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Proceedings of the Third Plenary Conference IGCP 610 “From the Caspian to Mediterranean: Environmental Change and Human Response during the Quaternary” (2013 - 2017) http://www.avalon-institute.org/IGCP610/index.php

IGCP 610 Third Plenary Conference and Field Trip, Astrakhan, Russia, 22-30 September, 2015

ENVIRONMENTAL STRESS IN THE DANUBE DELTA FRONT (BLACK SEA) IDENTIFIED FROM BENTHIC FORAMINIFERA Yanko-Hombach, V.1,2, Kondariuk, T.3, and Kovalishina, S. 1, 3

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Department of Physical and Marine Geology, Odessa I.I. Mechnikov National University, 2 Shampansky Per., Odessa 65052, Ukraine 3 [email protected] 2 Avalon Institute of Applied Science, 976 Elgin Ave, Winnipeg MB R3E 1B4, Canada [email protected] 4 Ukrainian Research Centre of Marine Ecology, Ministry of Nature, 89 Frantsuzskiy Blvd., Odessa 65009, Ukraine [email protected]

Keywords: river discharge, ecosystem, salinity, bathymetrical succession Introduction The Danube River forms a huge delta with surface area about 4,152 km² of which 3,446 km² are located in Romania and the rest in Ukraine. The river has numerous channels (branches) in the lower Danube plain, two of which - Sulina (169 km long) and St. George (109 km long) - are located in Romania, and the third one is the Kilia (or Chilia, 104 km long) in Ukraine. This paper represents continuation of our research using foraminifera for tracing environmental stress caused by river discharge. In addition to our data on the Sulina and St. George delta front, prodelta and outer shelf discussed in Yanko-Hombach et al. (2013, 2014, 2015), we present intermediate results of our study in the Kilia delta front sector. The main goal of the study is to discover a degree of environmental stress in bottom ecosystem caused by the river discharge using bathymetrical succession of benthic foraminifera as the main tool. Study Area The study area includes the NW part of the Black Sea shelf adjacent to the Romanian and Ukrainian parts of the Danube delt (Fig. 1). Material and methods The material was collected mainly in the Romanian and Ukranian delta front, which is generally delimited as the area landward of the 20 m bathygraph (Panin and Jipa, 2002), and in the proximal prodelta at water depth up to28.2 m by the Romanian R/V “Mare Nigrum” and Ukrainian vessel “Hermes” in 2012 and 2013, respectively. In total, the bottom sediments were sampled at 11 stations using a 0.135 m2 van Veen grab. The hydrological parameters were measured by the Neil Brown Instrument Systems CTD. The foraminiferal analysis was performed by methods described in YankoHombach (2007) and Yanko-Hombach et al. (2014) in the Micropaleontological Laboratory of Odessa I.I. Mechnikov National University, Ukraine. The grain-size analysis of the superficial (0-2 cm) sediment layer was performed by sieving and elutriation methods (Logvinenko and Sergeeva, 1986) in the Lithological Laboratory of Odessa I.I. Mechnikov National University and Ukrainian Research Centre of Marine Ecology. The reference collection of foraminifera is stored at Paleontological Museum of Odessa I.I. Mechnikov National University. Results and discussion The limited number of live foraminifera did not allow a reliable study of their distributional patterns. Therefore, the total assemblages (live or stained + dead) were investigated. The presence of live specimens in the assemblages shows that these species most likely live in the study area and that their empty tests are mostly autochthonous. No planktonic species were discovered. Benthic foraminifera were found at the majority of the stations except of the shallowest Sts. HS3-8 (-3 m) and HS3-9 (-8.4 m) with the lowest salinity 16.31 psu and 0.68 psu, respectively.

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Figure 1. Study area and location of sampled stations. MN – stations sampled by R/V “Mare Nigrum”, HS3 - stations sampled by vessel “Hermes”.

