. BS UCC

59.99 44.00

335

Wuhe section, Hubei Province Sample Y (ppm) Zr (ppm) YS107 5.67 4.60 YS108 7.32 21.69 YS113 6.58 9.94 YS114 YS115 8.35 6.64 YS0c 214.52 8.07 YS1 37.36 15.52 YS2 17.43 58.71 YS3 17.33 51.86

Nb (ppm) 0.32 0.29 1.20

Mo (ppm) 0.66 0.69 0.97

Cd (ppm) 0.01 0.02 0.12

Sn (ppm) 0.41 0.90 2.23

0.82 0.51 0.90 3.38 4.13

0.31 7.43 8.99 36.53 33.87

0.05 0.12 7.26 0.41 0.22

0.90 0.51 0.55 1.99 1.62

33.54 190.00

2.23 12.00

21.71 1.50

2.00 0.0098

1.17 5.50

Zhongnan section, Guizhou Province Sample Y (ppm) Zr (ppm) ZN0A 117.70 15.80 ZN0B 224.20 18.10 ZN0C 300.00 21.90 ZN1 361.90 11.70 ZN2 495.30 19.00 ZN3 447.70 41.40 ZN4 131.70 77.40 ZN5 84.90 92.10 ZN6 15.30 139.60 ZN7 79.40 296.70 ZN8 114.60 382.90 ZN9 45.80 118.60 ZN10 101.50 25.90 ZN11 169.90 139.10 ZN12 46.90 184.40 ZN13 28.10 206.60 ZN14 42.00 222.90 UCC 22.00 190.00

Nb (ppm) 7.60 11.30 20.30 3.70 4.40 7.80 7.70 11.30 35.10 81.70 118.40 15.70 2.60 10.80 12.80 14.40 15.50 12.00

Mo (ppm) 0.00 0.00 0.00 5.31 18.74 54.38 218.88 84.63 39.30 58.37 91.38 29.10 59.42 80.12 31.22 102.73 183.11 1.50

Avg. BS UCC

71.66 22.00

336

Cd (ppm)

Sn (ppm)

9.29

3.81

0.0098

5.50

Wuhe section, Hubei Province Sample Cs (ppm) Ba (ppm) YS107 3.58 175.26 YS108 2.70 487.30 YS113 4.05 1468.43 YS114 YS115 4.15 210.73 YS0c 0.68 352.96 YS1 10.27 209.75 YS2 6.25 2570.04 YS3 4.11 382.18

La (ppm) 4.53 9.55 17.28

Ce (ppm) 4.60 11.12 16.61

Pr (ppm) 1.11 1.91 3.20

Nd (ppm) 4.44 6.94 12.29

9.32 109.61 16.91 23.89 19.78

8.63 79.27 38.07 38.04 34.42

1.91 24.82 5.10 4.69 4.48

7.68 109.23 20.93 18.19 17.49

878.73 550.00

42.55 30.00

47.45 64.00

9.77 7.10

41.46 26.00

Zhongnan section, Guizhou Province Sample Cs (ppm) Ba (ppm) ZN0A 130.30 ZN0B 376.30 ZN0C 516.50 ZN1 898.20 ZN2 13287.40 ZN3 6793.50 22.80 ZN4 25871.40 ZN5 2847.80 ZN6 2914.90 ZN7 3629.70 ZN8 5147.70 ZN9 2112.50 ZN10 1545.90 ZN11 1957.40 ZN12 2469.50 ZN13 2750.40 ZN14 2574.10 UCC 4.60 550.00

La (ppm) 46.20 90.90 122.60 143.20 173.30 181.20 56.20 17.60 5.50 16.30 71.50 8.90 28.80 51.40 29.90 24.70 30.30 30.00

Ce (ppm) 49.60 83.80 102.50 120.00 156.80 178.40 78.50 32.70 9.50 34.30 154.70 14.40 36.50 61.30 42.10 44.30 55.70 64.00

Avg. BS UCC

5.33 4.60

337

Pr (ppm)

16.14

7.10

Nd (ppm) 48.50 82.20 105.00 128.30 167.90 176.60 66.80 48.00 11.80 36.70 84.10 14.40 41.00 62.40 24.80 23.80 31.90 26.00

Wuhe section, Hubei Province Sample Sm (ppm) Eu (ppm) YS107 0.95 0.21 YS108 1.33 0.32 YS113 2.28 0.61 YS114 YS115 1.35 0.33 YS0c 20.78 4.61 YS1 3.68 0.94 YS2 3.65 1.06 YS3 3.10 0.75 Avg. BS UCC

7.80 4.50

1.84 0.88

Zhongnan section, Guizhou Province Sample Sm (ppm) Eu (ppm) ZN0A ZN0B ZN0C ZN1 ZN2 ZN3 ZN4 2.90 2.83 ZN5 ZN6 ZN7 ZN8 ZN9 ZN10 ZN11 ZN12 ZN13 ZN14 UCC 4.50 0.88

Gd (ppm) 0.84 1.17 2.33

Tb (ppm) 0.11 0.16 0.30

Dy (ppm) 0.76 1.13 1.83

Ho (ppm) 0.14 0.23 0.36

1.50 24.37 4.48 3.42 3.36

0.18 3.02 0.58 0.44 0.44

1.14 20.99 3.62 2.94 2.88

0.22 4.38 0.73 0.62 0.59

8.91 3.80

1.12 0.64

7.61 3.50

1.58 0.80

Gd (ppm)

Tb (ppm)

Dy (ppm)

Ho (ppm)

4.02

3.10

3.40

3.21

3.80

0.64

3.50

0.80

338

Wuhe section, Hubei Province Sample Er (ppm) Tm (ppm) YS107 0.39 0.05 YS108 0.67 0.09 YS113 0.98 0.13 YS114 YS115 0.65 0.07 YS0c 11.74 1.32 YS1 2.10 0.25 YS2 1.97 0.29 YS3 1.84 0.25 Avg. BS UCC

4.41 2.30

0.53 0.33

Zhongnan section, Guizhou Province Sample Er (ppm) Tm (ppm) ZN0A ZN0B ZN0C ZN1 ZN2 ZN3 ZN4 3.22 2.75 ZN5 ZN6 ZN7 ZN8 ZN9 ZN10 ZN11 ZN12 ZN13 ZN14 UCC 2.30 0.33

Yb (ppm) 0.27 0.52 0.71

Lu (ppm) 0.03 0.08 0.10

Hf (ppm) 0.08 0.56 0.42

Ta (ppm) 0.25 0.15 0.42

0.39 5.89 1.18 1.64 1.43

0.05 0.79 0.18 0.25 0.22

0.14 0.12 0.37 1.50 1.25

0.11 0.17 0.21 0.26 0.42

2.53 2.20

0.36 0.32

0.81 5.80

0.27 1.00

Yb (ppm)

Lu (ppm)

Hf (ppm)

Ta (ppm)

2.12

0.83

1.77

0.46

2.20

0.32

5.80

1.00

339

Wuhe section, Hubei Province Sample W (ppm) Pb (ppm) YS107 332.81 1.24 YS108 185.52 3.11 YS113 163.43 11.48 YS114 YS115 46.73 1.94 YS0c 72.98 3.84 YS1 9.70 3.52 YS2 46.48 15.95 YS3 38.96 11.33 Avg. BS UCC

42.03 2.00

8.66 17.00

Zhongnan section, Guizhou Province Sample W (ppm) Pb (ppm) ZN0A 20.90 ZN0B 37.30 ZN0C 73.60 ZN1 16.70 ZN2 23.80 ZN3 25.80 ZN4 34.14 47.30 ZN5 44.10 ZN6 68.90 ZN7 20.00 ZN8 7.70 ZN9 6.90 ZN10 5.20 ZN11 17.50 ZN12 20.80 ZN13 23.30 ZN14 32.70 UCC 2.00 17.00

Bi (ppm) 0.02 0.03 0.04

Th (ppm) 1.04 2.43 2.23

0.02 0.04 0.04 0.18 0.20 0.11 0.00127

Bi (ppm)

0.24

0.00127

340

U (ppm)

Mo/Sc 2.49 3.20 2.99

0.29 0.12 0.18

1.15 3.28 0.84 6.53 5.51

1.25 70.01 119.32 35.41 17.99

0.16 3.91 3.88 3.13 3.87

4.04 10.70

60.68 2.80

3.70 0.11

Th (ppm) -8.20 -14.60 -31.00 -3.50 -4.00 -3.30 4.00 5.30 1.90 14.20 33.50 6.10 -0.10 5.90 6.50 8.00 9.80 10.70

U (ppm)

Mo/Sc

0.00

32.01

2.80

6.94 11.82 25.75 8.30 3.42 3.97 29.48 2.97 21.22 7.22 2.35 7.13 11.81 0.11

Wuhe section, Hubei Province Sample V/Sc U/Sc YS107 12.06 1.08 YS108 16.61 0.55 YS113 4.79 0.56 YS114 YS115 8.36 0.65 YS0c 138.14 36.80 YS1 12.18 51.52 YS2 13.97 3.04 YS3 12.57 2.06 Avg. BS UCC

44.21 7.87

23.35 0.21

Zhongnan section, Guizhou Province Sample V/Sc U/Sc ZN0A ZN0B ZN0C 722.31 ZN1 ZN2 296.26 ZN3 203.74 ZN4 34.68 3.77 ZN5 24.70 ZN6 9.86 ZN7 143.82 ZN8 990.06 ZN9 151.54 ZN10 174.04 ZN11 546.82 ZN12 217.98 ZN13 467.51 ZN14 406.54 UCC 7.87 0.21

Mo/TOC (10-4)

V/TOC (10-4)

Th/U

V/(V+Ni)

6.50 2.38 2.80 0.00 0.72 3.25 13.34 10.70 31.48

274.53 331.92 74.51 0.00 37.39 114.99 41.84 47.73 102.25

0.42 0.76 0.75

0.95 0.92 0.60

0.92 0.05 0.01 0.18 0.31

0.73 0.96 0.32 0.66 0.56

14.69

76.70

0.14 3.82

0.63 0.71

Mo/TOC (10-4)

0.00 0.00 0.00 11.31 40.87 85.58 1346.49 496.64 219.77 6.05 48.54 3.24 6.25 7.23 3.90 14.59 21.26

V/TOC (10-4)

218.23 1684.01 1948.87 1632.33 1744.42 1474.90 1813.49 1478.19 634.14 219.13 1630.33 165.50 51.26 548.02 361.64 955.86 731.73

Th/U

V/(V+Ni)

0.12

3.82

341

0.87 0.98 0.99 0.95 0.96 0.97 0.42 0.87 0.75 0.95 0.98 0.94 0.82 0.97 0.96 0.99 0.98 0.71

Xiaotan section, Sichuan Province Sample Distance (m) Formation XT1 0 Shiyantou XT2 0.3 Shiyantou XT3 1.3 Shiyantou XT4 2.3 Shiyantou XT5 3.6 Shiyantou XT6 5.1 Shiyantou XT7 6.1 Shiyantou XT8 7.1 Shiyantou XT9 8.1 Shiyantou XT10 9.6 Shiyantou XT11 10.6 Shiyantou XT12 12 Shiyantou XT13 13.5 Shiyantou XT14 14.5 Shiyantou XT15 15.5 Shiyantou XT16 16.5 Shiyantou XT17 18.5 Shiyantou XT18 20.3 Shiyantou XT19 21.3 Shiyantou XT20 22.6 Shiyantou XT21 24.1 Shiyantou XT22 25.1 Shiyantou XT23 26.1 Shiyantou XT24 27.9 Shiyantou XT25 29.9 Shiyantou XT26 30.9 Shiyantou XT27 31.9 Shiyantou XT28 33.9 Shiyantou XT29 36.4 Shiyantou Average in black shale Upper Continental Crust

Position: 28° 7'28.68"N, 103°27'58.96"E Lithology Si (%) Al (%) Carbonate 5.03 1.90 Black shale 26.67 4.41 Black shale 32.90 5.39 Black shale 32.02 4.96 Black shale 33.54 4.40 Black shale 33.10 4.78 Black shale 32.67 4.98 Black shale 29.79 5.63 Black shale 31.14 4.75 Black shale 30.88 5.42 Black shale 30.10 5.66 Black shale 30.44 6.67 Black shale 31.67 6.16 Black shale 31.31 6.51 Black shale 29.53 6.40 Black shale 29.42 6.89 Black shale 30.01 6.78 Black shale 29.48 7.04 Black shale 30.40 6.83 Black shale 28.76 6.97 Black shale 28.79 6.91 Black shale 29.76 6.82 Black shale 28.38 7.21 Black shale 27.95 7.26 Black shale 29.51 7.10 Black shale 28.96 7.43 Black shale 30.18 7.40 Black shale 28.62 7.65 Black shale 29.20 7.55 30.19 6.28 30.80 8.04

342

Fe (%) 2.02 3.37 1.05 1.72 1.83 1.78 1.74 1.58 1.69 1.54 1.74 1.28 1.15 1.36 1.78 1.66 2.41 1.60 1.65 1.85 1.84 2.15 1.74 2.41 2.04 1.76 1.48 3.58 2.63 1.87 3.50

Xiaotan section, Sichuan Province Sample Mg (%) Ca (%) XT1 2.36 2.57 XT2 1.34 5.96 XT3 0.78 7.28 XT4 1.42 6.69 XT5 1.13 5.94 XT6 1.08 6.45 XT7 0.91 6.72 XT8 0.98 7.60 XT9 0.88 6.41 XT10 0.52 7.32 XT11 0.56 7.64 XT12 0.92 9.01 XT13 0.54 8.32 XT14 0.73 8.78 XT15 0.89 8.64 XT16 1.07 9.30 XT17 1.15 9.16 XT18 1.01 9.50 XT19 0.84 9.22 XT20 0.96 9.41 XT21 1.07 9.33 XT22 0.81 9.21 XT23 1.02 9.73 XT24 1.17 9.80 XT25 0.99 9.59 XT26 1.01 10.03 XT27 0.94 9.99 XT28 1.96 10.34 XT29 1.43 10.19 Avg. BS 1.00 8.48 UCC 1.33 3.00

Na (%)

K (%) 0.08 0.56 0.89 0.77 0.78 1.13 0.92 1.20 0.70 1.21 1.02 1.58 1.57 1.60 1.34 1.36 1.67 1.82 1.97 1.75 1.58 1.87 1.66 1.69 1.98 1.68 1.81 1.80 1.90 1.42 2.89

343

P (%) 0.23 1.76 2.39 1.82 1.60 1.73 2.03 2.35 2.09 2.42 2.70 2.77 2.63 2.76 2.93 3.01 2.55 2.76 2.64 2.86 2.84 2.79 2.99 2.89 2.66 3.13 3.13 2.65 2.83 2.56 2.80

TC (%) 0.99 0.89 0.20 0.40 0.27 0.11 0.46 0.69 0.37 0.28 0.22 0.15 0.11 0.15 0.12 0.12 0.13 0.08 0.09 0.11 0.10 0.10 0.09 0.11 0.08 0.11 0.11 0.09 0.09 0.21 0.07

6.80 4.90 2.04 1.99 1.78 1.70 2.40 3.35 4.15 4.03 4.10 2.99 2.21 2.35 3.22 3.34 2.30 3.27 2.56 4.21 3.81 2.89 3.40 3.38 2.84 2.62 1.58 1.03 0.91 2.83

Xiaotan section, Sichuan Province Sample TS (%) TOC (%) XT1 0.01 XT2 0.05 XT3 0.07 XT4 0.03 XT5 0.02 XT6 0.33 XT7 0.07 XT8 0.06 XT9 0.13 XT10 0.10 XT11 0.18 XT12 0.11 XT13 0.20 XT14 0.09 XT15 0.28 XT16 0.05 XT17 0.05 XT18 0.04 XT19 0.04 XT20 0.05 XT21 0.07 XT22 0.10 XT23 0.14 XT24 0.06 XT25 0.05 XT26 0.06 XT27 0.05 XT28 0.01 XT29 0.03 Avg. BS 0.09 UCC

0.13 5.02 2.19 2.02 1.98 1.94 2.68 3.79 4.26 3.62 4.15 3.17 2.10 2.19 3.33 3.67 2.31 2.95 2.55 4.01 3.82 2.86 3.41 3.36 2.87 2.55 1.63 1.02 0.93 2.87

Pyrite S (%) 0.01 0.01 0.00 0.00 0.00 0.05 0.00 0.01 0.01 0.01 0.01 0.01 0.02 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.02 0.01 0.01 0.01 0.01 0.01 0.01 0.01

344

34

δ S pyrite

Li (ppm)

Be (ppm)

27.67

1.34

20.00

3.00

Xiaotan section, Sichuan Province Sample Sc (ppm) Ti (ppm) XT1 4.60 645.77 XT2 9.70 2099.26 XT3 10.50 2644.27 XT4 9.10 2285.69 XT5 8.70 2111.67 XT6 9.20 2702.11 XT7 10.60 2788.42 XT8 14.70 3333.92 XT9 10.10 2687.08 XT10 12.80 3268.79 XT11 13.20 3412.99 XT12 15.50 3908.53 XT13 14.50 4052.58 XT14 15.80 4159.64 XT15 14.20 4013.10 XT16 16.30 4255.51 XT17 15.40 4166.62 XT18 14.40 4339.59 XT19 16.10 4189.55 XT20 16.30 4495.82 XT21 16.00 4302.52 XT22 15.60 4571.69 XT23 16.60 4545.78 XT24 17.50 4607.75 XT25 16.30 4709.54 XT26 18.50 5179.95 XT27 16.70 5032.90 XT28 16.00 4496.29 XT29 17.10 4513.12 Avg. BS 14.19 3816.95 UCC 13.60 4100.00

V (ppm) 71.20 761.70 318.00 242.60 235.20 215.70 312.50 569.80 1138.60 699.60 1971.10 387.30 503.70 542.70 2147.90 2056.00 320.40 640.70 413.70 411.40 955.50 734.80 1077.90 288.60 215.40 255.50 537.40 166.10 217.00 654.89 107.00

345

Cr (ppm) 15.70 195.80 120.00 110.60 79.10 91.80 195.30 259.60 349.20 169.30 323.90 110.00 141.30 184.70 255.70 197.40 124.30 99.10 93.90 106.90 115.40 117.40 128.70 110.00 97.60 104.60 107.50 102.20 104.50 149.85 83.00

Mn (ppm) 688.41 83.04 73.01 101.84 88.02 72.89 58.59 42.94 49.80 49.86 42.54 79.36 79.89 87.40 99.86 107.54 130.61 107.42 101.32 78.12 85.20 93.65 106.54 99.47 122.57 86.36 109.61 198.31 124.23 91.43 600.00

Co (ppm)

