21 Fossil fuels, ore and industrial minerals

1

21

Fossil fuels, ore and industrial minerals H. G. DILL, R.F. SACHSENHOFER, P. GRECULA, ´ RI, L. A.PALINKASˇ, S. BOROJEVIC´-SˇOSˇTARIC´, T. SASVA S. STRMIC´-PALINKASˇ, W. PROCHASKA, G. GARUTI, F. ZACCARINI, D. ARBOUILLE and H.-M. SCHULZ

The mining of metallic and non-metallic commodities in Central Europe has a history of more than 2000 years. Today mainly non-metallic commodities, fossil fuels and construction raw materials play a vital role for the people living in Central Europe (Table 21.1). Construction raw materials, albeit the most significant raw material, are not considered further here; for details refer to thematic maps issued by local geological surveys and comprehensive studies such as the textbook by Prentice (1990). Even if many deposits in Central Europe, especially metallic deposits, are no longer extensive by world standards, the huge number and variety of deposits in Central Europe is unique and allows the student of metallogenesis to reconstruct the geological history of Central Europe from the Late Precambrian to the Recent in a way best described as ‘minerostratigraphy’. The term ‘deposit’ is used in this review for sites which were either mined in the twentieth century or are still being operated. A few sites that underwent exploration or trial mining have also been included in this study to clarify certain concentration processes. They are mentioned explicitly in the text to avoid confusion with real deposits. Tonnage and grade are reported in the text only for the most important deposits. Production data for the year 2003 are listed in Table 21.1 for the countries under consideration. In the present study, Central Europe covers the Variscan core zones in the extra-Alpine part of Central Europe stretching from eastern France (Massif Central) into Poland where the contact between the Variscan orogen and the Baltic Shield is concealed by a thick pile of platform sediments. In north–south direction, Central Europe stretches from central Denmark to the southern boundary of the Po Plain in Italy, making the entire Variscan Foreland Basin, the Alpine Mountain Range, the Western Carpathians and the North Dinarides part of the study area. An outline of the geological and geographical settings is shown in Figure 21.1. The precise geographical position of mineral sites, wells of special interest, hydrocarbon provinces, oil shale deposits and coal fields may be deduced from Tables 21.2 to 21.11 and the map ‘Mineral and energy resources of Central Europe’, on a scale 1:2 500 000 (see CD inside back cover). Many deposits were mined for different commodities during different time periods. In the text the various types of mineralization of each deposit are described to give a complete picture of the concentration process through time. In the map (see CD inside back cover), however, each deposit is attributed to that group of commodities for which it was operated for the longest time or for which it is currently mined. The history of the accumulation of ores, industrial minerals

and fossil fuels in Central Europe can be subdivided into two principal phases: the first spans the time period from the Late Proterozoic to the Late Palaeozoic, and the second the epoch from the Late Palaeozoic to the Cenozoic. The first phase is considered as the Variscan cycle, although it includes some deposits of older orogenies, the second is representative of the Alpine cycle. Both cycles overlap slightly. The Variscan metallogenetic cycle fades out with collision-related deposits and the collapse of the Variscan craton during the Late Palaeozoic, while the Alpine cycle commences with coeval intracontinental riftrelated deposits. Those Late Palaeozoic deposits with a great affinity to compressional tectonics are grouped under the heading of the Variscan cycle, whereas those largely related to extensional regimes belong to the Alpine cycle. There are marked structural and geomorphological differences between the Alpine mountain belt in the southern part of Central Europe and its extra-Alpine northern part. In terms of metallogenesis these differences are minor. Indeed, deposits of Variscan age form an integral part of the metallogenic evolution of the Alpine belt. Furthermore, deposits of Alpine age are found also in the Variscan Basement of the extra-Alpine part of Central Europe (Petraschek 1963; Bernard et al. 1976; Baumann 1979; Pouba & Ilavsky´ 1986; Walther 1982; Jaffe´ 1986; Dill 1989; Walther & Dill 1995). Metallogenesis in Central Europe has been studied by many researchers, particularly for the great variety of epigenetic deposits, which made the area a textbook example of vein-type ore mineralization (see Schneiderho¨hn 1962, and references therein). In the early 1970s, a tremendous change in the conception of ore formation occurred. Many deposits, notably in the Alpine region, that were formerly interpreted as epigenetic, were re-interpreted as strata-bound and time-bound (Tufar 1972; Maucher 1974). Classification of mineral and energy resources may be performed in different ways. The traditional classification scheme is based on mineral commodities, metal groups or mineral associations. This approach is suitable for standalone mineral resource maps, for papers satisfying the special demands of economic geologists and mining engineers, and for monograph series such as ‘The Iron Ore Deposits of Europe’ (Zitzmann 1977). However, the mineral associations in Central Europe are highly variable in time and space and were used for different commodities during different time periods. Thus, a subdivision according to commodities (e.g. ores, industrial minerals, fossil fuels) would cause numerous repetitions. To avoid this and in view of the structure of this book, the geological timescale and the geodynamic setting are

The boxed numbers in the margins refer to the numbered list at the end of the chapter

Article number = C21

2 Table 21.1 Production figures of Central European countries for 2003 (Weber & Zsak 2005). Last column shows the share of the world production. No data were available for Bosnia and Herzegovina. Note that only part of the French, Italian and Yugoslavian production is from the area under consideration. All numbers are in metric tons, except where indicated. Austria

Metallic ores Copper Lead Zinc Iron Manganese Tungsten Gold (kg) Silver (kg) Cadmium Gallium Bauxite Uranium Evaporites Potash (K2O) Salt (all types) Gypsum, Anhydrite

Croatia

Czech Denmark Republic

France

Germany

Hungary

Italy

Netherlands

Poland

Slovakia

Slovenia

Yugoslavia

730 28 000

50 000 900

100 331 766 525

429

109 506 478 796

199 000 41 000 421 000

(Moler) 231 000m3 75 000 720 000

914 100

340 000

490 000 33 289 2 840 3 600 000

750 000 359 000

1 014 133 18 500

3 700 40 000

15 000 280 000

28 000 2 500

2 000 000 62 000

146 000

1 300

340 000 33 000

60 000 10 400 137 596

800

167 679 932

130 000 130 000

779 000

280 3 900 8 500

569 000 77 000 181 000

52 4 900

22 000 900 000 17 200

60 000 73 000 76 000

2 000

60 300 11 500

14 000 65 000 940

100 150 000

4 000 6 700 74 000

70 90

900 1 000

950

2 250 4 900 1 000 167 28 000

1 028 273 1 003 550

Fossil Fuels Hard Coal Lignite 1 152 389 2 030 Natural Gas (mio. m3 ) Oil 1 014 716 Oil Shale 432

Switzerland 300 000 18 000 300 000 230 000

2 700 900 000

600 35 000 280

356 1 561 000 150

6 300 000

540

174 000 20

104

104 000

80 000 560 000 3 900 000 4 500 000

3 563 000 16 308 000 1 800 000

170 000

62 000

3 800 000 5 500 000 1 400 000

13 382 000 2 050 000 25 684 000 667 000 50 390 000 380 000 179 085 000 12 692 000 131 8 000 1 300 20 910 3 100 310 000 18 000 000 1 400 000 3 808 946 1 100 000 13 000 295 853

240 000 13 500 72 800 6 000 000 3 100 000 23 200

3 180 000 1 052 000 97 274 000 60 923 000 4 916 753 260

94 000 115 000

4 273

3 600 000 4 828 499 215 49 50 000 526

12 000 36 000 90 000 42 000 000 700 830 000

%

0.0 3.2 10.1 11.5 39.6 4.1 06 20.3 14 2 3.2 6.6 8.6 4.8 2.9 2.1 0.1 0.1 3.2 0.3 8.5 4.2 21.4 0.5 1.6 13.2 16.6 11 2 3.5 40.5 5.1 1.0 2.3

H. G. DILL ET AL.

Industrial minerals Asbestos Barite Bentonite Diatomite Feldspar Fluorite Graphite Kaolin Magnesite Perlite Sulphur (all types) Talc

Belgium

FOSSIL FUELS, ORE AND INDUSTRIAL MINERALS 3

Fig. 21.1. Map showing some major geographical and geological units in Central Europe (the area north of Hannover–Warsaw is not shown). Abbreviations: C.B.P., Central Bohemian Pluton; C.B.S.Z., Central Bohemian Shear Zone; MCG, Mu¨nchberg Gneiss Complex.

4

H. G. DILL ET AL. Table 21.2. Estimated reserves and cumulative production in Central European basins (according to IHS Energy 2004). Estimated total recoverable reserves Oil (MMbl) Baltic Syneclise Northwest European Basin Lower Saxony Basin Paris Basin Upper Rhine Graben Alpine Foreland Basin Carpathian Foreland and Flysch Belt Vienna Basin Pannonian Basin Po Basin Province

480 5700 1930 309 110 150 CZ: 70 PL: 140 980 2500 460

Fields/ discoveries

Gas (Bscf) 340 220 000 32 900 116 50 2300 372 6700 4500 15 500 24 700

101 .1000 283 82(12) 56 193 43 219 148 550 329

Cumulative production

Oil (MMbl)

Gas (Bscf)

250 3800 1750 260 80 137 17 130 780 1930 300

20 132 000 12 600 80 40 1700 70 4000 3000 9000 16 000

Bscf, billion standard cubic feet; MMbl, million barrels.

Table 21.3 Iron–manganese deposits (see CD inside back cover) Number 1 2 3 4 5 6a 6b 6c 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40

Deposit

Element association

Age of formation

Romane`che-Thorins (F) Change (F) Ougney (F) De´le´mont (CH) Herznach (CH) Gutmadingen (D) Geislingen (D) Aalen (D) Eisenbach (D) Saar District (D) Lorraine – Luxembourg (F/L) Namur- Liege (B) Eifel (D) Waldalgesheim (D) Bieber (D) Lindener Mark (D) Lahn-Dill area – Wald-Erbach- Mosel Syncline – Dollendorf Syncline (D) Siegerland-Wied (D) Laisa near Battenberg (D) Adorf (D) Ruhr (D) Hu¨ggel (Massif of Bramsche, Vlotho, Uchte) (D) Damme (D) Nammen (D) Staffhorst (D) Achim (D) Gifhorn (D) Peine-Bu¨lten-Lengede (D) Salzgitter (D) Elbingerode – Zorge (D) Zorge- St. Andreasberg (D)

Mn (F) Fe Fe Fe Fe Fe Fe Fe Fe-(F-Ba) Fe Fe Fe Fe Mn-Fe Fe-Mn-Bi-Co-Ni-(Ba) Mn-Fe Fe

Jurassic ? Jurassic Jurassic Eocene Jurassic Jurassic Jurassic Jurassic Alpine Carboniferous-Permian Jurassic Devonian Devonian Tertiary Alpine Tertiary Devonian

Fe-(Mn-Pb-Cu-Zn-Bi-Sb) Mn-Fe Fe Fe Fe-Pb-Zn Fe Fe Fe Fe Fe Fe Fe Fe-(Fe sulphides) Fe (with Se-bearing veins near Zorge and Tilkerode) Fe Fe-Ba-Cu-Bi-Co-Ni Fe-Ba-Cu-Bi-Co-Ni Fe Fe-(P) Fe Fe (W) Fe-(P) Fe-(P) Fe Fe-(P)

Variscan Carboniferous Devonian Carboniferous Alpine Cretaceous Jurassic Jurassic Tertiary Jurassic Cretaceous Cretaceous Devonian Variscan

Lerbach (D) Schmalkalden (D) Kamsdorf-Saalfeld (D) Schleiz (D) Schmiedefeld-Wittmannsgereuth (D) Arzberg-Tro¨stau (D) Gleißinger Fels, Rotenfels (D) Pegnitz/Auerbach (D) Amberg-Sulzbach-Rosenberg (D) Bodenwo¨hr Embayment (D) Ejpovice- Krusˇna´ Hora- Nucˇice- Zdice- Mnı´sˇekKoma´rov (CZ)

Devonian Alpine Alpine Devonian Ordovician Cambrian Post-Permian Jurassic/Cretaceous Cretaceous Jurassic Ordovician ( continued)

FOSSIL FUELS, ORE AND INDUSTRIAL MINERALS

5

Table 21.3. ( continued) Number

Deposit

Element association

Age of formation

41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109

Moravsky´ Krumlov (CZ) Jesenı´ky Mts. (CZ) Sˇumperk (CZ) Kudowa (PL) Zˇelezny´ Brod (CZ) Kowary (PL) Me˛cinka (PL) Cze˛stochowa – Zawiercie (PL) Da˛browa (PL) Parczo´w-Białaczo´w-Konskie-Przytyk (PL) Le˛czyca (PL) Fyledalen (S) Krzemianka (PL) Ste˛pina (PL) Gorlice - Cieklin - Jasło area (PL) Rajbrot (PL) Wisńiowa (PL) Rudnˇany - Poraćˇ - Bindt - Ra´ztoky (SK) Gelnica - Slovinky (SK) Medzev-Jedl’ovec (SK) Rozˇnˇava (SK) Rudabańya (H) Sˇankovce - Licince (SK) Zˇeleznı´k - Hra´dok (SK) Nizˇna´ Slana´ - Kobeliarovo (SK) Kisˇovce - Sˇva´bovce (SK) Kosćielisko - Dolina Lejowa (PL) Za´zriva´ (SK) Trˇinec - Cieszyn (CZ/PL) Frensˇtat p.Radhosˇtem area (CZ) Lednicke´ Rovne´ (SK) Borinka (SK) Epleńy (H) ´ rku´t (H) U ˇ evljanovicí (BiH) C Varesˇ (BiH) Kljucˇ (BiH) Omarska(BiH) Tomasˇica (BiH) Ljubija- Adamusˇa-Brdo- Atlijina kosa (BiH) Tomasˇica (HR) Gradski potok (HR) Majdan (HR) Gvozdansko (HR) Zˇirovac (HR) Buzˇim (BiH) Bukovica (HR) Medvednica Mt. (HR) Ivansˇcˇica Mt. (HR) Pitten (A) Arzberg (A) Grillenberg (A) Schendleck-Hirschwang (A) Kaskogel Großveitsch (A) Gollrad (A) Erzberg (A) Radmer (A) Waldenstein (A) Wo¨lch /St. Gertraud (A) Kathal (A) Hu¨ttenberg (A) St. Martin am Silberberg (A) Olsa (A) Eino¨d/Friesach (A) Nußdorf (A) St. Nikolai (A) Innerkrems-Altenberg (A) Raggabach (A) Strubberg (A)

Fe Fe Fe Fe Fe Fe-(Bi-Co-Ni) Fe-(Mn) Fe Fe Fe Fe Fe Fe-Ti Fe Mn-Fe-Mg Fe Fe Fe-Cu-Hg- Ba Fe-Cu Fe Fe-Cu-Ag Fe, Cu-Pb-Zn Fe Fe Fe-(Hg) Mn Fe-Mn Mn Fe Fe Mn Mn Mn Mn Mn Fe- Ba-Pb-Zn Fe Fe Fe Fe-(Ba-Pb-ZnF) Fe-(Cu- Pb- Ni-Co) Fe-Cu Fe-Pb Fe Fe Mn Fe -Ba Fe-Mn-Ba Mn-Fe Fe Fe Fe Fe Mn Fe Fe Fe Fe Fe Fe Fe Fe Fe Mn Fe Fe Fe Fe Mn

Proterozoic Devonian+Variscan Proterozoic Post-Permian Proterozoic - Early Palaeozoic Proterozoic + Variscan Variscan Jurassic Post-Devonian Jurassic–Cretaceous Jurassic Jurassic Precambrian Early Cretaceous Early Eocene Early Cretaceous Early Cretaceous Permian Permian Permian Permian Triassic Early Triassic Permian Permian Eocene Triassic–Early Jurassic Jurassic Cretaceous–Early Eocene Cretaceous–Early Eocene Jurassic Jurassic Jurassic Jurassic Triassic Triassic Devonian (?) Variscan Alpine (Permian ?) Alpine (Permian ?) Alpine (Permian ?) Alpine (Permian) Alpine (Permian) Alpine (Permian) Alpine (Permian) Alpine (Permian) Triassic Alpine (Permian–Triassic) Variscan Triassic pre-Alpine Permian Permian Permian pre-Alpine pre-Alpine Permian Permian Tertiary Tertiary Tertiary Tertiary Tertiary Tertiary pre-Alpine Tertiary Tertiary ? pre-Alpine Jurassic ( continued)

6

H. G. DILL ET AL.


Deposit

Element association

Age of formation

110 111 112 113 114 115 116 117 118 119 120 121 122 123

Hochkranz (A) Teisenberg (D) Gru¨nten (D) Gonzen (CH) Oberhalbstein (CH) Val Ferrera (CH) Alfredo-S. Aloisio (I) Erzegg (CH) Chamoson (CH) Mont Chemin (CH) Praborna (I) Cogne (I) St. Georges d9Hurtie´res (F) Gambatesa (I)

Mn Fe Fe Mn-Fe Mn Mn-Fe Fe Fe Fe Fe Mn Fe Fe-Cu Mn

Jurassic Eocene Eocene Jurassic Jurassic Jurassic Lower Triassic Jurassic Jurassic Variscan Jurassic–Cretaceous Jurassic–Cretaceous Variscan Jurassic–Cretaceous

Table 21.4. Bi–Co–Ni–Ti–Cr–PGE deposits (see CD inside back cover) Number

Deposit

Element association

Age of formation

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32

Wittichen (D) Freudenstadt (D) Neubulach (D) Weilburg-Odersbach (D) Bad Liebenstein (D) Harzburg (D) Midlum (D) St. Egidien (D) Sohland-Sˇluknov (D, CZ) Krˇemzˇe (CZ) Stare´ Ransko (CZ) Szklary (PL) Ta˛padła (PL) Dobsˇina (SK) Hodkovce (SK) Szarvasko˝ (H) Brezik, Tadicí, Konjuh Mt. (BiH) Ozren Mt. (BiH) Ozren Mt. (BiH) Borja Mt. (BiH) Gornje Oresˇje, Medvednica Mt. (HR) Kraubath (A) Hochgro¨ßen (A) Schladming (A) Leogang (A) Totalp (CH) Poschavio (CH) Palagnedra (CH) Kaltenberg (CH) Campello Monti (I) Gula (I) Scopello (I)

Bi-Co-Ni-U-F-Ba Bi-Co-Ni-Ba Bi-Co-Ni-Ba Ni-Cu Bi-Co-Ni Ni-Cu Ti -(Zr) Ni Ni Ni Ni-Cu-Zn Ni Cr Ni-Co-Fe-Cu-(asbestos) Ni-Co-Cr Fe-Ti Ni-Co Cr-(magnesite) Ni Cr Ni Cr Cr Ni-Co-Zn Ni-Co-Hg-Cu Ni Ni Ni Ni-Co Ni Ni Ni

Variscan–Alpine Alpine Alpine Lower Carboniferous Alpine Carboniferous Pliocene Cretaceous–Tertiary (Palaeogene) Variscan Tertiary Proterozoic (–Cambrian?) Tertiary (Miocene) Early Devonian Variscan (Triassic) Cretaceous–Tertiary Jurassic Cretaceous–Tertiary Jurassic Cretaceous Jurassic Cretaceous Pre-Variscan Variscan Pre-(?)Variscan Early Palaeozoic Jurassic Jurassic Late Palaeozoic Permian Alpine Late Palaeozoic Permian Late Palaeozoic Permian Late Palaeozoic Permian

used as the principal classification criteria. This classification provides a direct link to the stratigraphy-orientated chapters of this book so that mineralogical and chemical concentration processes are embedded into the geodynamic evolution of the Central European crust. Further subdivision is based on the particular element or mineral assemblages present in the deposits. In the following sections, the mineralization processes and the resultant deposits are subdivided into six first-order categories:

(1) (2) (3) (4)

strata-bound deposits; thrust-bound metamorphogenic and/or fold-related deposits; deposits controlled by collision-related granitic activity; unconformity-related fault-bound hypogene and supergene deposits of Early and Late Alpine age; (5) deposits controlled by extension-related igneous activity along deep-seated fault zones; (6) petroleum deposits.


7

Table 21.5. Sn–W–U–Nb–Ta–Li–Mo deposits (see CD inside back cover) Number

Deposit

Element association

Age of formation

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69

Chateau Lambert (F) St. Hippolyte (F) Breitenbach (F) Framont-Grandfontaine (F) Schelingen-Kaiserstuhl (D) Menzenschwand (D) Wittichen (D) Mu¨llenbach (D) Ellweiler (D) Burgsandstein-Stubensandstein area (D) Schwarzach Area (D) Hagendorf- Pleystein-Waidhaus (D) Dylen (CZ) Ma¨hring (D) Poppenreuth (D) Zadnı´ Chodov (CZ) Vı´tkov (CZ) Falkenberg Granite (D) Weißenstadt (D) Gra¨fenthal Horst (D) Grossschloppen (D) Hebanz (D) Mo¨schwitz (D) Gera-Ronneburg area (D) Schneeberg (D) Hartenstein (D) Aue (D) Schwarzenberg (D) Jaćhymov (CZ) Hornı´ Slavkov (CZ) Tipersdorf (D) Zobes (D) Pechtelsgru¨n (D) Zschorlau (D) Gottesberg-Mu¨hlleiten (D) Rotava (CZ) Krasno (CZ) Breitenbrunn-Po¨hla (D) Ehrenfriedersdorf (D) Verˇnerˇov (CZ) Sadisdorf (D) Altenberg (D) Zinnwald-Cıńovec (D/CZ) Krupka (CZ) Teplice (CZ) Pirna (D) Ko¨nigsstein (D) Hamr (CZ) Nove´ Meˇsto pod Smrkem (CZ) Giercyn - Krobica (PL) Zo´lkiewka (PL) Obrˇ´ı Du˚l (CZ) Kowary (PL) Kletno (PL) Prˇ´ıbram (CZ) Okrouhla´ Radounˇ (CZ) Dobra´ Voda (CZ) Jihlava (CZ) Hornı´ Babakoc (CZ) Rozˇna´ (CZ) Olsˇ´ı (CZ) Scheibengraben (CZ) Novoveska´ Huta (SK) Hnilec-Medvedı´ potok - Dlha´ Dolina (SK) Rochovce (SK) Vikartovce-Spisˇsky´ Sˇtiavnik (SK) Jasenie-Kysla´ (SK) Ka´lnica (SK) Cer Mt. (SCG)

Mo U Mo Fe-W Nb U U-Bi-Co-Ni U U U U Li-feldspar-quartz-phosphate U U U U U U Sn-W U-(Fe /see ‘‘Ockerkalk’’) U U U U U U-(Hg) U U U-Ag-Bi-Co-Ni Sn-W-U W W W W W-Sn W Sn-W Sn-W Sn Sn-Li Sn Sn Sn-W-Li Sn U U U U Sn-Co Sn-Co Nb-Ta W U U U U Li Li W U-Li U Be-Nb-Ta U-Mo-Cu Sn(-REE) Mo-W U W-Au-As U Nb-Ta-W-Sn-fluorite

Variscan Alpine Variscan Variscan Tertiary Variscan Variscan, Alpine Alpine Alpine Triassic Variscan Variscan Variscan Variscan Variscan Variscan Variscan Variscan, Alpine Variscan–Quaternary Variscan (Silurian), Alpine Variscan Variscan Variscan, Alpine Variscan, Alpine Variscan Variscan Variscan Variscan Variscan Variscan Variscan Variscan Variscan Variscan Variscan Variscan Variscan Variscan Variscan Variscan Variscan Variscan Variscan Variscan Cretaceous Cretaceous Cretaceous Cretaceous Variscan Variscan Variscan Variscan Variscan Variscan Variscan Variscan Variscan Variscan Variscan Variscan Variscan Variscan Permian Variscan–Alpine Variscan–Alpine Variscan Variscan Variscan Oligocene ( continued)