They are represented by calcareous epifaunal species from two orders Rotaliida and Lagenida, three families Ammoniidae, Elphidiidae, and Nonionidae, five genera and seven Roataliida species (Ammonia compacta Hofker, A. tepida (Cushman), Canalifera parkerae Yanko, Haynesina anglica Murray, Nonion matagordanus Kornfeld, Porosononion subgranosus mediterranicus Yanko). Order Lagenida is represented by only one infaunal species Fissurina lucida (Williamson) that was found at one station (St. MN103-10, water depth 20.7 m) in a very small relative abundance (1.1%). Its presence in the proximal prodelta is difficult to explain and needs an additional study. Species A. tepida dominates at all stations (54-88%). Species P. subgranosus mediterranicus also occurs everywhere but its relative abundance is lower (10-39%) compared to A. tepida. Species A. compacta (31%) is present in the deepest (-28. 2 m) station HS3-5 where simple diversity (5 species) and Shannon-Wiener Index (H'=1.1) are the highest among all other stations (Fig. 2).

Figure 2. Relative abundances of each species at each HS or MN station, showing changes with water depth (top row of numbers) in mbsl

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According to Murray (1991), H' > 2 is typical for brackish water bodies due to the lower salinity compared to marine basins. But the Black Sea itself is not a brackish basin. Low Shannon-Wiener Index values are a result of freshwater influence on foraminifera which are typical marine organisms. However, freshwater discharge does not affect foraminiferal abundance, which is high reaching maximum values of 21,228 individuals per/50 g sediment in the outer distal delta front (Fig. 3).

Figure 3. Abundance of foraminifera at each station.

The following foraminiferal parameters show positive correlation with depth: relative abundance of A. tepida (r=0.79), abundance of foraminifera (r=0.73), simple diversity (r=0.9), Shannon-Wiener Index (r=0.86), and relative abundance of deformed tests (r=0.65). It indicates that distance from the shore/water depth plays the leading role in distribution of foraminifera. However, the water depth by itself is not a controlling ecological parameter, but most other parameters change with depth, thus causing the well-established bathymetrical successions of foraminifera seen in marine basins (Jorissen et al., 2007). In our material, positive correlation with depth is shown by salinity (r=0.75) and transparency (r=0.64); and negative correlation is shown for SiO2 (r=-0.85). The salinity affects the metabolic activity of marine organisms through the total concentration of salts, ratio of various ions, and degree of saturation of dissolved gases, particularly carbon dioxide and oxygen. As such, an increase in salinity should provide most favourable living conditions for foraminifera, which is evident in our data reported above. The main source of SiO2 in aquatic environments are diatoms and silicoflagellates. The former are used by foraminifera for nutrition (Ward et al., 2003). Negative correlation of SiO 2 with water depth shows that diatoms are not abundant in the delta front and proximal prodelta environment. It means that foraminifera must feed upon different food sources, for example, green algae (Chl-a) and associated grazing bacteria (Pascal et al., 2008). In nearshore regions of strong river discharge а substantial portion of the phytoplankton bloom mау reach the bепthos and become an important рагt оf the diet (Pearson and Rosenberg, 1987). Morphological deformities were observed in A. tepida and P. subgranosus mediterranicus only. In the former, the number of deformed teats is twice as high compared to the latter and increases to the delta front edge. It can be related to mixture of fresh and sea water affecting the cytoskeleton. This subject needs an additional study. Conclusions The bathymetrical succession of foraminifera in the Danube delta front and proximal prodelta shows that even over a short distance, it (e.g., 3-28.2 m) it can provide zoning in distribution of the Danube water (or associated parameters such as particulate organic matter and algal cells) and in estimation of 195


