geomorfГеоморфология и палеогеографияGeomorfologiya i Paleogeografiya2949-17892949-179710.31857/S0435428122030105geomorf-2503Research ArticleСедиментология, палеогеокриология, палеогидрологияSedimentology, palaeogeocryology, palaeohydrologyЛитолого-минералогическая характеристика нижнехвалынских шоколадных глин Нижней Волги (на примере разрезов Райгород и Средняя Ахтуба)Lithological-mineralogical characteristics of the Lower Khvalynian chocolate clays of the Lower Volga region (a case study of Raygorod and Srednyaya Akhtuba sections)МусаэлянР. Э.MusaelyanR. E.ЛебедеваМ. П.LebedevaM. P.РостовцеваЮ. В.RostovtsevaYu. V.ВарламовЕ. Б.VarlamovE. B.Почвенный институт имени В.В. ДокучаеваРоссияDokuchaev Soil Science InstituteRussian FederationМосковский государственный университет имени М.В. Ломоносова, геологический факультетРоссияLomonosov Moscow State University, Faculty of GeologyRussian Federation202205102022533Геоморфология96106Copyright © Мусаэлян Р.Э., Лебедева М.П., Ростовцева Ю.В., Варламов Е.Б., 20222022Мусаэлян Р.Э., Лебедева М.П., Ростовцева Ю.В., Варламов Е.Б.Musaelyan R.E., Lebedeva M.P., Rostovtseva Y.V., Varlamov E.B.Данная работа распространяется под лицензией Creative Commons Attribution 4.0.This work is licensed under a Creative Commons Attribution 4.0 License.https://geomorphology.igras.ru/jour/article/view/2503

Шоколадные глины – полифациальные морские отложения дискуссионного генезиса, широко распространенные в Нижнем Поволжье. Представлены результаты детального анализа особенностей микростроения, гранулометрических (42 образца) и минералогических (24 образца) составов разных слоев в толще нижнехвалынских шоколадных глин разрезов Средняя Ахтуба и Райгород. Разрезы расположены на противоположных сторонах Волго-Ахтубинской поймы. На основе данных, полученных с помощью лазерного дифрактометра, были рассчитаны литологические коэффициенты. Это позволило выделить семь общих для двух разрезов литотипов, каждый из которых также обладает особыми минералогическими и микроморфологическими характеристиками. Минералогические структурные особенности минералов во фракции <1 мкм в каждом литотипе и количественные соотношения глинистых минералов были определены методом рентгеновской дифрактометрии. Выявлено, что наиболее глинистые литотипы характеризуются преобладанием триоктаэдрического иллита над смектитом. Обратная ситуация наблюдается в алевритовых литотипах, где смектит преобладал над диоктаэдрическим иллитом. Набухающие компоненты были представлены высокозарядным бейделлитом в разрезе Средняя Ахтуба и высокозарядным монтмориллонитом в разрезе Райгород. Такие различия в соотношении и структуре глинистых минералов могут быть обусловлены разными источниками сноса или их различными синседиментационными или диагенетическими преобразованиями. Микроморфологические данные позволили установить биогенные текстуры в глинистых литотипах нижнехвалынских шоколадных глин. В алевритовых литотипах определены косая слоистость и углистое органическое вещество, что позволяет предполагать близость зоны их седиментации к береговой линии. Полученные материалы позволили показать сложный состав отдельных слоев толщи шоколадных глин и определить новые направления в изучении их генетических особенностей. Исследования отдельных литотипов нижнехвалынских шоколадных глин с детальной привязкой к глубинам проведены впервые.