8

H. G. DILL ET AL.


Deposit

Element association

Age of formation

70 71 72 73 74 75 76 77 78

Ninkovacˇa creek (HR) Ko˝vago´szo˝lo˝s – Bakonya (H) Prinzenkogel (A) Weinebene (A) Zˇirovski Vrh (SLO) Pusterwald (A) Mallnock (A) Forstau (A) Mittersill (A)

U U U Li U Li W U W

79 80 81 82 83 84 85 86 87

Novazza-Val Vedello (I) Mu¨rtschenalp (CH) Trun (CH) Naters (CH) Ise´rables (CH) Le Chatelard (CH) Grange Serre Preit (I) Rio Freddo Peveragno (I) Bric Colme’ Pamparato (I)

U U-Cu U U U U U U U

Silurian–Devonian Permian Permian Permian Permian Permian Alpine? Permian Pre-Variscan (Cambrian) to Variscan (Carboniferous) Alpine Permian Variscan Variscan Permian Variscan Permian Permian Permian

Table 21.6. Sb–Au–Hg–As deposits (see CD inside back cover) Number

Deposit

Element association

Age of formation

1 2 3 4 5 6 7 8 9 10a 10b 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41

Genf-Allondon (CH) Napf (CH) St. Ulrich-Sulzburg (D) Silberwald (F) Charbes (F) Rheingold (D) Stahlberg (D) Landsberg – Obermoschel (D) Hohes Venn (D) Bru¨ck a. d. Ahr (D) Goesdorf (L) Rauppach (Apollo Mine) (D) Arnsberg (D) Korbach-Goldhausen (D) Eder (D) Wolfsberg (D) Schwarza (D) Schleiz-Greiz-Wolfersgru¨n (D) Brandholz-Goldkronach (D) Luby (CZ) Kasˇperske´ Hory (CZ) Kasejovice (CZ) ˇ elina (CZ) Novy´ Knıń - Psı´ Hory – Mokrsko -C Milesˇov Kra´sna Hora (CZ) Jı´love´ (CZ) Roudny (CZ) Wlen´ (PL) Złoty Stok (PL) Dubnı´k-Mernı´k (SK) Telkibańya (H) Zlata´ Idka (SK) Du´brava - Magurka (SK) Medzibrod-Dolna´ Lehota (SK) Klokocˇ - Kalinka (SK) Malachov (SK) Kremnica (SK) Vyhne (SK) Nagybo¨rzso¨ny (H) Zlatnı´ky (SK) Pezinok (SK) Klı´zˇska Nema´ (SK) Zajacˇa (YU)

Au Au Sb (+Ag) Sb Sb Au Hg Hg Au Sb Sb Sb Sb Au Au Sb Au Sb Au-Sb Hg Au-Pb Au Au Au-Sb Au-Cu-Ag-Sb-As Au Au-As Au-As Hg Au-Ag Sb-Au Sb-Au Sb-Au Au Hg Au-Ag-Sb Au-Ag-Sb, Fe Au-Ag-Pb-Cu Au Sb-Au-As/Fe suphides Au Sb- As- Pb- Cu-Zn

Quaternary Tertiary–Quaternary Variscan-(Alpine) Variscan Variscan Quaternary Alpine Alpine Variscan Variscan Variscan Variscan Variscan Alpine Quaternary Variscan Quaternary Variscan Variscan Variscan Variscan Variscan Variscan Variscan Variscan Variscan Variscan Variscan Neogene Miocene Variscan Variscan Variscan Neogene Neogene Neogene Neogene Miocene Quaternary Variscan Quaternary Oligocene ( continued)


9


Deposit

Element association

Age of formation

42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76

Stolice(YU) Krupanj (YU) Drazˇevicí (BiH) Hrmza (BiH) Bakovicí (BiH) Fojnica(BiH) Vrtlasce (BiH) ˇ emernica (BiH) C Mid-Bosnian Schist Mts. (BiH) Trsˇcé, Gorski kotar region (HR) Idrija (SLO) Schlaining (A) Tallackkogel (A) Flatschach (A) Kliening-Kothgraben (A) Pusterwald (A) Schellgaden (A) Rotgu¨lden (A) Gastein/Rauris (A) Fusch (A) Stockenboi (A) Siflitz (A) Glatschach (A) Rabant (A) Calanda (CH) Astano (CH) Val Toppa (Pieve Vergonte) (I) Maglioggio-Alfenza Crodo (I) Gondo (CH) Mottone (Antronapiana) (I) Pestarena-Macugnana (I) Kreas, Alagna (I) Brusson (I) Salanfe (CH) La Gardette (F)

Sb- As- Pb- Cu-Zn Sb- As- Pb- Cu-Zn Hg Hg-As-Ba Au - Fe sulphide Au-Fe-Sb-As-Ba-Pb-Cu As-Fe-Zn-Pb-Sn-Mo-Cu-Bi Sb-As-Hg-Fe- Zn-Cu Au-As-Sb-Hg-Fe- Ba-Cu Hg Hg Sb Hg Au Au- As Au Au-W Au- As- Bi Au Au Hg Au Hg Sb Au Au-As-Sb Au Au Au-Ag Au Au Au Au Au Au

Oligocene Oligocene Triassic Permo-Carboniferous Permo-Carboniferous Permo-Carboniferous Permo-Carboniferous Permo-Carboniferous Permo-Carboniferous Triassic Triassic Miocene Alpine Alpine Alpine ? Pre-Alpine–Alpine Alpine Alpine Alpine Alpine Alpine Alpine Alpine Late Alpine Variscan ? Variscan ? Tertiary (Oligo-Miocene) Tertiary (Oligo-Miocene) Tertiary (Oligo-Miocene) Tertiary (Oligo-Miocene) Tertiary (Oligo-Miocene) Tertiary (Oligo-Miocene) Variscan Late Alpine

Deposit

Element association

Age of formation

Sain Bel (F) Chessy (F) Giromagny (F) Sainte-Marie-aux-Mıˆnes, La Croix aux Mines (F) Schauinsland (D) (+vein-type deposits in the environs of St. Blasien, Mu¨nstertal) Badenweiler (D) Wiesloch (D) Fischbach (D) Tellig - Altlay (D) Werlau (D) Lohrheim (D) Holzappel (D) Ems - Braubach (D) Mu¨hlenbach (D) Rheinbreitbach (D) Bleialf - Rescheid (D) Maubach - Mechernich (D) Aachen - Moresnet (D, B) Erkelenz (D) Bensberg (D) Velbert Anticline (D) Ruhr-District (D) Iserlohn - Schwelm (D) Meggen (D) Ramsbeck (D)

Cu-Fe sulphide Zn-Cu-Ba Pb-Zn Pb-Zn-Bi-Co-Ni Pb-Zn

Devonian Devonian Alpine Alpine Alpine

Pb-Zn Zn-(Pb) Cu Pb-Zn Pb-Zn Fe sulphide-Ba Pb-Zn Pb-Zn Pb-Zn Cu Pb Pb-Zn Pb-Zn Pb-Zn Pb-Zn Pb-Zn Pb-Zn Zn Fe sulphide-Zn-Pb-Ba Pb-Zn

Alpine Alpine Alpine (Permian) Variscan Variscan Devonian Variscan Variscan Variscan Alpine Alpine Alpine (Triassic) Alpine Alpine Variscan Alpine Alpine Alpine Devonian Variscan

Table 21.7. Pb–Zn–Cu–Fe sulphide–Ba deposits (see CD inside back cover) Number 1 2 3 4 5a 5b 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

( continued)

10

H. G. DILL ET AL.


Deposit

Element association

Age of formation

25 26 27

Marsberg (D) Helgoland (D) Rammelsberg (D)

Permian–Alpine Triassic Devonian

28

Cu Cu Zn-Pb-Cu- Fe sulphide Ba(Ag-Au) Pb-Zn

Grund (D) (+ Oberharz vein-type deposits near Clausthal-Zellerfeld, Lautenthal, St. Andreasberg) Mansfeld-Sangerhausen (D) Cu-(Ag) Richelsdorf (D) Cu Wallenfels-Du¨rrenwaid-Remschlitz (D) Pb-(Zn) Kupferberg-Wirsberg-Sparneck-Neufang (D) Cu (Zn) Fe sulphides Waldsassen-Bayerland (D) Fe sulphide-Zn Weiden Embayment-Freihung (D) Pb-(Mn) Erbendorf (D) Pb-(Zn) Lam (D) Fe sulphide Bodenmais area (D) Fe sulphide Struhadlo-Klatovy (CZ) Fe sulphide-(Cu-Zn) Prˇ´ıbram(CZ) Pb-Zn-U Strˇ´ıbro (CZ) Pb-Zn Olovı´ (CZ) Pb-Zn Klingenthal (D) - Tisova´ (CZ) Fe sulphide-Cu Prˇ´ısecˇnice - Meˇdeneˇc (CZ) Fe- Sn-Cu Annaberg - Marienberg (D) Pb Hermsdorf - Elterlein - Lengefeld - Jahnsbach (D) Pb-Zn Mikulov (CZ) Pb-Zn Freiberg-Halsbru¨cke (D) Pb Kutna´ Hora (CZ) Pb-Zn-Sb-Ag Chvaletice - Hromnice (CZ) Fe sulphide-Mn Nowa Ruda (PL)-Hornı´ Vernerˇovice (CZ)-Okrzeszyn Cu (PL) N Sudetian Basin, Konrad - Lena (PL) Cu Pre-Sudetian Block Polkowice - Lubin (PL) Cu Miedzianka - Stara Go´ra (PL) Cu-Zn Wiesćiszowice (PL) Fe sulphide Zlate´ Hory (CZ) Zn-Pb-Cu-Au-Ag Hornı´ Benesˇov, Hornı´ Me˘sto, Oskava (CZ) Fe sulphide-Pb-Zn Upper Silesia: Bytom-Tarnowskie Go´ry-OlkuszZn-Pb Zawiercie (PL) Zawiercie (PL) Zn-Pb Pilica (PL) Cu Dolina Bedkowska (PL) Cu Karczo´wka-Kielce (PL) Pb(-Zn) Łago´w (PL) Pb(-Zn) Rudki (PL) Fe sulphide Zlata´ Banˇa (SK) Cu-Pb-Zn (Au-Ag) Brehov (SK) Cu-Pb-Zn (Au-Ag) Smolnı´k- Mnı´sˇek nad Hnilcom (SK) Cu-Fe sulphides Recsk (H) Cu-Zn (Mo-Au) Gyo¨ngyo¨soroszi (H) Pb-Zn L’ubietova´ SK) Cu Sˇpania Dolina (SK) Cu Banska´ Sˇtiavnica-Hodrusˇa-Pukanec (SK) Cu-Pb-Zn (Au-Ag) Zlatno (SK) Cu-Pb-Zn-Mo (Au) Pa´tka – Szu¨zva´r (H) Zn-Pb-Mo-fluorite Srebrenica (BiH) Pb-Zn-Ag-Au-Cu-Cd-Sb-As Olovo (BiH) Pb-Zn Srednje (BiH) Pb-Zn-Ba Veovacˇa (BiH) Pb-Zn-Ba Borovica (BiH) Pb-Zn-Ba Rupice (BiH) Pb-Zn-Ba Ribnica-Maglajac-Kamenac, Krivaja river valley (BiH) Cu Srb, Lika region (BiH) Pb-Zn ˇ avka Mt. (BiH) C Cu Svinica, Petrova gora Mt. (HR) Pb-Zn Rude, Samoborska gora Mt. (HR) Fe-(Ba-Cu- Pb-Zn- Ba) Sv. Jakob, Medvednica Mt. (HR) Pb-Zn Ivansˇcˇica Mt. (HR) Pb-Zn Litija (SLO) Cu-Pb-Zn- Sb-Hg- Ba-Fe Sˇkofje (SLO) Cu Mezˇice (SLO) Pb-Zn

29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89

Alpine Permian–Alpine Alpine Alpine Early Palaeozoic (Ordovician) Cambrian Alpine (Triassic) Alpine Precambrian–Cambrian Precambrian–Cambrian Precambrian–Cambrian Variscan-(Alpine) Variscan-(Alpine) Alpine Cambrian (Proterozoic) Variscan Alpine Cambrian Variscan (Proterozoic) Variscan Variscan Precambrian–Cambrian Permian–Alpine Permian–Alpine Permian–Alpine Variscan Precambrian Devonian Devonian Triassic–Alpine Variscan Variscan Variscan Alpine Triassic–Alpine Variscan Neogene Neogene Silurian-Devonian Neogene Miocene Variscan Variscan Neogene Neogene Eocene Oligocene Triassic Triassic Triassic Triassic Triassic Jurassic Triassic Jurassic Triassic Permian Triassic Triassic Permian Permian Triassic ( continued)


11


Deposit

Element association

Age of formation

90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132

Topla (SLO) Arzberg-Graz Palaeozoic (A) Oberzeiring (A) Meiselding (A) Walchen (A) Bleiberg (A) Raibl (I) Rauschberg (D) Ko¨nigsberg (D) Mitterberg (A) Grossfragant (A) Salafossa (I) Kitzbu¨hel (A) Schwaz (A) Lafatsch (A) Ho¨llental (D) Saüling (A) Monteneve (I) Montafon (A) Bleiberg (CH) Silberberg (CH) Ba¨renbu¨hl (CH) Alp Taspin (CH) Alp Nade´ls (CH) Bristenstock (CH) Val Seriana, Val Brembana (I) Agogna-Motto-Piombino (I) Migiandone-Ornavasso (I) Trachsellauenen (CH) Goppenstein (CH) Grimentz (CH) Praz Jean-St. Luc (CH) Promise La Thuile (I) Peisey (F) La Plagne (F) L9Argentie`re-la-Basseé (F) Menglon (F) Saint Ve´ran (F) Le Cerisier (F) Valauria (F) Libiola (I) Vigonzano (I) Bisano (I)

Pb-Zn Pb-Zn Pb-Zn (Ag- Ba) Pb-Zn Cu Pb-Zn Pb-Zn Pb-Zn-(Fe sulphide) Pb-Zn-(Fe sulphide) Cu, Ni Cu Zn-Pb Cu-Ba Cu- Ag-Ba Pb-Zn Pb-Zn-(Mo) Fe sulphide-Zn-Ba- limonite Zn-Pb Cu-Fe-Au Pb-Zn Pb-Zn Pb-Zn Pb-Zn Pb-Zn Pb-Zn Pb-Zn Pb-Zn-(Ag) Cu Pb-Zn-(Ba) Pb-Zn-(Ba-F) Cu-Bi-Ag Pb-Zn Pb-Zn Pb-Ag Pb-Ag Pb-Ag Zn-Pb Cu Cu Pb-Zn Cu-Fe sulphide Cu-Fe Cu

Triassic Palaeozoic Late Alpine Palaeozoic Alpine Triassic Triassic Triassic Triassic Alpine Triassic Triassic Alpine Palaeozoic Triassic Triassic Triassic Pre-Variscan Permian Triassic Triassic Triassic Alpine Variscan ? Variscan Triassic Variscan Pre-Variscan Alpine Alpine Alpine Alpine Alpine? Lower Triassic Lower Triassic Lower Triassic Alpine? Jurassic–Cretaceous Lower Triassic Alpine Jurassic–Cretaceous Jurassic–Cretaceous Jurassic–Cretaceous

Deposit

Mineral association

Age of formation

Les Baux (F) Saint-Bauzile (F) Larnage (F) Antully (F) Maine (F) Courcelles (F) Faymont-Val d9 Ajol (F) Maxonchamp (F) Mu¨nstertal (D) Oberwolfach-Clara (D) Ka¨fersteige (D) Neuhu¨tten (D) Vogelsberg (D) Usingen (D) Lahn (D) Geisenheim, Diez, Niederdresselndorf (‘‘Westerwald Kaolin’’) (D) Rohberg near Wiesbaden (D)

Bauxite Diatomite Kaolin Fluorite Fluorite Fluorite-barite Fluorite-barite Fluorite Fluorite-barite Barite- fluorite-(Ag) Fluorite-(barite) Barite Bauxite Quartz Phosphorite Kaolin

Cretaceous Neogene Eocene (?) Liassic Liassic Liassic Alpine Alpine Alpine Alpine Alpine Alpine Tertiary Alpine Tertiary Tertiary

Barite

Devonian

Table 21.8 Industrial minerals deposits (see CD inside back cover) Number 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17

( continued)

12

H. G. DILL ET AL.


Deposit

Mineral association

Age of formation

Barite Kaolin-(feldspar) Barite Kaolin Phosphorite Phosphorite Phosphorite Barite Barite Barite Barite Quartz Kaolin Barite Calcite Barite (Co-Ni) Barite-fluorite Barite Barite-fluorite (Fe-Mn)

Alpine Permian Devonian Tertiary Cretaceous Cretaceous Cretaceous Alpine Alpine Alpine Variscan (Devonian) (Alpine ?) Tertiary Tertiary Alpine (Post-Jurassic) Alpine Alpine Alpine Alpine Alpine

Quartz Celestite Quartz Diatomite Diatomite-bentonite Bentonite Kaolin Amber Phosphorite Amber Amber Fluorite-barite Kaolin Kaolin Kaolin Kaolin Kaolin Quartz Fluorite Fluorite Barite Talc Feldspar-quartz Kaolin Talc (soapstone) Kaolin Coloured clay Feldspar Coloured clay Quartz-feldspar-kaolin Fluorite-(barite) Barite-(fluorite) Fluorite Quartz Asbestos Kaolin

Cretaceous Jurassic Cretaceous Quaternary Eocene Tertiary Pre-Lower Cretaceous Tertiary-Quaternary Tertiary Tertiary Tertiary Alpine Cretaceous–Tertiary Cretaceous–Tertiary Cretaceous–Tertiary Cretaceous–Tertiary Cretaceous–Tertiary Tertiary Alpine Alpine Alpine Variscan Variscan Triassic Permian Tertiary Tertiary Variscan Tertiary Triassic Alpine Alpine Alpine Variscan Proterozoic Carboniferous

70 71 72a

Baumholder-Wolfstein (D) Nohfelden (D) Eisen (D) Haut-Fays Baudour (B) Ciply (B) Rocour (B) Vierves-sur-Viron (B) Ava-et-Auffe (B) Fleurus (B) Chaudfontain (B) Cologne Basin (D) Oberwinter (D) Dreislar (D) Brilon-Thu¨len (D) Richelsdorf (D) Ruhla, Steinach, Trusetal (D) Lauterberg (D) Rottleberode Mining District (Stolberg, StraßbergIlfeld mines) (D) Haltern (D) Hemmelte (D) Weferlingen (D) Hetendorf-Lu¨neburg (D) Moler Jutland Peninsula (DK) Friedland (D) Ro¨nne (DK) Darlowo (PL) Leba (PL) Sztutowo (PL) Jantarnj (RU) Ilmenau (D) Halle a.d. Saale (D) Merseburg (D) Kemmlitz (D) Meißen (D) Kamenz – Bautzen (D) Hohenbocka (D) Lichtenberg-Issigau-Lobenstein (D) Scho¨nbrunn-Bo¨senbrunn-Wiedersberg (D) Brunndo¨bra (D) Schwarzenbach a.d. sa¨chs. Saale (D) Mu¨nchberg Gneiss Complex (D) Kronach (D) Go¨pfersgru¨n (D) Tirschenreuth (D) Pegnitz (D) Pu¨llersreuth (D) Neukirchen (D) Hirschau-Schnaittenbach (D) Nabburg-Wo¨lsendorf (D) Nittenau (D) Donaustauf (D) Pfahl (D) Hoher Bogen (D) Plzenˇ Mining District with mines at Kazneˇjov, Hornı´ Brˇ´ıza and Chlumcˇany (CZ) Karlovy Vary - Podborˇany (CZ) Rokle-Kadanˇ (CZ) Hradisˇte (CZ) - Niederschlag-Marienberg (D)

Carboniferous Tertiary Alpine

72b 72c 73 74 75 76 77 78

Moldava - Vrchoslav (CZ) Jı´love´ (CZ) Neuburg a.d. Donau (D) Landshut (D) Kropfmu¨hl (D) ˇ erna´ (CZ) C ˇ esky´ Krumlov (CZ) C Mittergallsbach (A)

Kaolin Bentonite Fluorite-barite (bi-co-ni) Fluorite-barite Fluorite-barite Tripolite Bentonite Graphite Graphite Graphite Phosphorite

18 19 20 21 22 23 24 25a 25b 25c 25d 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69

Alpine Alpine Cretaceous Tertiary Proterozoic Proterozoic Proterozoic Tertiary ( continued)


13


Deposit

Mineral association

Age of formation

79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104

Linz-Plesching (A) Weinzierl-Kriechbaum (A) Mu¨hlberg (A) Limberg-Oberdu¨rnbach (A) Retz – Znojmo (CZ) Ivancˇice (CZ) Javorka (CZ) Krˇisˇany (CZ) Rozdroze Izerskie (PL) Harrachov (CZ) Berzdorf (D) Czerwona Woda (PL) Zebrzydowa (PL) Stanisławo´w-Boguszo´w (PL) Zaro´w (PL) Sobo´tka (PL) Wyszonowice (PL) Szklary (PL) Braszowice (PL) Nowa Ruda (PL) Kletno (PL) Stare´ Meˇsto (CZ) Radzionko´w (PL) Burzenin (PL) Chmielnik (PL) Staszo´w-Tarnobrzeg-Lubaczo´w-Swoszowice-Posa˛dzaCzarkowy (PL) Da˛browa Tarnowska (PL) Mielec – Kolbuszowa (PL) Radom - Annopol (PL) Micho´w – Branica (PL) Leszczawka (PL) Miedzybrodzie (PL) Jaworze (PL) Polany (PL) Majerovce-Nizˇny´ Hrabovec (SK) Pozdisˇovce-Michalovce (SK) Lastovce-Kuzmice (SK) Fu¨ze´rradvany (H) Pa´lha´za (H) Ma´d-Koldu (H) Ma´d-Kira´lyhegy (H) Bomboly (H) Bodrogkeresztu´r Kakas (H) Erdo˝beńye (H) Ma´d-Szegilong (H) Kosˇice (SK) Panˇovce (SK) Drienovec (SK) Sˇvedla´r (SK) Drnava (SK) Gemerska´ Poloma (SK) Maluzˇina´ (SK) Jelsˇava (SK) Hnu´sˇt’a (SK) Breznicˇka-Polta´r(SK) Toma´sˇovce – Halicˇ (SK) Pincina´ (SK) Mocˇiar (SK) Stara´ Kremnicˇka-Jelsˇovy´ potok-Kopernica (SK) Bartosˇova Lehoˆtka (SK) Mojtıń (SK) Smolenice (SK) Posˇtorna (CZ) Istenmezeje (H) Nemti (H) Szurdokpu¨spo¨ki (H) Romhańy (H) Felso˝peteńy-Bańk (H)

Phosphorite Kaolin Graphite Diatomite Kaolin Bentonite Fluorite-barite Fluorite(-barite) Quartz Fluorite-Pb Bentonite Kaolin Kaolin Barite-fluorite Kaolin Magnesite Kaolin Magnesite Magnesite Bauxite Fluorite Graphite Bentonite Phosphorite Bentonite Sulphur

Tertiary Tertiary Proterozoic Tertiary Tertiary Miocene Alpine Alpine Variscan ? Variscan–Alpine Tertiary Cretaceous Cretaceous Alpine ? Cretaceous–Tertiary Devonian Tertiary Devonian Devonian Carboniferous Alpine Proterozoic Upper Carboniferous Cretaceous Tertiary (Tortonian) Tertiary

Kaolin Kaolin Phosphorite Phosphorite Diatomite Bentonite Bentonite Bentonite Zeolite Kaolin/halloysite Bentonite Mica (illite) Perlite Kaolin Bentonite-allevardite-alunite Dickite Zeolite Diatomite Kaolin-bentonite Magnesite Asbestos Bauxite Quartz Barite Talc Barite Magnesite Talc Kaolin Kaolin Diatomite Diatomite Bentonite Kaolin Bauxite Barite Illite Bentonite Zeolite Diatomite Kaolin Kaolin