the degree of environmental stress. Most stressed are the bottom ecosystems of the proximal delta front. The stress decreases towards the proximal prodelta, and further on to the distal prodelta and outer shelf. This indicates that Danube discharge loses its influence along the depth gradient as was shown previously (Yanko-Hombach et al., 2014a,b). The study continues and detailed results will be presented elsewhere. Acknowledgements This paper is a contribution to EU BLACK SEA ERA.NET-WAPCOAST project "Water pollution prevention options for coastal zones and tourist areas: Application to Danube Delta front area" and “Control of observation during the operation of deep water navigable course of the Danube-Black Sea: sea part" in the frameworks of agreement No40/13 with the Ukrainian Scientific Research Institute of Ecological Problems, Kharkov. This study is a contribution to IGCP 610 project “From the Caspian to Mediterranean: Environment change and human response during the Quaternary”. References Jorissen, F. J., Fontanier, C., and Thomas, E., 2007. Paleoceanographical proxies based on deep-sea benthic foraminiferal assemblage characteristics. In: Proxies in Late Cenozoic Paleoceanography: Pt. 2: Biological tracers and biomarkers, edited by C. Hillaire-Marcel and A. de Vernal, Elsevier, p. 263-326. Logvinenko, N.V. and Sergeeva, E.I. 1986. Metody opredeleniya osadochnykh porod [Methods for determination of sedimentary rocks]. Leningrad, Nedra. 240 p. Murray, J. W. 1991. Ecology and Palaeoecology оf Benthic Foraminifera. – Longman Scientific and Technical Science. 397 p. Panin, A. and Jipa, D. 2002. Danube River sediment ınput and its ınteraction with the north-western Black Sea. Estuarine, Coastal and Shelf Science 54: 551–562. Pascal, P.Y., Dupuya, C., Richard, P, and Niquila, N. 2008. Bacterivory in the common foraminifer Ammonia tepida: Isotope tracer experiment and the controlling factors. Journal of Experimental Marine Biology and Ecology 359(1): 55-61 Pearson, T.H., and Rosenberg, R. 1987. Feast and famine? Structuring factors in marine benthic communities. In: Gee J.H.R., Giller, P.S. (eds) Organisation of communities past and present. 27Th Symposium of the British Ecological Society, Aberystwyth 1986. Blackwell Science, Ltd, Oxford, p 375-395. Ward, J.N., Pond, D.V., and Murray, J.W. 2003. Feeding of benthic foraminifera on diatoms and sewage-derived organic matter: an experimental application of lipid biomarker techniques. Marine Environmental Research 56 (2003) 515–530. Yanko-Hombach, V., 2007. Controversy over Noah’s Flood in the Black Sea: geological and foraminiferal evidence from the shelf. In: Yanko-Hombach, V., Gilbert, A.S., Panin, N., Dolukhanov, P.M. (Eds.), The Black Sea Flood Question: Changes in Coastline, Climate, and Human Settlement. Springer, Dordrecht, pp. 149-203. Yanko-Hombach, V.V, Kondaryuk, T.O., Likhodedova, O.G., Ankindinova, O.V., Motnenko, I. 2014a. Evaluating the influence of river discharge on marine benthic ecosystems using benthic foraminifera and lithology as the main tools, Proceedings of the Second Plenary Conference. IGCP 610 Second Plenary Conference and Field Trip: “From the Caspian to Mediterranean: Environmental Change and Human Response during the Quaternary” (A. Gilbert and V. YankoHombach, eds.), Baku (Azerbaijan), 12-20 October 2014, International Scientific Journal “Stratigraphy and Sedimentology of Oil-Gas Basins”, Baku: “Nafta-Press”, No 1, pp.171-177. Yanko, V.V., Kondaryuk, T.O., Likhodedova, O.G., Motnenko, I. 2014b. Otsenka vliyaniya rechnogo stoka na morskie donnye ecosistemy po bentosnym foraminiferam i litologii donnykh otlozheniy [Evaluating the influence of river discharge on marine bottom ecosystems using benthic foraminifera and lithology from bottom sediments]. Geology and Mineral Resources of the World Ocean 4: 91-117. (In Russian)

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KOSIKA LOCALITY: NEW DATA—STRATIGRAPHY, PALEONTOLOGY, PALEOMAGNETISM (NORTH CASPIAN DEPRESSION, RUSSIA) Zastrozhnov, A.,1 Danukalova, G.,2 Golovachev, M.,3 Tesakov, A.,5 Titov, V.,4 Simakova, A.,5 Aleksandrova, G.,5 Osipova, E.,2 Yakovlev, A.,2 Fomin, V.,6 and Guzhikov, A.6 1

All-Russian Geological Research Institute (VSEGEI), 74, Sredny prospect, 199106, St. Petersburg, Russia 1 [email protected] 2 Institute of Geology USС RAS, 16/2, K. Marx str, 450077, Ufa, Russia, Kazan Federal University, 18, Kremlyovskaya Str, 420008, Kazan, Russia 2 [email protected], [email protected], [email protected] 3 OGBUK “Astrakhan Museum-Reserve,” 15, Sovetskaya Str., 414000, Astrakhan, Russia 3 [email protected] 4 Institute of Arid Zones SSC RAS, Southern Scientific Centre RAS, 41, Chehova Str., 344006, Rostov-on-Don, Russia 4 [email protected] 5 Geological Institute RAS, 7, Pyzhevsky lane, 119017, Moscow, Russia 5 [email protected] [email protected] [email protected] 6 Saratov State University, 83, Astrakhanskaya Str., 410012, Saratov, Russia 6 [email protected]