Chocolate clays are polyfacial marine sediments of disputable genesis, widely distributed in the Lower Volga region. We present the results of detailed analysis of microstructure features, granulometric (42 samples) and mineralogical (24 samples) compositions of different layers in the thickness of the Lower Khvalynian chocolate clays of the Srednyaya Akhtuba and Raygorod sections. The sections are located on opposite sides of the Volga-Akhtuba floodplain. Based on the data obtained with a laser diffractometer, lithological coefficients were calculated. This allowed us to distinguish seven lithotypes common to the two sections, each of which also has specific mineralogical and micromorphological characteristics. The mineralogical structural features of minerals in the <1 μm fraction in each lithotype and the quantitative ratios of clay minerals were determined by X-ray diffractometry. It was revealed that the most clayey lithotypes are characterized by the predominance of trioctahedral illite over smectite. The opposite situation was observed in the silty lithotypes, where smectite predominated over dioctahedral illite. The swelling components were represented by highly charged beidellite in the Srednyaya Akhtuba section and highly charged montmorillonite in the Raygorod section. Such differences in the ratio and structure of clay minerals may be caused by different sources of drift or by their different synsedimentation or diagenetic transformations. Micromorphological data allowed us to establish biogenic textures in the clay lithotypes of the Lower Khvalynian Chocolate clays. In silty lithotypes, oblique layering and carbonaceous organic matter were determined, which suggests the proximity of their sedimentation zone to the coastline. The obtained materials made it possible to show the complex composition of individual layers of the chocolate clay sequence and determine new directions in the study of their genetic features. Studies of individual lithotypes of the Lower Khvalynian chocolate clays with a detailed reference to the depths were carried out for the first time.

литотипыглинистая минералогиялитологияколичественный анализмикроморфологияlithotypesclay mineralogylithologyquantitative analysismicromorphologyA.V. Yudina for help and consultation during granulometric sample preparation; Russian Science Foundation, projects No. 21-74-20121A.V. Yudina for help and consultation during granulometric sample preparation; Russian Science Foundation, projects No. 21-74-20121ReferencesArbuzova S.K. Mineralogicheskie osobennosti khvalynskikh glin v basseine Nizhnei Volgi (Mineralogical features of Khvalynsky clays in the Lower Volga basin). Byull. Komissii po izucheniyu chetvertichnogo perioda. 1970. No. 37. P. 41–46. (in Russ.)Arbuzova S.K. Mineralogicheskie osobennosti khvalynskikh glin v basseine Nizhnei Volgi (Mineralogical features of Khvalynsky clays in the Lower Volga basin). Byull. Komissii po izucheniyu chetvertichnogo perioda. 1970. No. 37. P. 41–46. (in Russ.)Arkhipov S.A. K litologo-facial’noi kharakteristike khvalynskikh shokoladnykh glin i usloviyam ikh obrazovaniya (To litologo-facial characteristic of the Khvalynian chocolate clays and to conditions of their accumulation). BCSQ. 1958. No. 22. P. 63–72. (in Russ.)Arkhipov S.A. K litologo-facial’noi kharakteristike khvalynskikh shokoladnykh glin i usloviyam ikh obrazovaniya (To litologo-facial characteristic of the Khvalynian chocolate clays and to conditions of their accumulation). BCSQ. 1958. No. 22. P. 63–72. (in Russ.)Badyukova E.N. Genezis khvalynskih (pleistotsen) shokoladnykh glin Severnogo Prikaspiya (Genesis of Khvalynian (Pleistocene) chocolate clay of Northern Caspian). Byull. MOIP. Otdel geologicheskii (Bull. MOIP Geology). 