Miocene Miocene Cretaceous Cretaceous Oligocene–Miocene Palaeogene Miocene Palaeogene Neogene Pliocene Miocene Miocene Miocene Miocene Miocene Miocene Miocene Miocene Miocene Permian Triassic Cretaceous Alpine Variscan Alpine Variscan Permian Alpine Pliocene Pliocene Neogene Neogene Miocene Pliocene Late Cretaceous Variscan Neogene Miocene Neogene Miocene Oligocene Oligocene

105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146

( continued)

14

H. G. DILL ET AL.


Deposit

Mineral association

Age of formation

147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215

Nagyegyha´za (H) Gańt (H) Iszkaszentgyo¨rgy (H) Fenyo˝fo˝ (H) Dudar (H) Zirc – Also´perepuszta (H) Halimba – Szo˝c (H) Iharku´t – Nyira´d (H) Su¨meg (H) Cserszegtomaj (H) Zlatibor-Varda (BiH) Vlasenica (BiH) Zvornik (BiH) Krivaja-Konjuh Mt. (BiH) Musˇicí, Ozren Mt. (BiH) Zˇarkovac, Ozren Mt. (BiH) Bosansko Petrovo Selo, Ozren Mt. (BiH) Gracˇanica (BiH) Tesˇani (BiH) Jajce (BiH) Babicí, Jajce (BiH) Baracˇi (BiH) Dalmatia, Herzegovina (HR; BiH) Kijak, Dinara Mt., Dalmatia (HR) Gracˇac, Lika region (HR) Vrace, Lika region (HR) Obrovac, Dalmatia (HR) Divoselo (HR) Grmecˇ Mt. (BiH) Bosanska Krupa, Grmecˇ Mt. (BiH) Zˇune (Dolinac) (BiH) Vidrenjak (BiH) Ljesˇani- Bosanski Novi (BiH) Kozara-Pastirevo (BiH) Banja Luka-Prnjavor (BiH) Motajica Mt. (BiH) Kaptol-Sivornica- Brusnik (HR) Dukina Kosa (HR) G. Jelenska (HR) Kijak (HR) Gejkovac (HR) Kordun (HR) Lokve (HR) Mrzle vodice (HR) Sˇkolski Brijeg (HR) North Adriatic islands (HR) Rovinj (HR) Vrsar (HR) Istria (HR) Central and NW Slovenia deposits (SLO) Hrusˇica (SLO) Kamnik (SLO) Zˇuzˇemberk (SLO) Poljanska Luka (HR) Bednja-Sˇasˇa (HR) Stainz (A) Rutzendorf (A) Gossendorf (A) Schlaining (A) Aspang (A) Eichberg/Weißenbach (A) Semmering (A) St. Jakob (A) Rabenwald (A) Steg/Anger (A) Großveitsch (A) Breitenau (A) Mixnitz (A) Aflenz (A)

Bauxite Bauxite Bauxite Bauxite Bauxite Bauxite Bauxite Bauxite Bauxite Kaolin/coloured clay Magnesite Bauxite Bentonite Magnesite Talc Talc Asbestos (chrysotile) Bentonite Bentonite Bauxite Bentonite Bauxite Bauxite Bauxite Barite Bauxite Bauxite Bentonite Bauxite Bauxite Barite-fluorite Barite Bentonite Magnesite Magnesite Kaolin-feldspar-quartz Graphite Feldspar-mica Bentonite Barite Barite Bauxite Barite Barite Barite Bauxite Bauxite Bauxite Bauxite Bauxite Bauxite Bauxite Bauxite Bentonite Bentonite Bentonite Bentonite Bentonite Asbestos Mica Magnesite Barite Talc-chlorite Talc Feldspar Magnesite Magnesite Phosphorite Diatomite

Eocene Eocene Eocene Eocene Eocene Cretaceous Cretaceous–Eocene Cretaceous–Eocene Late Cretaceous Cretaceous Jurassic Cretaceous Miocene Jurassic Jurassic Jurassic Jurassic (Oligocene?) Miocene Miocene Cretaceous Miocene Tertiary Tertiary Cretaceous Carboniferous Triassic Tertiary Miocene Jurassic Cretaceous Permian Permian Miocene Jurassic Jurassic Eocene–Oligocene Ordovician–Silurian Devonian–Carboniferous Miocene Permian Permian Cretaceous Permo-Triassic Permo-Triassic Permo-Triassic Tertiary Jurassic Jurassic Tertiary Tertiary Jurassic Triassic Jurassic Miocene Miocene Miocene Miocene Miocene Alpine Cretaceous Permian Permian Cretaceous Cretaceous Variscan Permian Permian Pleistocene Miocene ( continued)


15


Deposit

Mineral association

Age of formation

216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265

Oberdorf (A) Gams (A) Gams (A) Unterlaussa (A) Kaisersberg (A) Mautern (A) Wald/Schober (A) Trieben/Sunk (A) Trieben (A) Lassing (A) Weisskirchen (A) Fohnsdorf (A) Hirt (A) Radenthein (A) Edling/Spital (A) Hochfilzen (A) Achselalm (A) Go¨sleswand (A) Hollenzen (A) Wolfendorn (A) Corvara (I) Case a Prato (I) Vallarsa (I) Zumpanell (I) Vignola (I) Vegri-Campotamaso (I) Marigole-Pice (I) Torgola (I) Pozzuolo (I) Valle di Meraldo, Gardena, Monte Elto (I) Laghetto di Polzone (I) Scortaseo (CH) Ruola (I) Val Brembana (I) Camissinone (I) Le Trappistes (CH) Baldissero (I) Balangero (I) Termignon (F) Icla Brutta Comba (I) Rocheray (¼Bois Feuillet) (F) Rochefort-Samson (F) Hostun (F) Berbie´res (F) Condorcet (F) Mormoiron (F) Apt (F) Tapets (F) Manosque (F) Perticara (I)

Magnesite Jet Fluorite Bauxite-jet Graphite Talc Magnesite Graphite Magnesite Talc Mica Bentonite Talc Magnesite Feldspar Magnesite Fluorite-(Pb-Zn) Asbestos Asbestos Kyanite Fluorite-(Pb-Zn) Fluorite-(barite-Pb) Fluorite Magnesite Fluorite-(Cu-Pb-Zn) Bentonite Barite Fluorite Barite Barite Fluorite Talc Barite Fluorite Fluorite Fluorite Magnesite Asbestos Asbestos Graphite Fluorite-(Pb) Quartz-kaolin Kaolin-quartz Kaolin-quartz Celestite-barite Bentonite-attapulgite Coloured clay Sulphur Sulphur Sulphur

Permian Cretaceous Alpine Cretaceous Alpine Cretaceous Permian Alpine Permian Cretaceous Cretaceous Miocene Alpine? Permian Variscan Permian Alpine Alpine Alpine Alpine Alpine (Permian?) Permian Permian Triassic Alpine (Permian?) Cretaceous? Alpine (Permian) Alpine (Permian) Triassic Triassic Triassic Jurassic–Cretaceous Triassic Triassic Triassic Alpine Pleistocene Alpine Upper Jurassic–Cretaceous Carboniferous Alpine Eocene Eocene Eocene Alpine Oligocene Cenomanian Oligocene Oligocene–Miocene Miocene

This classification scheme is well-established for the extraAlpine part of Central Europe (e.g. Dill 1988a, 1989, 1994; Dill & Nielsen 1987; Tischendorf et al. 1995) and is extended in the present review to the Alpine realm, where similar subdivisions have been applied by Pohl (1993), Pohl & Belocky (1999) and Rodeghiero et al (1996). Categories 1 to 5 reflect extensional and compressional regimes and their resultant igneous activity, as well as uplift and erosion during the late stages of the Variscan and Alpine orogenies. The formation of petroleum deposits (6) requires a wide range of processes (e.g. deposition of source and reservoir rocks, trap formation, petroleum generation and migration) which may occur during different times and in different tectonic

regimes, even within a single basin. Therefore, petroleum deposits do not fit into any of the first five categories and form a separate sixth category. Cross-sections of typical deposits of categories 1 to 3 are shown in Figure 21.2. The complex geological setting of unconformity-related deposits is illustrated in a set of idealized cross-sections in Figure 21.3. Figure 21.4 presents the Kaiserstuhl Nb-bearing carbonatite in the Upper Rhine Graben as a representative of category 5. Cross-sections through petroliferous basins are portrayed in the relevant sections. Modern radiometric age dating (e.g. Wernicke & Lippolt 1997a) has allowed the Alpine unconformity-related deposits to be subdivided into two age groups. The older one encompasses Upper

16

H. G. DILL ET AL.

Table 21.9. Evaporite deposits (see CD inside back cover) Number

Deposit

Element association

Age of formation

1 2 3 4 5 6 7 8 9 10 11 12a 12b 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50a 50b 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67

Hauterives (F) Etrez (F) Perrigny (F) Poligny (F) Arc-et-Senans-Besancon (F) Rheinfelden (CH) Zurzach (CH) Rheinheim (D) Mulhouse (F) Buggingen (D) Stetten (D) Nancy - Dombasle (F) Dieuze (F) Jemeppe (B) Heilbronn (D) Bad Friedrichshall-Kochendorf (D) Philippshall - Bad Du¨rkheim (D) Bad Mu¨nster am Stein (D) Bad Kreuznach (D) Neuhof Ellers (D) Merkers (D) Unterbreizbach (D) Hattorf - Unterbreizbach (D) Springen (D) Wintershall (D) Oberilm (D) Kassel-Wilhelmsho¨he (D) Bad Karlshafen (D) Go¨ttingen-Grone (D) Sollstedt (D) Volkenroda-Pa¨thess (D) Sonderhausen (D) Bleicherode (D) Bischofferode (D) Roßleben- Georg-Unstrut (D) Halle a.d. Saale (D) Bernburg-Gro¨hna (D) Staßfurt (D) Scho¨nebeck-Salzelmen (D) Zielitz (D) Bartensleben-Marie (D) Braunschweig-Lu¨neburg (D) Hildesheimer Wald (D) Lehrte-Sehnde (D) Wathlingen (D) Bokeloh (D) Borth (D) Hengelo (NL) Epe (D) Weerselo Overijssel, NE Hengelo (NL) Zuidwending Groningen (NL) Veendam Groningen (NL) Harlingen (NL) Winschoten Groningen (NL) Harsefeld (D) Stade (D) Hvornum (N of border of the map - DK) Lu¨neburg (D) Bad Su¨lze (D) Kolobrzeg (PL) Leba (PL) Nowa So´l (PL) Mogilno (PL) Inowrocław (PL) Kłodawa (PL) Barycz (PL) Wieliczka (PL) Łe˛z˙kowice-Siedlec (PL) Bochnia (PL)

Na Na Na Na Na Na Na Na K K Na Na Na Na Na Na Na Na Na K-Mg K-(Na-Br) K K-Na-Mg K-(Br) K Mg Na Na Na Na K K K-(Br) K K K Na Na Na-K K-Na K-Na Na Na K-Mg-Br K-Mg K-Na K Na Na Na Na Na Na-K-Mg Na Na Na Na, Na-K Na Na Na Na-K Na-K Na Na Na Na Na Na Na

Eocene?–Oligocene Eocene–Oligocene Upper Triassic Upper Triassic Upper Triassic–Neogene Middle Triassic Middle Triassic Triassic Neogene Palaeogene Middle Triassic Upper Triassic Upper Triassic Zechstein Middle Triassic Middle Triassic Neogene? Palaeogene Palaeogene Zechstein Zechstein Zechstein Zechstein Zechstein Zechstein Zechstein Zechstein Zechstein Zechstein Zechstein Zechstein Zechstein Zechstein Zechstein Zechstein Zechstein Zechstein Zechstein Zechstein Zechstein Zechstein Zechstein Zechstein Zechstein Zechstein Zechstein Zechstein Lower Triassic Zechstein Zechstein Zechstein Zechstein Zechstein Zechstein Zechstein Zechstein Zechstein Zechstein Zechstein Zechstein Zechstein Zechstein Zechstein Zechstein Zechstein Miocene Miocene Miocene Miocene ( continued)


17


Deposit

Element association

Age of formation

68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83

Tarno´w-Sierakowice (PL) Zbudza (SK) Sol’ (SK) Presˇov-Sol’na´ Banˇa (SK) Tuzla (BiH) Altaussee (A) Bad Ischl (A) Sulzbach (A) Hallstatt (A) Roßalm (A) Du¨rrnberg/Hallein (A) Berchtesgaden (D) Rosenheim (D) - Traunstein (D) Bad Reichenhall (D) Hall in Tirol (A) Bex (CH)

Na Na Na Na Na Na Na Na Na Na Na Na Na Na Na Na

Miocene Miocene Miocene Miocene Miocene Permian Permian Permian Permian Permian Permian Permian Permian Permian Permian Triassic

Table 21.10. Hydrocarbon provinces (see CD inside back cover) Number

Hydrocarbon province

1

Northwest European Basin Southern Permian Basin Thuringian Basin Mecklenburg District Pommerian District Lusatian - Fore-Sudetic District Zielona Go´ra Trough Poznan Trough West Netherlands Basin Broad Fourteens Basin Southern Central Graben Lower Saxony Basin Gifhorn Trough Hamburg Trough Heide Trough East Holstein Trough Baltic Syneclise Paris Basin Upper Rhine Graben Alpine Foreland Basin Carpathian Foreland and Carpathian Flysch Belt Vienna Basin Po Basin Pannonian Basin Sava Depression Drava Depression Zala Basin Danube Basin Great Hungarian Plain East Slovak Basin

1a 1a-1 1a-2 1a-3 1a-4 1a-5 1a-6 1b 1c 1d 1e 1f 1g 1h 1i 2 3 4 5 6 7 8 9 9a 9b 9c 9d 9e 9f

Carboniferous to Lower Jurassic vein mineralization immediately below the Variscan unconformity and epigenetic deposits in overlying sediments. These deposits are termed ‘Early Alpine unconformity-related’. In contrast, ‘Late Alpine unconformityrelated’ deposits include Upper Jurassic to Cenozoic epigenetic mineralization. Each of the following sections starts with a brief discussion of the geodynamic setting providing a framework for the understanding of ore-forming processes. More detailed compilations are given in the relevant chapters of this book. The country of

each mining site or mineralized area is given in parentheses, using the common international abbreviation: Austria (A), Belgium (B), Bosnia-Herzogovina (BiH), Croatia (HR), Czech Republic (CZ), Denmark (DK), France (F), Germany (D), Hungary (H), Italy (I), Lithuania (LT), Luxembourg (L), the Netherlands (NL), Poland (PL), Romania (RU), Slovakia (SK), Slovenia (SLO) Spain (E) Switzerland (CH), Yugoslavia (Serbia and Montenegro) (YU).

Variscan cycle Strata-bound deposits Precambrian-Cambrian Several Palaeozoic plates, including Gondwana and Baltica, originated from the Late Proterozoic breakup of the Rodinia supercontinent. Apart from the Eastern European Craton (EEC), which formed part of Baltica, the area of today9s Central Europe was located at the active northern margin of Gondwana, where it became affected by the Neoproterozoic Cadomian Orogeny (e.g. Tait et al. 2000; Winchester et al. 2002; Krawczyk et al. 2008). During Cambrian times, initial rift zones became apparent along the north Gondwana margin. However, only a few crustal blocks (e.g. Małopolska Terrane) rifted away from Gondwana and docked the EEC. Thus, the majority of the pre-Variscan relicts in Central Europe remained near Gondwana and were characterized by the formation of oceanic crust, island arcs, and the deposition of carbonates and volcanosedimentary rocks in arc-related basins (Neubauer et al. 1999; von Raumer et al. 2002, 2003). Evidence of Precambrian metallogenesis can be found mainly in the Bohemian Massif. In the Tepla´-Barrandian Zone of the Bohemian Massif the Neoproterozoic/Cambrian boundary is marked by an angular unconformity between Neoproterozoic basement rocks and transgressively overlying Lower Palaeozoic sedimentary and volcanosedimentary sequences (Chlupaćˇ et al. 1998). Irrespective of the unconformity, Precambrian and Cambrian strata-bound deposits are dealt with together, since the type of mineralization is similar. Moreover, due to the poor age data of the host rocks, a clear attribution to one or the other period is often impossible. The Moldanubian Zone in the Bohemian Massif is subdivided from base to top into the Ostrong (¼ Monotonous), Drosendorf

18

H. G. DILL ET AL.

Table 21.11. Coal deposits (see CD inside back cover)

Table 21.11. ( continued)

Carboniferous coal deposits

Neogene coal deposits

C1a C1b C2 C2a C3 C4 C5 C6 C7 C8 C9 C10 C11 C12 C13 C14 C15 C16 C17 C18 C19 C20 C21 C22 C23 C24 C25a C25b C26 C27 C28 C29

N1 N2 N3 N4 N5 N6 N7 N8 N9 N10 N11 N12 N13 N14 N14a N14b N14c N14d N14e N15 N16 N17 N18 N19 N20 N20a N20b N21 N22 N23 N24 N25 N26 N27 N28 N29 N30 N31 N32 N33 N34 N34a N34b N35 N36 N37 N38 N39 N40 N41 N42 N43 N44 N45 N46 N47 N48 N49 N50 N51 N52 N53

Wallonian Basin (Hainault; B) Wallonian Basin (Liege; B) Aachen – South Limburg (D, NL) Aachen – Erkelenz (D) Campine Basin (B) Ruhr (D) Winterswijk (NL) Ibbenbu¨ren (D) Saar-Lorraine (D, F) Sincey (F) Blanzy (F) Autun (plus oil shales) (F) St. Etienne (F) La Mure (F) La Thuile (I) Lons-le-Saunier (F) Ronchamp (F) St. Hippolyte (F) Baden-Baden (D) Stockheim (D) Manebach (D) Ilfeld (D) Wettin (D) ¨ lsnitz (D) Zwickau-O Freital (D) Doberlug (D) Western Bohemian Basin (CZ) Central Bohemian Basin (CZ) Lower Silesian Basin (CZ, PL) Rosice – Oslavany (CZ) Upper Silesian Basin (CZ, PL) Lublin (PL)

Mesozoic coal deposits M1 M2 M3 M4 M5 M6 M7 M8 M9

Osnabru¨ck (D) Barsinghausen (D) Zawiercie (PL) Foreland of Łysa Go´ra (PL) Gresten Coal District (A) Lunz Coal District (A) Gru¨nbach (A) Ajka (H) Mecsek (H)

Palaeogene coal deposits P1 P2 P3 P3a P3b P4 P5 P6 P7a P7b P7c P8a P8b P8c P8d P9a P9b

Lower Hesse (Borken – Kassel) (D) Sybhercynian Basin (D) Middle Germany (Halle – Borna) (D) Geiselthal (D) Oberro¨blingen-Amsdorf (D) Upper Bavaria (D) Ha¨ring (A) Herzogenburg – Krems (A) Secovlje (SLO) Vremski Britof (+latest Cretaceous coal) (SLO) Rasa Valley (HR) Zabukovica (SL) Zasavje (Trbovlje – Hrastnik) (SLO) Senovo (SL) Pregrada – Radoboj (HR) Oroszlańy (H) Tatabańya (H)

Lower Rhine Basin (D) Wetterau (D) Rho¨n (D) Hoher Meißner (D) Middle Germany (Leipzig –Bitterfeld) (plus amber) (D) Lower Lusatia (D, PL) Legnica (PL) Poznan (PL) Konin (PL) Adamo´w (PL) Łodz (PL) Bełchato´w (PL) Radom (PL) Eger [Ohrˇe] Graben (D, CZ, PL) Cheb (CZ) Sokolov (CZ) Most (CZ) Zittau (D, PL) Go¨rlitz (D, PL) Oberpfalz (Schwandorf - Wackersdorf) (D) Ka¨pfnach (CH) Trimmelkam (A) Hausruck (A) Langau (A, CZ) Noric Depression (A) Fohnsdorf (A) Leoben (A) Lavanttal (A) Velenje (SLO) Wies – Eibiswald (A) Ko¨flach – Voitsberg (A) Tauchen – Mariasdorf (A) Torony (H) Brennberg (H, A) Zillingdorf – Sollenau (A) Hodonin – Dubrany – Gbely (CZ, SK) Upper Nitra Basin (Handlova´, Novaky´; SK) Va´rpalota (H) No´gra´d - Modry´ Kamen (HU, SK) Borsod (H) Visonta-Bu¨kka´brańy (H) Visonta (H) Bu¨kka´brańy (H) Kocevje (SLO) Globoko (SLO) Konjscina (HR) Ivanec-Varazdin (HR) Pokupsko-Vukomer (HR) Ludbreg-Koprivnica (HR) Bilogora-Podravski B.(HR) Posavje B. (HR) Kamengrad (BiH) Banja Luka (BiH) Tesanj (BiH) Stanari B. (BiH) Gracanica B. (BiH) Kreka – Tuzla (BiH) Banovici (BiH) Central Bosnia (Zenica-Kakanj-Breza; BiH) Ugljevik (BiH) Kolubara (YU) Kostolac (YU)

( continued)

(¼ Variegated) and Gfo¨hl units. The Ostrong Unit is derived from Late Proterozoic-age arenaceous and argillaceous clastic rocks deposited in a shallow-marine rift basin with local placerlike Au concentrations. In contrast an Early Palaeozoic age is

likely for the sedimentary precursors of the Drosendorf Unit whose bimodal volcanic rocks may be assigned to within-plate volcanism (Kroner et al. 2008). The Gfo¨hl Unit is mainly composed of high-pressure granulites.


19

Fig. 21.2. Cross-sections of typical mineral deposits referrred to in the text: (a) strata-bound deposit, e.g. Kupferberg (D), Au-bearing Cu–Zn sulphide deposit (VMS type); (b) strata-bound–stratiform, e.g. Langenbach mining district (D), hematite deposit (Lahn Dill type/SEDEX type); (c) thrust-bound, e.g. Berga Anticline (D), stibnite–quartz veins (type: mesothermal Au–Sb–As vein); (d) granite-related, e.g. Grossschloppen (D), polymetallic U deposit (type: silicified mineralized structure zone and episyenite).

Metallogenesis in Central Europe corresponds to the complex geodynamic evolution at the Proterozoic–Cambrian boundary. Deposits with graphite and Fe, Cu, Zn and Pb sulphides are widespread in the Bohemian Massif (Pouba & Krˇibek 1986). Bathymetric conditions led to the development of dysaerobic to anaerobic depositional environments. In calcareous rocks, base metal and sideritic Fe deposits developed under moderately reducing conditions. Moreover, active continental margin settings formed the basis for one of the most important scheelite deposits, and ophiolitic sequences host a suite of elements such as Cr, Ni and platinum-group elements (PGE) related to basic and ultrabasic igneous rocks.

Graphite and semigraphite deposits. At the southern margin of the Bohemian Massif (Moldanubian Zone; Drosendorf Unit), several graphite deposits occur in the Passau Forest at Kropfmu¨hlPfaffenreuth (D), in Austria (e.g. Mu¨hlberg; closed in 1988), at ˇ erna´ (CZ), Krumlov (CZ), Kolodeˇje nad Luzˇnicı´ (CZ) and Stare´ C Meˇsto (CZ) (Houzar & Nova´k 2002). The sedimentary graphite deposits are, in places, abundant in metaphosphorites. Graphite with low crystallinity (amorphous graphite) and well-crystallized flaky graphite are exploited from lenses intercalated into paragneisses and marbles. Amorphous graphite has also been under exploration in the Moldanubian/Saxothuringian border zone near Tirschenreuth-Ma¨hring (D) (Teuscher & Weinelt 1972).

20

H. G. DILL ET AL.

Fig. 21.3. Unconformity-related deposits. (a) Supergene unconformity-related U deposits in the Gera-Ronneburg mining district (D). Early Palaeozoic ‘low-metal concentrations’ were subject to chemical weathering from the Late Palaeozoic onward. (b) Kupferschiefer-type mineralization above and below the Early Alpine unconformity (model modified from Rentzsch 1974). (c) Schematic cross-section illustrating the genetic relation between post-Variscan vein-type deposits in the folded Variscan basement and arenaceous deposits of Triassic age (Maubach-Mechernich (D)). Lead mineralization forms cement (‘Erzknotten’) of siliciclastics spread across the unconformity/peneplain (model modified from Krahn 1988). (d) Model to show fluid movement and the direction of the sediment dispersal system above the unconformity near the basement edge (Dill & Carl 1987).