Keywords: Lower Volga, Late Neopleistocene (Pleistocene), mammals, palynology, mollusks Introduction Kosika locality is situated on the right bank of the Enotaevka River, left channel of the Volga River near the village of Kosika (Astrakhan Region, Russia). This is a combined locality integrating several sections named Kosika 1-4, and the borehole 2 Kosika. Drilling, description, and sampling for biostratigraphic and paleomagnetic investigations were conducted by the authors during fieldwork in 2013-2014. Though the Quaternary deposits of the Lower Volga area have been described in detail at numerous sites (Shkatova, 1973; Smagin et al., 1977; Sedaikin, 1988; Yanina, 2005; and many others), the Kosika locality, studied now for the first time, adds important reference materials to the Quaternary stratigraphy of the Lower Volga area. Material and methods Excavations and sampling for palynology, fauna, and paleomagnetism followed standard methods. Samples in the Kosika 1 section were taken from the excavation trenches with increments of 10-20 cm, and then they were subdivided into subsamples for palynological and fauna investigations. Additionally, bulk samples were taken in order to obtain mammalian remains. Samples for faunal investigations were washed using sieves of 0.5-1.0 mm. Large mammal remains were excavated from the Kosika 2 section. A total of 62 palynological samples (borehole 2 Kosika) were completely examined. For each sample, the quantity of pollen and spores is given in the pollen diagrams as: “Total sum of SP grains in sample.” The base of the calculation of the percentages for various taxa is the sum of all the grains of pollen and spores (100%) found in sample. Spore and pollen analysis was made for deposits of different sources. 68 samples from the borehole 2 Kosika were paleomagnetically investigated. The authors use the general stratigraphic subdivisions of the Russian Stratigraphic Scale (Zhamoida et al., 2006). Results 1. Stratigraphy Stratigraphic subdivision of the Quaternary deposits was based on facies lithology, biostratigraphic, and paleomagnetic data. Review of the summary deposit description is as follows.

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Lower Neopleistocene. Tyurkyan Horizon. Brownish-grey silty clay with shells of freshwater mollusks (thickness is 30 m) and dark grey clay with lumpy texture layer (hydromorphic soil?; 1 m thick). Erosional surface. Grey clayish sand (thickness is 8 m). Baku Horizon. Dark grey and grey clay (thickness is 26.5 m). Erosional surface. Middle Neopleistocene. Khazar Horizon / Lower Subhorizon. Alternation of grey clayish sand and grey clay (thickness is 62 m). Singil Beds. Grey clay with lenses of ashes in the upper part (thickness is 8.3 m). Upper Neopleistocene. Khazar Horizon / Upper Subhorizon. Greyish-brown clay laminated with silty layers (thickness is 8.3 m). Erosional surface. Grey sand (thickness is up to 3 m). Alternation of brownish clay, loam, and grey sand or salts (thickness is up to 1 m). Erosional surface. Khvalyn Horizon / Lower Subhorizon. Grey subhorizontal sand (thickness is up to 0.5 m). Upper Subhorizon. Dark brown sand, loamy sand, and loam with horizontal and weak cross bedded layers (thickness is up to 23 m). Holocene. Brownish-grey sandy loam with traces of pedogenesis and carbonates (modern soil) (thickness is 0.2 m). 2. Paleomagnetic investigations The upper part of the section shows normal polarity and is correlated with the Brunhes Chron; the lower part is characterized by reverse polarity and is correlated with the Matuyama Chron. Each of the chrons has additional sub- and microzones of opposite polarity. The Brunhes-Matuyama boundary is located in the lower part of the Tyurkyan deposits at a level of -133 meters. Microzones n1RNPtr and n2RNPtr are located in the lower part of the Tyurkyan deposits and in the upper part of the RMatuyama epoch with thicknesses of 1 meter each. They possibly match the Kamikatsura excursion/Subchron. Twinned microzones r 1NNPtr – r2NNPtr located in the lower part of the normal polarity zone N-Brunhes possibly could be correlated with microzone Elunino VIII of the Russian General Magnetic Scale and could be its match in the summary sequence of the Fore-Caspian (Bogachkin et al., 2005). Microzones r3NNPtr, rn1NNPb, and rn2NNPb in Baku deposits possibly can be correlated with microzones Elunino VII-V. The Lower Khazarian subzone r 4NNPhz can be correlated with magnetozone Biwa II. The uncompleted interval with reverse polarity r 5NNPhz at the top of the paleomagnetic column could be correlated with the microzone Biwa I. 3. Palynological investigations New information on palynological data (dinocysts, algae, pollen, and spores) was obtained from the deposits of borehole 2 Kosika. Analysis of dinocysts and green algae permit us to subdivide the deposits into typical marine, fluvial, and estuarine facies. Eight pollen complexes were established in the palynological analysis. Arid stages were reconstructed in complexes 3 (interval 100-83 meters), 5 (63-46 meters), and 8 (7.9-5 meters). These spectra are characterized by increasing grass pollen (Artemisia, Apiaceae, Ephedra) and decreasing arboreal pollen. Steppe and semi-desert landscapes dominated during the accumulation of deposits during these intervals. During humid periods: complexes 1 (interval 141-132 meters), 2 (132-100 meters), 4 (83-63 meters), 6 (46-10.5 meters), and 7 (10.5-7.9 meters), the quantity of pollen from trees (Abies, Picea) and spores (Sphagnum, Lycopodium, Huperzia selago) increased. Marshes and wet areas with Betula sect. Fruticosae, and Sphagnum existed during the humid times. 3. Mollusks Nine malacological complexes were determined in the deposits of different origin. The most ancient complex was identified from the alluvial and subaerial deposits of the Tyurkyan Horizon. Mollusks are represented by freshwater species, which preferred water reservoirs with current; Cardiidae also existed. The second malacocomplex was found in deposits of marine origin that are correlated with the Baku Horizon. Mollusks are represented by the genus Didacna and poorly preserved shells of Cardiidae. Some brackish water gastropods were found. The third malacocomplex was found in alluvial-marine deposits that are correlated with the Lower Khazar Subhorizon. This complex is characterized by mixed freshwater and brackish water species. The fourth malacocomplex was found in lacus198


