Reference sections OF Cisuralian Series (Permian System): geochemical features

Object. Geochemical features of rocks from the Dal’ny Tulkas and Mechetlino sections located in the southern part of the West Urals foredeep are considered and are offered as International Standards for the global correlation (GSSP) of the lower boundaries of the Artinskian and Kungurian stages. Materials and methods. The content of rock-forming oxides and other components were studied for 15 and 20 samples of carbonate, clay and sandy rocks respectively in the sections of Dalnii Tyulkas and Mechetlino. The determination of the chemical composition of rocks was performed using a wave-dispersive X-ray fluorescence spectrometer S8 Tiger (Bruker, Germany). Results. The lithological characteristics of the sections, the content of oxides in mudstones and limestones of the boundary Sakmarian-Artinskian and of the boundary ArtinskianKungurian are taken. Mudstones of different stage are almost identical in average contents of the main components, whereas limestones have some differences. Correlative connections of oxides are analyzed and conclusions about mineral composition of rocks are made. Using the petrochemical modules and diagrams, it was established that the clay rocks in considered sections have mainly a hydromica composition. Based on the analysis of the indices of chemical weathering CIA, it is shown that the climate in the Cisuralian Epoch was predominantly arid. The tectonic environment of forming demolition sources, presumably corresponded to the active and passive margins of the continents. Conclusions. The main lithochemical characteristics of the rocks of the two sections under consideration are somewhat different, however, the boundaries of the stratigraphic subdivisions of each of them are virtually indistinguishable by lithochemical parameters, which may indicate the benefit of the continuity of sedimentation at the borders of centuries of the Cisuralian Epoch in this region. The conditions of sedimentation and the nature of eroded rocks in the area of demolition remained relatively constant. This is a positive point when looking the sections as International Standards for the global correlation (GSSP) reference objects – “golden nails”. 

1. Chernykh V.V., Chuvashov B.I., Davydov V.I., Henderson C.M., Shen S., Schmitz M.D., Sungatullina G.M., Sungatullin R.Kh., Barrick J.E., Shilovsky O.P. (2015) Southern Urals. Deep water successions of the Carboniferous and Permian. A Field Guidebook of XVIII International Congress on Carboniferous and Permian. Kazan, Academy of Sciences of Republic of Tatarstan Press. 88 p.

2. Chernykh V.V., Chuvashov B.I., Davydov V.I., Schmitz M.D. (2012) Mechetlino Section: A candidate for the Global Stratotype and Point (GSSP) of the Kungurian Stage (Cisuralian, Lower Permian). Permophiles, 56, 21-34.

3. Chuvashov B.I., Chernykh V.V. (2011) The Mechetlino section (South Ural): A potential limitotype of the Artinskian-Kungurian stage boundary. Dokl. Akad. Nauk, 441(5), 657-660. (In Russian)

4. Chuvashov B.I., Chernykh V.V., Shen S., Henderson C.M. (2013) Proposal for the Global Stratotype Section and Point (GSSP) for the base Artinskian Stage (Lower Permian). Permophiles, 58, 26-34.

5. Chuvashov B.I., Dyupina G.V., Mizens G.A., Chernykh V.V. (1990) Opornye razrezy verkhnego karbona i nizhnei permi zapadnogo sklona Urala i Priural’ya [Support sections of the Upper Carboniferous and Lower Permian of the Western Urals and the Cisuralian]. Sverdlovsk, UrO Akad. Nauk SSSR, 402 p. (In Russian)

6. Golovenok V.K. (1977) Vysokoglinozemistye formatsii dokembriya [High-Aluminous Precambrian Formations]. Leningrad, Nedra Publ., 140 p. (In Russian)

7. Harnois L. (1988) The CIW index: A new chemical index of weathering. Sediment. Geol., 55, 319-322.

8. Herron M.M. (1988) Geochemical Classification of Terrigenous Sands and Shales from Core or Log Data. J. Sediment. Petrol., 58, 820-829.

9. Interpretatsiya geokhimicheskikh dannykh [Interpretation of geochemical data]. (2001) (Ed. E.V. Sklyarov). Moscow, Intermet Engineering Publ., 288 p. (In Russian)

10. Kotlyar G., Sungatullina G., Sungatullin R. (2016) GSSPs for the Permian Cisuralian Series stages. Permophiles Newsletter of SCPS, 63, 32-37.

11. Maslov A.V., Mizens G.A., Badida L.V., Krupenin M.T., Vovna G.M., Kiselev V.I., RonkinYu.L. (2015) Litogeokhimiya terrigennykh assotsiatsii yuzhnykh vpadin Predural’skogo progiba [Lithogeochemistry of terrigenous associations of the southern basins of the Western Urals foredeep]. Ekaterinburg, IGG UrO RAN. 308 p. (In Russian)

12. Maynard J.B., Valloni R., Ho Shing Ju. (1982) Composition of modern deep-sea sands from arc-related basin. J. Geol. Soc. Amer. Spec. Publ., 10, 551-561.

13. Mizens G.A. (1997) Verkhnepaleozoiskii flish Zapadnogo Urala [Upper Paleozoic flysch of the Western Urals]. Ekaterinburg, IGG UrO RAN, 230 p. (In Russian)

14. Mizens G.A., Maslov A.V. (2014) Pelitic rocks from the molasse formation of the Southern Ural segment of the West Uralian foredeep: Lithogeochemistry, provenance composition, and paleotectonic reconstructions. Geokhimiya, 11, 1025-1042. (In Russian)

15. Mizens G.A., Maslov A.V. (2015) Sandstones from the molasse formation in the southern part of the Uralian foredeep. Litol. Polezn. Iskop., 5, 459-485. (In Russian)

16. Nesbitt H.W., Young G.M. (1982) Early Proterozoic climates and plate motions inferred from major element chemistry of lutites. Nature, 299, 715-717.

17. Roser B.D., Korsch R.J. (1986) Determination of tectonic setting of sandstone mudstone suite using SiO2 content and K2O/Na2O ratio. J. Geol., 94, 635-650.

18. Suttner L.J., Dutta P.K. (1986) Alluvial sandstone composition and paleoclimate, I. Framework mineralogy. J. Sediment. Petrol., 56, 329-345.

19. Tevelev Al.V., Tevelev Ark.V., Prudnikov I.A., Khotylev A.O., Baraboshkin E.E., Popov S.S. (2016) Structural parageneses of flysch complexes in the central part of the Uralian Foreland basin. Vestn. Moscow State Univers. Geol., 3, 11-16. (In Russian)

20. Turgeon S., Brumsack H.-J. (2006) Anoxic vs dysoxic events reflected in sediment geochemistry during the Cenomanian-Turonian Boundary Event (Cretaceous) in the Umbria-Marche basin of central Italy. Chem. Geol., 234, 321-339.

21. Yudovich Ya.E. (1981) Regional’naya geokhimiya osadochnykh tolshch [Regional geochemistry of sedimentary strata]. Leningrad, Nauka Publ., 276 p. (In Russian)

22. Yudovich Ya.E., Ketris M.P. (2000) Osnovy litokhimii [Fundamentals of lithochemistry]. St.Petersburg, Nauka Publ., 479 p. (In Russian)