Silicate- (and carbonate-) hosted base metal–iron sulphide deposits (VHM, SMS, Kieslager type). A compilation of deposits in the central parts of the Bohemian Massif was provided by Mra´zek (1986) who also demonstrated that the Late Proterozoic metallogeny was related to volcanic and postvolcanic thermal activity. Pyrite and pyrrhotite mineralization with subordinate amounts of Cu and Zn sulphides occur in lowgrade regionally metamorphosed basic and intermediate metavolcanic rocks. A representative of this type of ore deposit is located near Struhadlo/Klatovy (CZ) at the SW edge of the Tepla´Barrandian Zone. It is considered to be equivalent to the modern Cyprus-type ore deposits. Cu–Zn sulphide mineralization in basic and acidic metavolcanites of the Jı´love´ Belt near the boundary between the Tepla´-Barrandian and Moldanubian zones are considered to be genetically equivalent to mineralizations in Archean greenstone belts (Mora´vek & Pouba 1990). A mineralization of Proterozoic age, unique for Central Europe, contains V-bearing garnet, roscoellite, coffinite and

uraninite in silicites covering large areas in the SE and western parts of the Tepla´-Barrandian Zone. Fe content is up to 35% while U and V contents are up to 0.2% (Mra´zek & Pouba 1995). The role of organic matter in the formation of the metal-rich shales in the Late Precambrian Bohemian Massif has been noted by Pasˇava et al. (1996). This strata-bound mineralization is similar to that in Siluro-Devonian black shales (Graptolite Shales) elsewhere in Central Europe in terms of geochemistry and geodynamic setting. A pyrite-bearing mineralization in black shales was mined for Fe–Mn ore by open-pit operation at Chvaletice in the Zˇelezne´ Hory Mountains (CZ) and to produce sulphur for the chemical industry (Pouba & Ilavsky´ 1986). The deposit also contains Mnbearing silicates and carbonates together with Fe sulphides, but Mn could not be won economically. Mn carbonates are associated with coarse-grained clastic rocks attesting to some shallowing of the sea during the Late Precambrian in an otherwise deep-marine basin. Elevated organic matter contents in the


Fig. 21.4. Deposits controlled by extension-related igneous activity along deep-seated fault zones: the carbonatite-hosted Nb deposit in the Kaiserstuhl igneous complex at Schelingen (D) (modified after Keller 1984).

Upper Precambrian sediments were decisive for the concentration of metals, while the metal source is related to submarineexhalative vent systems associated with the aforementioned volcanism. The Drosendorf Unit of the Moldanubian Zone hosts one of the most remarkable mineralizations, the Lam-Bodenmais Kies Belt (D) (Dill 1990a). The last mine was operated for raw materials used in the glass industry for polishing, and ceased production in 1953. These sediment-hosted Fe–Zn–Cu–Pb sulphides show a zonation into a proximal Fe–Zn–Cu association with Fe-enriched sphalerite, argentiferous galena, pyrite and pyrrhotite and a distal Pb–Ba mineralization. Zn concentration involved precipitation of the aforementioned sphalerite, Zn spinel/kreittonite, a black variety of gahnite containing ferrous Fe or ferric Fe, and Zn staurolite. In view of the significant amounts of Ba associated with these deposits and the Pb and S isotopes, these sediment-hosted deposits are classified as Sullivan-type/Meggen-type deposits sensu Krebs (1981), Jiang et al. (1998) and Taylor & Beaudoin (2000). Within the Saxothuringian Zone, stratigraphically higher than the deposits of the Lam-Bodenmais Kies Belt (D), pyrrhotiteand pyrite ore bodies were found in the Fichtelgebirge within paragneisses and mica schists and have been mined between 1923 and 1971 in the Bayerland Mine near Waldsassen (D). Magnetite-bearing layers are abundant in the vicinity and a silica zone was drilled in the footwall of these ore bodies (Wolf 1971; Dill 1989). The host rock sequence was subjected to low- to medium-grade regional metamorphism. Pyrite and pyrrhotite ore bodies are unrelated to the different degrees of metamorphism but are controlled palaeogeographically (Dill 1989). Pyrite is inferred to have been precipitated in a relatively shallow-marine environment, whereas pyrrhotite formed in deeper waters. Re-

21

stricted aeration and a high sulphur partial pressure (PS2 ) in the basin were additional factors responsible for the preservation of organic matter and the concentration of Fe, Cu and Zn sulphides in metamorphosed clastic rocks in the Erzgebirge at Tisova´ (CZ), Klingenthal (D), Elterlein (D), and Jahnsbach (D) (Perthold et al. 1994; Tischendorf et al. 1995; Baumann et al. 2000). In addition to the siliciclastic-hosted Fe deposits, there are also some carbonate-hosted Fe–Zn–Cu–Pb deposits in the Erzgebirge, e.g. Lengefeld (D) and Hermsdorf (D) in the Cambrian Klinovec and Thum Groups. In comparison to the Irish-type or MississippiValley type (MVT) Pb–Zn deposits, the Central European carbonate-hosted Zn–Cu–Pb deposits contain higher amounts of Ag and Sb (Sawkins 1984). These discrepancies between Early and Late Palaeozoic carbonate-hosted Fe–Zn–Cu–Pb deposits may be explained by the higher temperature regime during greenschist metamorphism, which the Central European basemetal deposits were subjected to. ¨ tztal Nappe), the Monteneve/Schneeberg In the Eastern Alps (O mine (I) forms part of a horizon mineralized with Zn–Pb minerals that extends over c. 20 km within paragneisses of preSilurian age (Fo¨rster & Schmitz 1972; Frizzo et al. 1982). The ore bodies contain Cd- and Mn-rich sphalerite and Ag-rich galena, with minor pyrrhotite, chalcopyrite, pyrite and stibnite. Gangue minerals are carbonates, quartz, garnet, amphibole, biotite, chlorite, muscovite, albite and tourmaline. The Monteneve deposit suffered strong metamorphism, that caused deformation, selective remobilization and recrystallization of a precursor sedimentary mineralization. A number of ‘Kieslager’ deposits (Migiandone-Ornavasso (I), Cuzzago (I), Nibbio (I), Val di Mengo (I), Alpe Collio (I)) occur in the middle Val d’Ossola of Piedmont in the Kinzigitic Series of the Ivrea Zone. The ore deposits are associated with amphibolite–granulite facies metasediments and metavolcanics. Pyrrhotite, chalcopyrite, pyrite, sphalerite, ilmenite, titanite, and magnetite form either high-grade disseminated or massive ore bodies within the amphibolite, paragneiss and felsic granulites (Fagnani 1947). The ore mineralization originated from synsedimentary volcanic activity in an oceanic basin which is characterized by MORB-type basaltic magmatism. Carbonate-hosted iron deposits. Fe deposits in the Saxothuringian Zone, closely related to the (Pre-)Cambrian Wunsiedel Marble, have been mined for many decades at various sites in the Fichtelgebirge (e.g. Arzberg (D), Tro¨stau (D)). The origin of the deposits and the age of the calcareous host rock have been hotly debated (e.g. Tischendorf 1986). Some authors suggest that the layered siderite ore bodies are part of the Variscan Fe skarn association, while others consider them to be related to Early Palaeozoic syngenetic siderite mineralization (Horstig & Teuscher 1979; Dill 1985a, 1989). Siderite, the most common mineral in these Lower Palaeozoic rocks, may be encountered either as massive bodies in metacarbonates, far from any granitic intrusion, or disseminated (even in metaclastic rocks) outside of the contact aureole of the granitic intrusions. Judging by the variegated lithology of the host sequence, the Fe-rich calcareous sediments formed on a shelf platform in a dysaerobic environment. As the Eh value was lowered, pyrite replaced siderite. Close to the surface, the sideritic Fe ore was altered into limonite which has been the target of mining. A total of 5 Mt of Fe ore containing 30–50% Fe were extracted until 1905. A re-evaluation of ore reserves during World War II yielded 4.3 Mt of ore. During the Variscan Orogeny Fe, preconcentrated during the Early Palaeozoic, was remobilized from calcareous rocks. In the Zˇelezny´ Brod (CZ) area (West Sudetes), where an Arzberg-type

22

H. G. DILL ET AL.

ore exists, lenses of hematite and magnetite are conformably intercalated among Proterozoic or Lower Palaeozoic calcareous rocks exhibiting low-grade metamorphism (Mochnacka et al. 1995). The West Sudetes form part of the Lugian Zone (eastern part of the Saxothuringian Zone), which is characterized by many strata-bound magnetite, hematite and pyrite deposits related to submarine volcanic rocks. Subsequent regional metamorphism and the lack of reliable age data make any attempt at a minerostratigraphic correlation of these strata-bound ore mineralizations with the rest of the Bohemian Massif very difficult.

2

Tin–tungsten–gold–lead–copper deposits (Freiberg Felsite Horizon and Mittersill type). Pseudo-stratiform concentrations of cassiterite were discovered in the early 1960s in the Upper Proterozoic Freiberg Felsite Horizon (Erzgebirge/Krusˇne´ Hory Mountains; Saxothuringian Zone). A similar type of Sn accumulation was also found in the West Sudetes (Lugian Zone) at Nove´ Me˘sto pod Smrkem (CZ), Giercyn and Krobica (PL). The resources of the deposits at Giercyn and Krobica (PL) were estimated at about 2.9 Mt of ore with an average Sn content of about 0.48% (Polish Geological Institute 2004). Subeconomic cassiterite occurrences are hosted by mica–chlorite schists and accompanied by Fe, Cu, Bi, As, Co, Zn sulphides, scheelite and ferberite (Mochnacka et al. 1995). The rock suite passed through conditions of c. 5208C and 5–6 kbar at some stage during regional metamorphism, although a pre-metamorphic origin for at least some of the sulphides cannot be ruled out (Cook & Dudek 1994). Probably this sulphide-bearing Sn accumulation in Upper Proterozoic metamorphic rocks is the volcanosedimentary ‘protore’ of late Variscan granite-related Sn mineralizations (Baumann 1979). Collomorphous and needle-shaped cassiterite have been precipitated late- to post-kinematically in mylonitic zones in the Erzgebirge, so that this Sn mineralization is categorized as thrust-bound rather than strata-bound. Some authors speculated that hydrothermal activity associated with acid intrusives of the Variscan Karkonosze Pluton had introduced the mineralizing fluids along tectonic lineaments (Speczik & Wiszniewska 1984). Significant W–Au–Cu–Pb mineralizations were formed in island-arc systems (Habach Terrane; Frisch & Neubauer 1989) now exposed in the Tauern Window in the Eastern Alps. Pb isotopes indicate mantle and crustal sources. The two ore fields in the Mittersill (Felbertal) scheelite deposit (A) were discovered in 1967 (Ho¨ll 1975; Ho¨ll & Eichhorn 2001). Since 1975 it has produced some 7 Mt of ore and still produces 400 000 t ore at a grade of 0.5% WO3 annually. According to Eichhorn et al. (1999) the evolution of the Mittersill scheelite deposit commenced with the development of a volcanic arc at c. 550 Ma as indicated by the emplacement of volcanic-arc basalts. Approximately coeval crustal thinning occurred in a backarc region, accompanied by the emplacement of tholeiitic basalts and the intrusion of minor diorites. Subsequently, gabbroic and ultramafic melts intruded into the arc and backarc region followed by normal I-type granitoid melts with mantle signature until 530 Ma. Subsequently, highly differentiated, yet still mantledominated granitic melts were locally intruded between 530 Ma (Eastern Ore Zone) and 520 Ma (Western Ore Zone) in the Mittersill ore deposit. Chromium–titanium–nickel–PGE deposits. Cr and Ni concentrations bound to basic and ultrabasic rocks occur in the Ransko Complex (CZ). Ransko is a strongly differentiated intrusive body of peridotite, troctolites and gabbro undergoing liquid segregation which resulted in the formation of Ni–Cu and

Zn–Cu sulphide concentration (Pouba & Ilavsky´ 1986; Van der Veen & Maaskant 1995; Pasˇava et al. 2003). An Early Cambrian age of the ultrabasic complex has been suggested based on geological and palaeomagnetic studies (Marek 1970). The major minerals are pentlandite, pyrite and chalcopyrite associated with some mackinawite and magnetite, suggesting a Sudbury-type origin (Pouba & Ilavsky´ 1986). Subeconomic Cr and PGE mineralizations occur in the Eastern Alps SW of Leoben at Kraubath (A) in a highly dismembered backarc ophiolite (Speik Terrane) (Malitch et al. 2003). The Krzemianka ilmenite–magnetite deposit is located in NE Poland in the Mazury Complex (Baltic shield; East European Craton). The deposit is related to the Suwałki Anorthosite Massif and is liquid-magmatic in origin (Osika 1976; Wiszniewska 1998). It was discovered in 1962, but did not go into production for environmental reasons. Completely obscured by a Phanerozoic cover, the Suwałki intrusion has been drilled extensively. Isotope analyses were carried out using the Re–Os method for titanomagnetite and sulphide ores from Suwałki which yielded isochron ages of 1559 37 and 1556 94 Ma (Stein et al. 1998a; Wiszniewska 2000; Morgan et al. 2000). Ordovician–Silurian During Early Ordovician time Avalonia, including the Rhenohercynian Zone, began to rift away from Gondwana opening the Rheic Ocean, and collided with the Eastern European Craton and Laurentia during Ordovician/Silurian times (Krawczyk et al. 2008). Drifting of the Armorican Terrane Assemblage and preVariscan relicts in the Alps, which were located in the eastern prolongation of Avalonia, was hampered by a (Proto-Tethyian) oceanic ridge. Instead of drifting, these detached terranes collided with Gondwana during an Ordovician orogeny (von Raumer et al. 2002, 2003). However, the resulting cordillera started to collapse during the Late Ordovician leading to the opening of the Palaeo-Tethys rift and the Late Silurian drift of the Hun-Superterrane comprising, amongst others, the Armorican Terrane Assemblage (including the Saxothurinigan-Lugian, Tepla´-Barrandian and Moldanubian zones) and most pre-Variscan relicts within the Alpine Mountain Range (Neubauer et al. 1999; Jurkovic´ & Pamic´ 2001; Stampfli & Borel 2002; von Raumer et al. 2003). Evidence for Silurian rifting and volcanism is found in the Bohemian Massif, the Eastern Alps, the Western Carpathians and the Dinarides (e.g. Kukal 1985; Grecula et al. 1995; Jurkovic´ & Pamic´ 2001). The Tisza Unit, forming the basement of the southern part of the Pannonian Basin, represents an Early Palaeozoic fragment broken off from the southern margin of Eurasian (Jurkovic´ & Pamic´ 2001). The protolith of regionally metamorphosed sequences, migmatites and granitoids is a series of Silurian– Devonian sedimentary rocks interlayered with basalts that originated along the active Palaeo-Tethyan margin with I-type subduction-related plutonism (Pamic´ & Balen 2001). In the Thuringian–Franconian Massif (Saxothuringian Zone) two different lithofacies types may be found in the Ordovician geological record. At the northern passive continental margin, the Thuringian facies developed, which is dominated by clastic sedimentary rocks and Fe ore in a nearshore marine environment. In contrast, around the Mu¨nchberg Gneiss Complex, volcanic and volcaniclastic rocks, mainly of basaltic and spilitic composition, are interbedded with neritic clastic sediments (Bavarian facies). These rocks occur in a sequence of tectonic units called the Randschiefer, Prasinit-Phyllit and Randamphibolit series, which underwent very low- to medium-grade regional meta-

FOSSIL FUELS, ORE AND INDUSTRIAL MINERALS morphism (Wirth 1978) and were interpreted as tectonic klippen (Franke 1989). The Bavarian facies and its metallogenic inventory (discussed below) is indicative of a geodynamic regime well known from modern active plate margins (Dill 1989). This also has a metallogenetic equivalent in the Lower Austro-Alpine Nappe. The Silurian was a period of worldwide anoxic events favouring the deposition of transgressive black shales (e.g. Cole 1994; Houseknecht et al. 1992; Paris et al. 1986; Xiao et al. 2000). Within Central Europe metalliferous black shales (Graptolite Shales) with a Silurian age are known from the Saxothuriangian Zone, the Barrandian Zone, the Western Carpathians and the Tisza Unit. These black shales are enriched in base metals and rare earth elements all across Central Europe. Shallow-marine limestones interbedded with these black shales host syn- and epigenetic siderite ore.

3

Ironstone deposits (Thuringite/Wabana type). The worldwide deposition of Ordovician ironstones may be traced in the Lower Palaeozoic sedimentary rocks of the Bohemian Massif (Van Houten & Bhattacharyya 1982; Young 1989; Van Houten & Hou 1990). In the Saxothuringian Zone, three seams of Ordovician-age oolithic Fe ores, containing siderite, thuringite, chamosite and magnetite, were formed during transgressions in a shallowmarine environment (Thuringian facies). The upper seam is up to 22 m thick (Bach et al. 1976) and formed the basis for mining operations near Gebersreuth (D), Schmiedefeld (D) and Wittmansgereuth (D). Related exploration was at To¨pen, Bruck and Gra¨fenthal (D) (Reh & Schro¨der 1974; Dill 1985a). These massive beds of oolithic Fe ore are relatively high in P (c. 0.8 wt%) with Fe contents up to 50 wt% in magnetite-enriched beds. Sedimentary Fe deposits of Ordovician age in the Tepla´Barrandian Zone were mined for hematite–siderite ore at Ejpovice and Krusˇna´ Hora (CZ), and for chamosite–siderite ore at Nucˇice and Zdice (CZ) until 1967 (Petrańek 1975; Petrańek & Van Houten 1977; Farshad 2001). The ironstones of the Czech deposits are grey-green in colour and contain ooids, pisoids and peloids. Chamosite is replaced by siderite almost completely at Nucˇice and Chrustinice. Relicts of chamosite may be admixed with high proportions of newly formed kaolinite and quartz (Zdice). At Nucˇice, pyrite framboids are strongly enriched together with magnetite, graphite, organic material, zircon, anatase and sulphides (galena, sphalerite, marcasite, chalcopyrite) (Farshad 2001). Based on chemical composition, ore textures and lithofacies, these Ordovician-age Fe ores were attributed to the well-known Wabana type (Ranger 1979). The 18 O values of mineral pairs from the Fe deposits yield calculated palaeotemperatures of c. 238C. The epoch appears to have been characterized by atmospheric partial pressure of carbon dioxide (PCO2 ) values which were 16–18 times higher than the present-day ones. The association of comparatively low tropical temperatures (and an icesheet at high palaeolatitude) with high atmospheric PCO2 might have been a result of lower solar luminosity in the Late Ordovician (Yapp 1991, 1998). Gold-bearing copper–zinc–iron sulphide deposits (volcanic massive sulphide (VMS) type). In Lower Palaeozoic rocks of the Bavarian facies (Fichtelgebirge; Saxothuringian Zone), stratiform ore bodies with pyrrhotite, pyrite, chalcopyrite, sphalerite and rare magnetite occur at Neufang and Sparneck (D) in the Prasinit-Phyllit Series and at Kupferberg (D) in the Randschiefer

23

Series. The latter series is lithologically similar to the PrasinitPhyllit Series, yet did not reach greenschist metamorphic conditions (Fig. 21.2a). The element composition of the ore includes Fe, Zn, and Cu, but no significant quantities of Pb. Au is present in amounts up to 2 ppm (Urban & Vache 1972). There is a striking difference between the S isotopes of the volcanic-hosted base-metal deposits of the Kupferberg-type and the sedimenthosted sulphide deposits at Waldsassen (D) previously discussed. Base-metal concentration is confined to bimodal volcanic and volcaniclastic host rocks of calc-alkaline affinity, so that the deposits of the Kupferberg–Neufang–Sparneck mineral belt are tentatively attributed to the Besshi-type deposits that reflect a subduction-related metallogenic setting (Hutchinson 1980; Fox 1984). Within the Alpine region, some Austro-Alpine amphibolite/ ¨ tztal, Kreuzeck Mountains (A)) contain gneiss complexes (O stratiform polymetallic (Fe–Cu–Zn–Pb) mineralizations which were most probably formed in backarc settings (e.g. Raggabach (A)). The isotope Pb signatures are typical for continental environments (Ebner et al. 2000). Graphite/meta-anthracite and oil shale deposits. In the Psunj Mountain (HR) (Tisza Unit) metasediments undergoing Barrovian-type metamorphism are interbedded with seams of graphite and (?)meta-anthracite (Sˇinkovec & Krkalo 1994). Several mines at Kaptol (HR), Sivornica (HR) and Brusnik (HR) were in operation. The total production was about 22 000 t of ore with 45–70% C. The reserves were estimated at 60 000 t (Sˇinkovec & Krkalo 1994). Uraniferous polymetallic deposits (black shale type). Black shales in the Papuk Mountains (Tisza Unit) contain economic U concentrations. At Ninkovacˇa creek (HR) the low-grade metamorphic Radlovac Series contains 0.04% U3 08 with reserves of 15 t U3 O8. The U mineralization was discovered in the nearshore facies of a regressive marine series. The host environment has been interpreted in terms of a sabkha. ‘Black ore’ U mineralization with coffinite was replaced by U ‘yellow ore’ composed of autunite, uranospathite and uranosilite (Braun et al. 1983). The ‘black ore’ U mineralization is probably Devonian in age. The oldest known strata-bound deposits in the Western Carpathians are subeconomic black-shale-hosted sulphide mineralizations. These include disseminated pyrite and a wide spectrum of elements such as V, Sb, Pb, Zn, Cu, As, Ag and Ni in rocks of the Tatricum (Little Carpathians) and the Gemericum (Spisˇ-Gemer Mountains) (SK) (Chovan et al. 1992). In the extra-Alpine Variscides, polymetallic U concentration was at a maximum during the Silurian and Early Devonian. The palaeogeography, organic matter and metamorphism of Lower Silurian black shales from the Barrandian Zone (Liten and Kopanina formations) were intensively studied (Suchy´ et al. 2002, 2004). During Silurian times, the Barrandian Zone occupied palaeolatitudes between 30 and 408S and was probably a narrow rift that developed over thinned continental crust (Havlıćˇek 1981). The Liten Formation was formed during a marine transgression following deposition of Upper Ordovician fluvioglacial deposits (Kosov Formation) (Brenchley & Sˇtorch 1989). The organic-matter-rich shaly formations are laterally correlative to deeper-marine shelf and slope environments partially influenced by active submarine volcanism (Kukal 1985). The sedimentary environment was apparently quiet, hemipelagic, and completely or at least partially anoxic, with only periodic influence of high-energy currents (Sˇtorch & Pasˇava 1989). Based on sedimentological evidence, the water depth during deposition