30.96

17.00

Xiaotan section, Sichuan Province Sample Ni (ppm) Cu (ppm) XT1 6.10 5.90 XT2 87.20 57.90 XT3 18.70 7.20 XT4 40.00 37.70 XT5 40.40 30.20 XT6 32.10 27.00 XT7 39.70 25.90 XT8 34.80 9.20 XT9 74.80 20.90 XT10 55.00 10.80 XT11 107.90 9.50 XT12 37.60 8.20 XT13 23.80 3.10 XT14 33.50 8.00 XT15 58.30 18.20 XT16 52.90 12.10 XT17 38.20 22.00 XT18 48.30 10.50 XT19 45.50 19.00 XT20 57.60 14.00 XT21 85.00 22.30 XT22 61.50 16.10 XT23 65.30 22.30 XT24 52.50 18.20 XT25 38.80 15.90 XT26 26.70 12.30 XT27 19.20 5.70 XT28 44.80 23.40 XT29 31.30 15.10 Avg. BS 48.26 17.95 UCC 44.00 25.00

Zn (ppm) 54.20 189.60 65.00 124.00 98.60 85.90 98.00 60.20 149.10 278.40 518.10 77.60 98.60 29.50 58.60 68.60 69.50 65.00 42.70 61.20 198.20 123.60 144.70 64.30 98.20 106.20 39.30 68.10 46.00 111.67 71.00

346

Ga (ppm) 5.90 11.80 15.70 12.40 11.60 12.10 13.40 15.80 13.40 15.20 17.50 18.40 16.90 18.30 19.60 19.70 17.10 18.60 18.30 19.80 19.50 18.80 21.10 20.20 19.40 22.20 22.50 20.60 21.60 17.55 17.00

Rb (ppm) 21.50 96.40 124.00 90.80 78.30 79.80 98.40 119.00 108.30 119.30 138.90 129.70 121.50 128.10 146.10 149.90 115.80 124.10 117.80 133.20 133.60 126.80 142.20 136.70 118.20 147.00 142.70 117.00 126.90 121.80 112.00

Sr (ppm) 1299.30 172.90 41.50 86.20 65.60 62.70 74.90 118.90 62.10 61.70 76.00 80.10 77.70 76.60 72.50 68.00 74.60 95.20 85.80 85.00 81.50 80.60 84.70 103.90 82.60 79.10 85.90 72.30 79.40 81.71 350.00

Xiaotan section, Sichuan Province Sample Y (ppm) Zr (ppm) XT1 53.10 73.50 XT2 88.30 147.20 XT3 16.70 187.10 XT4 44.30 128.60 XT5 24.40 105.30 XT6 14.70 131.00 XT7 28.00 142.30 XT8 36.80 144.10 XT9 36.60 135.10 XT10 27.90 162.30 XT11 28.00 174.80 XT12 24.40 195.70 XT13 23.80 200.10 XT14 26.80 195.40 XT15 24.80 189.70 XT16 26.90 199.20 XT17 27.30 211.80 XT18 24.30 211.80 XT19 33.20 216.60 XT20 26.40 231.40 XT21 27.40 217.00 XT22 28.70 249.90 XT23 31.00 252.40 XT24 28.20 240.50 XT25 24.90 253.70 XT26 24.40 244.90 XT27 16.50 225.70 XT28 26.50 179.80 XT29 20.40 183.90 Avg. BS 28.99 191.33 UCC 22.00 190.00

Nb (ppm) 4.20 12.40 13.90 11.60 9.00 10.00 11.40 11.60 11.40 12.90 12.90 13.50 13.10 13.70 13.40 14.00 14.00 13.90 13.40 15.20 14.20 14.60 16.90 15.70 15.50 17.30 16.50 14.30 14.70 13.61 12.00

347

Mo (ppm) 2.50 20.03 2.44 2.03 2.90 2.40 3.24 10.40 7.22 9.78 7.20 6.79 4.19 4.39 8.34 7.16 4.90 12.67 11.03 18.48 14.24 9.55 11.87 14.03 17.56 14.30 14.98 3.80 3.00 8.89 1.50

Cd (ppm)

Sn (ppm)

0.22

2.30

0.0098

5.50

Xiaotan section, Sichuan Province Sample Cs (ppm) Ba (ppm) XT1 384.70 XT2 849.80 XT3 977.20 XT4 690.50 XT5 635.50 XT6 3.80 651.10 XT7 765.10 XT8 1034.60 XT9 829.00 XT10 1020.20 XT11 1150.80 XT12 1192.90 XT13 1078.40 XT14 1095.00 XT15 1200.80 XT16 1230.10 XT17 1076.20 XT18 1095.60 XT19 1231.30 XT20 1290.00 XT21 1240.30 XT22 1161.40 XT23 1257.10 XT24 1264.90 XT25 1125.60 XT26 1310.20 XT27 1269.90 XT28 1052.10 XT29 1272.70 Avg. BS 1073.15 UCC 4.60 550.00

La (ppm) 29.90 44.80 17.70 19.40 12.70 10.80 14.70 21.80 20.60 22.60 24.80 26.40 22.90 23.60 20.80 23.20 21.90 23.60 24.30 27.00 23.50 26.90 25.00 29.70 24.30 31.50 22.70 24.30 24.60 23.43 30.00

348

Ce (ppm) 47.90 89.40 26.20 37.60 26.10 16.00 25.30 37.20 34.40 38.70 44.80 47.50 40.30 41.50 39.20 45.10 42.50 46.30 49.50 50.60 45.30 52.00 48.60 59.40 48.50 62.00 42.10 48.20 46.30 43.95 64.00

Pr (ppm)

3.59

7.10

Nd (ppm) 28.20 55.30 12.30 24.40 14.80 7.80 16.80 25.30 21.50 19.30 24.60 20.60 16.30 19.90 18.10 20.30 20.80 22.80 23.90 21.40 22.10 24.40 23.60 24.90 20.50 24.90 17.30 22.10 20.20 21.65 26.00

Xiaotan section, Sichuan Province Sample Sm (ppm) Eu (ppm) XT1 XT2 XT3 XT4 XT5 XT6 2.76 0.62 XT7 XT8 XT9 XT10 XT11 XT12 XT13 XT14 XT15 XT16 XT17 XT18 XT19 XT20 XT21 XT22 XT23 XT24 XT25 XT26 XT27 XT28 XT29 Avg. BS UCC 4.50 0.88

Gd (ppm)

Tb (ppm)

Dy (ppm)

Ho (ppm)

2.81

0.40

2.67

0.56

3.80

0.64

3.50

0.80

349

Xiaotan section, Sichuan Province Sample Er (ppm) Tm (ppm) XT1 XT2 XT3 XT4 XT5 XT6 1.69 0.23 XT7 XT8 XT9 XT10 XT11 XT12 XT13 XT14 XT15 XT16 XT17 XT18 XT19 XT20 XT21 XT22 XT23 XT24 XT25 XT26 XT27 XT28 XT29 Avg. BS UCC 2.30 0.33

Yb (ppm)

Lu (ppm)

Hf (ppm)

Ta (ppm)

1.34

0.21

0.20

0.30

2.20

0.32

5.80

1.00

350

Xiaotan section, Sichuan Province Sample W (ppm) Pb (ppm) XT1 9.40 XT2 16.60 XT3 11.30 XT4 8.80 XT5 8.20 XT6 66.72 10.70 XT7 12.20 XT8 19.40 XT9 13.30 XT10 17.50 XT11 16.40 XT12 16.90 XT13 25.80 XT14 26.50 XT15 19.50 XT16 19.50 XT17 23.60 XT18 35.50 XT19 26.10 XT20 33.80 XT21 28.50 XT22 30.40 XT23 29.30 XT24 31.50 XT25 44.10 XT26 36.80 XT27 33.10 XT28 21.30 XT29 24.70 Avg. BS 22.90 UCC 2.00 17.00

Bi (ppm)

0.24

0.24 0.00127

351

Th (ppm) 3.20 7.70 10.10 6.60 5.20 7.00 7.40 8.40 7.40 7.70 8.20 9.90 9.60 10.30 8.10 9.70 10.40 9.40 9.00 10.90 9.50 11.70 11.10 11.60 12.30 13.70 12.00 10.20 11.30 9.51 10.70

U (ppm)

Mo/Sc

2.95

2.95 2.80

0.54 2.07 0.23 0.22 0.33 0.26 0.31 0.71 0.71 0.76 0.55 0.44 0.29 0.28 0.59 0.44 0.32 0.88 0.68 1.13 0.89 0.61 0.71 0.80 1.08 0.77 0.90 0.24 0.18 0.62 0.11

Xiaotan section, Sichuan Province Sample V/Sc U/Sc XT1 15.48 XT2 78.53 XT3 30.29 XT4 26.66 XT5 27.03 XT6 23.45 0.32 XT7 29.48 XT8 38.76 XT9 112.73 XT10 54.66 XT11 149.33 XT12 24.99 XT13 34.74 XT14 34.35 XT15 151.26 XT16 126.13 XT17 20.81 XT18 44.49 XT19 25.70 XT20 25.24 XT21 59.72 XT22 47.10 XT23 64.93 XT24 16.49 XT25 13.21 XT26 13.81 XT27 32.18 XT28 10.38 XT29 12.69 Avg. BS 47.47 UCC 7.87 0.21

Mo/TOC (10-4)

19.47 3.99 1.12 1.00 1.46 1.23 1.21 2.74 1.70 2.70 1.74 2.14 2.00 2.01 2.50 1.95 2.12 4.29 4.32 4.61 3.73 3.34 3.48 4.17 6.11 5.61 9.18 3.73 3.22 3.12

V/TOC (10-4)

553.84 151.64 145.43 119.81 118.67 111.01 116.74 150.19 267.53 193.46 474.99 122.10 239.96 248.24 645.34 560.87 138.56 217.08 161.95 102.68 250.38 257.18 315.98 85.89 74.92 100.14 329.39 162.89 232.92 217.71

Th/U

V/(V+Ni)

2.37

3.82

352

0.92 0.90 0.94 0.86 0.85 0.87 0.89 0.94 0.94 0.93 0.95 0.91 0.95 0.94 0.97 0.97 0.89 0.93 0.90 0.88 0.92 0.92 0.94 0.85 0.85 0.91 0.97 0.79 0.87 0.91 0.71

Xiaotan section, Sichuan Province Sample Distance (m) Formation XTY1 0 Upper Shiyantou XTY2 1 Upper Shiyantou XTY3 2.3 Upper Shiyantou XTY4 6.9 Upper Shiyantou XTY5 12.9 Upper Shiyantou XTY6 13.9 Upper Shiyantou XTY7 14.9 Upper Shiyantou XTY8 15.4 Upper Shiyantou XTY9 20 Upper Shiyantou XTY10 21 Upper Shiyantou XTY11 22 Upper Shiyantou XTY12 23 Upper Shiyantou XTY13 24 Upper Shiyantou XTY14 25 Upper Shiyantou XTY15 26 Upper Shiyantou XTY16 27.5 Upper Shiyantou XTY17 28.5 Upper Shiyantou XTY17a 28.68 Upper Shiyantou XTY17b 28.88 Upper Shiyantou XTY17c 29.03 Upper Shiyantou XTY17d 29.18 Upper Shiyantou XTY17e 29.28 Upper Shiyantou XTY17f 29.41 Upper Shiyantou XTY18 29.53 Upper Shiyantou XTY18a 29.68 Upper Shiyantou XTY18b 29.83 Upper Shiyantou XTY18c 30.03 Upper Shiyantou XTY18d 30.16 Upper Shiyantou XTY18e 30.28 Upper Shiyantou XTY19 30.42 Upper Shiyantou XTY19a 30.57 Upper Shiyantou XTY19b 30.77 Upper Shiyantou XTY19c 30.89 Upper Shiyantou XTY19d 31.07 Upper Shiyantou XTY19e 31.27 Upper Shiyantou XTY19f 31.44 Upper Shiyantou XTY20 31.64 Upper Shiyantou XTY21 32.6 Upper Shiyantou XTY22 33.6 Upper Shiyantou XTY23 34.6 Upper Shiyantou XTY24 35.6 Upper Shiyantou XTY25 36.6 Upper Shiyantou XTY26 37.6 Upper Shiyantou XTY27 38.6 Upper Shiyantou XTY28 39.6 Upper Shiyantou XTY29 40.6 Upper Shiyantou XTY30 42 Upper Shiyantou XTY31 52 Upper Shiyantou

Position: 28° 7'28.68"N, 103°27'58.96"E Lithology Si (%) Al (%) Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Black shale Shale Shale Shale

353

Fe (%) 1.60 2.65 3.09 2.64 2.01 2.25 2.30 1.70 1.67 1.48 1.56 2.09 2.45 2.29 2.24 1.33 2.65 2.46 2.16 1.82 2.13 2.34 1.74 2.21 3.14 1.75 1.75 1.61 2.24 1.76 1.63 1.99 1.90 1.41 2.82 1.72 3.04 1.79 1.96 3.26 1.68 2.44 2.76 4.44 2.53 2.95 4.27 2.72

XTY32 62 Upper Shiyantou XTY33 72 Upper Shiyantou Average in black shale (excl. XTY28) UCC Xiaotan section, Sichuan Province Sample Mg (%) Ca (%) XTY1 XTY2 XTY3 XTY4 XTY5 XTY6 XTY7 XTY8 XTY9 XTY10 XTY11 XTY12 XTY13 XTY14 XTY15 XTY16 XTY17 XTY17a XTY17b XTY17c XTY17d XTY17e XTY17f XTY18 XTY18a XTY18b XTY18c XTY18d XTY18e XTY19 XTY19a XTY19b XTY19c XTY19d XTY19e XTY19f XTY20 XTY21 XTY22 XTY23 XTY24 XTY25 XTY26

Shale Shale

2.49 2.68 2.13 3.50

Na (%)

K (%)

P (%)

TC (%) 2.23 0.70 0.65 1.66 1.40 1.53 1.07 1.40 1.53 1.26 1.94 2.06 1.80 1.80 1.81 2.13 1.83 2.05 1.73 2.00 1.97 2.04 1.97 2.02 1.79 2.18 2.12 2.13 2.11 2.13 1.99 2.10 2.10 1.36 2.10 2.08 2.12 2.21 1.91 1.95 2.08 2.02 2.26

354

XTY27 XTY28 XTY29 XTY30 XTY31 XTY32 XTY33 Avg. BS UCC Xiaotan section, Sichuan Province Sample TS (%) TOC (%) XTY1 0.02 XTY2 0.01 XTY3 0.01 XTY4 0.03 XTY5 0.02 XTY6 0.03 XTY7 0.01 XTY8 0.02 XTY9 0.05 XTY10 0.01 XTY11 0.03 XTY12 0.03 XTY13 0.04 XTY14 0.45 XTY15 0.54 XTY16 0.03 XTY17 0.22 XTY17a 0.40 XTY17b 0.05 XTY17c 0.04 XTY17d 0.18 XTY17e 0.22 XTY17f 0.12 XTY18 0.26 XTY18a 0.02 XTY18b 0.23 XTY18c 0.05 XTY18d 0.05 XTY18e 0.04 XTY19 0.03 XTY19a 0.02 XTY19b 0.02 XTY19c 0.04 XTY19d 0.05 XTY19e 0.13 XTY19f 0.05 XTY20 0.79 XTY21 0.05

1.83 2.23 0.49 0.37 0.56 0.59 0.37 1.84

2.30 0.75 0.74 1.65 1.42 1.57 1.01 1.48 1.55 1.29 1.99 2.06 1.88 1.79 1.87 2.17 1.87 2.04 1.70 1.99 1.92 2.02 1.98 2.06 1.75 2.15 2.19 2.11 2.12 2.17 1.97 2.10 2.09 1.36 2.09 2.19 2.06 2.16

Pyrite S (%) 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.02 0.01 0.01 0.01 0.01 0.13 0.20 0.01 0.00 0.02 0.00 0.01 0.03 0.03 0.02 0.11 0.00 0.02 0.01 0.00 0.01 0.01 0.08 0.00 0.08 0.01 0.02 0.01 0.14 0.00

355

34

δ S pyrite

-11.87

-3.65

-10.41

Li (ppm) 20.29

Be (ppm) 1.51

35.11

1.83

37.95 30.19 26.52 34.91 29.48 35.43 40.63 36.74 35.29 29.49 32.74 31.12 34.27 31.25

1.67 1.58 2.01 2.74 1.87 1.52 1.81 1.60 1.63 1.57 1.82 1.94 1.99 1.84

30.69 65.43 34.46 42.97 37.48 27.28 29.98 35.88 27.78 31.72 30.54 32.17 27.65 37.00 25.31 30.38 30.20

1.74 4.54 1.83 2.02 1.76 1.90 2.06 1.88 1.92 2.01 2.10 2.05 1.94 1.99 1.97 1.83 1.92

XTY22 XTY23 XTY24 XTY25 XTY26 XTY27 XTY28 XTY29 XTY30 XTY31 XTY32 XTY33 Avg. BS UCC

0.05 0.72 0.05 0.08 1.52 0.07 0.53 0.01 0.03 0.00 0.00 0.22 0.16

1.86 1.92 2.16 2.03 2.25 1.54 2.26 0.47 0.37 0.20 0.28 0.13 1.86

Xiaotan section, Sichuan Province Sample Sc (ppm) Ti (ppm) XTY1 13.96 1375.60 XTY2 XTY3 XTY4 XTY5 18.76 2163.85 XTY6 XTY7 16.37 2336.43 XTY8 17.24 1550.41 XTY9 25.33 3289.49 XTY10 31.50 3568.04 XTY11 21.18 1969.98 XTY12 15.51 1772.22 XTY13 17.32 1909.55 XTY14 24.02 1501.92 XTY15 18.50 1685.24 XTY16 14.72 1730.76 XTY17 18.98 1607.27 XTY17a 20.31 2296.07 XTY17b 21.57 2695.57 XTY17c 21.27 1863.86 XTY17d XTY17e 27.12 1521.55 XTY17f 52.78 3129.47 XTY18 20.99 1934.20 XTY18a 20.61 1800.20 XTY18b 28.89 1721.08 XTY18c 21.17 1906.09 XTY18d 21.42 2086.65 XTY18e 20.98 2072.32 XTY19 21.14 1761.06 XTY19a 22.32 2058.27 XTY19b 20.62 2240.81 XTY19c 22.64 2311.60

0.01 0.07 0.01 0.01 0.10 0.00 0.07 0.00 0.00

-14.25

-14.47 -17.46

32.40 32.07 18.98 27.37 30.79 32.73 250.98 56.00 51.81 28.51 25.94 31.20 32.63 20.00