trine-liman dark grey clay of the Singil Horizon and is characterized by mainly freshwater species and some brackish water mollusks. The fifth complex coincides with liman and marine deposits of the Upper Khazar Subhorizon. Mollusks are represented by marine and brackish water species. The sixth malacocomplex was found in the alluvial-marine deposits of the Upper Khazar Subhorizon. Mollusks are not numerous and are represented by brackish water species. The seventh complex occurs in alluvial deposits with cross bedding of the Upper Khazar and are represented by numerous brackish water and freshwater species. Some terrestrial species exist in this complex. The eighth complex was found in the marine Lower Khvalyn deposits and contains marine species. The ninth complex exists in the Upper Khvalyn deltaic (?) deposits and is represented mainly by fragments of freshwater and marine shells. 4. Mammals Large mammal remains were found within the Kosika 2 section. The most significant finds of Bison priscus skeletons (2009) in situ originated from the upper part of the dark grey clay (Singil) at the base of the cliff. One of these skeletons is exhibited in the Astrakhan local natural history museum. Narrow symphysis, elongated diastema, low height of the horizontal branch of the lower jaw, and steeply upturned and strongly deflected beyond the plane of the occipital horn cores prove that bisons were of the forest-steppe type. The general length and curvature of the horn cores permit us to determine that these animals were a longhorn form of bison. Remains of Mammuthus sp. (femur and thoracic vertebra) and Rhinocerotidae gen. (carpal bone) are also known from the Singil clay. A Mammuthus sp. thoracic vertebra was found in the Khvalyn sand with Didacna protracta. Bone remains of Bison priscus, Mammuthus sp., and Equus sp. were collected from the surface of the Singil clay after flooding. There are no gnaw marks of large carnivores on the surface of the fossil bones. Small mammals from the Upper Khosarian deposits of Kosika include the typical Khosarian assemblage with Arvicola, Lagurini, Ellobius, and Spermophilus. Conclusion Preliminary results of our study permit us to reconstruct the paleoecological environment during the Neopleistocene in the surroundings of the Kosika locality. Tyurkyan time was a period of regression of the Apsheronian Sea. Lithology and texture of the deposits are of continental origin and prove the existence of rivers and freshwater lakes inhabited by freshwater mollusks. It was a humid period. The Baku transgression eroded the surface of the underlying deposits. Marine mollusks existed in this sea. At the beginning, it was arid, and later, a humid period. The Early Khazar is characterized by several changes to the fluvial and marine environment and several changes in humidity: at the beginning it was humid, later it was arid, and humid again at the end of this period. These changes in humidity and environment are proven by floral and malacological data. The Singilian period correlates to the regression of the Early Khazarian Sea, when freshwater and brackish water lakes and rivers existed. Large mammals inhabited flat areas and during watering some of them were caught by the bogs. This period was humid but colder than the modern one. During Late Khazar time, a new transgression began, and we can see its spreading by tracing marine deposits with specific mollusk species. At the end of this period, the sea again retreated, and rivers started to flow towards the receding seacoast. The existence of river beds which cut the underlying Upper Khazarian deposits attest to our reconstructions. These rivers had a floodplain where loamy and sandy deposits accumulated during flooding. At the end of this period, a new aridization began, and we can see shallow lakes where sulfide salts accumulated. At the early beginning of the Khvalyn period, a new transgression started, and we see here typical mollusk species that inhabited a shallow littoral. The thickness of these deposits is low because of the changes of the base of erosion during the retreat of the Early Khvalynian sea. At the studied area, we have interesting geological bodies which represent the underwater delta of the Pre-Volga and which nearly completely eroded the underlying marine deposits. During the Holocene, the modern Volga valley formed and changes in its development are represented in the river terraces, and high and low floodplains. Modern sandy soil formed at the interfluves . In the area west of the Kosika locality, eolian processes started because of weathering of the Khvalynian