24

H. G. DILL ET AL.

of the Graptolite Shales did not exceed 150–200 m. Changing upwelling regimes and sedimentary environments across the Silurian–Devonian boundary are attributed to short-term sealevel fluctuations (Porebska & Sawlowicz 1997). The most promising mineralization in the Lower and Upper Graptolite Shales was deposited in the Saxothuringian Zone. Radiometric surveys carried out on black shales in the Thuringian-Franconian Massif yielded high readings due to the abnormally high U contents in the order of 60 ppm. The U contents of the black shales exceed significantly those of the over- and underlying Palaeozoic argillaceous rocks which average only 1–4 ppm U (Szurowski et al. 1991). High U contents together with elevated Cu (mean ¼ 353 ppm), Zn (3144 ppm), Ba (1583 ppm), V (3817 ppm) and Sb (100 ppm) qualify the Graptolite Shale as a low-grade/large-tonnage deposit like the Cambro-Silurian Alum Shale in Sweden, the Jurassic Posidonia Shale in south Germany or the Upper Proterozoic Fe–V–Ubearing shales in the Zˇelezne´ Hory Mountains (CZ) (Dill 1986a). There are strata-bound fault-hosted mineralizations with Fe-, Zn-, Cu-, Pb-sulphides and sooty pitchblende at the Gra¨fenthal Horst (D). The relatively high U contents render these Lower Palaeozoic black shales a ‘low-metal concentration’ or ‘protore’ for the U deposits which have been mined near Gera-Ronneburg (D) and Mo¨schwitz (D) (discussed in more detail in the section ‘Post-Variscan/early Alpine unconformity’). Carbonate-hosted manganiferous iron deposits. During the Ludlow, euxinic conditions were briefly interrupted and the dominant black shale facies was replaced by a carbonate facies (Seidel 2003). The Ockerkalk (D) is a calcareous unit deposited on swell zones. It formed during a sea-level fall, when the basin changed from the euxinic H2 S into the CO2 zone. As a consequence of this change, Fe was no longer accommodated in pyrite and marcasite but in siderite. The primary Fe concentration in the Ockerkalk is not of economic grade. However, where supergene alterations increased the Fe content, short-term mining operations were possible (see unconformity-related ‘Hunsru¨cktype’ deposits). Siderite in the Ockerkalk is considered to be a younger analogue of the siderite found in the (?Pre-) Cambrian Wunsiedel Marble. In the Western Carpathians black shales, stratigraphically equivalent to the Siluro-Devonian Graptolite Shales, are overlain by calcareous rocks. These carbonates form the parent material for large siderite (Nizˇna´ Slana´, Kobeliarovo (SK)), magnesite (Mnı´sˇek nad Hnilcom (SK)), ankerite (Hankova´-Volovec-Holec belt (SK)), and rhodonite- and rhodochrosite-bearing Mn deposits (Cˇucˇma, Betliar, Bystry´ potok (SK)), which formed at the beginning of the Late Palaeozoic as a result of metasomatism (Grecula et al. 1995) (see section on hypogene deposits related to the post-Variscan unconformity). Devonian to (Lower) Carboniferous The Devonian to Early Carboniferous evolution of the Variscan orogen was controlled by extensional and compressional events. Silurian(?)–Early Devonian ophiolites in the Central Sudetes probably represent a late stage of extension in the Saxothuringian Ocean (Franke & Zelazniewicz 2000). Contemporaneously, the Rheic Ocean located between Avalonia and the Amorican Terrane Assemblage was closed, whereas the Saxothuringian Ocean was subducted to the south beneath the Tepla´-Barrandian Zone during Early/Mid-Devonian time (Winchester et al. 2002). Thereafter, an extensional rifting phase occurred along the Rheic suture and formed the Devonian Rhenohercynian Basin (Oncken et al. 2000; McCann et al. 2008b). This basin was

dominated by thick clastic shelf sediments and rift-related volcanism. Further extension led to the opening of the Rhenohercynian Ocean. Sedimentary massive sulphide (SMS), VMS(Rammelsberg-type) and Lahn-Dill-type Fe–(Mn) deposits resulted from the rifting process. The volcanic-related mineralization began in the Middle Devonian with Fe deposits emplaced in the Rhenohercynian and Saxothuringian zones. The waning stages of this sedimentary exhalative (SEDEX) process lasted until the Lower Carboniferous when Mn-enriched analogues of the Lahn-Dill ores developed in the Rhenohercynian Zone. A chemical predisposition of the lithospheric crust in the Rhenohercynian Zone for base metals was responsible for the ubiquitous SMS and VMS deposits. The narrow Rhenohercynian Ocean was closed by SE-directed subduction during the Late Devonian–Early Carboniferous (Franke 2000). The lower Carboniferous successions in the extra-Alpine part of Europe include a shallow-marine limestone (Kohlenkalk) grading to the south into the deeper-marine synorogenic clastic Culm facies. Basement rocks in the Western Alps essentially form the direct continuation of the Moldanubian Zone in the French Massif Central. The situation in the Eastern Alps, Dinarides and the Carpathians is more complex. Penninic basement rocks, a part of the Austro-Alpine basement, and the Tatricum and Veporicum in the Western Carpathians record Silurian–Devonian metamorphism (Neubauer & von Raumer 1993; Neubauer et al. 1999). These units are considered to represent terranes, which were accreted along the active northern margin of the Rheic Ocean or an appendix of it (Frisch & Neubauer 1989). In contrast, the bulk of the basement rocks in the Eastern and Southern Alps and in the Dinarides belong to the Noric-Bosnian Zone, which split off Gondwana during (Silurian to) Early Devonian rifting and drifted northward until its Carboniferous collision with the European margin (von Raumer 1998). During the drift stage passive continental margins with thick carbonate platforms evolved. The main Variscan deformation, during collision of Gondwana and Laurussia, continued into Namurian–Westphalian times. This situation is similar to the geodynamic setting in the Gemeric unit (Western Carpathians), where rifting with extensive bimodal volcanism (Lower and Upper Ore-Bearing Horizons) commenced in the Late Silurian and extended into the Middle Devonian. Oceanic crust was formed in the central part of the rift during Late Devonian times. Here, Early Carboniferous-age sediments rest unconformably on folded and metamorphosed Lower Palaeozoic basement rocks. Sedimentation ceased due to the onset of movement of the Variscan nappes. These horizontal movements transported most of the Early Palaeozoic basin fill over the north continental plate. Subsequently, a basin formed in the area of the accretionary prism, filled with coarse siliciclastic material derived from Lower Palaeozoic rocks. This sedimentary complex (i.e. Rudnˇany conglomerates) became metamorphosed when subduction continued during the Late Carboniferous (Grecula & Radvanec 2004). Chromium–nickel–PGE and magnesite deposits. Ophiolites in the Central Sudetes are Silurian(?)–Early Devonian in age (Kroner et al. 2008). They contain Cr ore in the ultramafic massif of Ta˛padła (PL), where lenticular ore bodies are associated with dunites and diallag peridotites which underwent strong listvenitization. Chromium occurs in Al-bearing chromite attaining contents of c. 40% Cr2 O3 (Osika 1990). The Szklary Deposit (PL), also hosted by serpentinites, is well known for its high-quality Ni ore (Piwocki & Przenioslo 2004)

FOSSIL FUELS, ORE AND INDUSTRIAL MINERALS Magnesite deposits in extra-Alpine Europe are generally rare, with the exception of the Central Sudetic ophiolites (South Wroclaw), e.g. Sobo´tka (PL), Szklary (PL) and Braszowice (PL) (Osika 1990). In the large Konstanty Deposit at Braszowice, serpentinites and Variscan gabbroic rocks are cross-cut by magnesite veins. Iron–manganese deposits (Lahn Dill type/SEDEX). During the Middle and Late Devonian exhalative Fe ores of Lahn-Dill type formed in the Rhenohercynian and Marovo-Silesian zones. The strata-bound Fe deposits contain hematite, magnetite, leptochlorite and rarely siderite and pyrite (Skaćel 1966). The LahnDill Fe-deposits are generally bound to basaltic (diabase) and Na-trachytic (keratophyres) submarine lavas or their pyroclastic equivalents (Bottke 1963, 1965). Mining in the Lahn-Dill area (D) ended in 1973 with a total of 97 Mt of Fe ore exploited. The estimated reserves are 10–20 Mt. A cross-section through the hematite-bearing ore bed of the Langenbach mine (D) is shown in Figure 21.2b. The Middle to Late Devonian transition is marked by strong crustal extension accompanied by bimodal submarine volcanism. Spreading and the resultant submarine volcanism lasted in parts of the Rhenohercynian Basin until the Lower Carboniferous. In higher stratigraphic levels, hematite– magnetite ores became substituted by stratiform Mn ore mineralization which was mined at Laisa near Battenberg in Hessen (D) (Schaeffer 1998). It is a siliceous Mn ore made up mainly of rhodochrosite and braunite which were produced by volcanic solutions. West of the River Rhine, ferruginous sediments occur in several Lower and Middle Devonian horizons, bearing chamosite, hematite and goethite (Martin 1979; Simon 1979). The calcareous and oolithic iron ore was strongly deformed during the Variscan movements. Ore texture and the abundance of bioclastic limestones interbedded with the Fe ore seams suggest ore formation in a high-energy regime. These Fe ores are transitional from volcanosedimentary into true marine-sedimentary. Manganese quartzites at Eino¨d/Friesach (A) in Austro-Alpine units east of the Tauern Window are interpreted as Devonian-age oceanic sediments (Ertl et al. 2005) and supported minor wartime mining activities. Intensive bimodal volcanism of Devonian age also occurred in the Western Carpathians. Hematite–magnetite ore mineralization in Lower Palaeozoic rocks of the Gemericum is related in time and space with diabase–keratophyre volcanism resembling that of the Lahn-Dill Fe ore deposits in the extra-Alpine Variscides (Hnilec Formation, e.g. Trochanka, Hy´l’ov, Gondarska´, Sˇvedla´r (SK) (Grecula et al. 1995). Magnetite mineralization, in some places with associated pyrrhotite and chalcopyrite, occurs near Kokava nad Rimavicou (SK) in the Veporicum (Zoubek & Nemcˇok 1951). The primary oolitic Fe ore was metamorphosed at 550–5808C during the Variscan metamorphism and converted into a magnetite–grunerite–garnet schist (Korikovskij et al. 1989). In the Low Tatra Mountains (Tatricum) a similar pyrrhotite mineralization occurs near Hel’pa and magnetite occurrences are found NW of Bacućh (SK) (Grecula et al. 1996; Slavkay & Chovan 1996). Within the Dinarides SEDEX deposits with Fe, Mn and Ba occur in the Medvednica Mountains (Sˇinkovec et al. 1988), while stratiform occurrences of magnetite, chamosite and pyrite were encountered in the Palaeozoic rocks of the Kljucˇ area, NW Bosnia (Jurkovic´ 1959). Base-metal–iron sulphide–barite deposits (Rammelsberg type/SHMS type). A belt of syndiagenetic to syngenetic sul-

25

phide ores which formed during the Eifelian and Late Givetian extends from the Rhenohercynian to the Moravo-Silesian zones. Pyrite–barite ores with Zn, Pb and Cu sulphides were concentrated at Meggen (D) and Rammelsberg (D) (Fig. 21.5). The latter is the most prominent representative of this type of ore deposit, with 27 Mt of ore with 13.7% Zn, 5.9% Pb, 1.1% Cu, 100 ppm Ag and 22% BaSO4 (Dornsiepen 1976; Sperling & Walcher 1990; Maynard & Okita 1991; Large & Walcher 1999). Rammelsberg pyrite- and barite-bearing Zn–Pb–Cu deposit. The Rammelsberg mine located in the north Harz Mountains has a history of more than 1000 years (968 to 1988). In 1988 annual production was 55 000 t Pb+Zn, 3500 t Cu, 22 t Ag.

Fig. 21.5. Reconstruction of the Rammelsberg ore body (D) in its predeformational state (a) and after the Variscan folding shown in a crosssection through the Rammelsberg Deposit (b). Redrawn from Walther (1986).

26

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Intensive investigations of ore and country-rock have made it a classic example of a submarine hydrothermal deposit and its name is used to describe a class of strata-bound deposits. The mineral association consists of sphalerite, pyrite, barite, galena, chalcopyrite, pyrrhotite, covellite, arsenopyrite and tetrahedrite. Ore mineralization proper followed a pre-stage of silica concentration called ‘Kniest’. The wedge-shaped ore body of the ‘Kniest’ marks the vent systems (Fig. 21.5a). The main ore stage commenced with pyritic ore succeeded by sphalerite ore with little chalcopyrite. Shown in chronological order, a succession of barite–galena–sphalerite, barite–galena and barite evolved, terminating with the main ore stage. In the post-ore stage finegrained barite came up again and was mined from what is called the Grey Orebody, averaging 65 to 75% BaSO4. The entire orebearing Devonian series was intensively folded and faulted during the Variscan Orogeny and the ore beds converted into an isoclinal syncline where the ‘Kniest’ eventually came to rest in the hanging wall (Fig. 21.5b). At Meggen in the eastern part of the Rhenish Massif, 59.2 Mt ore grading 8% Zn, 1% Pb and 9.5 Mt barite were mined until 1992 (Werner & Walther 1995). A similar mineralization was mined for barite at the SW margin of the Rhenish Massif in the Korb Mine near Eisen/Hunsru¨ck (D) until 1988 and in the Rohberg Mine near Wiesbaden (D). Massive sediment-hosted pyrite–barite deposits near Lohrheim (Taunus) and Elbingerode (Harz Mountains) are genetically related to keratophyres of Devonian age. The Einheit deposit in the Harz Mountains (D), which was mined for pyrite until 1989, is a VMS deposit (Werner & Walther 1995). It produced 15 Mt of ore with 15 to 20% pyrite. The westernmost Rammelsberg-type strata-bound barite deposit of Devonian age was found when drillholes hit a Frasnian biostrome near Chaudfontaine (B) (Dejonghe 1998). The Rammelsberg-type deposits are considered to be a product of metalliferous basin-dewatering brines, conducing to SEDEX or SMS-type mineralization during the synrift phase of the Rhenohercynian Basin (Werner 1989; Maynard & Okita 1991). In the Moravo-Silesian Zone (eastern Bohemian Massif), Febearing base-metal deposits with subordinate amounts of Au formed in a geodynamic setting similar to that known from the Rhenohercynian Basin. The Devonian volcanosedimentary series (Vrbno Group), however, underwent regional metamorphism up to greenschist-facies conditions (Patocˇka & Vrba 1989; Kalenda & Vaneˇcˇek 1989). Several districts have been explored and exploited between 1959 and 1980 but all of them abandoned production by the beginning of 1994. Extensive mining was focused on deposits in the northern part of the Moravo-Silesian Zone (Zlate´ Hory (CZ), Hornı´ Me˘sto (CZ), Oskava (CZ), Hornı´ Benesˇov (CZ)). The total ore exploited from these deposits amounts to 100 Mt of mostly low-grade ore (Aichler et al. 1995). Due to Variscan metamorphism and deformation, the stratabound ore is completely recrystallized and intersected by numerous Au-bearing quartz and sulphide veins. The S isotope ratios obtained from barites closely resemble those from Meggen and Rammelsberg, whereas the sulphide sulphur is isotopically much lighter (Hladı´kova´ et al. 1992). High radiogenic Pb contents of the galena-enriched ore show the significant contribution of upper crustal rocks to the metal-bearing hydrothermal or exhalative solutions creating the strata-bound mineralization in the Moravo-Silesian Zone (Vane˘cˇek et al. 1985). In the Massif Central (F), Late Devonian-age base-metal deposits have been exploited for Cu and Zn from pyritic lenses associated with quartz–keratophyre rocks in the old Sain-Bel mine (F) and at Chessy (F), where chalcopyrite and sphalerite are associated with barite averaging 2.5 wt% Cu, 10 wt% Zn and

15 wt% Ba (Bril et al. 1994). The latter mineralization occurs in two effusive acid volcanic units (mainly submarine lava flows) characterized by dacitic to rhyolitic composition (Lacomme et al. 1987; Milesi & Lescuyer 1993). The ore bodies comprise a central zone with alternating beds of pyrite, sphalerite and thin volcanic flows surrounded by a barite rim. The main ore body is rooted in quartz–pyrite–white mica stockworks. Similar stockworks occur at several volcanic levels, demonstrating the longevity of hydrothermal activity in the Chessy area (Lacomme et al. 1987). In the Eastern Alps, ore mineralization of Cu, Fe, Pb and Zn occurs within Lower and Upper Austro-Alpine nappes. Mineralization in the Lower Austro-Alpine nappe was pervasively deformed and subjected to several phases of regional metamorphism, e.g. Pitten (A). This is usually taken as proof of preAlpine syngenetic ore formation that took place under euxinic conditions in an active continental margin setting (Ebner et al. 2000). Ore formation within the Upper Austro-Alpine Nappe (Noric Composite Terrane) was controlled by extensional tectonics, alkaline basaltic intraplate volcanism and euxinic environments (Weber 1990). Strata-bound mineralization is predominantly of SEDEX and VMS type, including Fe–Cu(Pb– Zn) (e.g. Meiselding (A)) and Pb–Zn–Ag(Ba) associations (e.g. Schwaz, Graz Palaeozoic Complex (A)). Generally the Pb isotopes of these ores suggest a crustal origin for the Pb. Of particular importance is the stratiform Pb–Zn mineralization of volcanosedimentary origin, which is widespread within Silurian and Devonian (meta)sediments of the Graz Palaeozoic Complex (e.g. Arzberg (A)) (Weber 1990). These deposits resulted from hydrothermal activity at the seafloor which provoked a warming of the seawater in semiclosed basins. The warming of the seawater together with poor water exchange with the open sea were responsible for the euxinic conditions in these basins. In the Smolnı´k Formation in the Gemericum (Western Carpathians), the origin of base-metal deposits, concentrated in an upper ore bed, and hematite and magnetite deposits in a lower ore bed are both linked to basalts and keratophyres with the type localities in Jalovicˇ´ı vrch and Hutna´ dolina deposits (SK), respectively (Grecula 1982; Grecula et al. 1995). Sulphur isotopes of sulphides (+2 to +15‰) (Zˇa´k et al. 1991; Radvanec et al. 1993) suggest a Lower Palaeozoic source of marine sulphate and inorganic or biogenic reduction in a closed system. In the Smolnı´k Deposit massive pyritic ores in the central part of the ore horizon grade outwards into disseminated pyritic ores. During the most recent mining period, the element contents of the ore decreased to 0.2–0.6% Cu, while in the past it was much higher with 2–4% Cu, up to 0.33% Pb, up to 0.37% Zn and up to 8 g/t Ag. A total of c. 19 Mt of ore was exploited in the period 1326–1990 with the remaining resources of ore totalling about 6.2 Mt (Poprenˇa´k & Ilavsky´, in Bartalsky´ 1993). Tungsten and magnesite deposits. Ore formation within the Noric Composite Terrane (Eastern Alps) includes W mineralization and small magnesite bodies (e.g. Mallnock (A)) linked to black shales (Neinavaie et al. 1989). Copper–molybdenum–tungsten deposits (porphyry type). The majority of porphyry Cu deposits are associated with Mesozoic and Cenozoic orogenic belts, island arcs and active continental margins (e.g. Mitchell 1996; Herrington 2000). A peculiar type of porphyry Cu deposits has been recorded from Central Europe by Haranczyk (1980, 1983). The mineralization does not show all of the features known from modern ‘disseminated porphyry Cu deposits’ and is also erratically distributed

FOSSIL FUELS, ORE AND INDUSTRIAL MINERALS within the Variscan metallogenetic cycle in Central Europe. The polyorogenic Krako´w and Moravian mobile belts, both deformed during the Caledonian and Variscan orogenies, include the western margin of the Małopolska Zone and parts of the Moravo-Silesian Zone. These are the locus of Early Carboniferous-age igneous activity with associated porphyry Cu mineralization. Late Palaeozoic Cu–Mo–W porphyry deposits formed at Mrzyglod– Zawiercie (PL), Pilica (PL), Dolina Bedkowska (PL) and Miedzianka–Stara Go´ra (PL) (Haranczyk 1980, 1983; Osika 1986; Chaffee et al. 1994). Upper Carboniferous Early Carboniferous thrust loading resulted in the formation of the large Variscan foreland basin, which extended to the north of the Variscan Front between Ireland and Poland. Overlying marine sediments, this asymmetric basin was filled mainly with continental deposits during the Late Carboniferous. At the same time, intramontane basins, orientated subparallel to the Variscan core zone, formed within the Variscan Orogen. However, deposition in these latter basins continued into the Permian, and so they will be discussed in the Alpine section. Coal is the most important resource in Upper Carboniferous strata; however, ironstone also formed in the Variscan Foreland Basin. Coal deposits in the Variscan Foreland. During Late Carboniferous times the Variscan Foreland Basin was filled with coalbearing molasse sediments, several kilometres thick. Overlying the Lower Carboniferous carbonate platform and associated flysch sediments, the coal measures display a gradual shift from marine-influenced to continental settings. The internal architecture of these deposits is characterized by repeated successions (cyclothems) of siliciclastics, coal and carbonate controlled by sea-level variations (Izart et al. 1998). Coal formation during Late Palaeozoic times was promoted by a tropical climate and favourable palaeogeographic and tectonic conditions (McCann et al. 2008b). The stratigraphic range of the Palaeozoic coal measures is indicated in Figure 21.6. Several major coal districts are located within the Variscan Foreland Basin and these show a number of common features including a very high number of relatively thin, but often extensive seams. Coal rank ranges widely from high volatile bituminous to anthracite. Coalification mainly occurred during deep burial and is mainly pre-deformational. Therefore, rank isolines generally dip parallel to bedding planes (e.g. Juch 1991; No¨th et al. 2001). The seams are strongly deformed, with the intensity of deformation decreasing with distance from the Variscan Front (e.g. Oncken et al. 2000). Marine bands and volcanic ash layers are frequent and form important lithostratigraphic marker horizons. Coal mining commenced as early as the twelfth century in southern Belgium (Dinant Syncline). However, large-scale industrial coal mining only began in the nineteenth century. In total more than 20 Gt of hard coal have been produced in the Belgian, German, Czech and Polish sectors of the basin. Today mines are active in this area only in the Ruhr District (coal production in 2005 was 20 Mt) and in the Upper Silesian Basin (c. 110 Mt). About 4.5 Mt are produced annually by a coal mine in the Polish part of the Lublin Basin. Wallonian and Campine basins. Extensive coal mining activities took place in the Nord-Pas-de-Calais Basin (F) and in the Namur Syncline (B), located on the southern flank of the Brabant Massif (Fig. 21.7a). Smaller depleted deposits also occur in the Dinant Syncline. The Namur and Dinant synclines (Wallonian

27

Basin) extend eastwards into the Aachen coalfields, which are also connected with the South Limburg (NL) and Campine basins (B) to the north of the Brabant Massif. In the Campine Basin, the Upper Carboniferous coal measures are disconformably overlain by Permo-Mesozoic and Cenozoic sediments and were, thus, only detected in 1901. The Westphalian succession, with a maximum preserved thickness of 3.5 km, reflects a change from lower delta plain to braid plain settings. Westphalian A lower delta plain coal is generally thin (,1 m) and often split. The Westphalian B hosts many seams up to 3 m thick and was the main coal-producing unit. The Westphalian C contains rather thick seams (up to 5 m), partly formed in raised mires. Only a few mineable seams are associated with the gravelly braid plain (Westphalian D; Dreesen et al. 1995; Langenaeler 2000). Major differences exist in the tectonic style of the basins. The Wallonian Basin, located near the Variscan Front, was strongly affected by folding and thrusting. In contrast, Variscan deformation of the gently north-dipping Campine Basin was minor. Its structural style is dominated by NW–SE-striking normal faults causing a rapid deepening of the coal measures towards the NE. A western and an eastern mining district are separated by the north–south Donderslag Fault Zone. The thickness of sediments and coalification are significantly higher in the eastern part of the Campine Basin (Dreesen et al. 1995; Van Keer et al. 1998). Average seam thickness in the Wallonian and Campine basins is 0.6 m and 1.1 m, respectively. Ash and sulphur contents are low. Coal rank ranges from high volatile bituminous to anthracite. Coalification occurred mainly during deep Westphalian burial, but Jurassic subsidence and slightly elevated heat flows may have caused a second coalification event in the eastern Campine Basin (Langenaeker 2000; Van Keer et al. 1998). Unfavourable geological factors led to the closure of the last mine in the Wallonian Basin in 1984. Coal mining in the Campine and Aachen areas continued until 1992 and 1997, respectively. Huge mineable coal reserves remained in the Campine Basin (van Tongeren et al. 2002). Van Bergen et al. (2003) highlight the coal-bed methane potential. Ruhr Basin (including Ibbenbu¨ren). Folded and thrusted Upper Carboniferous coal measures crop out along the River Ruhr (Fig. 21.7b). Here, coal mining began in the fourteenth century. Current mining activities are concentrated northwards below the Mu¨nsterland Basin down to a depth of 1500 m. The Ruhr Basin (RB) covers an area of about 12 000 km2 . The erosional surface of the Carboniferous dips northwards beneath up to 2 km of Upper Cretaceous strata of the Mu¨nsterland Basin (Fig. 21.7c). The north basin margin is formed by a prominent strike-slip fault (Osning Fault) separating the basin from the Lower Saxony uplift zone. Within the inversion zone, three NW–SE trending blocks, with coal-bearing sediments, are exposed (Fig. 21.7; Ibbenbu¨ren District). The coal measures (Namurian C–Westphalian D) in the RB thin northwards from about 5 km to less than 3 km (Drozdzewski 1993). A lower delta plain environment prevailed from Namurian C to Westphalian B and was replaced by an upper delta plain during the Late Westphalian C. The marine influence decreased during the Westphalian B/C and a general regressive trend ended in the deposition of red-beds and the formation of palaeosols in the Westphalian D, mainly in the north of the RB (Drozdzewski 1993; Strehlau & David 1989). More than 100 coal seams of variable thickness are present in the RB. The thickest seams are 2.8 m thick. The coal seam distribution shows two trends (Drozdzewski 1993): (1) from the Namurian C to the Westphalian the area with maximum coal

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Fig. 21.6. Stratigraphic position of late Palaeozoic coal-bearing sediments. Series with economic seams are indicated by grey shading (after Zdanowski & Zakowa 1995; Izart et al. 1998; Oplustil & Pesˇek 1998).

content shifted towards the NW; (2) within each formation the coal content decreases in the same direction. The maximum net coal thickness occurs in the lower Westphalian B (Gaschnitz 2001). Extensive seams with low-ash, low-sulphur coal dominate in the upper Westphalian A to lower Westphalian C and were interpreted as former raised mires or as open mires with herbaceous vegetation (‘densosporinite facies’; see review Dehmer 2004). Upper Westphalian C coal formed in forest swamps (‘vitrinite-fusinite facies’) and is less clean. On average, the coal consists of about 70% vitrinite, 20% inertinite and 10% liptinite (Scheidt & Littke 1989).

