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The Neoproterozoic–lower Cambrian in northern Govi-Altay, western Mongolia: regional setting, lithostratigraphy and biostratigraphy

Published online by Cambridge University Press:  01 May 2009

V. V. Khomentovsky
Affiliation:
United Institute of Geology, Geophysics and Mineralogy, Siberian Branch, Academy of Science, Novosibirsk, Russia
A. S. Gibsher
Affiliation:
United Institute of Geology, Geophysics and Mineralogy, Siberian Branch, Academy of Science, Novosibirsk, Russia

Abstract

This paper provides a framework for the stratigraphy and correlation of key sections through the Neoproterozoic–lower Cambrian of the Govi-Altay area, western Mongolia, studied by members of IGCP Project 303. Dzabkhan Formation volcanic rocks at the base of the succession are suggested to have formed during rifting of the Baydrik–Tarbagatay microcontinent in the Baykalian interval (c. 850–650 Ma). Pre-Vendian accretion transformed this rift and adjacent microcontinental fragments into a marginal marine back-arc basin, in which accumulated relatively uninterrupted Neoproterozoic and earliest Palaeozoic sediments. Lithostratigraphy for the latter is defined, with detailed maps, at five sections (Bayan Gol northern and southern blocks, Tsagaan Gol, Salaany Gol and Tayshir). The Tsagaan Oloom Formation lower member contains two diamictites of possible Sturtian age. Middle and upper carbonates are compared with the Yudomian (Vendian) of Siberia, the former ending with a unit of Boxonia grumulosa stromatolites. In the upper member, phosphorite-shale is followed mainly by limestones, with the earliest skeletal fauna. The Bayan Gol Formation comprises siliciclastic–limestone intercalations with increasingly diverse invertebrate biota. Correlation of lithological marker beds across the study area produces a composite stratigraphic section to which the earliest skeletal fossil occurrences are tied. The Anabarites trisulcatus Zone of the Nemakit-Daldynian Stage begins near the base of the Tsagaan Oloom Formation upper member (unit 11). The Purella antiqua Zone begins near the base of the Bayan Gol Formation (unit 18). Assemblages typical of the Nochoroicyathus sunnaginicus Zone (base of the Tommotian Stage) range through units 19 to 23. Elements typical of the Dokidocyathus regularis Zone (middle Tommotian) appear in unit 24 near the top of the Bayan Gol Formation.