2000. Vol. 75. P. 25–34. (in Russ.) https://doi.org/10.31857/S0435428120030025Badyukova E.N. Genezis khvalynskih (pleistotsen) shokoladnykh glin Severnogo Prikaspiya (Genesis of Khvalynian (Pleistocene) chocolate clay of Northern Caspian). Byull. MOIP. Otdel geologicheskii (Bull. MOIP Geology). 2000. Vol. 75. P. 25–34. (in Russ.) https://doi.org/10.31857/S0435428120030025Biscaye R.E. Mineralogy and sedimentation of recent deep-sea clay in the Atlantic Ocean and adjacent Seas and Oceans. Bull. Geol. Soc. Am. 1965. Vol. 76. P. 803–832. https://doi.org/10.1130/0016-7606(1965)76[803:MASORD]2.0.CO;2Biscaye R.E. Mineralogy and sedimentation of recent deep-sea clay in the Atlantic Ocean and adjacent Seas and Oceans. Bull. Geol. Soc. Am. 1965. Vol. 76. P. 803–832. https://doi.org/10.1130/0016-7606(1965)76[803:MASORD]2.0.CO;2Gorbunov N.I. Vysokodispersnye mineraly i metody ikh izucheniya (Fine Minerals and Methods of Their Investigation). Moscow: Izdatel’stvo Akademii nauk SSSR (Publ.), 1963. 302 p. (in Russ.)Gorbunov N.I. Vysokodispersnye mineraly i metody ikh izucheniya (Fine Minerals and Methods of Their Investigation). Moscow: Izdatel’stvo Akademii nauk SSSR (Publ.), 1963. 302 p. (in Russ.)Goretskiy G.I. Formirovanie doliny Volgi v rannem i srednem antropogene (The Development of the Volga Valley During Early and Middle Anthropogene). Moscow: Nauka (Publ.), 1966. 412 p. (in Russ.)Goretskiy G.I. Formirovanie doliny Volgi v rannem i srednem antropogene (The Development of the Volga Valley During Early and Middle Anthropogene). Moscow: Nauka (Publ.), 1966. 412 p. (in Russ.)Greene-Kelly R. Identification of montmorillonoids. J. Soil. Sci. 1953. Vol. 4. No. 2. P. 223–227. https://doi.org/10.1111/j.1365-2389.1953.tb00657.xGreene-Kelly R. Identification of montmorillonoids. J. Soil. Sci. 1953. Vol. 4. No. 2. P. 223–227. https://doi.org/10.1111/j.1365-2389.1953.tb00657.xKurbanov R., Murray A., Thompson W., Svistunov M., Taratunina N., and Yanina T. First reliable chronology for the early Khvalynian Caspian Sea transgression in the Lower Volga River valley. Boreas. 2021. Vol. 50. P. 134–146. https://doi.org/10.1111/bor.12478Kurbanov R., Murray A., Thompson W., Svistunov M., Taratunina N., and Yanina T. First reliable chronology for the early Khvalynian Caspian Sea transgression in the Lower Volga River valley. Boreas. 2021. Vol. 50. P. 134–146. https://doi.org/10.1111/bor.12478Kvasov D.D. Pozdnechetvertichnaya istoriya krupnykh ozer i vnutrennikh morei Vostochnoi Evropy (Late Quaternary History of Large Lakes and Inland Seas in Eastern Europe), Leningrad: Nauka (Publ.), 1975. 279 p. (in Russ.)Kvasov D.D. Pozdnechetvertichnaya istoriya krupnykh ozer i vnutrennikh morei Vostochnoi Evropy (Late Quaternary History of Large Lakes and Inland Seas in Eastern Europe), Leningrad: Nauka (Publ.), 1975. 279 p. (in Russ.)Lavrushin Yu.A., Spiridonova E.A., Tudryn A., Chalié F., Antipov M.P., Kuralenko N.P., Kurina E.E. and Tucholka P. Kaspii: gidrologicheskie sobytiya pozdnego kvartera (The Caspian Sea: hydrological events of the Late Quaternary). Byull. Komissii po izucheniyu chetvertichnogo perioda. 2014. No. 73. P. 19–51. (in Russ.)Lavrushin Yu.A., Spiridonova E.A., Tudryn A., Chalié F., Antipov M.P., Kuralenko N.P., Kurina E.E. and Tucholka P. Kaspii: gidrologicheskie sobytiya pozdnego kvartera (The Caspian Sea: hydrological events of the Late Quaternary). Byull. Komissii po izucheniyu chetvertichnogo perioda. 