2.12 2.09 1.36 2.45 1.93 1.94 19.40 1.87 2.29

0.03

-10.93

V (ppm) 102.05

Cr (ppm) 76.27

Mn (ppm) 67.97

Co (ppm) 20.79

108.72

96.10

137.22

37.04

94.30 99.30 133.00 151.09 190.09 106.29 120.71 129.30 147.85 96.29 172.18 183.26 151.72 153.51

83.33 88.58 119.55 131.94 116.50 83.47 94.67 100.51 95.67 101.82 99.07 103.67 101.51 113.91

154.40 111.10 92.26 100.18 82.61 123.80 159.04 125.24 157.85 117.47 138.36 146.14 149.12 127.44

43.61 37.23 28.98 31.53 83.42 28.28 19.82 15.53 34.74 42.55 24.49 46.09 32.60 32.62

137.06 306.39 159.32 145.40 155.88 272.67 248.11 226.99 134.40 139.10 159.63 198.24

109.01 227.43 106.58 100.84 120.01 104.06 103.63 103.33 101.04 102.16 103.45 111.28

195.92 379.01 138.81 165.90 155.74 89.96 195.57 159.48 92.12 118.55 119.83 129.00

27.64 56.11 38.72 29.57 39.11 41.25 41.24 34.17 33.48 22.81 25.99 29.56

356

1.96 3.00

XTY19d XTY19e XTY19f XTY20 XTY21 XTY22 XTY23 XTY24 XTY25 XTY26 XTY27 XTY28 XTY29 XTY30 XTY31 XTY32 XTY33 Avg. BS UCC

20.94 21.75 20.99 20.99 22.77 21.40 26.99 16.33 31.16 22.41 17.63 185.44 20.64 27.22 8.16 6.82 8.29 22.18 13.60

2375.77 1864.55 2071.10 1682.12 2314.48 2040.24 1480.90 1506.22 2049.25 2220.96 1523.27 2803.22 1774.23 1812.39 3477.90 3476.08 3680.83 2038.56 4100.00

Xiaotan section, Sichuan Province Sample Ni (ppm) Cu (ppm) XTY1 18.22 11.60 XTY2 XTY3 XTY4 XTY5 25.14 12.40 XTY6 XTY7 23.86 15.82 XTY8 21.70 12.96 XTY9 12.88 15.24 XTY10 20.17 16.20 XTY11 17.00 20.92 XTY12 25.88 13.02 XTY13 31.03 13.69 XTY14 29.25 13.67 XTY15 31.05 21.67 XTY16 61.05 13.95 XTY17 32.60 15.73 XTY17a 28.13 22.49 XTY17b 26.54 23.68 XTY17c 28.66 18.49 XTY17d XTY17e 28.11 17.48 XTY17f 56.07 28.77 XTY18 29.20 17.00 XTY18a 38.91 16.61 XTY18b 29.46 17.19 XTY18c 27.70 14.13 XTY18d 31.77 23.54

222.50 247.05 208.20 183.18 203.66 166.47 115.05 104.78 139.88 180.21 122.16 226.24 140.41 127.56 61.85 57.25 64.73 163.00 107.00

100.17 104.95 96.44 101.79 111.59 105.14 115.21 92.19 132.04 113.51 92.79 227.07 105.37 118.62 65.69 61.76 68.69 107.17 83.00

103.75 157.52 90.44 139.45 144.89 120.63 132.83 87.66 128.81 189.86 3379.41 5126.75 202.58 328.12 262.92 248.16 169.07 137.52 600.00

17.91 39.68 40.77 35.03 28.00 20.52 21.81 29.92 34.10 47.01 144.39 132.23 24.16 30.87

Zn (ppm) 92.51

Ga (ppm) 19.75

Rb (ppm) 109.69

Sr (ppm) 81.85

78.79

26.03

131.68

114.58

134.19 88.15 81.17 87.89 75.55 92.95 88.40 87.56 133.91 99.15 105.77 84.35 79.43 86.55

20.54 23.56 31.75 35.05 25.51 20.49 22.03 17.44 22.25 19.90 22.01 24.31 26.92 26.19

101.36 110.09 152.69 170.76 132.07 100.81 109.85 87.60 110.39 102.47 117.68 139.35 145.52 136.78

95.37 108.31 90.45 97.20 104.77 75.82 76.50 82.67 78.86 73.39 84.02 80.35 87.42 95.48

92.17 176.31 96.74 130.05 112.76 103.57 124.07

21.44 29.93 24.06 24.52 20.33 24.90 25.14

141.68 142.63 129.21 126.34 110.56 131.65 135.71

104.39 104.32 82.31 85.47 79.04 94.75 102.19

357

34.04 17.00

XTY18e XTY19 XTY19a XTY19b XTY19c XTY19d XTY19e XTY19f XTY20 XTY21 XTY22 XTY23 XTY24 XTY25 XTY26 XTY27 XTY28 XTY29 XTY30 XTY31 XTY32 XTY33 Avg. BS UCC

36.64 22.06 18.80 24.17 23.60 17.62 60.29 23.35 37.76 27.09 23.99 25.13 14.42 25.11 36.52 285.50 556.75 28.07 44.82 23.15 20.38 23.22 28.71 44.00

28.33 18.12 21.98 18.34 17.09 11.66 19.41 15.42 25.04 17.08 16.14 19.78 11.09 16.79 29.32 26.05 48.25 13.01 20.15 18.24 12.01 10.01 17.94 25.00

Xiaotan section, Sichuan Province Sample Y (ppm) Zr (ppm) XTY1 2.56 XTY2 XTY3 XTY4 XTY5 6.22 XTY6 XTY7 7.54 XTY8 4.95 XTY9 5.17 XTY10 5.68 XTY11 4.18 XTY12 3.70 XTY13 4.82 XTY14 5.40 XTY15 4.81 XTY16 3.58 XTY17 6.05 XTY17a 4.38 XTY17b 4.69 XTY17c 3.93 XTY17d XTY17e 6.07 XTY17f 6.73

104.20 75.11 84.05 80.07 74.32 83.28 108.32 84.17 113.33 140.73 91.75 83.24 60.36 93.79 118.54 195.21 1345.59 82.84 113.22 31.08 26.61 32.68 98.08 71.00

24.50 24.21 26.69 24.48 26.11 25.18 25.65 24.26 22.82 25.61 24.74 21.24 21.96 27.03 25.00 22.89 54.18 25.79 20.48

24.30 17.00

128.53 133.49 145.89 134.84 143.12 132.33 136.40 132.56 123.53 140.68 132.19 122.68 118.13 148.78 135.32 103.92 202.84 118.44 94.60 44.59 33.29 51.56 128.55 112.00

97.04 93.07 84.15 87.72 93.82 75.27 82.66 91.23 79.10 101.92 83.61 78.38 84.19 97.34 88.01 93.57 149.47 93.14 82.00 59.80 49.90 42.35 89.40 350.00

3.40

Nb (ppm) 1.68

Mo (ppm) 4.98

Cd (ppm) 0.14

Sn (ppm) 2.29

6.33

1.78

1.45

0.09

3.03

5.72 4.14 7.89 8.37 5.84 3.53 4.14 5.99 4.74 4.03 4.64 6.18 7.00 5.30

1.16 1.13 4.58 4.92 2.92 1.57 3.49 4.33 1.97 1.78 2.44 0.71 2.77 0.75

1.19 1.76 16.44 18.47 13.06 2.63 2.06 6.63 6.87 10.88 6.19 5.63 5.50 5.14

1.02 0.11 0.08 0.03 0.18 0.12 0.10 0.48 0.19 0.07 0.06 0.08 0.12 0.08

2.24 2.31 3.69 2.91 2.82 2.37 2.86 7.36 2.29 2.41 2.23 2.65 2.85 2.79

7.01 7.13

2.62 2.83

5.67 5.37

0.20 0.24

7.38 11.69

358

XTY18 XTY18a XTY18b XTY18c XTY18d XTY18e XTY19 XTY19a XTY19b XTY19c XTY19d XTY19e XTY19f XTY20 XTY21 XTY22 XTY23 XTY24 XTY25 XTY26 XTY27 XTY28 XTY29 XTY30 XTY31 XTY32 XTY33 Avg. BS UCC

4.94 6.75 5.35 6.99 5.16 5.76 4.65 4.25 4.52 4.27 3.65 7.68 4.69 6.54 5.86 4.98 3.81 4.35 5.67 5.47 13.44 15.90 5.57 9.56 25.94 29.87 23.37 5.15 22.00

5.20 5.15 5.89 5.36 5.74 5.83 5.27 5.50 5.86 6.46 5.93 5.48 5.85 4.95 6.96 6.04 4.58 5.17 6.62 6.28 5.15 9.68 4.63 4.85 64.83 95.26 98.00 5.67 190.00

Xiaotan section, Sichuan Province Sample Cs (ppm) Ba (ppm) XTY1 3.95 979.94 XTY2 XTY3 XTY4 XTY5 5.50 1289.83 XTY6 XTY7 4.53 991.90 XTY8 4.01 1145.97 XTY9 5.85 1398.65 XTY10 5.07 1189.76 XTY11 5.21 1237.91 XTY12 3.46 908.44 XTY13 3.73 965.83 XTY14 3.15 856.40 XTY15 5.13 1053.21 XTY16 3.78 892.54 XTY17 5.87 1027.39 XTY17a 5.69 1190.10

1.63 1.61 2.89 1.18 0.96 1.44 1.58 3.42 2.44 2.99 4.28 2.17 1.74 2.27 2.11 3.17 2.54 1.89 3.27 3.27 0.93 2.53 2.71 1.86

0.11 0.18 0.29 0.10 0.17 0.12 0.08 0.05 0.05 0.04 0.11 0.09 0.09 0.14 0.16 0.06 0.09 0.03 0.18 0.11 3.64 5.50 0.08 0.42 0.10 0.12 0.10 0.15 0.0098

2.62 2.58 7.95 2.50 2.87 2.66 2.81 2.81 2.64 2.82 3.02 2.64 2.48 2.36 3.02 2.67 7.65 2.93 6.01 2.87 2.82 5.98 2.97 6.82

2.38 12.00

8.89 5.49 7.50 11.30 8.74 7.49 7.16 5.39 5.27 6.00 6.31 9.25 9.41 13.24 18.95 8.03 10.16 10.12 10.63 12.01 6.59 8.38 3.45 4.43 0.67 0.31 0.51 7.93 1.50

La (ppm) 11.99

Ce (ppm) 17.79

Pr (ppm) 2.30

Nd (ppm) 8.47

21.57

35.68

4.52

16.44

23.94 18.49 30.51 23.82 24.24 14.75 14.15 13.00 19.04 15.41 15.46 18.88

41.35 31.78 52.77 42.21 42.10 24.52 23.07 20.19 32.99 25.28 27.67 32.99

5.29 4.07 6.68 5.63 5.33 3.20 2.98 2.47 4.43 3.23 3.80 4.13

20.35 16.03 24.35 20.82 19.81 12.68 12.23 9.25 17.22 12.38 15.26 16.13

359

3.53 5.50

XTY17b XTY17c XTY17d XTY17e XTY17f XTY18 XTY18a XTY18b XTY18c XTY18d XTY18e XTY19 XTY19a XTY19b XTY19c XTY19d XTY19e XTY19f XTY20 XTY21 XTY22 XTY23 XTY24 XTY25 XTY26 XTY27 XTY28 XTY29 XTY30 XTY31 XTY32 XTY33 Avg. BS UCC

5.94 5.36

1241.38 1253.34

22.56 20.92

38.78 36.07

4.98 4.65

19.05 17.54

5.99 6.47 5.98 4.98 15.07 5.02 5.47 4.73 5.65 5.58 5.46 5.55 5.34 5.31 4.90 5.37 5.52 6.03 10.93 5.22 4.30 5.77 4.37 7.64 4.47 3.82

1209.09 1142.63 1187.06 1105.06 1143.86 1170.41 1217.04 1153.75 1185.03 1265.83 1198.47 1237.51 1191.98 1093.85 1134.97 1085.03 1241.69 1207.50 2330.59 1178.76 922.76 1189.49 1117.96 1418.57 1076.32 871.60 529.00 394.90 551.03 1168.81 550.00

21.25 21.08 23.00 18.75 19.75 22.69 23.13 29.20 17.75 18.65 20.41 21.00 17.67 26.77 22.93 18.82 24.85 23.25 47.12 20.24 18.14 22.66 32.47 28.23 18.79 21.11

5.43 4.67 5.21 4.39 4.24 5.22 5.10 6.51 4.07 4.02 4.65 4.67 4.06 6.46 5.45 4.42 5.68 5.11 11.05 4.45 4.17 5.05 7.48 6.81 4.52 5.29

21.26 30.00

39.80 38.03 40.06 33.20 33.87 38.95 39.70 51.56 30.15 31.38 35.19 36.78 30.80 48.91 42.14 33.07 42.98 40.01 85.75 34.71 32.26 40.02 56.99 57.44 33.85 39.03 35.89 41.22 39.83 36.96 64.00

4.78 7.10

20.55 18.21 20.31 17.11 16.89 20.39 19.56 24.26 15.40 15.22 18.11 18.67 15.52 26.92 22.19 17.74 21.66 19.04 43.37 16.84 15.62 19.12 29.11 32.45 19.03 21.83 18.08 19.78 17.46 18.44 26.00

Gd (ppm) 1.36

Tb (ppm) 0.16

Dy (ppm) 0.96

Ho (ppm) 0.14

2.53

0.31

1.60

0.27

3.40 2.46 3.52 3.05 2.87 1.96 2.18

0.39 0.29 0.37 0.31 0.30 0.22 0.26

2.14 1.42 1.97 1.78 1.59 1.16 1.51

0.33 0.24 0.29 0.23 0.23 0.18 0.24

5.55 4.60

Xiaotan section, Sichuan Province Sample Sm (ppm) Eu (ppm) XTY1 1.84 0.49 XTY2 XTY3 XTY4 XTY5 3.10 0.80 XTY6 XTY7 4.04 0.89 XTY8 3.20 0.74 XTY9 4.63 1.08 XTY10 4.14 0.88 XTY11 3.86 0.91 XTY12 2.69 0.62 XTY13 2.71 0.68

360

XTY14 XTY15 XTY16 XTY17 XTY17a XTY17b XTY17c XTY17d XTY17e XTY17f XTY18 XTY18a XTY18b XTY18c XTY18d XTY18e XTY19 XTY19a XTY19b XTY19c XTY19d XTY19e XTY19f XTY20 XTY21 XTY22 XTY23 XTY24 XTY25 XTY26 XTY27 XTY28 XTY29 XTY30 XTY31 XTY32 XTY33 Avg. BS UCC

2.05 3.43 2.50 3.48 3.35 3.57 3.35

0.44 0.77 0.61 0.80 0.83 0.86 0.80

1.60 2.61 1.96 2.66 2.44 2.49 2.54

0.17 0.27 0.22 0.32 0.27 0.28 0.27

0.98 1.47 1.25 1.79 1.52 1.54 1.38

0.17 0.23 0.20 0.30 0.24 0.23 0.21

3.92 4.07 4.08 3.57 3.54 4.35 4.03 4.60 3.27 3.38 3.78 3.98 3.26 5.74 4.45 4.20 4.30 3.69 7.98 3.49 2.73 3.88 5.58 7.10 4.24 4.81

0.91 0.87 0.90 0.83 0.89 0.94 0.95 1.01 0.82 0.80 0.89 0.87 0.75 1.16 0.95 0.93 0.96 0.85 1.89 0.75 0.67 0.91 1.28 1.17 0.91 1.03

2.53 3.06 3.02 2.93 3.00 3.31 2.86 3.38 2.49 2.44 2.64 2.75 2.23 4.25 3.12 3.26 3.13 2.73 5.88 2.48 1.94 2.99 5.11 4.18 2.98 3.81

0.28 0.35 0.34 0.33 0.31 0.36 0.32 0.36 0.29 0.29 0.31 0.32 0.26 0.47 0.33 0.40 0.34 0.31 0.72 0.27 0.24 0.34 0.59 0.38 0.31 0.46

1.82 1.95 1.74 1.96 1.70 1.95 1.69 1.90 1.61 1.45 1.71 1.56 1.28 2.46 1.71 2.16 1.84 1.63 3.56 1.46 1.42 1.81 3.22 2.31 1.76 2.63

0.25 0.33 0.27 0.31 0.27 0.32 0.26 0.29 0.24 0.22 0.24 0.24 0.19 0.40 0.26 0.35 0.29 0.25 0.64 0.23 0.22 0.27 0.55 0.31 0.28 0.42

3.74 4.50

0.86 0.88

2.79 3.80

0.31 0.64

1.70 3.50

0.27 0.80

Yb (ppm) 0.30

Lu (ppm) 0.04

Hf (ppm) 0.10

Ta (ppm) 0.40

0.55

0.07

0.18

0.45

0.67 0.44

0.10 0.07

0.18 0.13

0.37 0.50

Xiaotan section, Sichuan Province Sample Er (ppm) Tm (ppm) XTY1 0.36 0.05 XTY2 XTY3 XTY4 XTY5 0.74 0.09 XTY6 XTY7 0.90 0.11 XTY8 0.59 0.08

361

XTY9 XTY10 XTY11 XTY12 XTY13 XTY14 XTY15 XTY16 XTY17 XTY17a XTY17b XTY17c XTY17d XTY17e XTY17f XTY18 XTY18a XTY18b XTY18c XTY18d XTY18e XTY19 XTY19a XTY19b XTY19c XTY19d XTY19e XTY19f XTY20 XTY21 XTY22 XTY23 XTY24 XTY25 XTY26 XTY27 XTY28 XTY29 XTY30 XTY31 XTY32 XTY33 Avg. BS UCC

0.74 0.64 0.57 0.47 0.61 0.41 0.60 0.51 0.79 0.62 0.62 0.54

0.09 0.10 0.08 0.06 0.08 0.06 0.08 0.06 0.11 0.08 0.08 0.07

0.49 0.42 0.45 0.40 0.47 0.37 0.46 0.38 0.66 0.49 0.50 0.43

0.07 0.06 0.06 0.06 0.07 0.05 0.06 0.05 0.11 0.07 0.07 0.06

0.25 0.21 0.15 0.12 0.13 0.18 0.16 0.15 0.16 0.21 0.25 0.18

0.52 0.45 0.65 0.46 0.52 0.62 0.57 0.42 0.68 0.36 0.59 0.30

0.66 0.92 0.67 0.81 0.73 0.81 0.67 0.72 0.64 0.58 0.63 0.60 0.50 1.07 0.67 0.84 0.80 0.67 1.54 0.62 0.48 0.76 1.33 1.13 0.72 1.04

0.09 0.12 0.08 0.10 0.08 0.12 0.09 0.10 0.09 0.07 0.09 0.08 0.06 0.14 0.08 0.11 0.10 0.09 0.21 0.07 0.07 0.10 0.18 0.41 0.10 0.14