The RB was affected by folding and thrusting during the Stephanian. The intensity of folding decreases towards the NW (Fig. 21.7). NW–SE trending faults affected the Carboniferous strata slightly after folding and thrusting. These faults are generally extensional in nature, with some evidence of lateral movement. The Blumenthal Fault (Fig. 21.7b) subdivides the RB into a western and an eastern part. The coal measures in the west are mostly flat-lying and covered by Permo-Triassic sediments. In contrast, the Carboniferous in the east is intensely folded and directly overlain by Cretaceous rocks. The NW–SE extensional structures were reactivated during Mesozoic and Cenozoic times. During Late Cretaceous basin inversion, the ‘Lower Saxony


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Fig. 21.7. (a) Structural subsurface map of the Variscan Front in Central Europe (modified after Drozdzewski 1993). (b) Geological map of the Ruhr Basin and northern areas (without Mesozoic cover). (c) Geological cross-section (modified after Walter 1992).

uplift zone’ overthrust the northern edge of the Mu¨nsterland Basin (Fig. 21.7). Uplift was perhaps accompanied by deep mafic intrusions. A post-Albian to pre-Late Campanian age for this magmatic event has been postulated based on a coalification anomaly. However, numeric basin models suggest that high

thermal maturity is a result of deep Cretaceous burial (Petmecky et al. 1999; Senglaub et al., 2006). Today, low-volatile bituminous coal and anthracite are exploited in the Ibbenbu¨ren district. Coal rank in the RB (sensu stricto) ranges from high-volatile bituminous to semi-anthracite. Carboniferous rocks, up to 2.8 km

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H. G. DILL ET AL.

thick, were eroded during post-Stephanian uplift in the Mu¨nster area, whereas up to 6 km were eroded at the southern basin rim (Bu¨ker et al. 1995). Renewed subsidence commenced during the Late Permian and was followed by Late Jurassic to Early Cretaceous uplift. Mesozoic subsidence did not influence coal rank in the main part of the RB (Littke et al. 1994, 2000). Both coals and dispersed organic matter are sources for coalbed methane (CBM). The two parts of the RB have different CBM contents. The western area is characterized by a gas-free section below the post-Carboniferous cover. In contrast, gas contents increase directly below the cover in the east. Gaschnitz (2001) has shown that gas distribution and gas composition are controlled by phases of exhumation and reburial causing complex adsorption–desorption cycles. Maximum CBM contents are related to anticlines or horst structures and reflect lateral gas migration and accumulations due to vertical differences in permeability (Kunz 1999). Today, CBM is produced in areas with active and abandoned coalfields in the southern RB (Thielemann 2001). The Upper Silesian Basin (USB) straddles the border between Poland and the Czech Republic and covers an area of about 7250 km2 (Dopita & Kumpera 1993; Jura et al. 2000) (Fig. 21.8). The USB formed within the eastern foreland of the Moravo-Silesian foldbelt. The thickness of the Upper Carboniferous molasse deposits increases dramatically towards the west (8.5 km). As in other Variscan foreland basins, the coal measures include a lower paralic (Namurian A) and an upper continental series (Namurian B to Westphalian D). However, in the USB continental conditions were established earlier than in other districts. The overburden is formed by thin (,200 m) Permian to Jurassic sediments in the northern part and by Miocene rocks, including salt deposits, in the south (Fig. 21.8). In the basin

centre, the Carboniferous is overlain by Quaternary sediments. The Variscan Orogeny led to the formation of two distinct tectonic zones: folds and thrusts predominate in the western part, whereas the eastern part is characterized by a flat syncline with roughly west–east trending faults. The southern part of the basin became overthrust by Carpathian nappes during Neogene times. The Paralic Series (Ostrava Fm. in CZ; Namurian A) was deposited in coastal plains and vast deltaic systems. It contains numerous horizons with marine and brackish fauna and 114 economic coal seams with an average thickness of only 0.73 m. The percentage of coal within the Paralic Series is 2.6%. The continental sediments (Karvina´ Fm. in CZ; Namurian B– Westphalian D) were deposited following a break in sedimentation. In Poland, they are subdivided into three series. The Upper Silesian Sandstone Series (Namurian B–C) is characterized by a predominance of coarse-grained sediments of braided river systems and has 23 thick seams. Seam thicknesses range from 4 to 8 m and may reach 24 m. The cumulative percentage of coal is 7.3%. Pelitic rocks deposited on the alluvial plain of meandering river systems predominate in the Siltstone Series (Westphalian A–B) and contain 71 economic, but relatively thin, seams (0.4–1.3 m). Nevertheless, the percentage of coal in the Siltstone Series is 5.6%. The Cracow Sandstone Series (Westphalian B–D) formed on alluvial plains of a braided river system and has 26 economic seams, the thicker seams reaching 7 m. The share of coal is 2.9%. Barren Stephanian sediments complete the Carboniferous profile. Coal rank (sub-bituminous C–anthracite) exhibits complex coalification patterns, because coalification during deep Carboniferous burial was overprinted during Mesozoic and Cenozoic times. Post-orogenic heating is perhaps related to deep igneous activity (e.g. Kotas & Hadro 2001). Ash yields are highly variable, while average sulphur content is 1.1%af . Continental

Fig. 21.8. Geological map of the Upper Silesian Basin (simplified after Jureczka & Krieger 2000). Methane contents in two drillholes are shown after Kotarba (2001).

FOSSIL FUELS, ORE AND INDUSTRIAL MINERALS coals are significantly thicker and contain more inertinite than paralic coals (Dopita & Kumpera 1993). Coal is used as steam coal and for coke production. In terms of CBM potential a southern area with thick impermeable Miocene overburden, and a northern area without sealing rocks can be distinguished (Jureczka 1995; Kotarba 2001). In the southern area two zones of high methane contents occur: an up to 300 m thick ‘methane cap’ beneath the top of the Carboniferous, and a primary methane zone at a depth of 1000 to 1500 m. In the northern area, only the primary zone is preserved, below a 500 to 1000 m thick degassing zone (Fig. 21.8). The USB has the potential to become one of the world’s largest CBM producers. In addition, CO2 sequestration in coal seams is currently tested in the USB (e.g. Gale 2004). Underground mine water in the USB is often highly mineralized, a consequence of the presence of a salt deposit in the Miocene overburden. A major part of the saline brines is discharged into the Vistula and Odra rivers causing serious ecological problems. Only the NW edge of the Lublin Basin (Poland, Ukraine) is situated within the borders of the study area. The basin formed on the slope of the East European Craton. Its Upper Carboniferous succession, up to 3.5 km thick, comprises marine–paralic (Upper Viseán to Namurian A), paralic (Namurian B to Westphalian A) and continental (Westphalian B–D) deposits with a large number of coal seams (Porzycki & Zdanowski 1995). Late Variscan deformation resulted in uplift, erosion and the formation of a series of NW–SE striking folds. The coal measures are discordantly overlain by Mesozoic deposits. The most important seams present are connected with the continental Lublin Formation. The average thickness of these seams is 1.4 to 3.5 m. The Lublin coalfield was discovered only relatively recently. Production of high- to medium-volatile bituminous coal (22 MJ/kg, 10% ash, 1.0–1.5% S) in the Polish part of the basin commenced in 1984. Production is from two seams at 800 to 1000 m depth (Philpott 2002). The coal is used mainly in power stations. Proven economic reserves are enormous. Graphite deposits in the Alpine belt. Graphite occurs in Upper Carboniferous molasse sediments and was produced in several mines in the Greywacke Zone of the Eastern Alps (e.g. Kaisersberg (A), Trieben (A)). Within the Western Alps, graphitebearing rocks with a supposed Carboniferous age occur in the Dora-Maira Massif (Pinerolo Valley; Ridoni 1938). Graphite mineralization at Icla (I) and Brutta-Comba (I) occurs in a single horizon, variable in thickness from a few centimetres up to a few metres, within metamorphic rocks comprising paragneisses, garnet-bearing mica schists and minor quartzites. The average C content is about 60–80%. Ironstone deposits in the Variscan Foreland and in intramontane basins (claybands and blackbands). Thin seams of Fe ores called claybands and blackbands formed during Late Carboniferous times in the Variscan Foreland. They are interbedded with coal seams and form part of the paralic facies in the coal measures (Walther & Dill 1995). Several seams of sideritebearing ironstones were mined in the Ruhr Basin (D). Beds enriched in siderite are also found alternating with seams in the intramontane Saar-Nahe Basin where they were mined as Fe ores (even perhaps in pre-Roman times) during 1852–1912 and 1934–1942 with a total of 10 Mt of Fe ore extracted. The origin of these clayband and blackband Fe ores is related to the special

31

palaeogeographic and climatic conditions which also favoured coal accumulation.

Thrust-bound and fold-related metamorphogenic deposits Activation of the continental margin of the Mid-German Crystalline High resulted in the initiation of south-directed subduction in the early Late Devonian. The Rhenohercynian and Saxothuringian crust was consumed by this subduction. During the Early Carboniferous, the Rhenohercynian Basin closed and subsequent Variscan collisional tectonics led to the accretion of shelf sediments and igneous activity along deep-seated suture zones (Franke & Oncken 1990; see McCann et al. 2008b for more details on the tectonic history). As a result of crustal deformation, thrust-bound and foldrelated metamorphogenic deposits were formed. These are markedly different from epigenetic vein-type deposits of postVariscan age (Dill 1985b). The Variscan ore in the Rhenohercynian Zone, containing Sb, Pb, Zn, Cu sulphides, Au and siderite, shows pervasive textural distortion and strong mylonitization. Base metals, Sb, Au and siderite are related to shear zones and cleaved psammo-pelitic series, that developed along the fold axes of the Variscan anticlines. Silver-bearing base-metal vein-type deposits Variscan-age base metal vein mineralization contrasts strikingly with Alpine-age vein mineralization. Silver-enriched tetrahedrite and Fe-enriched sphalerite are uncommon in the post-Variscan vein mineralization (Schaeffer 1984; Krahn 1988). The Pbisotopic signature of the Variscan vein mineralization also differs from the post-Variscan (Saxonian) mineralization in that it is distinctly more radiogenic (Krahn & Baumann 1996). On the other hand, there is a striking similarity in the Pb-isotope signatures between the fold-related metamorphogenic vein-type deposits and strata-bound Devonian base-metal mineralization, suggesting that the source of metals for both types of deposits is within the Devonian synrift volcanosedimentary rock succession. The Pb–Zn veins in the Rhenish Massif at Bensberg (D), Ramsbeck (D), the so-called ‘schistosity or cleavage-parallel veins’ near Holzappel (D), Werlau (D), Tellig (D) and Altlay (D), may be attributed to Variscan thrust-bound epigenetic mineralization (Podufal 1983; Fenchel et al. 1985; Werner & Walther 1995; Wagner & Boyce 2001). The veins in the Bensberg (D) Pb–Zn mining district have been worked since 1934 by Altenberg AG. Hesemann (1978) has estimated the Pb + Zn quantity in the Bensberg mining disctrict at 3 Mt. Mining was forced down in 1978 by citizens’ actions which stopped exploitation of a newly discovered ore body near Bensberg (D). From 1840 to 1974, the production in the largest deposit at Ramsbeck totalled about 16 Mt ore, averaging 4.4% Zn and 2.1% Pb. The syntectonic hydrothermal Pb–Zn veins of the Ramsbeck deposit have been extensively overprinted by latestage fluids responsible for fissure vein mineralization. This has caused remobilization of vein components, notably of sphalerite and galena, as well as the formation of various Sb sulphosalt minerals, including boulangerite, semseyite, tetrahedrite and bournonite (Wagner & Boyce 2001; see also Siegerland-type vein deposits discussed below). Udubasa (1996) has compared synand epigenetic Pb–Zn deposits of the Ramsbeck mining district with Pb–Zn deposits in the Eastern Carpathians. Silver, Pb, Zn and Cu accumulations in the Prˇ´ıbram ore district (CZ) (Bohemian Massif) were also attributed to the thrust-bound and fold-related metamorphogenic ore mineralization, although there are remarkable structural differences between the metamor-

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phogenic veins in the Rhenohercynian and Tepla´-Barrandian zones. In the Rhenohercynian Zone the structural deformation and metamorphic alteration of the Lower Palaeozoic rocks was less intense and occurred at shallower crustal levels than in the Bohemian Massif. Several base-metal veins were emplaced around the Central Bohemian Pluton where underground mines reached an operational depth of more than 1500 m. The ore veins are feather structures accompanied by diabase dykes of similar shape (Pouba & Ilavsky 1986). Important Ag carriers besides galena are pyrargyrite, stephanite and diaphtorite. Copper-bearing iron oxide and selenium vein-type deposits Hydrothermal veins of probable Variscan age were the target of mining operation for Fe during the nineteenth and early twentieth centuries in the Harz Mountains near Zorge and St. Andreasberg (D) (Neumann-Redlin et al. 1977). The major ore mineral is hematite associated with chalcopyrite. In the same mining district selenides were discovered in veins near Tilkerode (D) and Zorge (D) (Tischendorf 1960; Ramdohr 1975). Investigations have revealed that this Se vein mineralization is of no economic, but of utmost mineralogical, importance for its rare minerals. The selenide mineralization occurs as aggregates in a carbonate matrix, and is composed of clausthalite, tiemannite, chrisstanleyite, stibiopalladinite and Au. Only recently a new Pd–Hg selenide was discovered from the Eskeborn Adit at Tilkerode: Tischendorfite (Pd8 Hg3 Se9 ) (Stanley et al. 2002). The origin of this mineralization is not yet fully understood. Palladium and Au associated with selenide minerals in these veins may have either derived from the country-rocks or originated by downward movement of oxidizing solutions circulating in the Permian rocks and reacting with more reduced solutions below the unconformity. If the latter model proves to be correct, this unique Se vein mineralization will have to be categorized as unconformityrelated. At Mont Chemin (CH) magnetite-bearing lenses occur in tightly folded sericite gneisses and mica schists that form part of the metamorphic envelope around the Variscan Mont Blanc Massif (De Quervain & Zitzmann 1977; Beck & Serneels 2000). In addition to martitized magnetite, some pyrite and Co arsenides are present in the ore bodies. Subsequent metamorphism has altered the primary mineral assemblage and overprinted the texture to such an extent that the origin of this Fe deposit is still a matter of conjecture (Hugi et al. 1948). The attribution of the Mont Chemin Fe deposit (CH) in this text to the thrust-bound (transitional into granite-related (?)) deposits is mainly for textural reasons reflecting the latest stages of remobilization of the Fe ore and its spatial relation to the Variscan Mont Blanc Massif. A plausible alternative would be an attribution of the Fe deposit to the Early Alpine unconformity-related deposits (compare fluorite veins in the country-rocks of the Mont Blanc Massif discussed below). Siderite–copper–lead–zinc vein-type deposits (Siegerland type) The Siegerland Fe district (D), located in the Rhenish Massif, was one of the major mining districts in Germany. After 2000 years of operation and a production of 175 Mt of Fe ore, the last mines were shut down in 1965. Hein (1993) suggested that the Siegerland siderite veins, which extend down to a depth of 1000 m, formed from low-salinity CO2 -undersaturated fluids at temperatures between 180 and 3208C following the peak of metamorphism and prior to the post-kinematic magmatism. The textural and paragenetic relationships of sulphide and sulpho-salt minerals within the Fe–Cu–Pb–Sb–Bi hydrothermal veins show evidence of an earlier primary sulphide mineralization with

pyrite, chalcopyrite, galena and sphalerite as the main components, subsequently overprinted by Sb-, Bi- and Cu-rich fluids. This superposition resulted in the formation of new quartz– boulangerite–stibnite veins (Wagner & Cook 1997). Detailed investigation of polysulphide mineralization, alteration and fluid characteristics of a high-strain zone in the Lower Palaeozoic rocks of the Brabant Massif (B) by Piessens et al. (2000) may offer a possible clue to unravel the history of thrustbound mineralization in the NW part of the Variscides. Ore mineralization occurred synkinematically and was closely associated with the shearzone. Low saline H2 O–CO2 –(–CH4 )–NaCl fluids with temperatures .2608C were involved in the hydrothermal circulation, which caused alteration of the host rock. Isotope data and the general setting indicate a metamorphicdriven system, that may be attributed to the main Early to early Middle Devonian deformation event. Metamorphogenic fold-related deposits are also widespread in the Carpathians where siderite–sulphide veins formed in lowgrade rocks and quartz-Sb veins in higher-grade metamorphic rocks (Fig. 21.9). The siderite–sulphide veins extend from several hundreds of metres up to 15 km. A total of 80 Mt of siderite have been mined and 50 Mt of reserves have been calculated (Fenchel et al. 1985). Quartz-Sb veins are smaller in length but deserve mentioning due to their Au contents of up to 2 g/t (Chovan et al. 1995; Grecula et al. 1995; Dill 1998). The mineral successions in the most important siderite– sulphide ore deposits at Rudnˇany (SK), Slovinky (SK) and Rozˇnˇava (SK) show marked differences, especially as far as siderite and barite distribution are concerned (Bernard 1961; Ha´ber 1980; Rojkovicˇ 1977; Chovan et al. 1994; Sasva´ri & Mat’o 1996). Barite was mainly concentrated in the Rudnˇany deposit where barite veins give way to stratiform barite lenses and layers (Grecula et al. 1995; Zˇa´k et al. 2005). Chalcopyrite, tetrahedrite, galena and sphalerite usually precipitated together with barite but do not form individual veins. Mercury is widespread in all these mineral associations. There is common consensus that the cinnabar which is present is indicative of the youngest (?Alpine) stage of siderite–sulphide mineralization (Radvanec et al. 2004a). The origin of siderite–sulphide veins is the subject of considerable controversy. Some authors suggest that they are related to Late Carboniferous or Permian-age basic intrusions (Ilavsky´ et al. 1977), while others suggest that they are related to Alpine granite magmatism (Rozlozˇnı´k 1989), or to Alpine metamorphism (Schneiderho¨hn 1962). The Rb–Sr isotopic ages of granites in the Gemericum indicate a Permian intrusion age (290 40 to 220 32 Ma; Kovaćh et al. 1986) and form the basis for the metamorphic–hydrothermal model for the siderite–sulphide and pure sulphide veins in the Gemericum (Grecula 1982; Radvanec et al. 2004a). The sulphur source has been constrained by isotope analyses. Positive 34 S data between +3 and +10‰ for the sulphides are indicative of sulphur remobilized from stratiform sulphide accumulations in Lower Palaeozoic Gemericum sequences. Variable 34 S values for barite (+5 to +18‰) are interpreted as resulting from oxidation of sulphur accommodated in the lattice of sulphides. The 13 C data for siderite (–8 and –3.5‰) and 18 O data (+14.5 and +21‰) yielded formation temperatures between 150 and 2008C (Zˇa´k et al. 1991). The CO2 of fluids was derived from the mixing of organic-matter-derived and carbonate-derived CO2. The 87 Sr/86 Sr isotope ratios (0.71042 to 0.71541) of barite suggest a crustal source related to the Variscan magmatometamorphic M1 event (Radvanec et al. 1990). New 87 Sr/86 Sr


33

Fig. 21.9 Transverse geological profile through the Rudnˇany deposit (Hudaćˇek & Fabian, in Grecula et al. 1996).

data obtained from analyses of strontianite and celestite (sampling was carried out in veinlets cutting the siderite–sulphide veins) from the same mineral district are significantly higher than the 87 Sr/86 Sr range obtained by Radvanec et al. (1990) for the main-stage barite. The results suggest that a phase of hydrothermal activity contemporaneous with the Alpine metamorphism M2 was superimposed on the older Variscan mineralization (Radvanec et al. 2004a). Petrological data suggest that metamorphic fluids released during the Variscan low-pressure/medium-temperature metamorphism contributed significantly both to the vein siderite– sulphide mineralization and to the replacement siderite deposits.

4

Gold–antimony–arsenic vein-type deposits (mesothermal gold– antimony vein type) In the Rhenohercynian Zone, thrust-bound Sb mineralization is found in some deposits scattered across the Rhenish Massif, e.g. Ahrbru¨ck (D), Wolfsberg (D), Nuttlar (D), Arnsberg (D), Raubach (D) and Goesdorf (L) (Wagner & Boyce 2003). It is a mineral assemblage of low diversity dominated by stibnite and quartz with subordinate Pb sulphosalts such as jamesonite, zickenite and chalcostibite but without economic Au contents. Minor stibnite mineralization has also been recorded from the Siegerland-type siderite veins (see previous section). In the Saxothuringian Zone thrust-bound Sb mineralization is very common in vein-type deposits, mainly along the Berga and Fichtelgebirge anticlines (Fig. 21.2c). This vein mineralization contains not only stibnite, arsenopyrite and Sb sulphosalts but also native Au (e.g. Brandholz (D)) and cinnabar (e.g. Hornı´ Luby (CZ)) (Dill 1985; Kvet 1994). Antimony was mined near Schleiz (D) and Greiz (D) until the 1950s and at Wolfersgru¨n

(D) in the 1920s. At Brandholz (D) and Neualbenreuth (D) the old mining sites were revisited during the 1970s, but proved to be no longer feasible for Au mining. Following an Early Palaeozoic protore stage (see section on Ordovician–Silurian strata-bound deposits above), Au, Sb and Hg were redeposited along thrust zones parallel to the Schwarzburg, Berga and Fichtelgebirge-Erzgebirge anticlines (Dill 1993). Polymetallic Au-stibnite mineralization occurs in a proximal position relative to the anticlines cored by the Late Variscan granites, whereas the monotonous stibnite veins, lacking Au of economic grade, are located in a more distal position relative to these ‘high-heat zones’. The Złoty Stok (PL) As–Au deposit located in the Lugian Zone was the largest producer of primary Au in the Western Sudetes until its closure in 1961. Its origin is still under discussion (Mochnacka et al. 1995) with the most recent interpretation suggesting a hydrothermal/metasomatic origin. Gold is concentrated in loellingite with an average ore grade of between 3 and 5 ppm Au. In the Moravo-Silesian Zone low-sulphide quartz veins and quartz mobilizates also have anomalously high Au contents. The ratio of free Au to Au accommodated in the sulphides is a function of metamorphic remobilization. Sulphide Au-quartz vein mineralization of the Ande˘lska´ Hora District (CZ) is encountered along cleavage planes, foliation and fold-related joints in slates, tuffs and dolerites of the Devonian-age Vrbno Group. The thrusted and metamorphosed slates were favourable ˘ ursites for ascending metamorphogenic/hydrothermal fluids (D isˇova´ 1990). Much effort has been invested in Au exploration in the central part of the Bohemian Massif (Central Bohemian Shear Zone; e.g.