2014. No. 73. P. 19–51. (in Russ.)Lebedeva M., Makeev A., Rusakov A., Romanis T., Yanina T., Kurbanov R., Kust P., and Varlamov E. Landscape Dynamics in the Caspian Lowlands since the Last Deglaciation reconstructed from the pedosedimentary sequence of Srednaya Akhtuba, Southern Russia. Geosciences. 2018. Vol. 8. P. 1–21. https://doi.org/10.3390/geosciences8120492Lebedeva M., Makeev A., Rusakov A., Romanis T., Yanina T., Kurbanov R., Kust P., and Varlamov E. Landscape Dynamics in the Caspian Lowlands since the Last Deglaciation reconstructed from the pedosedimentary sequence of Srednaya Akhtuba, Southern Russia. Geosciences. 2018. Vol. 8. P. 1–21. https://doi.org/10.3390/geosciences8120492Lebedeva M.P., Plotnikova O.O., Varlamov E.B., Churilin N.A., and Romanis T.V. Vliyanie sostava i svoistv khvalynskikh otlozhenii na evolyutsiyu pochv i pochvennogo pokrova volgo-ural’skogo mezhdurech’ya (po rezul’tatam mineralogo-mikromorfologicheskikh issledovanii) (Influence of the composition and properties of khvalynsk deposits on the evolution of soils and soil cover of the volga-ural interfluve (based on the results of mineralogical and micromorphological studies)). Mat-ly 2 nauch. konf. puti evolyutsionnoi geografii. Vol. 2. 2021. P. 527–530. (in Russ.) https://doi.org/10.3390/geosciences8120492Lebedeva M.P., Plotnikova O.O., Varlamov E.B., Churilin N.A., and Romanis T.V. Vliyanie sostava i svoistv khvalynskikh otlozhenii na evolyutsiyu pochv i pochvennogo pokrova volgo-ural’skogo mezhdurech’ya (po rezul’tatam mineralogo-mikromorfologicheskikh issledovanii) (Influence of the composition and properties of khvalynsk deposits on the evolution of soils and soil cover of the volga-ural interfluve (based on the results of mineralogical and micromorphological studies)). Mat-ly 2 nauch. konf. puti evolyutsionnoi geografii. Vol. 2. 2021. P. 527–530. (in Russ.) https://doi.org/10.3390/geosciences8120492Lokhin M.Yu. and Maev E.G. Pozdnepleistotsenovye del’ty na shel’fe severnoi chasti Srednego Kaspiya (Late Pleistocene Deltas on the Shelf of the Northern Part of the Middle Caspian). Vestn. Mosk. un-ta. Ser. 3. Geografiya, 1990. P. 37–45. (in Russ.)Lokhin M.Yu. and Maev E.G. Pozdnepleistotsenovye del’ty na shel’fe severnoi chasti Srednego Kaspiya (Late Pleistocene Deltas on the Shelf of the Northern Part of the Middle Caspian). Vestn. Mosk. un-ta. Ser. 3. Geografiya, 1990. P. 37–45. (in Russ.)Makshaev R.R. Paleogeografiya Srednego i Nizhnego Povolzh’ya v epokhu rannekhvalynskoi transgressii Kaspiya (Paleogeography of the Middle and Lower Volga Region in during the Caspian Early Khvalyn transgression). PhD Thesis. Moscow: MSU (Publ.), 2019. 160 p. (in Russ.)Makshaev R.R. Paleogeografiya Srednego i Nizhnego Povolzh’ya v epokhu rannekhvalynskoi transgressii Kaspiya (Paleogeography of the Middle and Lower Volga Region in during the Caspian Early Khvalyn transgression). PhD Thesis. Moscow: MSU (Publ.), 2019. 160 p. (in Russ.)Millot G. Geology of Clays (weathering, sedimentology, geochemistry). Leningrad: Nedra (Publ.), 1968. 360 p.Millot G. Geology of Clays (weathering, sedimentology, geochemistry). Leningrad: Nedra (Publ.), 1968. 360 p.Moskvitin A.I. Pleistotsen Nizhnego Povolzh’ya (Pleistocene of the Lower Volga region). Trudy Geol. Inst. Moscow: Nauka (Publ.), 1962. Vol. 64. 263 p. (in Russ.)Moskvitin A.I. Pleistotsen Nizhnego Povolzh’ya (Pleistocene of the Lower Volga region). Trudy Geol. Inst. Moscow: Nauka (Publ.), 1962. Vol. 64. 