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and Khazarian sands; moving sands began to develop, and they formed sand dunes and deflation depressions. Continuation of laboratory investigations on palynology, ostracoda, mollusks, and vertebrates will permit us to add more information to the paleocological reconstruction of the investigated territory in the near future. References Bogachkin, A.B., Grebenyuk, L.V., Grishanov, A.N., Fomin, V.A., Dyakina, A.V., Lavrizshev, V.A., and Krivko, L.F., 2005. Magnitostratigraphiia pleistotsenovykh otlozhenyi Prikaspiya [Magnetostratigraphy of the Pleistocene deposits of the Fore-Caspian region]. Nedra Povolzhya and Prikaspiya 42: 23-35. (In Russian) Sedaikin, V.M., 1988. Opornye razrezy chetvertichnykh otlozhenii Severo-Zapadnogo Prikaspiia [Reference Sections of the Quaternary Deposits of the Northwestern Pre-Caspian Region]. VINITY 1594-B-88, Moscow. (In Russian) Shkatova, V.K., 1973. Otchet po teme N 139 “Izuchenie opornykh razrezov chetvertychnykh otlozhenyi SSSR s tselyu razrabotky mestnykh stratigraphicheskyh skhem” [Report on theme No.139 “Study of the Key Sites of the Quaternary Deposits of the USSR for Development of the Local Stratigraphic Schemes”]. VSEGEI Press, Leningrad. (In Russian) Smagin, B.N., Troyanovskyi, S.V., Bushueva, V.P., Kuznetsova, V.I., and Shadrukhin, A.V., 1977. Otchet po kompleksnoi geologo-gidrologicheskoi i inzhenerno-geologicheskoi cyemke masshtaba 1:200000 listov L-38-XI, XII [Report on Integrated Geological-hydrogeological and Engineering-geological Mapping at the Scale 1:200,000, L-38-XI, XII]. Astrakhan Complexgeological Expedition NV TGU. Astrakhan Geological Survey Foundation, unpublished. (In Russian) Yanina, T.A., 2005. Didacny Ponto-Caspia [Didacna of the Ponto-Caspian Region]. Madgenta Press, Smolensk. (In Russian) Zhamoida, A.I., Girshgorn, L.C.H., Kovalevsky, O.P., Oleynikov, A.N., Prozorovskaya, E.L., Margulis, L.S., Khramov, A.N., and Shkatova, V.K., 2006. Stratigraficheskii Kodeks Rossii [Stratigraphic Code of Russia]. Third edition. Mezhvedomstvennyi stratigraficheskii komitet (MSK) Rossii. VSEGEI Press, St. Petersburg. (In Russian)

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