0.50 0.69 0.46 0.63 0.51 0.63 0.51 0.57 0.50 0.43 0.50 0.49 0.39 0.83 0.54 0.65 0.63 0.54 1.16 0.53 0.44 0.59 0.96 0.51 0.63 0.84

0.06 0.11 0.08 0.10 0.08 0.10 0.07 0.08 0.08 0.07 0.08 0.06 0.05 0.13 0.07 0.09 0.10 0.07 0.17 0.08 0.06 0.08 0.16 0.05 0.10 0.14

0.45 0.66 0.48 0.33 0.72 0.30 0.29 0.42 0.37 0.34 0.58 0.55 0.47 0.80 0.50 0.34 0.43 0.49 1.41 0.43 0.52 0.55 0.46 0.58 0.51 0.39

0.69 2.30

0.09 0.33

0.53 2.20

0.08 0.32

0.19 0.42 0.19 0.15 0.18 0.18 0.17 0.19 0.18 0.17 0.20 0.18 0.18 0.21 0.19 0.15 0.24 0.21 0.54 0.14 0.16 0.21 0.21 0.22 0.21 0.18 1.30 1.85 1.85 0.19 5.80

Bi (ppm) 0.16

Th (ppm) 8.74

Xiaotan section, Sichuan Province Sample W (ppm) Pb (ppm) XTY1 53.91 33.11 XTY2 XTY3

362

U (ppm)

0.51 1.00

Mo/Sc 2.07

0.36

XTY4 XTY5 XTY6 XTY7 XTY8 XTY9 XTY10 XTY11 XTY12 XTY13 XTY14 XTY15 XTY16 XTY17 XTY17a XTY17b XTY17c XTY17d XTY17e XTY17f XTY18 XTY18a XTY18b XTY18c XTY18d XTY18e XTY19 XTY19a XTY19b XTY19c XTY19d XTY19e XTY19f XTY20 XTY21 XTY22 XTY23 XTY24 XTY25 XTY26 XTY27 XTY28 XTY29 XTY30 XTY31 XTY32 XTY33 Avg. BS UCC

71.66

21.88

0.13

10.39

2.34

0.08

70.88 93.37 65.47 53.20 79.42 57.41 55.80 66.66 142.93 68.64 84.49 103.57 70.11 62.34

19.38 28.40 45.66 38.90 52.53 19.91 17.96 13.81 33.67 25.65 37.29 40.19 28.58 32.73

0.12 0.23 0.25 0.19 0.26 0.10 0.10 0.09 0.26 0.13 0.23 0.40 0.24 0.26

10.01 9.72 14.66 12.69 11.66 6.71 7.92 5.42 8.55 8.28 9.38 9.64 9.37 8.92

1.82 1.29 6.11 5.32 5.02 1.35 1.44 1.55 3.55 2.11 3.95 4.53 3.59 2.82

0.07 0.10 0.65 0.59 0.62 0.17 0.12 0.28 0.37 0.74 0.33 0.28 0.26 0.24

71.95 99.64 100.33 65.52 96.32 66.76 81.10 74.15 78.21 224.81 66.65 63.40 51.95 106.27 77.60 113.39 77.60 81.41 269.89 86.92 103.35 85.75 114.84 96.45 76.55 108.30 1.02 1.09 1.06 87.97 2.00

36.92 61.94 42.77 41.76 50.83 50.23 46.96 46.93 44.78 33.75 49.74 52.50 55.61 56.61 51.14 55.58 58.02 37.40 148.04 49.92 38.71 58.19 60.68 42.44 43.25 27.78 5.18 4.01 3.79 43.63 17.00

0.24 0.39 0.30 0.24 0.32 0.33 0.32 0.31 0.31 0.52 0.34 0.32 0.28 0.37 0.31 0.27 0.38 0.32 1.04 0.34 0.26 0.46 0.35 0.55 0.32 0.22

8.24 11.99 10.79 8.07 8.86 10.30 9.96 10.55 9.18 8.76 10.14 9.76 8.52 9.98 10.36 8.64 10.38 9.54 25.94 9.89 8.39 10.38 10.96 9.63 9.72 12.04 6.31 7.15 7.28 10.02 10.70

2.58 4.04 4.09 3.39 3.43 5.15 4.31 5.09 4.92 3.69 4.06 4.31 3.26 5.93 5.75 5.58 8.37 5.30 10.63 3.88 3.48 3.95 4.79 3.19 3.64 3.62 1.46 1.64 1.41 4.05 2.80

0.21 0.10 0.42 0.27 0.26 0.53 0.41 0.36 0.34 0.24 0.26 0.27 0.30 0.43 0.45 0.63 0.83 0.38 0.38 0.62 0.34 0.54 0.37 0.05 0.17 0.16 0.08 0.04 0.06 0.36 0.11

0.29 0.00127

363

Xiaotan section, Sichuan Province Sample V/Sc U/Sc XTY1 7.31 XTY2 XTY3 XTY4 XTY5 5.80 XTY6 XTY7 5.76 XTY8 5.76 XTY9 5.25 XTY10 4.80 XTY11 8.97 XTY12 6.85 XTY13 6.97 XTY14 5.38 XTY15 7.99 XTY16 6.54 XTY17 9.07 XTY17a 9.02 XTY17b 7.03 XTY17c 7.22 XTY17d XTY17e 5.05 XTY17f 5.80 XTY18 7.59 XTY18a 7.06 XTY18b 5.40 XTY18c 12.88 XTY18d 11.58 XTY18e 10.82 XTY19 6.36 XTY19a 6.23 XTY19b 7.74 XTY19c 8.75 XTY19d 10.63 XTY19e 11.36 XTY19f 9.92 XTY20 8.73 XTY21 8.94 XTY22 7.78 XTY23 4.26 XTY24 6.42 XTY25 4.49 XTY26 8.04 XTY27 6.93 XTY28 1.22 XTY29 6.80 XTY30 4.69 XTY31 7.58

Mo/TOC (10-4)

V/TOC (10-4)

Th/U

V/(V+Ni)

0.15

2.16

44.29

4.22

0.85

0.12

1.03

76.84

4.44

0.81

0.11 0.08 0.24 0.17 0.24 0.09 0.08 0.06 0.19 0.14 0.21 0.22 0.17 0.13

1.18 1.19 10.59 14.37 6.58 1.28 1.09 3.71 3.68 5.01 3.30 2.76 3.24 2.59

93.83 67.27 85.64 117.58 95.76 51.62 64.14 72.35 79.23 44.29 91.88 89.70 89.46 77.22

5.50 7.50 2.40 2.39 2.32 4.97 5.50 3.49 2.41 3.93 2.37 2.13 2.61 3.17

0.80 0.82 0.91 0.88 0.92 0.80 0.80 0.82 0.83 0.61 0.84 0.87 0.85 0.84

0.10 0.08 0.20 0.16 0.12 0.24 0.20 0.24 0.23 0.17 0.20 0.19 0.16 0.27 0.27 0.27 0.37 0.25 0.39 0.24 0.11 0.18 0.27 0.02 0.18 0.13 0.18

2.81 2.71 4.31 3.14 3.49 5.16 4.14 3.54 3.30 2.74 2.51 2.87 4.63 4.42 4.30 6.43 8.78 4.32 5.30 4.69 5.23 5.35 4.29 3.72 7.35 12.13 3.40

67.99 154.43 77.26 83.09 72.47 124.56 117.53 107.17 61.99 70.61 75.98 94.67 163.12 118.09 95.11 88.92 94.42 89.50 60.01 48.56 68.87 80.20 79.48 100.33 299.50 349.19 315.24

3.19 2.97 2.64 2.38 2.58 2.00 2.31 2.07 1.87 2.38 2.50 2.26 2.61 1.68 1.80 1.55 1.24 1.80 2.44 2.55 2.41 2.63 2.29 3.01 2.67 3.33 4.32

0.83 0.85 0.85 0.79 0.84 0.91 0.89 0.86 0.86 0.88 0.87 0.89 0.93 0.80 0.90 0.83 0.88 0.87 0.82 0.88 0.85 0.83 0.30 0.29 0.83 0.74 0.73

364

XTY32 XTY33 Avg. BS UCC

8.39 7.81 7.51 7.87

0.24 0.17 0.19 0.21

Xiaotan section, Sichuan Province Sample Distance (m) Formation XTY35 83 Yuanshan XTY36 84 Yuanshan XTY37 84.6 Yuanshan XTY38 85.3 Yuanshan XTY39 86.3 Yuanshan XTY40 88.3 Yuanshan XTY41 90 Yuanshan XTY42 94 Yuanshan XTY43 97 Yuanshan XTY44 98.3 Yuanshan XTY45 99.3 Yuanshan XTY46 100.8 Yuanshan XTY47 101.7 Yuanshan XTY48 104.7 Yuanshan XTY49 106.7 Yuanshan XTY50 108.5 Yuanshan XTY51 110.5 Yuanshan XTY52 115 Yuanshan XTY53 120 Yuanshan XTY54 125 Yuanshan XTY55 130 Yuanshan XTY56 139 Yuanshan XTY57 149 Yuanshan XTY58 160 Yuanshan XTY59 175 Yuanshan XTY60 190 Yuanshan XTY61 200 Yuanshan Average in black shale Upper Continental Crust

1.09 3.93 4.16

204.59 502.53 85.68

4.35 5.16 2.87 3.82

Position: 28° 7'28.68"N, 103°27'58.96"E Lithology Si (%) Al (%) Black shale Black shale Black shale Black shale Black shale Black shale Black shale Shale Shale Shale Shale Carbonatic shale Shale Shale Shale Carbonatic shale Carbonatic shale Carbonatic shale Carbonatic shale Carbonatic shale Carbonatic shale Carbonatic shale Carbonatic shale Carbonatic shale Shale Shale Shale

365

0.74 0.74 0.85 0.71

Fe (%) 1.56 3.10 3.37 3.33 5.31 2.38 4.51 4.70 3.83 4.60 4.54 2.83 4.32 3.99 4.21 2.70 4.18 4.23 4.49 4.77 4.24 4.07 4.28 4.42 4.26 4.27 3.29 3.53 3.50

Xiaotan (high resolution sampling within the lower Shiyantou) Sample Distance (m) Formation Lithology XTS1 0 Shiyantou Black shale XTS2 0.17 Shiyantou Black shale XTS3 0.27 Shiyantou Black shale XTS4 0.38 Shiyantou Black shale XTS5 0.53 Shiyantou Black shale XTS6 0.63 Shiyantou Black shale XTS7 0.65 Shiyantou Black shale XTS8 0.66 Shiyantou Black shale XTS9 0.68 Shiyantou Black shale XTS10 0.7 Shiyantou Black shale XTS11 0.8 Shiyantou Black shale XTS12 0.89 Shiyantou Black shale XTS13 1.01 Shiyantou Black shale XTS14 1.19 Shiyantou Black shale Upper Continental Crust Xiaotan section, Sichuan Province Sample Mg (%) Ca (%) XTY35 XTY36 XTY37 XTY38 XTY39 XTY40 XTY41 XTY42 XTY43 XTY44 XTY45 XTY46 XTY47 XTY48 XTY49 XTY50 XTY51 XTY52 XTY53 XTY54 XTY55 XTY56 XTY57 XTY58 XTY59 XTY60 XTY61 Avg. BS UCC

Na (%)

K (%)

Si (%)

Al (%)

Fe (%) 1.28 1.25 1.22 1.41 1.40 1.73 2.01 2.69 1.94 2.61 1.56 1.46 0.81 1.49 3.50

P (%)

TC (%) 4.80 4.02 3.38 3.21 1.94 6.67 2.05 1.07 1.73 1.22 1.11 5.49 1.66 2.44 1.32 6.91 1.51 1.77 1.55 1.16 1.88 2.76 1.06 1.48 1.84 1.59 3.40 3.39

366

Xiaotan (high resolution sampling within the lower Shiyantou) Sample Mg (%) Ca (%) Na (%) K (%) XTS1 XTS2 XTS3 XTS4 XTS5 XTS6 XTS7 XTS8 XTS9 XTS10 XTS11 XTS12 XTS13 XTS14 UCC Xiaotan section, Sichuan Province Sample TS (%) TOC (%) XTY35 0.16 XTY36 0.05 XTY37 0.15 XTY38 0.05 XTY39 0.04 XTY40 0.08 XTY41 0.34 XTY42 0.67 XTY43 0.12 XTY44 0.04 XTY45 0.47 XTY46 0.43 XTY47 1.13 XTY48 0.67 XTY49 0.94 XTY50 0.63 XTY51 1.02 XTY52 1.05 XTY53 1.16 XTY54 0.81 XTY55 0.41 XTY56 0.44 XTY57 0.03 XTY58 0.46 XTY59 0.01 XTY60 0.12 XTY61 0.04 Avg. BS 0.19 UCC

4.74 4.00 3.32 3.16 1.86 0.52 0.84 1.00 0.71 0.75 0.72 0.16 0.47 0.47 0.31 0.13 0.30 0.32 0.33 0.28 0.21 0.25 0.20 0.21 0.15 0.17 0.13 2.43

Pyrite S (%) 0.07 0.01 0.09 0.01 0.00 0.06 0.17 0.13 0.10 0.03 0.23 0.19 0.09 0.22 0.20 0.20 0.84 0.84 0.91 0.68 0.35 0.39 0.03 0.38 0.01 0.11 0.02 0.07

367

P (%)

TC (%) 3.22 2.93 3.12 5.07 3.26 3.04 2.91 3.10 3.12 3.03 2.50 3.10 3.55 3.91

34

δ S pyrite

3.09

-2.16 -9.02 -4.31 -6.63 -8.27 1.49 -5.00 -6.61 -6.42 12.65 -9.90 -8.35 -7.03 -4.41 -3.41 -7.71 -6.29 4.66 -2.70

Li (ppm) 24.68 39.75 38.08 50.23 51.86 28.06 38.71 51.31 41.88 53.06 50.03 26.20 47.17 42.33 45.13 27.19 47.96 44.90 46.11 49.43 45.63 41.23 46.75 48.41 48.79 48.38 40.87 40.34 20.00

Be (ppm) 2.45 2.21 2.39 3.34 3.04 1.44 1.77 2.61 2.31 2.54 2.48 1.06 2.44 1.88 2.04 1.15 2.37 4.08 2.30 2.19 2.15 1.84 2.45 2.12 2.10 2.25 1.47 2.41 3.00

Xiaotan (high resolution sampling within the lower Shiyantou) 34 Sample TS (%) TOC (%) Pyrite S (%) δ S pyrite XTS1 0.07 3.16 0.00 XTS2 0.12 2.86 0.01 XTS3 0.08 3.03 0.01 XTS4 0.09 4.74 0.00 XTS5 0.05 3.18 0.00 XTS6 0.15 3.01 0.00 XTS7 0.10 2.92 0.00 XTS8 0.19 3.07 0.00 XTS9 0.29 3.13 0.01 XTS10 0.17 3.00 0.00 XTS11 0.39 2.53 0.01 XTS12 0.16 3.13 0.00 XTS13 0.14 3.60 0.01 XTS14 0.22 3.89 0.01 UCC

Li (ppm) 25.39 26.76 21.63 33.22 29.48 25.54 33.53 27.26 21.75 24.38 17.71 20.20 24.42 25.41 20.00

Be (ppm) 1.42 1.94 1.65 2.00 1.38 1.47 1.57 1.46 1.43 1.40 1.32 1.17 1.87 1.83 3.00

Xiaotan section, Sichuan Province Sample Sc (ppm) Ti (ppm) XTY35 26.04 2962.69 XTY36 26.19 2756.31 XTY37 27.49 2910.50 XTY38 43.18 2664.31 XTY39 43.75 2586.89 XTY40 14.87 1830.93 XTY41 20.59 1554.09 XTY42 26.45 2810.08 XTY43 21.55 2597.60 XTY44 25.50 2787.19 XTY45 25.39 2922.27 XTY46 13.33 1547.61 XTY47 22.83 3934.73 XTY48 16.13 3836.87 XTY49 16.72 3721.73 XTY50 14.05 1450.62 XTY51 21.64 2129.84 XTY52 35.61 2298.18 XTY53 22.22 2227.28 XTY54 22.74 2135.37 XTY55 21.02 2103.52 XTY56 18.01 1909.57 XTY57 23.75 2435.77 XTY58 20.40 2241.83 XTY59 21.15 2640.02 XTY60 21.91 2490.96 XTY61 15.10 1431.53 Avg. BS 28.57 2509.47 UCC 13.60 4100.00

Mn (ppm) 88.77 135.27 127.10 200.17 204.74 2602.38 1269.42 233.96 486.64 380.46 380.11 2805.04 609.02 668.79 432.67 2330.33 576.27 669.80 616.90 520.18 705.20 1114.88 520.92 664.97 780.16 604.29 964.10 607.73 600.00

Co (ppm) 18.37 15.86 19.38 26.89 27.00 29.11 20.30 17.43 30.74 21.17 22.51 18.36 23.40 17.50 20.70 22.59 21.29 22.17 25.71 22.39 27.57 26.53 19.61 30.81 22.45 22.89 25.44 21.79 17.00

V (ppm) 458.57 660.59 592.07 524.88 501.15 343.80 272.80 355.68 423.80 482.68 372.40 147.66 337.79 263.67 222.60 148.83 276.26 287.80 266.90 244.23 244.85 188.13 293.71 258.76 242.16 271.66 152.91 463.69 107.00

368

Cr (ppm) 114.10 125.15 130.88 181.30 173.19 79.40 98.78 122.48 109.80 128.40 123.06 55.74 117.95 85.10 88.41 65.88 111.24 148.97 109.29 107.28 103.66 87.97 118.78 97.82 113.14 107.81 73.08 128.16 83.00

Xiaotan (high resolution sampling within the lower Shiyantou) Sample Sc (ppm) Ti (ppm) V (ppm) Cr (ppm) XTS1 12.56 1595.23 407.90 225.09 XTS2 16.06 2361.79 513.44 227.19 XTS3 16.72 2390.29 572.21 210.26 XTS4 15.42 1756.32 1574.75 504.44 XTS5 19.42 1464.87 612.38 286.39 XTS6 13.40 1748.09 457.91 228.70 XTS7 13.52 2079.26 461.62 256.92 XTS8 12.95 1803.75 474.98 245.27 XTS9 13.89 1871.50 495.36 231.66 XTS10 13.32 1389.78 459.33 213.09 XTS11 16.31 2377.64 511.10 168.07 XTS12 11.11 1045.31 422.85 129.28 XTS13 16.01 2243.60 1347.70 278.95 XTS14 14.68 1989.19 1443.56 364.66 UCC 13.60 4100.00 107.00 83.00