263 p. (in Russ.)Panin A., Astakhov V., Komatsu G., Lotsari E., Lang J., and Winsemann J. Middle and Late Quaternary glacial lake-outburst floods, drainage diversions and reorganization of fluvial systems in northwestern Eurasia. Earth-Sci. Rev. 2020. Vol. 201. No. 103069. https://doi.org/10.1016/j.earscirev.2019.103069Panin A., Astakhov V., Komatsu G., Lotsari E., Lang J., and Winsemann J. Middle and Late Quaternary glacial lake-outburst floods, drainage diversions and reorganization of fluvial systems in northwestern Eurasia. Earth-Sci. Rev. 2020. Vol. 201. No. 103069. https://doi.org/10.1016/j.earscirev.2019.103069Panin A.V., Sidorchuk A.Yu., and Ukraintsev V.Yu. The Contribution of Glacial Melt Water to Annual Runoff of River Volga in the Last Glacial Epoch. Water Resources. 2021. Vol. 48. No. 6. P. 877–885. https://doi.org/10.1134/S0097807821060142Panin A.V., Sidorchuk A.Yu., and Ukraintsev V.Yu. The Contribution of Glacial Melt Water to Annual Runoff of River Volga in the Last Glacial Epoch. Water Resources. 2021. Vol. 48. No. 6. P. 877–885. https://doi.org/10.1134/S0097807821060142Passega R. Texture as a characteristic of clastic deposition. AAPG Bulletin. 1957. Vol. 41. P. 1952–1984. https://doi.org/10.1306/0BDA594E-16BD-11D7-8645000102C1865DPassega R. Texture as a characteristic of clastic deposition. AAPG Bulletin. 1957. Vol. 41. P. 1952–1984. https://doi.org/10.1306/0BDA594E-16BD-11D7-8645000102C1865DPravoslavlev P.A. Materialy k poznaniyu nizhnevolzhskikh kaspiiskikh otlozhenii (Materials for the Knowledge of the Lower Volga Caspian Deposits). Warsaw: Univ. Press (Publ.), 1908. 467 p. (in Russ.)Pravoslavlev P.A. Materialy k poznaniyu nizhnevolzhskikh kaspiiskikh otlozhenii (Materials for the Knowledge of the Lower Volga Caspian Deposits). Warsaw: Univ. Press (Publ.), 1908. 467 p. (in Russ.)Priklonsky V., Gorkova I., and Oknina N. Inzhenerno-geologicheskie osobennosti khvalynskih glinistykh porod v svyazi s usloviyami ikh formirovaniya (Engineeringgeological properties of Khvalynian clays in the context of environments of their deposition). Trudy laboratorii gidrogeolicheskikh problem. 1956. Vol. 13. P. 1–152. (in Russ.)Priklonsky V., Gorkova I., and Oknina N. Inzhenerno-geologicheskie osobennosti khvalynskih glinistykh porod v svyazi s usloviyami ikh formirovaniya (Engineeringgeological properties of Khvalynian clays in the context of environments of their deposition). Trudy laboratorii gidrogeolicheskikh problem. 1956. Vol. 13. P. 1–152. (in Russ.)Rukhin L.B. Osnovy litologii (Basics of lithology). Leningrad: Nedra (Publ.), 1969. 703 p. (in Russ.)Rukhin L.B. Osnovy litologii (Basics of lithology). Leningrad: Nedra (Publ.), 1969. 703 p. (in Russ.)Rychagov G.I. Khvalynskii etap v istorii Kaspiiskogo moray (Khvalynian epoch in the history of the Caspian Sea). Vestn. Mosk. un-ta. Ser. 5. Geografiya. 2014. No. 4. P. 3–9. (in Russ.).Rychagov G.I. Khvalynskii etap v istorii Kaspiiskogo moray (Khvalynian epoch in the history of the Caspian Sea). Vestn. Mosk. un-ta. Ser. 5. Geografiya. 2014. No. 4. P. 3–9. (in Russ.).Sidorchuk A., Panin A., and Borisova O. Morphology of river channels and surface runoff in the Volga River basin (East European Plain) during the Late Glacial period. Geomorphology. 2009. Vol. 113. P.137–157. https://doi.org/10.1016/j.geomorph.2009.03.007Sidorchuk A., Panin A., and Borisova O. Morphology of river channels and surface runoff in the Volga River basin (East European Plain) during the Late Glacial period. Geomorphology. 2009. Vol. 113. P.137–157. https://doi.org/10.1016/j.geomorph.2009.03.007Svitoch A.A. O prirode khvalynskoi transgressii Kaspiya (About the nature of the Khvalynian transgression of the Caspian Sea). Okeanologiya. 2007. Vol. 47. No. 2. P. 304–311. (in Russ.).Svitoch A.A. O prirode khvalynskoi transgressii Kaspiya (About the nature of the Khvalynian transgression of the Caspian Sea). Okeanologiya. 