34

H. G. DILL ET AL.

Koubova´ et al. 2001). Accumulations of Sb and Au were found ˇ elina (CZ) and Roudny (CZ) at Jı´love´ (CZ), Mokrsko (CZ), C (Mra´zek 1986; Mora´vek & Pouba 1990; Mora´vek 1996a, b; Stein et al. 1997; Zacharia´sˇ et al. 2004). Metamorphic quartz lenses occur in the Kasˇperske´ Hory Au district (CZ) (Pertoldova´ et al. ˘ urisˇova et al. 1995; Pertold & Puncocha´r 1995). The 1993; D low-sulphide Au mineralization is hosted by paragneiss and migmatite with intercalated quartzite, calc-silicate rocks, felsic volcanic rocks, amphibolite and marble. The mineralization is bound to east–west trending zones containing native Au of high fineness (.910), Au–Bi–Te minerals, and scheelite. The Mokrsko deposit (CZ) is one of the largest Au resources of Central Europe with Au reserves of more than 100 t proven during exploration between 1970 and 1990. In 1997 Au exploration and a mining project at Mokrsko (CZ) were cancelled owing to mounting public pressure. During the main ore stage (east–west compression) at Mokrsko, parallel and regularly spaced quartz veinlets formed and were filled by quartz, pyrite, pyrrhotite and arsenopyrite. Corresponding fluids belong to a fluid system enriched in C, N, O and H and probably resulted from fluid–rock interactions within the metamorphic series at high-pressue/hightemperature conditions (T ¼ c. 450–5508C and P ¼ c. 250– 400 MPa) (Boiron et al. 2001). Arsenic content of the ore material is up to 1%. Most of the veins are categorized as mesothermal Au veins (Zacharia´sˇ et al. 2004). Stein et al. (1998b) suggest that the emplacement of Au lodes in the Proterozoic and Lower Palaeozoic high-grade metamorphic rocks occurred at the Devonian–Carboniferous boundary. A porphyrystyle model has been suggested to explain the Petrackova Au mineralization (CZ) (Zacharias et al. 2001). In the Vosges-Black Forest basement a few stibnite veins have been mined for several decades. Charbes (F), located near the Saxothuringian-Moldanubian border, is barren with respect to Au but strongly enriched in Pb (Coulombeau 1980). Quartz veins with pyrite, stibnite, tetrahedrite and arsenopyrite at Mu¨nstergrund (D), St. Ulrich (D) and Sulzburg (D) are bound to a graben which subsided into the basement gneisses of the Moldanubian Zone and was filled with sediments of Carboniferous age. These stibnite veins contain only minor amounts of Au (Gehlen 1989). These vein-type deposits evolved in course of the structural segmentation of this Moldanubian basement during the Late Carboniferous and are definitely older than the Cenozoic Pb–Zn veins discussed later in the context of the post-Variscan unconformity. In the Rhenohercynian Zone, at the NW edge of the Variscan orogen, thrust-bound metamorphogenic mineralization occurs at a very shallow structural level in the form of schistosity veins mainly containing Pb and Zn, whereas in the Moldanubian Zone, the core zone of the Central European Variscan orogen, mineralized linear structures bridge the gap between thrust-bound and granite-related deposits sensu stricto. Not surprisingly, W, Sn and U mineralization is, locally, associated with Sb, Hg and Au in vein mineralizations along the SE boundary of the Tepla´Barrandian Zone such as in the environs of Prˇibram (CZ). A large Sb–Au–As province also extends across the Western Carpathians which is the Alpine metallogenic province closest to the Variscan Bohemian Massif. The most well-known deposits of this type are located in the Lesser Carpathians (Tatricum). In the Pezinok-Kola´rsky Vrch Deposit (north Bratislava) (SK) stibniteand Au-bearing mineralization is confined to black shales (Chovan et al. 1992). The physicochemical parameters are as follows: T ¼ 150–3208C, P ¼ 3.5 kbar (Chovan et al. 1995); sulphide 34 S ¼ –1 to –13‰; 13 C ¼ –11.8 to –9.7‰; 18 O ¼ –17.5 to –13.6‰ (Andra´sˇ 1983).

The main Sb–Au–As ore fields in the Gemericum are in the ˇ ucˇma area (SK) where veins with 2–15% Sb, 0.2– Betliar–C 2.2 g/t Au (in the Klement vein 10–20 g/t Au and 13–40 g/t Ag) occur. Further ore-mining districts are at Bystry´ potok (SK) (18– 24% Sb), Poprocˇ (SK) (1.8–6.8% Sb, 3 g/t Au, 27–151 g/t Ag) and in the Zlata´ Idka ore field (SK) which is transitional with the Siegerland-type siderite–sulphide-type mineralization (Grecula et al. 1995) discussed previously. In the Low Tatra Mountains Sb–Au veins and impregnations were mined at Du´brava (SK), Magurka (SK), Medzibrod (SK), Lom (SK) and Dve Vody (SK) (1–3% Sb, 1 g/t Au). These deposits are aligned along deep-seated mylonite zones intersecting Variscan granitoids, metamorphic rocks and migmatites. Sulphur isotopes (34 S(CDT) ¼ 0.6–1.9‰) of pyrite suggest a mantle source for sulphur. Molybdenite, scheelite and arsenopyrite, associated with the Sb mineralization, crystallized from solutions at temperatures between 315 and 3558C and a pressure of more than 2 kbar; such conditions are typical of the metamorphic conditions in that area (Chovan et al. 1995). High CaCl2 contents found in fluid inclusions of barite are indicative of evaporite-derived solutions (Chovan et al. 1995). They probably originated from Permo-Triassic evaporites thus suggesting an upper limit to the age of formation of Sb mineralization. The black schists in the country-rocks are likely to have been the source of elements which were mobilized during metamorphism to amphibolite-facies grade (Radvanec et al. 2004a). All stibnite veins are bound to mylonitic shear zones and understood to be synkinematic relative to the deformation of the country-rocks. Alpine-age fault zones found in the area are barren with respect to Sb mineralization and did not act as conduits for the orebearing fluids (Slavkay & Petro 1993). Many of the shear-zone-hosted stibnite deposits can be attributed to the greywacke- or turbidite-hosted mesothermal Au (Sb) lodes in Upper Proterozoic and Palaeozoic sequences of backarc basins, which are sediment-dominated and lack thick volcanic sequences (Hutchinson 1987; Madu et al. 1990; Dill et al. 1997). This categorization is mainly based on vein mineralization and structural and textural features observed in these vein-type deposits. Recently, a model for the Au vein mineralization in Central Europe was proposed by Boiron et al. (2003), involving the mixing of metamorphic and surficial fluids in the upper crust and hydrocarbon migration. Gold–tungsten vein deposits Thrust-bound Au–W mineralization was recorded from the Carpathians, where vein-type scheelite and Au mineralizations are known from the Tatricum and Veporicum areas. At JasenieKysla´ (SK) Au and W mineralization is found mainly in quartz veins (Pecho 1980). Three types of ore mineralization have been distinguished: (1) hydrothermal veins and stockwork-type mineralization; (2) impregnation zones occurring along the main fault zone with intensive wall-rock silicification; and (3) disseminated scheelite most frequently in amphibolites (Mola´k & Pecho 1983; Pulec et al. 1983). The latter type is subeconomic grade. Two vein-type Au deposits in the Swiss Alps at Salanfe (CH) and Astano (CH) are grouped under this heading of thrust-bound Au–W deposits. At Salanfe sulphides and arsenides together with Au were found in a scheelite-bearing skarn of the Aiguilles Rouges Massif (Chiaradia 2003). Anatexis and leucogranite formation occurred at peak metamorphic conditions (P ¼ 0.45 Gpa, T ¼ c. 650–7008C). This metamorphic event, dated at 317 Ma in the adjacent Mont Blanc Massif, was related to dextral transpression following Variscan continental collision. Structural evidence

FOSSIL FUELS, ORE AND INDUSTRIAL MINERALS indicates that the initial stages of skarn formation also occurred under the above P-T conditions (Chiaradia 2003), suggesting a Variscan formation age. The Salanfe skarns were formed at deep crustal levels by fluids in equilibrium with an anatectic leucogranite, possibly channelled along permeable paragneiss during regional-scale transpression. Astano (CH) is located east of Lago Maggiore in the Southern Alps and contains a typical Au–(Sb) vein-type mineralization with a variegated spectrum of Sb sulphides. Here, the complicated polyphase metamorphic history inducing several stages of high-temperature Alpine remobilization makes it difficult to derive any information on the genesis of the deposit. Ko¨ppel (1966) suggested that it is a mesothermal Au–Sb deposit with Au being accommodated in the arsenopyrite and pyrite lattices as ‘invisible Au’ and present as native Au or electrum. This element combination is similar to the Variscan thrust-bound Au–As–Sb vein-type deposits in the extra-Alpine part of Central Europe. Therefore, a Variscan age of the Astano deposit seems plausible. However, the mineralogy of the vein-type deposits in the Alps is different from that in the extra-Alpine deposits. For example, Sbbearing sulphosalts (e.g. jamesonite, boulangerite, zinkenite) are more common than stibnite in the Alps, and monotonous quartz–stibnite veins, very common to the Rhenohercynian and Saxothuringian zones, are absent. Therefore, the age of formation is still problematic. Thrust-bound talc and asbestos deposits in (ultra)basic igneous rocks Retrograde metamorphism was responsible for the talc mineralization in basic and ultrabasic rocks located along the margin of the Mu¨nchberg Gneiss Complex (e.g. Schwarzenbach/Saale (D), Wirsberg (D), Erbendorf (D)). The klippen of the ErbendorfVohenstrauß Zone and the Mu¨nchberg Gneiss Complex, a previously coherent eclogite-bearing nappe complex with medium-pressue metamorphics, were strongly deformed during emplacement. During the final (retrograde) stages of structural deformation thrust-bound metamorphogenic deposits, e.g. pegmatitic mobilizates, Au–(Te)-bearing veinlets and talc-bearing shear zones, developed along the southern edge and within the Mu¨nchberg Gneiss Complex (Dill 1979, 1981). In some places in the Moldanubian Zone (e.g. Hoher Bogen near Neunkirchen (D)), late-stage hydrothermal alteration of Proterozoic (ultra)basic rocks was accountable for asbestos mineralization developing along shear zones. Asbestos mineralization of this kind, however, was relatively moderate with respect to quantity, and was of inferior quality, so that its deposits have been mined only during wartime. This is also true for the chrysotile and actinolite mineralization in the Rhenish Massif (D) and the Frankonian Massif (D). These were emplaced during the later stages of diabase magmatic activity at the end of the Devonian. Feldspar–quartz pegmatoids and quartz lodes In the Variscan orogen, heat production reached its climax during the Late Carboniferous and the concentration of rare elements reached a maximum in the highly differentiated granites and pegmatites. These coarse-grained pegmatitic mobilizates (discussed in the next section) have precursors of metamorphogenic origin. Unlike their granite-related successors, the metamorphogenic mobilizates lack both mineral zoning and rare elements. A simple mineralogy with garnet and tourmaline as the only ‘rare element accessories’ and little segregation of feldspar and quartz are observed in the metapegmatites in the Oberpfalz in the Klobenreuth and Wendersreuth mines (D) and the Rotgneis of

35

the Erzgebirge (D) (Teuscher & Weinelt 1972). Pegmatoid schlieren and patches with up to 80% albite and 20% quartz have also been mined for abrasives at more than 30 locations for several decades by open-cast and underground mining in the Mu¨nchberg Gneiss Complex (Bauberger 1957; Dill 1979). Investigations on metamorphogenic types of pegmatitic mobilizates and their metabasic country-rocks (banded amphibole gneisses) were carried out by Okrusch et al. (1991). Their studies suggested maximum formation temperatures of 620 308C for the banded amphibole gneisses. White mica, interstitial to the framework silicates of the pegmatites, suggested a formation temperature greater than 4008C for the quartz–feldspar association. The structural conformity of these mobilizates with the textures of the enclosing country-rocks suggests that pegmatitization was contemporaneous with country-rock deformation. Further to the south in the Bohemian Massif, the Bavarian Fault (Bayrischer Pfahl or Great Bavarian Quartz Lode (D)) occurs together with some smaller, but structurally equivalent fault zones in the western part of the Czech Republic. The steeply dipping Bavarian Fault is one of the most prominent shear zones in the Varican orogen, which was reactivated during the Permo-Carboniferous (Zulauf et al. 2002). Open-cast operations for quartz are found at various locations along this quartz lode. Non-metallic deposits of this type are also found in the Dinarides, where numerous pegmatitic mobilizates evolved in the migmatites of the Papuk Mountain (HR), the most extensive of which is Dukina Kosa with feldspars and muscovite as major minerals. In addition, there are quartz lenses and veins of synand post-kinematic secretional origin, termed Alpine-type veins (Jurkovic´ 1962).

Collision (granite)-related deposits Late stages of Variscan convergence in mid-Carboniferous times resulted in the emplacement of abundant synorogenic granites (Seltmann & Faragher 1994; Henk et al. 2000; Kroner et al. 2008). Petrological data point at 600–8508C at upper- to midcrustal levels. Radiogenic heating in the thickened continental crust is considered as the main heat source. Simultaneously, processes such as convective removal of the thermal boundary layer, delamination of part of the lithospheric mantle or subduction of mantle lithosphere must have prevented the thickening of the mantle (Henk et al. 2000; see Kroner et al. (2008) for more details on Variscan-age magmatic activity). Arc-related plutonism occurred during mid-Carboniferous times (340–325 Ma) along the Mid-German Crystalline High as the active SE margin of the Rhenoherynian Zone (McCann et al. 2008b). Highly fractionated S- and I-type granites are the most fertile granites since they contain the essential fluids to create U, Sn, F, P, Li, Nb and Ta mineralizations. Mineralization of this set of elements can be traced from the Massif Central in France, through the Erzgebirge Mountains in Germany (Cuney et al. 1992; Sˇtemprok & Seltmann 1994; Fo¨rster et al. 1998, 1999; Marinac & Cuney 1999). Small ore bodies containing Ni–Cu sulphides are bound to more basic predecessors of these granites (Walther & Dill 1995). Disseminated nickel–copper deposits Nickel and Cu mineralization evolved in the Harzburg Gabbro in the Harz Mountains (D). Pentlandite, pyrite and chalcopyrite constitute the major ore minerals in a partially anatectic hornfels with average contents of the disseminated and lense-shaped Ni– Cu ore bodies standing at 0.7% Ni and 0.3% Cu (Walther 1986;

36

H. G. DILL ET AL.

Walther & Dill 1995). The geochemical characteristics of the magma are similar to those of an island-arc tholeiite, characterized by low TiO2 and alkalis and high Al2 O3. Geochemical and Pb, Sr and Nd isotope data demonstrate that even the most primitive rocks have assimilated crustal material. Petrographic, geochemical and isotope evidence demonstrates that during a late stage of crystallization, hybrid rocks formed through the mechanical mixing of early cumulates and melts with strong crustal contamination from the upper levels of the magma chamber (Sano et al. 2002). The mode of formation of Ni–Cu ore in the Harzburg Gabbro is similar to that described as Sudbury type. Intrusive diabases and picrites of Early Carboniferous age evolved in the Lahn-Dill area (D). In addition to partial serpentinization of these intrusive basic and ultrabasic igneous rocks, subeconomic-grade millerite, chalcopyrite and pyrite crystallized in these alteration zones. Tin–tungsten–molybdenum vein-type, greisen and skarn deposits Granite-related Sn-W mineralization occurs along the Czech– German border in the Erzgebirge Mountains leading to the formation of a large metallogenetic province matched in Europe only by the Cornwall Sn district (Breiter et al. 1999). In greisen zones in the cupola of the granites (e.g. Altenberg (D)), cassiterite was concentrated. Particular attention should be drawn to the Poehla-Haemmerlein deposit at Gottesberg (D), which is a large, low-grade, refractory Sn skarn. Its reserves have been reported as 12.3 Mt averaging 0.42% Sn (Buder et al. 1993). Scheelite is present in skarns which developed in Lower Palaeozoic limestones (e.g. Sparnberg-Pottiga (D), Go¨pfersgru¨n (D)). Locally, very complex mineralization developed (such as at Obrˇ´ı Du˚l (CZ)) with scheelite superimposed on a high-temperature mineral assemblage of cassiterite, stannite, malayaite, stockesite and Sn-bearing garnet (Mochnacka et al. 1995). Wolframite predominates in quartz veins (Kra´sno (CZ), Ehrenfriedersdorf (D), Altenberg (D), Zinnwald-Cıńovec (D/CZ), Pechtelsgru¨n (D)) (Fig. 21.10). Cassiterite and wolframite in the Erzgebirge area are almost exclusively related to the younger granites (older granites, 330– 310 Ma; younger granites, 305–290 Ma) (Baumann et al. 1986; Seltmann & Faragher 1994; Tischendorf et al. 1995; Breiter et al. 1999; Webster et al. 2004). However, there are obvious exceptions from the rule: for example, radiometric age dating by

Fig. 21.10. The classic greisen stock at Altenberg (D) (Baumann 1965).

Kempe & Belyatsky (1997), using the 144 Nd/143 Nd and 147 Sm– 144 Nd methods, yielded a Namurian formation age (321– 326 Ma) for the Sadisdorf Sn–W mineralization (D). Tin-W mineralization occurs in the endo- and exocontact area of the Sn–F–Li granites and may locally extend into the pegmatitic bodies related to these Late Variscan granites (Thomas & Webster 2001). The Altenberg (D) and Zinnwald/Cıńovec (D/ CZ) deposits are among the best known Sn deposits of Europe (Baumann et al. 2000). Tin mining in the Erzgebirge dates back to the twelfth century and came to an end in 1991. The total Sn production from the Erzgebirge was 300 000 t, and the corresponding production figures for W are 21 400 t (Freels et al. 1995). The Altenberg Sn deposit is located in the contact zone of the Altenberg granite porphyry and the Teplice quartz porphyry. The Altenberg granite forms a stock-shaped intrusion in the granite porphyry with extensive greisen zones measuring 300 to 400 m in diameter and 230 m in vertical extension. Greisen refers to pervasively altered lithium–albite granite in which feldspar and biotite are converted to a disseminated assemblage of quartz, topaz, muscovite, zinnwaldite and protolithionite (both Li-micas), cassiterite, sericite, fluorite, dickite, kaolinite, wolframite and scheelite. Pegmatitic parts altered to topaz (pycnite), zinnwaldite and quartz are called ‘Stockscheider’. The main ore minerals are cassiterite, wolframite and molybdenite (Baumann et al. 1986). Mining commenced in 1620 with the opening up of the Great Pinge (Fig. 21.10). The Zinnwald/Cıńovec Sn–W–Li deposit consists of a system of regular veins in greisenized zones of a granite body, with quartz, wolframite, scheelite, cassiterite, zinnwaldite, topaz, fluorite, muscovite, Li-mica and feldspar forming the main mineral in the greisen zone. The Saxothuringian and Moldanubian zones in the Vosges and the Black Forest contain no significant Sn deposits, although some Sn minerals may be found in the Triberg Granite (D). The Vosges contain W mineralizations in their northernmost part, near Framont Grandfontaine (F), where an Fe-bearing scheelite skarn was examined by the Bureau de recherches geólogiques et minie`res (BRGM) and Mo accumulation near Breitenbach (F) (Bouladon 1989). The situation is similar in the Massif Central, where some W mineralization is known, but Sn deposits are absent.

FOSSIL FUELS, ORE AND INDUSTRIAL MINERALS In contrast to the Saxothuringian and Moldanubian zones, the Rhenohercynian Zone contains neither W nor Sn deposits. In the Variscan Aar Granite of the Swiss Alps, molybdeniteand scheelite-bearing quartz veins occur in the Baltschiedertal (CH) (Jaffe´ 1986). In the Mittersill W deposit (Eastern Alps) (A), Variscan-age magmatism (340 Ma) is considered to have been responsible for a second phase of scheelite mineralization which was superimposed on the primary Early Palaeozoic phase (Eichhorn et al. 1999; see section on Precambrian–Cambrian strata-bound deposits above). In the Carpathians (Gemericum) granite-related Sn–W–Mo deposits were encountered in the fine-grained two-mica granite near Hnilec (SK) and at Rochovce (SK). The apical parts of the granites are greisenized and rich in B, F, Li, Rb, Cs, Be, Mo and Sn (Broska & Uher 2001). Based upon high initial Sr isotope ratios (ISr ¼ 0.711–0.715) which are accompanied by higher åNd(i) of –4.6, elevated stable isotopes values of 18 O(VSMOW) (10‰) and 34 S(CDT) (4.48‰), a mature continental metasedimentary protolith can be assumed for these granites (Kohu´t & Recio 2002). A Late Variscan formation age may be concluded from the data obtained from radiometric age dating of monazite (276 13 Ma and 263 29 Ma; Finger & Broska 1999; Finger et al. 2003), single-grain U–Pb zircon dating (250 18 Ma; Poller et al. 2002), and the Re–Os method on molybdenite (262.2 0.9 and 263.8 0.8 Ma; Kohu´t & Stein 2005). Lead–copper–zinc–silver vein deposits Lead, Cu, Zn sulphides and Ag-enriched tetrahedrite (¼ freibergite) and Sb sulphosalts as well as native Ag and argentite were emplaced in the Erzgebirge, e.g. at Freiberg (D) and Schneeberg (D) (Tischendorf et al. 1995; Baumann et al. 2000). Freiberg mining district. Silver mining near Freiberg was described as early as 1168 and continued until 1968. During this time period, about 14 Mt of Pb and Zn with 5200 t of Ag metal have been produced. The vein-type base-metal mineralizations are younger than the Sn-bearing mineralization. More than 1000 veins, cross-cutting and with a range of orientations, were mapped in the upper Proterozoic gneisses. These veins are famous for the presence of argyrodite (Ag8 GeS6 ) which was used to extract the metal Ge. Argyrodite, as mined in Freiberg, contains 1.8 to 6.9% Ge. These veins have been considered to result from differentiation of magma with the development of a volatile fluid phase that escaped along faults to form the veins. More recently, researchers have preferred to invoke mixing of cooler, upper-crustal hydrothermal or meteoric waters with rising fluids that could be groundwater heated by an intrusion or expelled directly from a differentiating magma (Baumann et al. 2000). Another representative of the Variscan polymetallic Agenriched Pb–Zn vein deposits is situated in the Moldanubian Zone of the Bohemian Massif where a set of parallel veins cuts through gneisses and migmatites of the Kutna´ Hora Crystalline Complex (CZ) (Pouba & Ilavsky´ 1986). A conspicuous zonality may be recognized in the region around Kutna´ Hora, with Sb, Pb and Zn minerals being concentrated in the S, Pb, Ag and Zn in the central parts and Cu, As, Fe, Zn and Sn in the north. This is a classic example of how Sb-dominated thrust-bound mineralization gradually changes via Pb–Zn mineralization into Sn mineralization. Small Pb–Zn vein-type deposits, with arsenopyrite, chalcopyrite, quartz and calcite, have been mined in the metamorphic envelope of the Gotthard (Bristenstock (CH)) and Aar massifs (Alp Nade`ls (CH)) in the Swiss Alps (Jaffe´ 1986). Although they