Mn (ppm) 83.76 47.88 36.73 74.22 266.54 63.25 122.12 80.35 61.80 90.19 19.83 50.65 35.18 39.44 600.00

Co (ppm) 20.39 19.24 31.11 20.96 17.73 24.63 21.97 29.41 30.97 35.37 34.70 35.16 35.86 25.86 17.00

Xiaotan section, Sichuan Province Sample Ni (ppm) Cu (ppm) XTY35 22.16 16.15 XTY36 63.02 17.88 XTY37 65.48 21.02 XTY38 72.37 22.62 XTY39 71.63 27.49 XTY40 51.15 19.38 XTY41 39.91 15.69 XTY42 59.57 28.65 XTY43 60.47 31.45 XTY44 68.83 34.84 XTY45 64.19 25.20 XTY46 38.69 13.17 XTY47 72.18 30.11 XTY48 57.13 19.23 XTY49 55.98 18.58 XTY50 47.05 15.54 XTY51 56.66 25.41 XTY52 62.76 29.95 XTY53 61.74 30.43 XTY54 57.71 24.88 XTY55 56.76 25.04 XTY56 49.87 15.46 XTY57 63.91 24.09 XTY58 62.24 12.77 XTY59 66.90 46.50 XTY60 57.44 17.71 XTY61 44.34 18.12 Avg. BS 55.66 21.11 UCC 44.00 25.00

Rb (ppm) 195.09 182.11 187.05 208.44 161.98 94.19 102.36 192.24 144.63 171.40 178.16 73.16 173.17 113.45 129.90 76.60 160.31 144.80 154.18 155.40 139.44 114.33 161.89 146.41 135.71 147.44 85.16 165.43 112.00

Sr (ppm) 39.78 36.92 38.85 54.33 50.90 470.43 263.63 41.96 124.28 77.87 82.07 467.69 159.86 197.12 122.10 569.20 152.29 167.27 151.12 108.34 179.33 263.96 120.27 147.31 163.79 132.14 222.30 124.60 350.00

Zn (ppm) 100.18 112.88 117.68 141.97 125.71 135.20 109.99 108.00 120.55 132.67 161.45 66.80 109.04 73.00 99.87 108.58 117.71 118.07 136.62 104.54 145.72 141.35 107.19 88.18 140.15 110.75 98.67 118.95 71.00

369

Ga (ppm) 29.65 28.65 29.99 29.65 28.62 17.41 18.13 30.35 23.53 28.52 29.00 14.00 27.06 19.44 22.18 14.89 26.46 24.55 24.96 26.44 24.17 20.80 27.12 24.52 24.73 25.65 17.23 26.56 17.00

Xiaotan (high resolution sampling within the lower Shiyantou) Sample Ni (ppm) Cu (ppm) Zn (ppm) Ga (ppm) XTS1 25.47 13.56 70.19 16.28 XTS2 28.11 10.78 112.68 18.96 XTS3 18.88 6.56 60.93 18.59 XTS4 44.38 27.91 108.47 18.75 XTS5 31.56 13.18 107.78 16.89 XTS6 55.62 18.51 85.26 15.53 XTS7 58.32 33.05 139.06 16.06 XTS8 43.32 31.76 124.81 15.33 XTS9 40.68 17.47 99.77 15.69 XTS10 47.13 34.01 78.37 14.70 XTS11 3.45 6.33 44.27 15.32 XTS12 35.83 12.33 77.28 12.74 XTS13 23.61 7.97 81.38 20.35 XTS14 35.59 16.09 113.45 17.94 UCC 44.00 25.00 71.00 17.00

Rb (ppm) 100.97 124.66 123.66 127.85 102.72 97.49 99.34 94.23 101.84 92.50 115.97 75.79 139.28 120.14 112.00

Sr (ppm) 111.23 110.26 130.88 86.65 109.91 73.32 80.00 97.37 104.06 73.58 80.11 127.27 66.37 122.37 350.00

Xiaotan section, Sichuan Province Sample Y (ppm) Zr (ppm) XTY35 3.70 6.40 XTY36 5.28 7.05 XTY37 5.96 8.55 XTY38 6.99 8.90 XTY39 6.09 8.91 XTY40 13.24 6.51 XTY41 11.59 6.66 XTY42 12.22 9.05 XTY43 16.78 9.30 XTY44 15.63 9.43 XTY45 12.80 9.13 XTY46 20.73 6.56 XTY47 14.03 11.91 XTY48 27.61 137.75 XTY49 26.86 147.81 XTY50 21.66 6.13 XTY51 13.81 7.33 XTY52 13.34 7.04 XTY53 13.70 7.96 XTY54 10.91 7.41 XTY55 14.06 7.39 XTY56 23.92 6.63 XTY57 13.38 8.34 XTY58 14.45 7.65 XTY59 14.33 8.10 XTY60 12.22 8.00 XTY61 16.42 6.60 Avg. BS 8.13 7.75 UCC 22.00 190.00

Cd (ppm) 0.14 0.15 0.18 0.31 0.16 0.41 0.47 0.13 0.68 0.62 0.48 0.25 0.49 0.54 0.41 0.47 0.31 0.45 0.74 0.34 0.55 0.68 0.43 0.32 0.45 0.31 0.45 0.24 0.0098

Sn (ppm) 4.00 3.63 3.75 11.21 17.94 2.31 7.75 3.68 3.10 3.81 3.70 1.77 3.56 2.39 2.96 1.76 3.41 10.87 3.10 3.38 3.05 2.57 3.57 3.04 3.30 3.44 2.10 6.78 5.50

Nb (ppm) 6.21 5.60 5.88 5.97 6.23 4.32 4.98 5.51 5.16 5.65 6.16 3.39 9.40 10.47 10.65 3.15 3.86 4.04 4.10 3.79 4.25 3.75 4.81 4.65 5.85 5.12 0.74 5.59 12.00

370

Mo (ppm) 39.24 36.78 29.12 26.38 15.15 4.68 7.32 6.09 6.56 5.35 12.39 1.59 2.93 5.01 2.86 2.76 2.64 3.46 2.00 0.59 1.52 1.31 0.59 0.89 0.71 1.17 0.35 20.60 1.50

Xiaotan (high resolution sampling within the lower Shiyantou) Sample Y (ppm) Zr (ppm) Nb (ppm) Mo (ppm) XTS1 27.76 7.43 3.02 3.41 XTS2 22.77 10.08 4.61 6.27 XTS3 26.03 9.04 4.01 5.87 XTS4 29.38 7.96 3.31 6.11 XTS5 29.46 8.86 4.49 7.23 XTS6 16.66 7.35 3.02 5.46 XTS7 28.09 9.08 3.06 6.01 XTS8 22.24 8.42 1.71 5.07 XTS9 18.40 8.48 3.95 8.36 XTS10 20.42 6.33 1.39 6.05 XTS11 2.01 9.10 3.34 14.53 XTS12 39.60 5.12 0.78 6.28 XTS13 9.18 9.20 3.04 10.55 XTS14 45.95 7.83 4.79 7.79 UCC 22.00 190.00 12.00 1.50

Cd (ppm) 0.20 0.30 0.18 0.93 0.64 0.23 0.40 0.30 0.44 0.57 0.03 0.27 0.14 0.27 0.0098

Sn (ppm) 2.39 2.80 2.74 2.96 6.34 2.19 2.37 2.27 2.69 2.35 2.81 2.01 2.90 2.57 5.50

Xiaotan section, Sichuan Province Sample Cs (ppm) Ba (ppm) XTY35 7.55 1484.48 XTY36 8.26 1358.76 XTY37 9.55 1408.71 XTY38 6.69 1127.62 XTY39 10.36 1630.51 XTY40 6.06 865.45 XTY41 6.68 979.89 XTY42 10.23 1475.02 XTY43 8.03 1229.27 XTY44 8.92 1310.75 XTY45 8.95 1339.44 XTY46 4.52 644.58 XTY47 9.25 1311.46 XTY48 5.51 918.53 XTY49 13.25 1039.05 XTY50 12.44 679.84 XTY51 9.04 1244.00 XTY52 10.33 1422.89 XTY53 8.34 1178.69 XTY54 8.37 1190.40 XTY55 7.40 1110.63 XTY56 7.50 869.08 XTY57 9.17 1225.63 XTY58 7.96 1061.59 XTY59 7.22 1014.35 XTY60 7.49 1077.83 XTY61 4.53 691.15 Avg. BS 8.17 1291.31 UCC 4.60 550.00

Pr (ppm) 4.23 3.78 3.96 3.53 4.79 4.90 5.51 4.47 6.13 5.58 5.12 5.22 5.82 7.20 8.07 5.24 3.96 5.12 4.40 3.71 5.03 5.82 4.32 4.13 5.21 4.69 6.04 4.40 7.10

Nd (ppm) 15.94 14.63 14.50 13.03 18.81 20.07 22.05 18.90 26.65 24.05 21.16 22.45 23.27 29.34 30.45 21.79 17.70 24.93 18.79 15.52 21.23 27.41 18.76 18.00 21.37 19.31 23.51 17.24 26.00

La (ppm) 20.09 16.77 18.57 14.91 22.18 20.02 23.61 18.05 23.50 22.14 20.84 21.60 23.75 30.38 36.81 20.30 14.56 19.28 17.11 14.35 21.26 20.85 17.72 15.71 20.21 19.41 26.77 19.27 30.00

371

Ce (ppm) 34.79 28.16 30.91 26.92 37.37 36.90 43.01 32.68 45.01 41.79 38.40 37.85 43.52 57.18 69.28 37.62 27.69 36.42 32.46 27.13 38.67 41.01 32.53 30.05 39.41 36.23 49.48 33.84 64.00

Xiaotan (high resolution sampling within the lower Shiyantou) Sample Cs (ppm) Ba (ppm) La (ppm) Ce (ppm) XTS1 4.83 914.59 17.47 27.95 XTS2 5.84 1176.50 17.51 26.70 XTS3 5.55 1174.78 25.33 41.32 XTS4 6.52 1112.37 19.82 30.69 XTS5 5.72 973.76 20.22 34.40 XTS6 4.66 822.86 15.75 22.38 XTS7 4.76 866.24 19.21 31.70 XTS8 5.85 855.92 23.24 35.37 XTS9 4.29 911.52 19.08 28.85 XTS10 5.34 799.81 13.79 20.90 XTS11 4.30 1213.12 8.71 7.94 XTS12 3.60 658.62 28.46 51.13 XTS13 6.51 1167.78 18.26 23.06 XTS14 5.75 1027.38 30.47 54.80 UCC 4.60 550.00 30.00 64.00

Pr (ppm) 4.97 4.57 7.00 5.53 5.60 3.68 5.16 5.58 4.74 3.56 1.09 8.50 3.47 10.06 7.10

Nd (ppm) 20.69 19.42 29.98 22.75 23.28 14.07 20.90 21.55 18.33 15.56 3.06 36.22 12.95 42.93 26.00

Xiaotan section, Sichuan Province Sample Sm (ppm) Eu (ppm) XTY35 2.89 0.61 XTY36 3.02 0.65 XTY37 3.00 0.65 XTY38 2.31 0.48 XTY39 3.32 0.73 XTY40 4.35 1.07 XTY41 4.93 1.29 XTY42 4.22 1.01 XTY43 6.19 1.37 XTY44 5.61 1.40 XTY45 4.84 1.14 XTY46 5.19 1.24 XTY47 4.98 1.21 XTY48 6.28 1.39 XTY49 5.28 1.23 XTY50 5.33 1.31 XTY51 4.60 1.12 XTY52 6.10 1.49 XTY53 4.54 1.12 XTY54 3.85 0.89 XTY55 4.90 1.13 XTY56 7.66 1.91 XTY57 4.74 1.07 XTY58 4.53 1.16 XTY59 4.95 1.18 XTY60 4.42 1.08 XTY61 5.01 1.20 Avg. BS 3.50 0.81 UCC 4.50 0.88

Dy (ppm) 1.17 1.50 1.61 3.61 1.99 2.92 2.64 2.94 3.96 3.85 3.13 4.00 3.22 5.19 4.82 4.21 3.15 4.00 3.17 2.62 3.21 5.16 3.13 3.38 3.20 2.88 3.54 2.30 3.50

Ho (ppm) 0.17 0.25 0.26 0.67 0.30 0.49 0.44 0.50 0.65 0.64 0.51 0.71 0.55 1.01 0.99 0.75 0.53 0.64 0.55 0.44 0.55 0.84 0.52 0.55 0.57 0.49 0.61 0.38 0.80

Gd (ppm) 1.93 2.35 2.33 2.39 2.57 3.82 4.22 3.84 5.51 5.18 4.37 4.93 4.50 5.91 5.01 5.09 4.39 5.73 4.48 3.67 4.47 7.52 4.36 4.57 4.65 4.02 4.86 2.93 3.80

372

Tb (ppm) 0.22 0.28 0.28 0.51 0.37 0.48 0.51 0.49 0.68 0.62 0.53 0.64 0.55 0.76 0.70 0.67 0.55 0.71 0.56 0.43 0.55 0.91 0.55 0.56 0.56 0.49 0.59 0.39 0.64

Xiaotan (high resolution sampling within the lower Shiyantou) Sample Sm (ppm) Eu (ppm) Gd (ppm) Tb (ppm) XTS1 4.27 1.01 4.61 0.60 XTS2 4.15 0.90 4.10 0.51 XTS3 5.94 1.34 5.60 0.73 XTS4 4.73 1.06 4.87 0.63 XTS5 4.74 1.12 5.25 0.69 XTS6 2.80 0.63 2.83 0.38 XTS7 4.34 0.94 4.53 0.59 XTS8 3.94 0.85 3.88 0.47 XTS9 3.61 0.73 3.31 0.42 XTS10 3.10 0.73 3.30 0.45 XTS11 0.38 0.20 0.29 0.04 XTS12 7.34 1.42 7.46 0.95 XTS13 2.63 0.59 2.45 0.29 XTS14 9.32 1.86 8.91 1.13 UCC 4.50 0.88 3.80 0.64

Dy (ppm) 3.97 3.46 4.52 4.23 4.78 2.39 3.89 3.27 2.74 2.87 0.29 5.81 1.89 6.96 3.50

Ho (ppm) 0.78 0.66 0.81 0.80 0.83 0.51 0.79 0.62 0.52 0.60 0.06 1.13 0.33 1.27 0.80

Xiaotan section, Sichuan Province Sample Er (ppm) Tm (ppm) XTY35 0.51 0.06 XTY36 0.61 0.09 XTY37 0.70 0.10 XTY38 1.80 0.27 XTY39 0.81 0.09 XTY40 1.27 0.17 XTY41 1.12 0.14 XTY42 1.28 0.16 XTY43 1.61 0.20 XTY44 1.62 0.20 XTY45 1.30 0.17 XTY46 1.93 0.25 XTY47 1.39 0.18 XTY48 3.21 0.42 XTY49 3.04 0.45 XTY50 2.09 0.28 XTY51 1.37 0.17 XTY52 1.74 0.21 XTY53 1.36 0.15 XTY54 1.10 0.14 XTY55 1.44 0.18 XTY56 2.07 0.24 XTY57 1.31 0.16 XTY58 1.35 0.18 XTY59 1.44 0.19 XTY60 1.25 0.15 XTY61 1.63 0.22 Avg. BS 1.01 0.14 UCC 2.30 0.33

Hf (ppm) 0.21 0.28 0.29 1.15 0.34 0.20 0.21 0.34 0.33 0.40 0.35 0.21 0.45 3.47 3.57 0.16 0.30 0.33 0.29 0.27 0.24 0.21 0.31 0.32 0.27 0.30 0.20 0.38 5.80

Ta (ppm) 0.59 0.58 0.61 1.78 0.54 0.51 0.59 0.61 0.66 0.60 0.67 0.40 0.83 0.91 1.19 0.38 0.33 0.50 0.41 0.34 0.42 0.32 0.43 0.64 0.49 0.60 0.23 0.72 1.00

Yb (ppm) 0.37 0.49 0.62 1.59 0.69 0.99 0.84 0.92 1.19 1.15 0.93 1.55 1.10 2.67 2.86 1.71 0.94 1.17 0.98 0.84 1.02 1.23 0.93 0.88 1.12 0.93 1.29 0.81 2.20

373

Lu (ppm) 0.05 0.08 0.10 0.23 0.09 0.16 0.10 0.14 0.18 0.19 0.14 0.28 0.19 0.45 0.44 0.28 0.15 0.17 0.14 0.13 0.15 0.19 0.15 0.13 0.17 0.16 0.19 0.12 0.32

Xiaotan (high resolution sampling within the lower Shiyantou) Sample Er (ppm) Tm (ppm) Yb (ppm) Lu (ppm) XTS1 2.11 0.25 1.31 0.19 XTS2 1.83 0.22 1.14 0.19 XTS3 2.08 0.25 1.19 0.15 XTS4 2.17 0.27 1.44 0.20 XTS5 2.36 0.29 1.43 0.17 XTS6 1.45 0.18 1.11 0.17 XTS7 2.19 0.28 1.51 0.25 XTS8 1.80 0.22 1.28 0.22 XTS9 1.45 0.19 1.11 0.16 XTS10 1.62 0.21 1.22 0.19 XTS11 0.18 0.03 0.19 0.02 XTS12 2.98 0.34 1.71 0.25 XTS13 0.94 0.12 0.65 0.09 XTS14 3.27 0.37 1.79 0.23 UCC 2.30 0.33 2.20 0.32

Hf (ppm) 0.26 0.43 0.35 0.25 0.30 0.27 0.31 0.31 0.30 0.21 0.38 0.16 0.29 0.30 5.80

Ta (ppm) 0.38 0.58 0.46 0.26 0.52 0.39 0.32 0.28 0.58 0.19 0.37 0.16 0.25 0.41 1.00

Xiaotan section, Sichuan Province Sample W (ppm) Pb (ppm) XTY35 47.59 81.13 XTY36 31.84 45.99 XTY37 38.82 57.77 XTY38 169.02 130.96 XTY39 92.48 40.23 XTY40 50.92 23.53 XTY41 54.18 20.76 XTY42 24.62 31.88 XTY43 64.10 24.57 XTY44 43.44 27.20 XTY45 40.03 28.00 XTY46 30.36 13.21 XTY47 119.75 30.47 XTY48 24.94 15.41 XTY49 31.02 16.41 XTY50 42.58 17.37 XTY51 35.69 21.61 XTY52 62.69 29.39 XTY53 28.31 31.08 XTY54 13.90 13.72 XTY55 42.88 11.33 XTY56 45.09 12.15 XTY57 25.21 8.03 XTY58 51.76 10.95 XTY59 33.08 6.24 XTY60 31.14 7.65 XTY61 60.46 6.02 Avg. BS 63.68 54.03 UCC 2.00 17.00