2007. Vol. 47. No. 2. P. 304–311. (in Russ.).Svitoch A.A. and Makshaev R.R. “Shokoladnye” gliny Severnogo Prikaspiya: rasprostranenie, usloviya zaleganiya i stroenie (“Chocolate” clays of the Northern Caspian: distribution, occurrence, and structure). Geomorfologiya. 2015. No. 1. P. 101–112. (in Russ.) https://doi.org/10.15356/0435-4281-2015-1-101-112Svitoch A.A. and Makshaev R.R. “Shokoladnye” gliny Severnogo Prikaspiya: rasprostranenie, usloviya zaleganiya i stroenie (“Chocolate” clays of the Northern Caspian: distribution, occurrence, and structure). Geomorfologiya. 2015. No. 1. P. 101–112. (in Russ.) https://doi.org/10.15356/0435-4281-2015-1-101-112Svitoch A.A., Makshaev R.R., Rostovtseva Ju.V., Klyuvitkina T.S., Berezner O.S., Tregub T.F., and Homchenko D.S. Shokoladnye gliny Severnogo Prikaspiya (Chocolate clay of the Northern Caspian region). Moscow: Geograficheskiy fakul’tet MSU (Publ.), 2017. 140 p. (in Russ.)Svitoch A.A., Makshaev R.R., Rostovtseva Ju.V., Klyuvitkina T.S., Berezner O.S., Tregub T.F., and Homchenko D.S. Shokoladnye gliny Severnogo Prikaspiya (Chocolate clay of the Northern Caspian region). Moscow: Geograficheskiy fakul’tet MSU (Publ.), 2017. 140 p. (in Russ.)Svitoch A.A. and Yanina T.A. Chetvertichnye otlozheniya poberezhii Kaspiiskogo morya (Quaternary deposits of the Caspian sea coasts). Moscow: RASKhN (Publ.), 1997. 268 p. (in Russ.)Svitoch A.A. and Yanina T.A. Chetvertichnye otlozheniya poberezhii Kaspiiskogo morya (Quaternary deposits of the Caspian sea coasts). Moscow: RASKhN (Publ.), 1997. 268 p. (in Russ.)Toropov P.A. and Morozova P.A. Otsenka kolebanii urovnya Kaspiiskogo morya v epokhu pozdnepleistotsenovogo kriokhrona po rezul’tatam chislennogo modelirovaniya klimata (Evaluation of level variations of the Caspian Sea in the epoch of Late Pleistocene cryochrone by the results of numerical modeling of climate). Vestn. Mosk. un-ta. Ser. 5. Geografiya. 2011. No. 2. P. 55–61. (in Russ.) https://doi.org/10.31857/S0321059621060134Toropov P.A. and Morozova P.A. Otsenka kolebanii urovnya Kaspiiskogo morya v epokhu pozdnepleistotsenovogo kriokhrona po rezul’tatam chislennogo modelirovaniya klimata (Evaluation of level variations of the Caspian Sea in the epoch of Late Pleistocene cryochrone by the results of numerical modeling of climate). Vestn. Mosk. un-ta. Ser. 5. Geografiya. 2011. No. 2. P. 55–61. (in Russ.) https://doi.org/10.31857/S0321059621060134Varushchenko S.I., Varushchenko A.N., and Klige R.K. Izmenenie rezhima Kaspiiskogo morya i besstochnykh vodoemov v paleovremeni (Changes in the Regime of the Caspian Sea and Drainless Water Bodies in Paleotime). Moscow: Nauka (Publ.), 1987. 239 p. (in Russ.)Varushchenko S.I., Varushchenko A.N., and Klige R.K. Izmenenie rezhima Kaspiiskogo morya i besstochnykh vodoemov v paleovremeni (Changes in the Regime of the Caspian Sea and Drainless Water Bodies in Paleotime). Moscow: Nauka (Publ.), 1987. 239 p. (in Russ.)Weaver C.E. The effects and geologic significance of potassium “fixation” by expandable clay minerals derived from muscovite, biotite, chlorite, and volcanic material. American Mineralogist. 1958. Vol. 43. No. 9–10. P. 839–861. https://doi.org/10.1016/0016-7037(67)90060-9Weaver C.E. The effects and geologic significance of potassium “fixation” by expandable clay minerals derived from muscovite, biotite, chlorite, and volcanic material. American Mineralogist. 1958. Vol. 43. No. 9–10. P. 839–861. https://doi.org/10.1016/0016-7037(67)90060-9Yapaskurt O.V. Litologiya (Lithology). Moscow: Akademiya (Publ.), 2008. 336 p. (in Russ.)Yapaskurt O.V. Litologiya (Lithology). Moscow: Akademiya (Publ.), 2008. 336 p. (in Russ.)

The authors declare that there are no conflicts of interest present.