37

are mineralogically less variable than the Erzgebirge Pb–Zn deposits, the Swiss vein deposits have been correlated by Jaffe´ (1986) with the ‘kiesige Bleiformation’ at Freiberg. The Trachsellaunen (CH) and Groppenstein (CH) Pb–Zn vein-type deposits are also located in the Aar Massif. What distinguishes them from the adjacent Pb–Zn deposits is the presence of fluorite and barite. The ubiquity of F and Ba in these veins is taken as evidence for Alpidic mineralization being superimposed on Variscan Pb–Zn mineralization. Polymetallic and monotonous uranium vein-type deposits Much effort and money were spent on U exploration and exploitation in Germany, France and in the former Czechoslovakia over the last century. Based on mineral composition, the fault-bounded Variscan U mineralization may be subdivided into a monotonous mineral association comprising pitchblende with coffinite, brannerite, U leucoxen, U-bearing carbonaceous matter and some molybdenite (e.g. Ma¨hring (D) and Chateau-Lambert (F)) and a polymetallic mineral association with pitchblende associated with Pb, Bi, Cu selenides as diagnostic minerals (e.g. Erzgebirge U deposits). The polymetallic mineral association is genetically related to the intrusion of high-heat-production (HHP) granites. The metals involved in the mineralization and part of the aqueous solutions were mixed with meteoric waters percolating through these granitic bodies. The best known U deposits in Central Europe are located in the Saxothuringian Zone. In the eastern part of the Saxothuringian Zone (Lugian Zone), polymetallic U deposits were discovered in the Kletno (PL) and Kowary (PL) areas (Piestrzynski 1997). Here, pitchblende and coffinite are accompanied by Co, Ni, As, Bi, Cu, Pb, Zn and Se minerals. A member of the ‘monotonous U mineral association’ is brannerite which was reported from quartz veins cutting through leucogranites near Kowary (PL) (Mochnacka et al. 1995). Uranium bearing fluorite veins are common in the Izera Gneiss Complex (Western Sudetes). Several U vein-type deposits are located on both sides of the Czech–German border along the Erzgebirge area at Jaćhymov (CZ), Hartenstein (D), Aue (D) and Oberschlema (D) (Tischendorf et al. 1995; Ondrus et al. 2003; Fo¨rster et al. 2004). The mineralogy of the U vein-type mineralization from the Erzgebirge was studied by Fo¨rster (1999). Based upon the occurrence of selenides (Fo¨rster et al. 2004), the mineralization can be attributed to the ‘polymetallic U mineral association’ (Bana´s 1991). Dating by U–Pb gives a formation age as early as 265 Ma (Mochnacka et al. 1995). Jaćhymov (CZ) shows a wealth of minerals. About 180 mineralized veins in mica schist and phyllite around a granite massif contain Ag, U and minor amounts of Bi, Co, Ni, Zn, Pb, Cu, Sb and As. The veins contain pitchblende, Ag-bearing sulphoarsenides and native Ag, along with other rare minerals and more common sulphides. Mining in the Jaćhymov ore district began in 1516, and developed into one of the largest mining centres of Europe. The word ‘dollar’ originated from the German word ‘Thaler’ (Joachimsthal). At the end of the nineteenth century, radioactivity was studied intensively on Jaćhymov U ores and resulted in the discovery of radium. Further to the west at Grossschloppen (D) and Hebanz (D) in the Fichtelgbirge area, silicified and episyenitic vein structures were investigated by drilling operations and test mining (Fig. 21.2d). In granites undergoing episyenitization, quartz is replaced either by dolomite or by calcite mineralized with U minerals. Another type of episyenite-bearing zeolite, mainly heulandite and stilbite, contains no U mineralization. Episyenitization is

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associated with Mg metasomatism of metacarbonate-bearing horizons subjacent to the U mineralization (Dill 1986b). Towards the south, test mining was carried out at Hoehensteinweg (D) and Ma¨hring (D), where U mineralization is associated with fracture zones and quartz lodes. These extend across the border into the Czech Republic and were mined near Dylenˇ (CZ) and Zadnı´ Chodov (CZ). Hydrocarbon migration along faults is a major control on the precipitation of U minerals in vein mineralization. This has been shown by the various types of impsonite (epi- to kata-type) in the German U vein-type deposits as well as by results obtained during chemical investigations in the Prˇibram mining district (CZ) (Dill & Weiser 1981; Krˇ´ıbek et al. 1999). The origin of some U mineralization in the eastern part of the Bohemian Massif can also be associated with an infiltration of basinal brines which extracted U from U-bearing accessories in Upper Carboniferous to Lower Permian clastic rocks. The veintype and disseminated-type U deposits of Rozˇna´-Olsˇi (CZ), bearing minerals of the monotonous and polymetallic U mineral assemblages, are transitional from granite- to unconformityrelated deposits and pertain to one of the mineralizations bridging the gap between the Variscan and Alpine metallogenetic cycles (Krˇ´ıbek et al. 2005). Between 1954 and 2005 the total production from these deposits reached 20 000 t U. Uranium vein mineralizations are associated with a variegated spectrum of metallic and non-metallic mineralizations such as at Nabburg-Wo¨lsendorf (fluorite) (D), where a peculiar type of U mineralization was discovered at several sites in the Oberpfalz. The so-called Schwarzach U ores form part of the polymetallic U mineralization with pitchblende and Cu selenides (Dill 1983). What makes them distinct from their other counterparts in NE Bavaria is the massive yellow U ore mineralization with ‘gummites’ so far not discovered anywhere else in Central Europe. In the Black Forest U vein mineralizations are associated with fluorite at Menzenschwand (D) and with Bi and Co sulphides at Wittichen (D) (Gehlen 1989). The Variscan U belt also extends into France, where vein-type mineralization was extensively studied and operated until recently in the Vosges near Chateau-Lambert (F) (Bouladon 1989) and in the Massif Central, e.g. Magnac (F) and Funay (F) (Leroy 1978). Variscan-age U mineralization is also preserved during Alpine tectonic remobilization in the Tavetsch Massif near Trun (CH) in the Swiss Alps. Similar U showings were also discovered in the gneissic envelope of the Variscan Aar Massif (Naters (CH) and in the Aiguilles Rouge Massif at Le Chatelard (CH). The oldest pitchblende in the vein-type deposits in northern Bavaria (Fichtelgebirge, Oberpfalz) (D) have yielded an upper intercept in the concordia plot at 295 4 Ma (Carl et al. 1983). The post-tectonic granites from the Fichtelgebirge have been dated at 320 to 280 Ma (Wendt et al. 1988). These radiometric data show a genetic link between U mineralization and the Late Variscan igneous activity. Investigation of the pitchblende from the Menzenschwand area (Black Forest) by U–Pb indicates a Variscan formation age (310 3.5 Ma) for at least the earliest mineralization. The pitchblende from Wittichen (D) yielded an age of 235 5 Ma corresponding to a younger reshuffling of radioisotopes. Studies in the Massif Central suggest that the conduits for the U-bearing solution might have acted more than 20–30 Ma after trap formation as preferential channel ways and radiometric age data indicate the longevity of hydrothermal circulation processes driven by exhumation (extension) and uplift in and around these granites. The initiation of regional uplift at c. 320 Ma triggered the circulation of in-situ derived low-density

aqueous fluids at depth, that then reacted with the granite to form large vertical dissolution conduits (episyenites; Scaillet et al. 1996). The hydrothermal alteration was further enhanced during uplift by the structurally focused flow of large volumes of aqueous fluids along brittle faults cutting across the laccolith. Due to sustained hydrothermal circulation adjacent to terminal HHP injections, these conduits acted over a long time as preferential channels for the U-bearing fluids and resulted in the emplacement of U deposits along vertical fault zones and in the metasomatic columns. The longevity of U-ore deposition is particularily remarkable, since it helps to bridge the gap between the Late Variscan granite-related deposits and some of the unconformity-related Ubearing deposits associated with the post-Variscan unconformity. It may also account for the precipitation of Late Palaeozoic U oxides during the early stages of vein formation in the NabburgWo¨lsendorf Fluorite District (D) and for the Late Variscan fetid fluorite or antozonite (German: Stinkspat) that was chronologically constrained by Sm–Nd isotope analyses to between 296.6 23.2 and 281.2 22.9 (Leipziger 1986). Feldspar–quartz and polymetallic lithium–niobium–tantalum pegmatites During the collisional stage of the Variscan Orogeny several pegmatites were emplaced in the Moldanubian Zone. Complex quartz–feldspar pegmatites, which have been the object of longterm mining operations and are still attractive for mineral collectors because of their mineral wealth, are situated at Hagendorf (D), Pleystein (D) and Waidhaus (D). The most prominent of these, at Hagendorf-South, shows well-developed zoning with an aplitic margin, a pegmatitic inner zone, a quartz core and a cone-shaped body with Li phosphates, Nb, Ta, U and numerous other rare element minerals (Mu¨cke 1987, 2000; Mu¨cke et al. 1990). Between 1960 and 1972, 1000 t of Li ore were extracted mainly from triphyline as a byproduct of the running feldspar exploitation which is based on 8 Mt of feldspar–quartz ore. In 1983 the mining operation for feldspar and quartz proved to be no longer profitable. This chain of pegmatites may be extended through the Czech Republic into Poland with lepidolite pegmatite near Rozˇna´ and Dobra´ Voda (CZ) (Cerny´ et al. 1995; Nova´k & Cerny´ 2001), beryl columbite pegmatites near Scheibengraben (CZ) (Nova´k et al. 2003), and niobite–tantalite pegmatite at Zo´lkiewka (PL) (Janeczek 1996). The composition of microlite-type minerals and the textural relations indicate that the hydrothermal stage generating Nb–Ta ore in the pegmatite includes a broad range of P-T-X conditions (where X is composition) from early subsolidus replacement at 500–3508C and 2.5–2.0 kbar at Dobra´ Voda (CZ) to near-surface weathering at temperatures below 1008C (Nova´k & Cerny 1998). Rare-earth element (REE) minerals may be found in addition to topaz in the Late Variscan granites as shown by new data from the Karlovy Vary Pluton (CZ) (Kempe et al. 2001) and from the Trˇebıćˇ Pluton (CZ) where thorium mineralization was discovered by Sulovsky´ & Hlisnikovsky´ (2001). Talc (soapstone) replacement deposits in carbonate rocks Soapstone/talc deposits associated with the (?Pre-)Cambrian-age Wunsiedel Marble have been worked at numerous sites in the Fichtelgebirge near Go¨pfersgru¨n (D) as a raw material for products ranging from electric insulators to powder in chewing gum production. Before closure of the last open-cast mine in 1997, annual production was 10 000 t and reserves were estimated at 200 000 t of ore (Bayerisches Staatsministerium fu¨r Wirtschaft und Verkehr 1979). The talc deposit at Go¨pfersgru¨n

FOSSIL FUELS, ORE AND INDUSTRIAL MINERALS was formed by hydrothermal alteration of the Wunsiedel Marble probably during Permian times. Hydrothermal talc mineralization occurs along a major fault zone and is associated with the formation of massive saddle dolomite. The main talc mineralization resulted from decarbonation at low XCO2 (where X ¼ male fraction) and temperatures between 250 and 4008C. Hydrothermal dolomitization, talc mineralization and vugs filled with carbonate during the waning stages of alteration are related to formation brines or crustal fluids that interacted with graphitebearing metapelites under acidic conditions (Hecht et al. 1999).

Petroleum deposits Apart from coal-bed methane, hydrocarbons are rare in prePermian rocks in Central Europe. However, a minor oil (and gas) province is located in the Baltic Syneclise. This basin, filled mainly with Lower Palaeozoic rocks, is situated on the western margin of the East European Craton. It forms an approximately oval-shaped interior basin with the SW part of the basin subsiding to 5 km near the Tornquist-Teisseyre Zone. Baltic Syneclise The Baltic Syneclise is situated in the south Baltic Sea and the adjoining onshore areas of Latvia, Lithuania, Poland, and the Russian enclave of Kaliningrad. Exploration activity began in the 1960s and led to the discovery of 20 small- to medium-sized accumulations in Lithuania, one small oil discovery in Latvia and 25 oil discoveries in Poland. Exploration in the Russian sector of the basin has reaped the greatest rewards, including the largest onshore and offshore fields (Krasnoborskoye, Ushakovskoye, Kravtsovskoye), hosting about 60 million barrels each. Peak liquid production has not yet been reached but peak gas production was attained in 1988. In 2001, the daily production reached 30.8 million barrels per day. Small-scale oil production took also place on the Swedish island of Gotland. Following a period of rifting in Late Vendian to Early Cambrian times (Poprawa et al. 1999), post-rift subsidence took place in the Middle Cambrian before being interrupted by uplift associated with arc–continent collision. Renewed subsidence in Early Ordovician times led to the deposition of a thin basal sandstone unit, which is overlain by a thick sequence of Ordovician carbonates and marls. The early Caledonian orogeny is represented by the closure of the Tornquist Sea. Reactivation of the Tornquist-Teiysseye Zone as a transpressive strike-slip fault during the Caledonian Orogeny led to a short period of flysch sedimentation followed by deformation and uplift. MidDevonian to Carboniferous sediments were laid down in a sag basin and were deformed in the Variscan Orogeny (Carboniferous to Permian). Diabase intrusions with a Late Palaeozoic age occur in the area of the Baltic Sea. Overlying sediments are generally thin and of minor importance for hydrocarbons. Lower Silurian shales form the major source unit, but Cambrian and Ordovician sources also contributed to the accumulations (Zdanaviciute & Lazauskiene 2004). With increasing overburden, maturity varies from immature in the NE to postmature in the SW. The principal reservoir unit is the Middle Cambrian Deimena Formation. The shallow-marine sandstones are about 50 m thick and have a 3–15% porosity (Sliaupa et al. 2004). Additional reservoir rocks are Ordovician to Devonian limestones and sandstones. Hydrocarbon accumulations also occur in fractured basement rocks. Seals include Middle Cambrian, Lower to Middle Ordovician and Silurian mudstones and muddy carbonates.

39

An early generation and migration phase occurred in Late Silurian to Devonian times (Zdanaviciute & Lazauskiene 2004). A major period of migration occurred in Late Jurassic to Cretaceous time into reservoirs in the SE and east of the basin. Structures in the basin are related to the major periods of structural activity, i.e. Vendian rifting, Cambrian to Silurian subsidence, Caledonian transpression, Variscan compression, and minor compressive events in Jurassic to Tertiary times.

Alpine cycle Supergene and hypogene deposits related to the postVariscan/Early Alpine unconformity The Variscan Orogeny resulted in deformation, uplift of mountain ranges and major erosion giving rise to the post-Variscan/ Early Alpine unconformity (see Kroner et al. 2008). This unconformity is overlain by rocks ranging in age from Stephanian to Early Jurassic. The hiatus between basement rocks and overlying sediments, therefore, represents different time intervals in different area. Peneplanation and etch planation (Twidale 2002) under semiarid to (sub)tropial climatic conditions occurred during these time intervals. The distribution of the overlying Permo-Mesozoic rocks is controlled by eustacy and tectonic events related to the breakup of Gondwana. Major Permian to Jurassic tectonic events which influenced metallogenesis along the post-Variscan unconformity include: (1) Stephanian to Early Permian rifting accompanied by extensive magmatism; (2) Triassic to Jurassic opening of oceanic domains in the Alpine region; and (3) Mid-Triassic to Early Jurassic extension in the extra-Alpine region (see ScheckWenderoth et al. 2008). Isotope data increasingly show the significance of a thermal event at the Triassic–Jurassic boundary for ore formation in Central Europe (Wernicke & Lippolt 1997a). One of the first discoveries of ‘unconformity-related vein-type deposit’ was made in 1968 in Saskatchewan (Canada), when U was found in Upper Precambrian metasediments near Rabbit Lake. Since then unconformities have been recognized as major hydraulic planes for hypogene U deposits elsewhere in the world (Dahlkamp 1984). Dill (1988a) recognized the post-Variscan unconformity as an important hydraulic plane in Central Europe and discussed its prominent role in relation to the numerous fluorite–barite vein deposits at the western edge of the Bohemian Massif and around the Vosges–Black Forest basement dome. Later, the unconformity model was extended to the Central European Variscan basement and the overlying Meso-Cenozoic platform sediments (Dill 1994). This concept has also been applied for sulphide-, fluorite- and barite-bearing mineralizations elsewhere in Europe (Boni et al. 1992; Rodeghiero et al. 1996; Brigo et al. 2001). The Late Variscan/Early Alpine unconformity has become a geohydraulic plane for a great variety of epigenetic deposits which evolved where this unconformity was intersected by (sub)vertical fault zones (Fig. 21.3c, d). Hypogene (fluorite, barite, Hg, Ag, Cu, Pb, Zn, Sb, U, Mo) deposits related to the post-Variscan unconformities are found within Upper Carboniferous to Lower Jurassic igneous rocks and platform sediments, or immediately beneath the unconformity in Palaeozoic basement rocks. The transition from the Variscan to the Alpine cycle is more distinct in the extra-Alpine part than in the Alpine part of Central Europe, where sedimentation was continuous in some regions. Unconformity-related vein-type deposits grading upwards into strata-bound deposits are thus more widespread in the

40

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Alpine part, whereas strata-bound deposits developed quite separately from unconformity-related vein-type deposits in the extra-Alpine part of Europe. In the Carpathians, Variscan movements continued into the Permian and the post-Variscan unconformity is overlain by Lower Triassic rocks. Here, the complex interplay of per ascensum (metamorphogenic) and per descensum (hydrothermal–unconformity-related) fluids led to the precipitation of siderite and magnesite. Therefore some researchers in the Western Carpathians consider this stage as part of the Variscan metallogenic cycle. Supergene deposits with kaolin, Sn and U are related to peneplanation and etch planation processes (Twidale 2002). In an idealized cross-section from the basement to the lacustrine basin, unconformity-related and strata-bound ore deposits are plotted as a function of different host rock lithologies and depositional environments (Fig. 21.11). Supergene deposits Kaolin saprolite associated with the Early Alpine unconformity. Late Variscan uplift led to extensive erosion as a result of pervasive chemical weathering and denudation of the basement rocks under (sub)tropical climatic conditions, as is currently the case in central Africa, where a thick regolith of kaolin is being formed. Kaolin quarried at Podborˇany (CZ) (Central Bohemian Basin; west of Praha) immediately overlies this unconformity in the form of a palaeoregolith/saprolite or is found redeposited within arkoses and conglomerates of Carboniferous age (Kuzˇvart 1968). The kaolin from the Podborˇany region occurs in feldspathic sandstone of the Lıńeˇ Formation. Climatic conditions favourable for the formation of kaolin prevailed in the Westphalian and Stephanian but extended also into the Mesozoic and even Early Cenozoic times. Kaolin from the Karlovy Vary deposits (CZ), which developed on granite, has few impurities and is of such high quality that it is used in the production of fine china. At the eastern margin of the South German Basin (west Nu¨rnberg) kaolin is currently mined between Hirschau and Schnaittenbach (D) in several open pits with a total production of about 400 000 t kaolin per year (Gilg 2000). The host rocks are Lower Triassic arkoses juxtaposed with granites and gneisses of the Bohemian Massif. Based on stable isotope data, Gilg (2000) assumes an Early Cretaceous kaolinization age. Locally, these kaolinized arkoses contain elevated Pb contents (Ko¨ster 1980). The arenaceous sediments represent the proximal facies of what is mentioned later in relation to the Triassic-age stratabound ore mineralization from the Bleiglanzbank (D) and the Freihung cerussite deposit (D). The Pb in both of these deposits was derived from the weathering of K feldspar in exposed crystalline rocks. In the kaolinitic arkoses, Pb is accommodated in the lattice of plumbogummite (PbAl3 (PO4 )2 (OH)5.H2 O). This secondary mineral thus links the Pb source in the basement rocks with the more distal Pb deposits. Uranium vein-like deposits beneath the Early Alpine unconformity. The most prominent representative of supergene deposits related to the post-Variscan unconformity was mined in the Gera-Ronneburg area (Fig. 21.3a) in the Thuringian-Franconian Massif. The Lower Palaeozoic carbonaceous ‘protore’ rocks or ‘low-metal concentration’ (see section on Ordovician–Silurian strata-bound U deposits) were folded, sheared and uplifted at the end of the Palaeozoic and subjected to chemical weathering from the Late Palaeozoic onward (Lange et al. 1991). The U mineralization is, in places, of ‘yellow ore-type’ consisting mainly of

uraniferous Fe–Al phosphates (wavellite-type) that resulted from the decomposition of pyrite and apatite disseminated in the Silurian and Lower Devonian black shales (e.g. Gra¨fenthal Horst (D)) or of ‘black ore-type’ with sooty pitchblende and sulphides, such as in the Gera-Ronneburg mining district (D). Supergene U redeposition commenced around 240 Ma with the onset of the Late Palaeozoic peneplanation and ceased by the end of the Mesozoic. At that time another unconformity and another type of U deposits, related to the Late Alpine unconformity, evolved near Ko¨nigsstein-Pirna (D). Hypogene deposits Meso- to epithermal polymetallic mercury–precious metal vein-type deposits in volcanosedimentary series. A complex polymetallic mineralization with Hg as the marker element was precipitated in the aftermath of the granite-related mineralization, as calc-alkaline volcanic and subvolcanic rocks were erupted in the Saar-Nahe Basin. The volcanites and their subvolcanic equivalents host Cu deposits near Imsbach (D) and Fischbach (D) and high-quality Hg ore near Obermoschel (D) and Stahlberg (D) (Dreyer 1973, 1975). Mineralization has produced some rather obscure Hg alloys such as belendorffite (Cu7 Hg6 ), paraschachnerite (Ag3 Hg2 ) and schachnerite (Ag1:1 Hg0:9 ). Mining commenced in the early fifteenth century and has made this area one of the leading Hg producers in the world. During the twentieth century Hg mining sites were reopened in 1934 and closed in 1942 due to exhaustion of the ore bodies. Output during this period was c. 250 t of Hg. Almost all of the dacites and rhyolites in the Saar-Nahe Basin contain anomalously high U contents; this has led to extensive exploration which has proved some significant U discoveries (e.g. Bu¨hlskopf/Ellweiler (D)). Mercury is also a common element in some U vein-type deposits along the Erzgebirge Anticline (e.g. Hartenstein (D)), bridging the gap between the true granite-related U deposits and those bound to the subvolcanic and volcanic calc-alkaline equivalents of the Late Variscan granites. Along the SE margin of the Alps, in the area of Ljubljana (SLO), Permo-Carboniferous siliciclastic rocks contain concordant and discordant ore veins with a very variegated mineral assemblage. More than 40 deposits are known in the area of the Litija Anticline (SLO). Unlike their counterparts in extra-Alpine Central Europe, these deposits do not contain granitophile elements such as U. According to their major mineral assemblages, the deposits can be subdivided into different vein types, namely: (1) sphalerite, (2) galena–sphalerite, (3) galena– sphalerite–cinnabar, (4) cinnabar, and (5) stibnite veins. The Litija deposit (SLO) is one of the biggest of its kind in the Sava Nappe and was interpreted by Drovenik et al. (1980) as a meso-epithermal Pb–Zn–Cu–Hg–Ba–Fe deposit. The ore reserves in Litija enabled production of 50 000 t of Pb, 1 t Ag, 42.5 t Hg and 30 000 t barite. The major minerals are galena, sphalerite, chalcopyrite, tetrahedrite, cinnabar, barite and siderite. The 34 S ratios of the sulphide fluctuate around 0.0‰, whereas those of barite are much heavier, at between +17 and +23‰. The veins were filled prior to the deposition of the Middle Permian sediments. The mineralization may be related to the Lower Permian quartz porphyries and keratophyres in the Eastern Alps (Drovenik et al. 1980). In Slovenia, however, volcanic units are absent, although reworked pebbles in the Permian-age Val Gardena Beds provide evidence of their former presence (Drovenik et al. 1980). In the Dinarides, the spectrum of minerals is more variegated than in any other Central European region and the quantity of Au