U (ppm) 12.19 8.87 8.07 26.10 4.96 3.57 2.93 3.68 4.03 3.84 3.79 3.84 3.84 5.79 4.88 2.00 3.77 3.24 1.11 0.95 1.43 1.20 1.00 1.10 1.15 1.33 0.65 8.80 2.80

Mo/Sc

Bi (ppm) 0.56 0.62 0.56 1.81 0.44 0.28 0.25 0.41 0.33 0.36 0.42 0.15 0.78 0.21 0.27 0.26 0.32 0.34 0.33 0.42 0.33 0.33 0.46 0.47 0.34 0.43 0.28 0.61 0.00127

374

Th (ppm) 9.83 9.70 10.14 29.29 7.09 6.79 5.38 8.39 7.41 9.38 9.10 3.91 8.56 9.30 11.32 4.28 8.18 8.05 5.72 6.13 6.57 6.35 6.07 6.60 6.25 7.21 4.18 10.83 10.70

1.51 1.40 1.06 0.61 0.35 0.32 0.36 0.23 0.30 0.21 0.49 0.12 0.13 0.31 0.17 0.20 0.12 0.10 0.09 0.03 0.07 0.07 0.02 0.04 0.03 0.05 0.02 0.72 0.11

Xiaotan (high resolution sampling within the lower Shiyantou) Sample W (ppm) Pb (ppm) Bi (ppm) Th (ppm) XTS1 82.13 10.42 0.21 5.98 XTS2 76.29 18.72 0.42 7.70 XTS3 74.85 19.77 0.37 6.49 XTS4 53.10 8.19 0.16 5.84 XTS5 92.08 13.95 0.21 6.21 XTS6 56.66 19.23 0.23 5.48 XTS7 59.31 17.01 0.21 5.55 XTS8 93.47 18.24 0.23 6.26 XTS9 72.58 26.27 0.28 6.00 XTS10 56.54 24.20 0.25 5.02 XTS11 60.16 29.38 0.22 5.59 XTS12 61.30 20.15 0.21 4.99 XTS13 51.70 13.23 0.35 7.12 XTS14 71.40 16.83 0.34 7.93 UCC 2.00 17.00 0.00127 10.70 Xiaotan section, Sichuan Province Sample V/Sc U/Sc XTY35 17.61 0.47 XTY36 25.23 0.34 XTY37 21.54 0.29 XTY38 12.16 0.60 XTY39 11.46 0.11 XTY40 23.12 0.24 XTY41 13.25 0.14 XTY42 13.45 0.14 XTY43 19.66 0.19 XTY44 18.93 0.15 XTY45 14.67 0.15 XTY46 11.08 0.29 XTY47 14.80 0.17 XTY48 16.35 0.36 XTY49 13.31 0.29 XTY50 10.59 0.14 XTY51 12.77 0.17 XTY52 8.08 0.09 XTY53 12.01 0.05 XTY54 10.74 0.04 XTY55 11.65 0.07 XTY56 10.44 0.07 XTY57 12.37 0.04 XTY58 12.69 0.05 XTY59 11.45 0.05 XTY60 12.40 0.06 XTY61 10.13 0.04 Avg. BS 16.23 0.31 UCC 7.87 0.21

Mo/TOC (10-4)

8.27 9.19 8.76 8.36 8.13 8.98 8.69 6.09 9.20 7.17 17.16 10.01 6.20 10.60 9.31 20.49 8.85 10.77 5.98 2.09 7.11 5.32 3.00 4.27 4.88 6.99 2.82 8.47

375

V/TOC (10-4)

96.66 165.06 178.12 166.26 268.86 659.00 323.65 355.32 594.31 646.07 516.01 931.64 714.14 557.56 724.14 1106.52 924.89 896.58 797.91 861.18 1145.25 761.67 1493.96 1239.78 1663.90 1619.58 1222.05 190.66

U (ppm)

Mo/Sc

6.99 7.89 7.34 11.72 9.00 5.05 5.45 6.34 5.50 5.34 3.27 9.06 8.72 28.14 2.80

Th/U

0.27 0.39 0.35 0.40 0.37 0.41 0.44 0.39 0.60 0.45 0.89 0.57 0.66 0.53 0.11

V/(V+Ni)

0.81 1.09 1.26 1.12 1.43 1.90 1.83 2.28 1.84 2.44 2.40 1.02 2.23 1.61 2.32 2.14 2.17 2.49 5.16 6.45 4.59 5.27 6.08 6.00 5.42 5.40 6.39 1.46 3.82

0.95 0.91 0.90 0.88 0.87 0.87 0.87 0.86 0.88 0.88 0.85 0.79 0.82 0.82 0.80 0.76 0.83 0.82 0.81 0.81 0.81 0.79 0.82 0.81 0.78 0.83 0.78 0.89 0.71

Xiaotan (high resolution sampling within the lower Shiyantou) Sample V/Sc U/Sc Mo/TOC (10-4) V/TOC (10-4) XTS1 32.46 0.56 1.08 129.06 XTS2 31.97 0.49 2.19 179.63 XTS3 34.22 0.44 1.94 189.02 XTS4 102.14 0.76 1.29 332.34 XTS5 31.53 0.46 2.28 192.75 XTS6 34.18 0.38 1.81 151.93 XTS7 34.14 0.40 2.06 158.31 XTS8 36.69 0.49 1.65 154.97 XTS9 35.67 0.40 2.67 158.36 XTS10 34.49 0.40 2.02 153.26 XTS11 31.33 0.20 5.73 201.78 XTS12 38.08 0.82 2.01 135.01 XTS13 84.18 0.54 2.93 374.57 XTS14 98.32 1.92 2.00 370.90 UCC 7.87 0.21

Th/U

V/(V+Ni)

0.86 0.98 0.88 0.50 0.69 1.09 1.02 0.99 1.09 0.94 1.71 0.55 0.82 0.28 3.82

Deze section, Yunnan Province Sample Distance (m) Formation DZ0 0 Dahai DZ1 0.3 Dahai DZ2 1.3 Dahai DZ3 2.5 Dahai DZ4 3.7 Dahai DZ5 5.2 Dahai DZ6 5.7 Dahai DZ7 6.9 Dahai Upper Continental Crust

Position: N 25°59'50", E 103°35'37" Lithology Si (%) Al (%) Limestone Limestone Limestone Limestone Limestone Limestone Limestone Limestone

Meishucun section, Yunnan Province Sample Distance (m) Formation KY1 0 Shiyantou KY2 1.5 Shiyantou KY3 3.5 Shiyantou KY4 5 Shiyantou KY5 7 Shiyantou KY6 8.5 Shiyantou KY7 10.5 Shiyantou KY8 12.5 Shiyantou KY9 13 Shiyantou KY10 13.5 BND Shi-Yu KY11 13.8 BND Shi-Yu UCC

Position: 24°43'51.46"N, 102°33'58.62"E Lithology Si (%) Al (%) Black shale 16.71 3.52 Black shale 25.79 6.18 Black shale 24.99 6.34 Black shale 24.82 6.64 Black shale 22.15 6.58 Black shale 25.15 7.08 Black shale 23.50 7.12 Black shale 22.29 6.59 Black shale 24.30 7.00 Phosphorite 7.99 1.90 Phosphorite 8.90 2.14 30.80 8.04

376

0.94 0.95 0.97 0.97 0.95 0.89 0.89 0.92 0.92 0.91 0.99 0.92 0.98 0.98 0.71

Fe (%) 0.531809145 0.541211519 0.995049505 1.642156863 1.130478088 0.554994955 1.034136546 1.282178218 3.50

Fe (%) 2.24 2.37 2.35 2.86 2.81 3.52 3.09 2.84 3.13 3.31 1.63 3.50

Deze section, Yunnan Province Sample Mg (%) Ca (%) DZ0 DZ1 DZ2 DZ3 DZ4 DZ5 DZ6 DZ7 UCC

Meishucun section, Yunnan Province Sample Mg (%) Ca (%) KY1 4.75 4.75 KY2 2.13 8.35 KY3 2.59 8.56 KY4 2.51 8.97 KY5 2.30 8.88 KY6 2.52 9.57 KY7 2.96 9.62 KY8 3.25 8.89 KY9 2.91 9.46 KY10 2.24 2.56 KY11 1.12 2.88 UCC 1.33 3.00 Deze section, Yunnan Province Sample TS (%) TOC (%) DZ0 0.20 0.33 DZ1 0.28 0.41 DZ2 0.69 0.76 DZ3 0.15 1.05 DZ4 0.70 0.22 DZ5 0.06 0.18 DZ6 0.02 0.25 DZ7 0.65 0.60 UCC

Na (%)

K (%)

P (%)

TC (%) 7.22 7.99 5.04 4.88 8.15 8.00 3.12 4.58

Na (%)

K (%)

P (%)

0.06 0.08 0.07 0.07 0.04 0.09 0.06 0.11 0.10 0.11 0.10 2.89

2.89 4.15 4.03 4.18 4.01 4.17 4.02 3.80 3.94 1.10 1.27 2.80

Pyrite S (%) 0.13 0.21 0.45 0.08 0.62 0.01 0.00 0.46

δ S pyrite 21.62 12.55 13.84

377

34

9.46

TC (%) 0.18 0.14 0.18 0.16 0.17 0.13 0.13 0.17 0.11 8.94 10.82 0.07

Li (ppm) 6.12 6.66 13.41 16.51 7.75 6.86 15.98 13.01 20.00

5.44 2.24 3.57 2.62 2.34 1.80 2.88 3.19 2.80 2.96 1.81

Be (ppm) 0.33 0.35 1.02 1.27 0.61 0.39 1.01 0.79 3.00

Meishucun section, Yunnan Province Sample TS (%) TOC (%) KY1 2.36 KY2 1.89 KY3 1.14 KY4 1.59 KY5 1.04 KY6 1.83 KY7 1.14 KY8 0.95 KY9 1.27 KY10 3.40 KY11 1.32 UCC

0.75 1.06 2.09 1.49 1.60 0.93 1.62 2.04 1.56 0.90 1.17

Deze section, Yunnan Province Sample Sc (ppm) Ti (ppm) DZ0 3.31 343.77 DZ1 3.20 445.05 DZ2 6.22 834.00 DZ3 7.86 1011.94 DZ4 3.65 532.99 DZ5 3.50 526.24 DZ6 6.20 1024.93 DZ7 5.27 795.47 UCC 13.60 4100.00

Pyrite S (%) 1.95 1.55 0.82 1.32 0.97 1.52 0.90 0.70 0.90 1.48 0.79

V (ppm) 25.55 25.76 50.04 61.61 31.44 31.46 52.78 43.53 107.00

378

34

δ S pyrite -3.95 2.23 -3.07 -1.92 0.32 0.18 -14.39 -4.78 -9.06

Li (ppm) 9.19

Be (ppm) 1.27

49.94

2.24

35.95

2.03

20.00

3.00

Mn (ppm) 549.33 308.93 308.48 168.62 192.10 462.53 138.59 230.05 600.00

Co (ppm) 8.49 9.55 8.38 8.67 4.84 7.25 7.99 8.22 17.00

-9.17

Cr (ppm) 15.66 17.90 33.60 43.29 14.05 20.62 36.94 31.63 83.00

Meishucun section, Yunnan Province Sample Sc (ppm) Ti (ppm) KY1 9.30 1442.31 KY2 14.10 3685.30 KY3 14.80 3743.59 KY4 15.70 4197.54 KY5 16.50 4246.14 KY6 16.60 4337.59 KY7 16.00 4221.66 KY8 15.00 4105.55 KY9 16.60 4279.61 KY10 7.30 6434.63 KY11 4.90 8155.67 UCC 13.60 4100.00 Deze section, Yunnan Province Sample Ni (ppm) Cu (ppm) DZ0 10.93 4.66 DZ1 9.31 4.93 DZ2 12.47 7.02 DZ3 11.77 10.04 DZ4 11.33 5.51 DZ5 9.29 4.22 DZ6 5.34 4.91 DZ7 10.57 5.21 UCC 44.00 25.00

V (ppm) 241.10 281.40 459.10 239.70 348.00 153.50 418.60 451.10 358.80 77.70 94.30 107.00

Cr (ppm) 65.70 179.00 299.50 238.70 177.20 101.70 153.80 131.40 133.10 57.40 70.60 83.00

Mn (ppm) 811.90 335.65 376.39 391.41 329.73 344.16 393.59 391.96 388.55 466.17 181.32 600.00

Co (ppm) 8.50

Zn (ppm) 147.46 105.06 51.59 85.58 55.64 121.50 46.38 55.31 71.00

Ga (ppm) 3.31 3.28 8.26 10.29 4.32 3.77 9.48 7.74 17.00

Rb (ppm) 16.64 17.96 45.97 59.71 25.92 21.26 55.85 48.14 112.00

Sr (ppm) 865.94 769.39 670.57 513.43 654.78 832.02 265.36 392.78 350.00

379

20.59

26.11 17.00

Meishucun section, Yunnan Province Sample Ni (ppm) Cu (ppm) KY1 31.60 9.90 KY2 65.80 20.70 KY3 61.20 26.30 KY4 51.10 22.70 KY5 62.00 23.40 KY6 45.70 20.40 KY7 64.00 26.30 KY8 73.60 24.80 KY9 61.90 30.10 KY10 32.00 19.30 KY11 30.60 12.40 UCC 44.00 25.00

Zn (ppm) 148.10 31.80 62.30 45.10 70.20 56.90 69.20 52.40 62.80 16.80 33.20 71.00

Ga (ppm) 10.20 16.00 17.20 18.30 19.80 19.30 19.60 18.40 19.80 5.60 6.50 17.00

Rb (ppm) 53.10 112.30 118.40 120.00 126.10 124.70 129.20 123.10 120.80 33.50 37.50 112.00

Sr (ppm) 68.40 67.40 66.50 66.40 68.30 62.40 68.70 84.00 63.00 528.90 639.00 350.00

Deze section, Yunnan Province Sample Y (ppm) Zr (ppm) DZ0 23.62 10.45 DZ1 16.70 13.05 DZ2 52.13 24.06 DZ3 52.88 30.33 DZ4 13.84 13.44 DZ5 18.12 15.20 DZ6 21.19 35.58 DZ7 35.33 20.44 UCC 22.00 190.00

Nb (ppm) 1.14 1.29 2.70 2.78 1.62 1.53 3.19 2.24 12.00

Mo (ppm) 1.47 0.39 0.54 1.32 1.08 1.23 0.28 0.70 1.50

Cd (ppm) 0.21 0.40 0.16 0.12 0.10 0.16 0.14 0.03 0.0098

Sn (ppm) 0.86 0.91 2.15 1.68 0.90 1.01 1.55 1.14 5.50

380

Meishucun section, Yunnan Province Sample Y (ppm) Zr (ppm) KY1 46.00 105.40 KY2 32.00 179.80 KY3 40.10 190.60 KY4 34.30 212.90 KY5 33.90 224.60 KY6 29.00 206.10 KY7 33.00 199.50 KY8 41.70 240.70 KY9 30.50 222.10 KY10 253.50 166.20 KY11 259.60 218.20 UCC 22.00 190.00

Nb (ppm) 15.40 12.70 13.70 14.30 14.90 14.90 14.70 15.20 14.40 28.80 36.00 12.00

Mo (ppm) 3.75 6.07 8.07 4.95 6.59 3.70 9.44 8.37 5.11 2.80 1.99 1.50

Cd (ppm) 0.18

Sn (ppm) 2.03

0.10

2.43

0.23

0.13

0.0098

5.50

Deze section, Yunnan Province Sample Cs (ppm) Ba (ppm) DZ0 1.14 1823.04 DZ1 1.34 799.53 DZ2 3.04 777.90 DZ3 5.00 865.54 DZ4 2.43 701.71 DZ5 1.86 2163.15 DZ6 4.25 853.00 DZ7 3.73 1627.31 UCC 4.60 550.00

La (ppm) 19.01 14.53 43.75 45.88 13.19 18.03 25.14 33.65 30.00

Ce (ppm) 17.50 13.57 47.20 52.35 14.97 18.79 30.07 40.08 64.00

Pr (ppm) 3.58 2.72 8.81 9.60 2.57 3.32 4.99 6.51 7.10

Nd (ppm) 14.93 11.16 35.97 40.04 10.34 13.27 19.33 27.32 26.00

381

Meishucun section, Yunnan Province Sample Cs (ppm) Ba (ppm) KY1 3.93 270.80 KY2 519.60 KY3 502.70 KY4 514.90 KY5 8.33 552.30 KY6 532.20 KY7 546.00 KY8 566.00 KY9 765.70 KY10 2.09 238.70 KY11 263.10 UCC 4.60 550.00

La (ppm) 25.90 32.40 33.10 37.90 41.00 36.90 35.30 35.80 29.00 53.50 67.00 30.00

Ce (ppm) 47.30 54.00 60.50 71.10 73.50 67.10 66.60 69.90 57.90 169.00 203.50 64.00

Pr (ppm) 4.51

7.10

Nd (ppm) 24.50 26.50 29.10 32.60 34.60 31.20 32.00 34.90 25.90 141.90 156.80 26.00

Deze section, Yunnan Province Sample Sm (ppm) Eu (ppm) DZ0 2.98 0.93 DZ1 2.26 0.55 DZ2 6.96 1.48 DZ3 7.62 1.66 DZ4 2.12 0.47 DZ5 2.60 0.80 DZ6 3.58 0.79 DZ7 4.77 1.22 UCC 4.50 0.88

Gd (ppm) 3.11 2.35 7.36 8.21 2.08 2.63 3.54 5.26 3.80

Tb (ppm) 0.42 0.31 0.95 1.02 0.27 0.34 0.46 0.63 0.64

Dy (ppm) 2.89 2.18 6.32 6.85 1.90 2.42 3.05 4.48 3.50

Ho (ppm) 0.61 0.45 1.33 1.43 0.39 0.47 0.71 0.87 0.80

Gd (ppm) 3.96

Tb (ppm) 0.61

Dy (ppm) 4.50

Ho (ppm) 0.93

5.43

0.64

4.21

0.80

76.11

9.60

51.00

8.63

3.80

0.64

3.50

0.80

Meishucun section, Yunnan Province Sample Sm (ppm) Eu (ppm) KY1 3.78 0.48 KY2 KY3 KY4 KY5 5.54 1.14 KY6 KY7 KY8 KY9 KY10 60.79 18.87 KY11 UCC 4.50 0.88

382

8.48

28.00

Deze section, Yunnan Province Sample Er (ppm) Tm (ppm) DZ0 1.79 0.22 DZ1 1.38 0.18 DZ2 3.79 0.47 DZ3 3.83 0.47 DZ4 1.17 0.16 DZ5 1.36 0.19 DZ6 2.03 0.26 DZ7 2.52 0.31 UCC 2.30 0.33 Meishucun section, Yunnan Province Sample Er (ppm) Tm (ppm) KY1 2.99 0.41 KY2 KY3 KY4 KY5 2.51 0.34 KY6 KY7 KY8 KY9 KY10 19.37 1.94 KY11 UCC 2.30 0.33

Yb (ppm) 1.27 1.08 2.42 2.31 0.95 1.07 1.50 1.65 2.20

Lu (ppm) 0.19 0.17 0.36 0.33 0.14 0.16 0.22 0.24 0.32

Hf (ppm) 0.24 0.31 0.64 0.84 0.39 0.35 0.94 0.51 5.80

Ta (ppm) 0.15 0.11 0.12 0.26 0.73 0.17 0.25 0.16 1.00

Yb (ppm) 2.44

Lu (ppm) 0.39

Hf (ppm) 2.01

Ta (ppm) 0.46

2.04

0.32

1.95

0.49

8.72

1.12

0.25

0.05

2.20

0.32

5.80

1.00

383

Deze section, Yunnan Province Sample W (ppm) Pb (ppm) DZ0 44.13 10.27 DZ1 42.66 10.11 DZ2 34.01 20.55 DZ3 60.86 20.86 DZ4 16.28 12.42 DZ5 32.11 10.90 DZ6 41.63 6.72 DZ7 41.17 9.66 UCC 2.00 17.00 Meishucun section, Yunnan Province Sample W (ppm) Pb (ppm) KY1 44.84 37.50 KY2 28.20 KY3 20.50 KY4 29.80 KY5 65.71 22.60 KY6 13.30 KY7 9.60 KY8 9.50 KY9 9.80 KY10 108.64 13.20 KY11 14.90 UCC 2.00 17.00

Bi (ppm) 0.04 0.05 0.09 0.11 0.06 0.05 0.07 0.06 0.00127

Th (ppm) 1.67 2.02 4.64 6.12 2.70 2.14 5.07 4.62 10.70

U (ppm)

Bi (ppm) 0.11

Th (ppm) 6.60 9.40 10.20 11.10 11.50 11.50 10.40 11.40 10.90 15.10 20.10 10.70

U (ppm) 10.10

0.16

0.23 0.00127

384

Mo/Sc 2.45 1.63 2.97 4.00 0.89 2.35 2.90 2.18 2.80

10.26

45.70 2.80

0.44 0.12 0.09 0.17 0.30 0.35 0.05 0.13 0.11

Mo/Sc 0.40 0.43 0.55 0.31 0.40 0.22 0.59 0.56 0.31 0.38 0.41 0.11

Deze section, Yunnan Province Sample V/Sc U/Sc DZ0 7.72 0.74 DZ1 8.05 0.51 DZ2 8.05 0.48 DZ3 7.84 0.51 DZ4 8.62 0.24 DZ5 9.00 0.67 DZ6 8.51 0.47 DZ7 8.25 0.41 UCC 7.87 0.21 Meishucun section, Yunnan Province Sample V/Sc U/Sc KY1 25.92 KY2 19.96 KY3 31.02 KY4 15.27 KY5 21.09 KY6 9.25 KY7 26.16 KY8 30.07 KY9 21.61 KY10 10.64 KY11 19.24 UCC 7.87

Mo/TOC (10-4)

4.53 0.93 0.71 1.25 4.86 6.96 1.12 1.17

Mo/TOC (10-4)

1.09

0.62

6.26

5.01 5.71 3.87 3.33 4.12 3.97 5.84 4.11 3.28 3.12 1.71

0.21

V/TOC (10-4)

Th/U

78.59 62.17 65.58 58.45 140.92 177.33 209.86 72.61

V/TOC (10-4)

321.81 264.72 220.19 161.20 217.64 164.86 258.71 221.67 230.59 86.65 80.94

V/(V+Ni)

0.68 1.23 1.56 1.53 3.04 0.91 1.75 2.12 3.82

Th/U

V/(V+Ni)

0.65

1.12

0.33 3.82

385

0.70 0.73 0.80 0.84 0.74 0.77 0.91 0.80 0.71

0.88 0.81 0.88 0.82 0.85 0.77 0.87 0.86 0.85 0.71 0.76 0.71

Iron speciation analysis Changxingpo Mine, Guizhou Province Fe py Fe carb Fe ox Sample (wt%) (wt%) (wt%) CXP1 0.53 0.28 0.02 CXP2 0.66 0.29 0.02 CXP3 0.82 0.48 0.02 CXP4 0.48 0.49 0.04 CXP8 0.60 0.57 0.04 CXP9 0.67 0.55 0.04 CXP10 1.03 0.51 0.03 CXP11 0.36 0.40 0.03 CXP12 0.30 0.41 0.03 CXP13 0.16 0.52 0.03 CXP14 0.16 0.53 0.03 CXP15 0.21 0.59 0.03 CXP16 0.35 0.72 0.04 CXP17 0.17 0.59 0.03

Position: 27°34'10.49"N, 109°23'7.95"E Fe mag FeHR FeT (wt%) (wt%) (wt%) FeHR/FeT 0.13 0.97 1.35 0.72 0.10 1.07 1.51 0.71 0.06 1.38 4.34 0.32 0.26 1.28 4.03 0.32 0.21 1.42 4.14 0.34 0.09 1.34 2.39 0.56 0.08 1.65 2.95 0.56 0.06 0.85 1.83 0.46 0.06 0.80 1.88 0.43 0.09 0.80 1.53 0.52 0.08 0.80 1.24 0.66 0.09 0.93 1.53 0.61 0.15 1.26 1.79 0.70 0.12 0.91 1.80 0.51

Fepy/FeHR 0.55 0.62 0.59 0.37 0.42 0.50 0.62 0.42 0.38 0.20 0.19 0.22 0.28 0.18

Maoshi section, Guizhou Province Fe py Fe carb Fe ox Sample (wt%) (wt%) (wt%) MS108 0.00 0.00 0.01 MS107 0.00 0.00 0.05 MS102 0.14 0.23 0.12 MS100 0.01 0.23 0.73 MS1 0.10 0.24 0.32 MS2 1.50 0.31 0.24 MS3 0.01 0.06 0.23 MS4 0.64 0.26 0.79 MS5 0.01 0.06 0.42 MS6 0.01 0.10 0.65 MS7 1.90 0.28 0.29 MS8 1.48 0.23 0.34 MS9 2.20 0.42 0.23 MS10 0.83 0.30 0.97 MS11 1.43 0.43 1.33 MS12 0.12 0.05 0.08

Position: 27°48'7.64"N / 106°43'58.10"E Fe mag FeHR FeT (wt%) (wt%) (wt%) FeHR/FeT 0.00 0.01 0.04 0.17 0.00 0.05 0.10 0.48 0.00 0.49 0.47 1.04 0.01 0.99 1.32 0.75 0.01 0.68 1.02 0.66 0.01 2.07 2.18 0.95 0.01 0.31 0.62 0.50 0.01 1.70 2.07 0.82 0.01 0.50 0.65 0.76 0.02 0.78 1.07 0.73 0.01 2.48 2.57 0.97 0.01 2.07 2.21 0.93 0.01 2.87 2.82 1.01 0.03 2.13 3.10 0.69 0.02 3.20 3.30 0.97 0.01 0.26 0.46 0.56

Fepy/FeHR 0.12 0.04 0.28 0.01 0.15 0.73 0.04 0.38 0.02 0.01 0.77 0.72 0.77 0.39 0.45 0.47

386

Jiulongwan section, Hubei Province Fe py Fe carb Fe ox Sample (wt%) (wt%) (wt%) JLW1 0.92 0.39 0.07 JLW2 0.45 0.29 0.00 JLW3 1.40 0.64 0.06 JLW4 1.20 0.67 0.04 JLW5 0.72 0.58 0.03 JLW6 0.33 0.32 0.04 JLW7 0.60 0.47 0.06 JLW8 0.99 0.53 0.06 JLW9 0.21 0.22 0.12 JLW10 0.52 0.45 0.11 JLW11 0.24 0.19 0.03 JLW12 1.39 0.70 0.07 JLW13 0.11 0.23 0.11 JLW14 0.02 0.42 0.33 JLW15 0.91 0.53 0.06 JLW16 0.38 0.44 0.03 JLW17 1.30 0.63 0.11 JLW18 0.54 0.39 0.04 JLW19 1.10 0.52 0.04 JLW20 0.02 0.12 0.06 JLW21 0.04 0.54 0.53 JLW22 0.04 0.59 0.32 JLW23 0.07 0.43 0.34 JLW24 0.58 0.64 0.08 JLW25 0.44 0.53 0.10 JLW26 0.26 0.33 0.04 JLW27 1.64 0.43 0.04 JLW28 0.07 0.59 0.39 JLW29 0.62 0.48 0.08 JLW30 0.52 0.52 0.16 JLW31 0.75 0.42 0.04

Position: 30°48'23.91"N, 111° 3'14.76"E Fe mag FeHR FeT (wt%) (wt%) (wt%) FeHR/FeT 0.02 1.39 1.76 0.79 0.00 0.75 0.84 0.89 0.03 2.12 2.23 0.95 0.05 1.97 2.13 0.92 0.02 1.35 1.38 0.98 0.02 0.70 0.80 0.88 0.04 1.18 1.97 0.60 0.05 1.62 2.15 0.75 0.00 0.56 0.52 1.08 0.02 1.11 1.24 0.89 0.00 0.47 1.83 0.25 0.09 2.25 2.47 0.91 0.01 0.46 0.59 0.77 0.03 0.79 0.88 0.90 0.07 1.57 1.65 0.95 0.03 0.87 0.92 0.94 0.12 2.16 2.53 0.85 0.03 0.99 1.11 0.89 0.04 1.70 0.56 3.03 0.00 0.20 0.96 0.21 0.05 1.16 1.41 0.82 0.05 1.00 1.31 0.77 0.01 0.86 0.76 1.13 0.10 1.41 1.45 0.97 0.05 1.12 1.23 0.91 0.02 0.64 0.68 0.95 0.05 2.16 2.20 0.98 0.08 1.13 1.34 0.84 0.16 1.33 1.51 0.88 0.16 1.36 1.37 0.99 0.07 1.27 1.45 0.88

387

Fepy/FeHR 0.66 0.61 0.66 0.61 0.53 0.47 0.51 0.61 0.38 0.47 0.52 0.62 0.24 0.02 0.58 0.43 0.60 0.54 0.65 0.07 0.03 0.04 0.08 0.41 0.40 0.40 0.76 0.06 0.47 0.38 0.59

Jiulongwan section, Hubei Province Fe py Fe carb Fe ox Sample (wt%) (wt%) (wt%) JLW40 4.02 0.60 0.03 JLW41 0.44 0.31 0.00 JLW42 0.16 0.12 0.00 JLW43 1.78 0.56 0.01 JLW44 1.92 0.54 0.04 JLW45 2.27 0.63 0.06 JLW46 1.85 0.53 0.01 JLW47 1.88 0.59 0.02 JLW48 1.86 0.60 0.05 JLW49 2.07 0.53 0.03 JLW50 2.11 0.52 0.01 JLW51 2.22 0.53 0.03 JLW52 2.24 0.56 0.05 JLW53 3.19 0.61 0.02 JLW54 3.05 0.80 0.09 JLW55 2.29 0.54 0.03 JLW56 2.39 0.69 0.16 JLW58 2.38 0.62 0.03 JLW59 1.43 0.65 0.09 JLW60 1.14 0.47 0.01 JLW61 0.33 0.20 0.01 JLW62 0.24 0.28 0.02 JLW63 0.17 0.09 0.00 JLW64 0.20 0.07 0.00 JLW65 0.21 0.08 0.00

Position: 30°48'23.91"N, 111° 3'14.76"E Fe mag FeHR FeT (wt%) (wt%) (wt%) FeHR/FeT 0.01 4.65 4.82 0.97 0.00 0.76 0.76 1.00 0.00 0.28 0.28 1.01 0.00 2.36 2.34 1.01 0.03 2.53 2.34 1.08 0.02 2.99 2.75 1.09 0.01 2.40 2.41 0.99 0.01 2.51 2.38 1.05 0.01 2.53 2.49 1.01 0.01 2.64 2.45 1.08 0.01 2.65 2.50 1.06 0.01 2.79 2.71 1.03 0.01 2.86 3.04 0.94 0.01 3.83 3.58 1.07 0.01 3.95 3.86 1.02 0.00 2.87 2.97 0.97 0.03 3.26 3.25 1.00 0.01 3.04 2.94 1.04 0.00 2.18 2.46 0.88 0.02 1.65 2.31 0.71 0.00 0.54 0.55 0.99 0.00 0.55 0.55 1.00 0.00 0.26 0.27 1.00 0.00 0.28 0.35 0.79 0.00 0.29 0.30 0.98

Fepy/FeHR 0.86 0.58 0.57 0.76 0.76 0.76 0.77 0.75 0.74 0.78 0.80 0.80 0.78 0.83 0.77 0.80 0.73 0.78 0.66 0.69 0.61 0.44 0.64 0.74 0.72

Jijiawan section, Hubei Province Fe py Fe carb Sample (wt%) (wt%) JJ1 0.71 0.67 JJ2 0.39 0.58 JJ3 0.60 0.59 JJ4 0.79 0.50 JJ5 0.36 0.19 JJ6 1.00 0.36 JJ7 0.64 0.25 JJ8 0.07 0.06 JJ9 0.69 0.32 JJ10 0.64 0.28 JJ11 0.77 0.23 JJ12 1.30 0.49

Position: 30°53'0.93"N, 110°52'47.25"E Fe mag FeHR FeT (wt%) (wt%) (wt%) FeHR/FeT 0.11 2.10 3.24 0.65 0.06 1.17 1.55 0.75 0.05 1.44 1.86 0.78 0.03 1.36 1.57 0.87 0.01 0.65 0.96 0.67 0.01 1.51 1.53 0.99 0.01 1.13 1.29 0.87 0.00 0.15 0.18 0.86 0.01 1.07 1.07 1.00 0.01 1.02 1.01 1.00 0.01 1.13 1.21 0.93 0.01 1.95 1.96 0.99

Fepy/FeHR 0.34 0.33 0.41 0.59 0.56 0.66 0.57 0.49 0.64 0.63 0.69 0.66

Fe ox (wt%) 0.62 0.14 0.21 0.03 0.08 0.14 0.23 0.01 0.05 0.09 0.11 0.16

388

Wuhe section, Hubei Province Fe py Fe carb Sample (wt%) (wt%) WH1 0.16 0.12 WH5 0.02 0.01 WH7 0.02 0.01 WH9 0.00 0.01 WH11 0.01 0.01 WH14 0.01 0.00 WH17 0.01 0.00 WH19 0.02 0.01

Fe ox (wt%) 0.08 0.00 0.00 0.00 0.00 0.01 0.01 0.01

Position: 30°46'51.96"N, 111° 2'15.41"E Fe mag FeHR FeT (wt%) (wt%) (wt%) FeHR/FeT 0.00 0.36 0.35 1.03 0.00 0.03 0.10 0.30 0.00 0.03 0.04 0.79 0.00 0.01 0.00 0.02 0.08 0.24 0.00 0.02 0.06 0.34 0.00 0.02 0.03 0.76 0.00 0.04 0.06 0.71

Fepy/FeHR 0.44 0.63 0.58 0.36 0.60 0.45 0.41 0.57

Huanglian section, Guizhou Province Fe py Fe carb Fe ox Sample (wt%) (wt%) (wt%) HL1 0.24 0.33 0.05 HL2 0.09 0.06 0.09 HL5 0.01 0.02 0.32 HL6 0.06 0.02 0.04 HL7 0.01 0.03 0.14 HL8 0.28 0.07 0.13 HL9 0.15 0.09 0.26 HL13 0.02 0.03 0.08 HL12 0.00 0.01 0.03 HL14 0.02 0.02 0.01 HL15 0.01 0.04 0.01 HL10 0.00 0.01 0.04 HL11 0.16 0.09 0.22

Position: 28°11'51.19"N, 109°15'43.14"E Fe mag FeHR FeT (wt%) (wt%) (wt%) FeHR/FeT 0.00 0.63 0.69 0.92 0.00 0.23 0.57 0.41 0.00 0.35 0.48 0.72 0.00 0.12 0.12 1.01 0.00 0.19 0.23 0.85 0.02 0.50 0.54 0.92 0.00 0.50 0.57 0.87 0.00 0.12 0.13 0.96 0.00 0.04 0.06 0.72 0.00 0.04 0.10 0.45 0.01 0.07 0.09 0.81 0.00 0.05 0.27 0.18 0.00 0.47 0.57 0.83

Fepy/FeHR 0.39 0.37 0.03 0.47 0.06 0.56 0.31 0.13 0.05 0.40 0.20 0.01 0.34

389

Longbizui section, Guizhou Province Fe py Fe carb Fe ox Sample (wt%) (wt%) (wt%) LBZ-2 0.33 0.10 0.03 LBZ-3 0.14 0.04 0.08 LBZ-4 0.21 0.05 0.03 LBZ-5 0.21 0.06 0.18 LBZ-6 0.83 0.09 0.06 LBZ-7 0.75 0.06 0.11 LBZ-8 0.40 0.11 0.23 LBZ-9 0.58 0.27 0.04 LBZ-10 0.34 0.09 0.04 LBZ-11 0.35 0.24 0.08 LBZ-12 1.54 0.42 0.13 LBZ-13 0.03 0.04 0.54 LBZ-14 0.30 0.09 0.11 LBZ-15 0.36 0.08 0.32 LBZ-16 0.06 0.03 0.08 LBZ-17 0.26 0.10 0.19 LBZ-18 0.05 0.03 0.01 LBZ-19 0.18 0.08 0.03 LBZ-20 0.24 0.13 0.02 LBZ-21 1.16 0.27 0.01 LBZ-22 2.61 0.53 0.12 LBZ-23 1.09 0.33 0.07 LBZ-24 1.30 0.39 0.27 LBZ-25 2.89 0.67 0.10 LBZ-26 1.78 0.49 0.33

Position: 28°11'51.19"N, 109°15'43.14"E Fe mag FeHR FeT (wt%) (wt%) (wt%) FeHR/FeT 0.00 0.46 0.44 1.05 0.00 0.26 0.33 0.81 0.00 0.30 0.34 0.86 0.00 0.46 0.56 0.81 0.00 0.99 1.09 0.91 0.00 0.92 1.22 0.76 0.01 0.74 0.83 0.89 0.00 0.90 0.90 1.00 0.00 0.47 0.47 1.00 0.00 0.67 1.51 0.45 0.00 2.10 1.95 1.08 0.02 0.62 0.71 0.88 0.00 0.50 0.77 0.65 0.01 0.76 0.97 0.79 0.00 0.18 0.18 0.99 0.00 0.54 0.54 1.01 0.00 0.09 0.10 0.88 0.00 0.29 0.37 0.78 0.00 0.39 0.53 0.74 0.00 1.44 1.74 0.83 0.01 3.27 3.16 1.03 0.00 1.49 2.36 0.63 0.00 1.96 1.85 1.06 0.01 3.66 3.59 1.02 0.00 2.60 2.62 0.99

390

Fepy/FeHR 0.71 0.55 0.72 0.47 0.84 0.81 0.53 0.65 0.73 0.52 0.73 0.04 0.60 0.47 0.35 0.47 0.60 0.62 0.62 0.81 0.80 0.73 0.66 0.79 0.69

Jijiawan section, Hubei Province Fe py Fe carb Sample (wt%) (wt%) JJL2 0.22 0.07 JJL1 0.27 0.08 JJL1a 1.41 0.52 JJL1b 0.82 0.54 JJL3 2.00 1.25 JJL5 2.19 0.61 JJL6 1.94 0.67 JJL7 2.62 0.81 JJL8 1.71 0.70 JJL9 1.72 0.69 JJL10 1.33 0.63

Fe ox (wt%) 0.02 0.00 0.17 0.11 0.11 0.14 0.02 0.04 0.09 0.01 0.25

Position: 30°53'0.93"N, 110°52'47.25"E Fe mag FeHR FeT (wt%) (wt%) (wt%) FeHR/FeT 0.00 0.31 0.32 0.96 0.00 0.35 0.37 0.95 0.00 2.11 2.28 0.92 0.00 1.48 1.61 0.92 0.03 3.39 3.51 0.97 0.01 2.95 2.95 1.00 0.01 2.63 2.51 1.05 0.00 3.47 3.49 0.99 0.00 2.50 2.51 1.00 0.01 2.43 2.45 0.99 0.00 2.21 2.25 0.98

Fepy/FeHR 0.71 0.76 0.67 0.56 0.59 0.74 0.74 0.75 0.68 0.71 0.60

Wuhe section, Hubei Province Fe py Fe carb Sample (wt%) (wt%) YS107 0.07 0.07 YS108 0.06 0.18 YS113 0.18 0.10 YS114 0.16 0.07 YS115 0.31 0.13 YS0c 0.15 0.04 YS1 0.32 0.23 YS2 1.18 1.11 YS3 0.57 1.08

Fe ox (wt%) 0.19 0.45 0.09 0.16 0.00 0.08 0.03 0.03 0.05

Position: 30°46'51.96"N, 111° 2'15.41"E Fe mag FeHR FeT (wt%) (wt%) (wt%) FeHR/FeT 0.00 0.32 0.38 0.85 0.02 0.70 0.83 0.85 0.00 0.37 0.54 0.69 0.02 0.41 0.52 0.80 0.00 0.43 0.53 0.81 0.01 0.27 0.36 0.75 0.01 0.59 0.60 0.99 0.02 2.35 3.52 0.67 0.02 1.72 2.59 0.66

Fepy/FeHR 0.21 0.09 0.49 0.38 0.71 0.54 0.53 0.50 0.33

Zhongnan section, Guizhou Province Fe py Fe carb Fe ox Sample (wt%) (wt%) (wt%) ZN0A 0.01 0.05 0.58 ZN0B 0.02 0.07 0.90 ZN0C 0.06 0.10 1.52 ZN1 0.02 0.06 0.26 ZN2 0.01 0.14 1.56 ZN3 0.86 0.14 0.59 ZN4 1.96 1.79 0.88 ZN5 8.15 0.47 0.80 ZN6 15.75 0.44 0.33 ZN7 0.02 0.27 0.46 ZN8 0.03 0.42 1.02 ZN9 0.01 0.05 0.21 ZN10 0.03 0.23 0.30 ZN11 0.02 0.27 0.46 ZN12 0.01 0.11 0.47 ZN13 0.01 0.08 0.24 ZN14 0.01 0.06 0.07

Position: 27°41'24.67"N / 106°40'47.38"E Fe mag FeHR FeT (wt%) (wt%) (wt%) FeHR/FeT 0.03 0.67 0.72 0.93 0.02 1.00 1.09 0.92 0.03 1.71 1.80 0.95 0.01 0.35 0.38 0.92 0.04 1.75 1.92 0.91 0.04 1.62 1.74 0.93 0.14 4.77 13.01 0.37 0.02 9.45 9.87 0.96 0.02 16.54 15.35 1.08 0.03 0.78 1.08 0.72 0.03 1.50 1.67 0.90 0.01 0.29 0.43 0.67 0.00 0.56 0.58 0.96 0.03 0.78 1.03 0.76 0.01 0.61 0.89 0.68 0.00 0.32 0.59 0.55 0.00 0.15 0.45 0.33

Fepy/FeHR 0.02 0.02 0.03 0.06 0.01 0.53 0.41 0.86 0.95 0.03 0.02 0.05 0.06 0.02 0.02 0.02 0.07

391

Xiaotan section, Sichuan Province Fe py Fe carb Fe ox Sample (wt%) (wt%) (wt%) XT1 0.01 0.16 1.20 XT2 0.01 0.12 2.43 XT3 0.00 0.21 0.37 XT4 0.00 0.13 0.74 XT5 0.00 0.28 0.89 XT6 0.04 0.15 0.77 XT7 0.00 0.23 0.84 XT8 0.01 0.33 0.60 XT9 0.01 0.26 0.77 XT10 0.01 0.34 0.76 XT11 0.01 0.24 1.01 XT12 0.01 0.15 0.34 XT13 0.01 0.14 0.47 XT14 0.01 0.17 0.46 XT15 0.01 0.20 0.68 XT16 0.01 0.14 0.41 XT17 0.00 0.19 0.81 XT18 0.01 0.19 0.36 XT19 0.01 0.16 0.55 XT20 0.01 0.19 0.53 XT21 0.01 0.20 0.51 XT22 0.01 0.23 0.89 XT23 0.01 0.19 0.41 XT24 0.01 0.28 0.71 XT25 0.01 0.24 0.60 XT26 0.01 0.32 0.47 XT27 0.01 0.18 0.29 XT28 0.01 0.33 0.85 XT29 0.00 0.30 0.60

Position: 28° 7'28.68"N, 103°27'58.96"E Fe mag FeHR FeT (wt%) (wt%) (wt%) FeHR/FeT 0.10 1.46 1.58 0.92 0.10 2.65 3.28 0.81 0.03 0.61 0.94 0.65 0.09 0.96 1.63 0.59 0.06 1.23 1.64 0.75 0.07 1.04 1.70 0.61 0.12 1.18 1.64 0.72 0.11 1.05 1.51 0.69 0.07 1.11 1.56 0.71 0.03 1.14 1.50 0.76 0.04 1.29 1.64 0.79 0.08 0.58 1.19 0.48 0.04 0.66 1.07 0.62 0.07 0.70 1.22 0.57 0.14 1.03 1.68 0.61 0.15 0.70 1.54 0.45 0.18 1.19 2.31 0.51 0.13 0.69 1.46 0.47 0.14 0.86 1.54 0.56 0.11 0.84 1.72 0.49 0.21 0.93 1.77 0.53 0.12 1.25 1.99 0.63 0.19 0.81 1.69 0.48 0.20 1.20 2.29 0.52 0.15 0.99 1.94 0.51 0.12 0.92 1.63 0.56 0.16 0.64 1.41 0.46 0.25 1.44 3.50 0.41 0.41 1.32 2.54 0.52

392

Fepy/FeHR 0.01 0.00 0.00 0.00 0.00 0.04 0.00 0.01 0.01 0.01 0.01 0.01 0.02 0.01 0.01 0.01 0.00 0.01 0.01 0.01 0.01 0.01 0.02 0.01 0.01 0.01 0.01 0.01 0.00

Xiaotan section, Sichuan Province Fe py Fe carb Fe ox Sample (wt%) (wt%) (wt%) XTY1 0.01 0.33 0.28 XTY2 0.00 0.54 0.35 XTY3 0.00 0.60 0.34 XTY4 0.01 0.52 0.29 XTY5 0.01 0.48 0.16 XTY6 0.01 0.55 0.32 XTY7 0.01 0.44 0.31 XTY8 0.01 0.44 0.16 XTY9 0.02 0.48 0.22 XTY10 0.01 0.39 0.17 XTY11 0.01 0.45 0.26 XTY12 0.01 0.43 0.52 XTY13 0.01 0.50 0.53 XTY14 0.11 0.65 0.30 XTY15 0.17 0.41 0.22 XTY16 0.00 0.31 0.22 XTY17 0.00 0.43 0.77 XTY17a 0.01 0.50 0.49 XTY17b 0.00 0.52 0.25 XTY17c 0.01 0.44 0.25 XTY17d 0.02 0.58 0.47 XTY17e 0.03 0.55 0.43 XTY17f 0.02 0.44 0.35 XTY18 0.10 0.49 0.28 XTY18a 0.00 0.56 0.96 XTY18b 0.02 0.44 0.43 XTY18c 0.01 0.37 0.51 XTY18d 0.00 0.49 0.45 XTY18e 0.00 0.59 0.40 XTY19 0.01 0.44 0.38 XTY19a 0.07 0.39 0.22 XTY19b 0.00 0.44 0.33 XTY19c 0.07 0.43 0.27 XTY19d 0.01 0.37 0.16 XTY19e 0.02 0.70 0.62 XTY19f 0.01 0.39 0.45 XTY20 0.12 0.64 0.86 XTY21 0.00 0.48 0.40 XTY22 0.01 0.43 0.37 XTY23 0.06 0.82 0.68 XTY24 0.01 0.41 0.33 XTY25 0.01 0.62 0.54 XTY26 0.09 0.48 0.34 XTY27 0.00 1.18 1.24 XTY28 0.06 0.77 0.35 XTY29 0.00 0.57 0.58 XTY30 0.00 0.80 1.16

Position: 28° 7'28.68"N, 103°27'58.96"E Fe mag FeHR FeT (wt%) (wt%) (wt%) FeHR/FeT 0.25 0.87 1.60 0.54 0.37 1.26 2.65 0.48 0.33 1.27 3.09 0.41 0.31 1.13 2.64 0.43 0.30 0.94 2.01 0.47 0.29 1.16 2.25 0.52 0.18 0.93 2.30 0.41 0.29 0.90 1.70 0.53 0.18 0.90 1.67 0.54 0.25 0.82 1.48 0.55 0.23 0.96 1.56 0.61 0.36 1.32 2.09 0.63 0.16 1.20 2.45 0.49 0.19 1.24 2.29 0.54 0.14 0.95 2.24 0.42 0.20 0.74 1.33 0.56 0.25 1.45 2.65 0.55 0.27 1.27 2.46 0.52 0.21 0.99 2.16 0.46 0.28 0.98 1.82 0.54 0.24 1.31 2.13 0.62 0.23 1.23 2.34 0.53 0.20 1.01 1.74 0.58 0.21 1.08 2.21 0.49 0.24 1.77 3.14 0.56 0.18 1.07 1.75 0.61 0.16 1.04 1.75 0.59 0.22 1.16 1.61 0.72 0.28 1.27 2.24 0.57 0.21 1.03 1.76 0.59 0.24 0.92 1.63 0.56 0.24 1.01 1.99 0.51 0.23 0.99 1.90 0.52 0.18 0.72 1.41 0.51 0.19 1.52 2.82 0.54 0.15 1.00 1.72 0.58 0.12 1.74 3.04 0.57 0.18 1.07 1.79 0.59 0.20 1.01 1.96 0.51 0.15 1.71 3.26 0.52 0.18 0.93 1.68 0.55 0.24 1.40 2.44 0.58 0.09 0.99 2.76 0.36 0.21 2.62 4.44 0.59 0.22 1.40 2.53 0.55 0.31 1.46 2.95 0.50 0.21 2.16 4.27 0.51

393

Fepy/FeHR 0.01 0.00 0.00 0.00 0.01 0.00 0.01 0.01 0.02 0.01 0.01 0.01 0.01 0.09 0.18 0.01 0.00 0.01 0.00 0.01 0.02 0.02 0.02 0.09 0.00 0.01 0.00 0.00 0.00 0.01 0.08 0.00 0.07 0.01 0.01 0.01 0.07 0.00 0.01 0.04 0.01 0.01 0.09 0.00 0.05 0.00 0.00

Xiaotan section, Sichuan Province Fe py Fe carb Fe ox Sample (wt%) (wt%) (wt%) XTY35 0.06 0.29 0.40 XTY36 0.01 0.58 0.45 XTY37 0.08 0.62 0.70 XTY38 0.01 0.56 0.66 XTY39 0.00 0.61 1.30 XTY40 0.05 0.50 0.47 XTY41 0.15 0.67 0.60 XTY42 0.12 0.55 0.73 XTY43 0.09 0.58 0.73 XTY44 0.03 0.56 0.79 XTY45 0.20 0.60 0.63 XTY46 0.16 0.69 0.06 XTY47 0.08 0.63 0.16 XTY48 0.19 0.63 0.24 XTY49 0.17 0.64 0.25 XTY50 0.17 0.62 0.09 XTY51 0.73 0.57 0.11 XTY52 0.73 0.50 0.10 XTY53 0.80 0.66 0.14 XTY54 0.59 0.56 0.12 XTY55 0.30 0.66 0.12 XTY56 0.34 0.75 0.29 XTY57 0.02 0.76 0.30 XTY58 0.33 0.75 0.21 XTY59 0.01 0.63 0.14 XTY60 0.10 0.66 0.04 XTY61 0.02 0.76 0.17

Position: 28° 7'28.68"N, 103°27'58.96"E Fe mag FeHR FeT (wt%) (wt%) (wt%) FeHR/FeT 0.04 0.78 1.56 0.50 0.22 1.25 3.10 0.40 0.25 1.65 3.37 0.49 0.32 1.56 3.33 0.47 0.18 2.10 5.31 0.40 0.08 1.10 2.38 0.46 0.18 1.60 4.51 0.35 0.16 1.56 4.70 0.33 0.16 1.55 3.83 0.41 0.17 1.54 4.60 0.34 0.15 1.57 4.54 0.34 0.07 0.99 2.83 0.35 0.11 0.97 4.32 0.23 0.14 1.21 3.99 0.30 0.13 1.19 4.21 0.28 0.06 0.94 2.70 0.35 0.14 1.54 4.18 0.37 0.13 1.46 4.23 0.35 0.15 1.74 4.49 0.39 0.15 1.41 4.77 0.30 0.18 1.26 4.24 0.30 0.18 1.56 4.07 0.38 0.21 1.29 4.28 0.30 0.19 1.48 4.42 0.34 0.17 0.95 4.26 0.22 0.12 0.91 4.27 0.21 0.14 1.09 3.29 0.33

Xiaotan (high resolution sampling within the lower Shiyantou) Fe py Fe carb Fe ox Fe mag FeHR Sample (wt%) (wt%) (wt%) (wt%) (wt%) XTS1 0.00 0.34 0.46 0.05 0.86 XTS2 0.01 0.28 0.51 0.05 0.85 XTS3 0.01 0.49 0.35 0.01 0.85 XTS4 0.00 0.22 0.49 0.04 0.76 XTS5 0.00 0.29 0.44 0.07 0.80 XTS6 0.00 0.33 0.83 0.07 1.22 XTS7 0.00 0.39 1.00 0.07 1.46 XTS8 0.00 0.62 1.54 0.34 2.49 XTS9 0.01 0.40 1.06 0.05 1.51 XTS10 0.00 0.48 1.61 0.06 2.16 XTS11 0.01 0.34 0.93 0.02 1.30 XTS12 0.00 0.32 0.64 0.07 1.03 XTS13 0.00 0.19 0.19 0.02 0.41 XTS14 0.01 0.44 0.66 0.05 1.17

394

FeT (wt%) 1.28 1.25 1.22 1.41 1.40 1.73 2.01 2.69 1.94 2.61 1.56 1.46 0.81 1.49

FeHR/FeT 0.67 0.67 0.70 0.54 0.57 0.71 0.73 0.93 0.78 0.83 0.83 0.70 0.50 0.78

Fepy/FeHR 0.08 0.01 0.05 0.01 0.00 0.05 0.09 0.07 0.06 0.02 0.13 0.17 0.08 0.16 0.15 0.18 0.47 0.50 0.46 0.42 0.24 0.22 0.02 0.22 0.01 0.11 0.02

Fepy/FeHR 0.00 0.01 0.01 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.01 0.01

Deze section, Yunnan Province Fe py Fe carb Sample (wt%) (wt%) DZ0 0.11 1.59 DZ1 0.18 0.19 DZ2 0.40 0.33 DZ3 0.07 0.17 DZ4 0.54 0.26 DZ5 0.01 0.20 DZ6 0.00 0.13 DZ7 0.40 0.63

Fe ox (wt%) 0.23 0.19 0.20 1.25 0.36 0.34 0.75 0.33

Position: N 25°59'50", E 103°35'37" Fe mag FeHR FeT (wt%) (wt%) (wt%) FeHR/FeT 0.00 1.93 0.53 3.63 0.00 0.56 0.54 1.03 0.01 0.94 1.00 0.95 0.02 1.51 1.64 0.92 0.00 1.16 1.13 1.03 0.00 0.55 0.55 1.00 0.02 0.90 1.03 0.87 0.01 1.36 1.28 1.06

Fepy/FeHR 0.06 0.32 0.42 0.05 0.46 0.01 0.00 0.29

Meishucun section, Yunnan Province Fe py Fe carb Fe ox Sample (wt%) (wt%) (wt%) KY1 1.70 0.69 0.03 KY2 1.35 0.51 0.05 KY3 0.71 0.48 0.05 KY4 1.15 0.45 0.05 KY5 0.84 0.56 0.05 KY6 1.32 0.36 0.05 KY7 0.78 0.47 0.05 KY8 0.61 0.51 0.05 KY9 0.79 0.46 0.06 KY10 1.28 0.76 0.13 KY11 0.69 0.21 0.14

Position: 24°43'51.46"N, 102°33'58.62"E Fe mag FeHR FeT (wt%) (wt%) (wt%) FeHR/FeT 0.00 2.43 2.22 1.09 0.03 1.94 2.28 0.85 0.06 1.30 2.17 0.60 0.08 1.73 2.71 0.64 0.08 1.53 2.74 0.56 0.11 1.84 3.29 0.56 0.10 1.41 2.68 0.53 0.11 1.28 2.36 0.54 0.11 1.41 2.83 0.50 0.13 2.30 3.07 0.75 0.16 1.20 1.45 0.82

Fepy/FeHR 0.70 0.70 0.55 0.66 0.55 0.72 0.55 0.48 0.56 0.56 0.57

395