Type
Articles
Copyright
Copyright © Cambridge University Press 1996

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References

Anonymous. 1974. Tectonics of the Mongolian People’s Republic. Moscow: Nauka, 282 pp.Google Scholar
Anonymous. 1978. Geology of Mongolian People’s Republic. Moskwa Izdatelstvo Nedra 1, (in Russian).Google Scholar
Arsent’ev, V. P. & Volkolakov, F. K., 1964. The Cambrian beds of the East Sayan. Geol. SSSR. Buryatskaya ASSR. XXV. Moscow: Chast’l. Izdatelstvo Nedra (in Russian).Google Scholar
Baikova, V. S. & Amelin, Yu. V., 1994. Sm—Nd age of Gashunnursky dyke complex (Mongolia). Doklady Akademii Nauk Rossii 334, 343–5 (in Russian).Google Scholar
Bezzubetsev, V. V., 1963. On the Precambrian—Cambrian stratigraphy of the Dzabkhan River Basin. Materials on the Geology of MPR. Gostopotekhizdat 1963, 2942 (in Russian).Google Scholar
Bowring, S. A., Grotzinger, J. P., Isachsen, C. E., Knoll, A. H., Pelechaty, S. & Kolosov, P., 1993. Calibrating Cambrian evolution. Science 261,1293–8.CrossRefGoogle ScholarPubMed
Brasier, M. D., Shields, G., Kuleshov, V. N. & Zhegallo, Le. A., 1996. Integrated chemo- and biostratigraphic calibration of early animal evolution: Neoproterozoic—early Cambrian of southwest Mongolia. Geological Magazine 133, 445–85.CrossRefGoogle Scholar
Buyakayte, M. J. & Kuz’michev, A. B., 1989. 718 million years: the Rb—Sr erochron of the Arkoi Series of Eastern Sayan. Doklady Akademii Nauk SSSR, 150–4 (in Russian).Google Scholar
Chumakov, N. M., 1993. The middle Siberian glaciohorizon of the Riphean. Stratigrafiya. Geologiya Korrelyatsiya 1, 2131 (in Russian).Google Scholar
Dorjnamjaa, D. & Bat-Ireedui, Ya., 1991. The Precambrian of Mongolia. Ulaanbaatar: Academy of Sciences of the Monglian People’s Republic, 182 pp.Google Scholar
Dorjnamjaa, D., Bat-Ireedui, Ya., Dashdavaa, Z. & Soelmaa, D., 1993. Guidebook for excursion: Precambrian—Cambrian Geology Khasagt-Khayrkhan Ridge, Gobi-Altay Province, Mongolia. Department of Earth Sciences, Oxford, 36 pp.Google Scholar
Endonzhamts, Zh. & Lkhasuren, B., 1988. Stratigraphy of the transitional beds between the Precambrian and Cambrian in the Zavkhan zone. Pozdniy Dokembriy i Ranniy Paleozoy Sibiri. Riphey i Vend. Izdatelstvo Instituta Geologii i Geofiziki, 150–62 (in Russian).Google Scholar
Gibsher, A. S., Bat-Ireedui, Y. A., Balakhonov, I. G. & Efremenko, D. E., 1991. The Bayan Gol reference section of the Vendian—Lower Cambrian in central Mongolia (subdivision and correlation). In Late Precambrian and Early Palaeozoic of Siberia. Siberian Platform and its framework (ed. Khomentovsky, V. V.), pp. 107–20. Novosibirsk: Ob’edinennyy Institut Geologii, Geofiziki i Mineralogii, Sibirskoe Otdelenie, Akademiya Nauk SSSR, 151 pp. (in Russian).Google Scholar
Gibsher, A. S., Izokh, A. E. & Khain, E. V., 1993. Geodynamic evolution of the Palaeo-Asian ocean in late Riphean—early Palaeozoic. In Fourth International Symposium on Geodynamic evolution of Palaeo-Asian ocean, pp. 67–9. IGCP Project 282 Report no. 4. Novosibirsk.Google Scholar
Gibsher, A. S. & Khomentovsky, V. V., 1990. The sections of the Tsagaan Oloom and Bayan Gol Formations of the Vendian— Lower Cambrian in the Zavkhan zone of Mongolia. In Pozdniy Dokembriy i Ranniy Paleozoy Sibiri. Voprosy Regional’noy Stratigraphii, pp. 7991. Novosibirsk: Izdatelstvo Instituta Geologii i Geoflziki (in Russian).Google Scholar
Gibsher, A. S. & Laburkina, A. R., 1996. Biostratigraphy of the transitional Vendian—Cambrian beds of Central Mongolia. Doklady Akademii Nauk Rossi (in Russian).Google Scholar
Gibsher, A. S. & Terleev, A. A., 1992. Stratigraphy of the Upper Precambrian and Lower Cambrian of South-Eastern Tuva and Northern Mongolia. Geologiya and Geofizika 11, 2634 (in Russian).Google Scholar
Goldring, R. & Jensen, S., 1996. Trace fossils and biofabrics at the Precambrian—Cambrian boundary interval in western Mongolia. Geological Magazine 133,403–15.CrossRefGoogle Scholar
Ilyin, A. V., 1982. Geological development of Southern Siberia and Mongolia in the late Precambrian—Cambrian. Moscow: Nauka, 116 pp. (in Russian).Google Scholar
Ilyin, A. V., 1990. Proterozoic supercontinent, its latest Precambrian rifting, breakup, dispersal into smaller continents, and subsidence of ttheir margins: Evidence from Asia. Geology 18, 1231–4.2.3.CO;2>CrossRefGoogle Scholar
Kargapolov, S. A., 1991. Metamorphism of the Mugur zonal complex (Sangilen, South-Eastern Tuva). Geologiya i Geofizika 3,109–19 (in Russian).Google Scholar
Keller, B. M. & Semikhatov, M. A., 1968. The reference section of the Riphean of continents. Itogi Nauki. Stratigrafiya. Moscow: Nauka 5108 (in Russian).Google Scholar
Kepezhinskas, P. K., Kepezhinskas, K. B. & Pukhtel’, I. S., 1991. Sm—Nd age of oceanic ophiolite of the Bayan-Khangor zone (Mongolian People—s Republic). Doklady Akademii Nauk SSR 315,718–21 (in Russian).Google Scholar
Khomentovsky, V. V., 1976. Vendian. Novosibirsk: Nauka, 272 pp. (in Russian).Google Scholar
Khomentovsky, V. V., 1986. The Vendian System of Siberia and a standard stratigraphic scale. Geological Magazine 123, 333–48.CrossRefGoogle Scholar
Khomentovsky, V. V., 1990 a. The Baykalian — a principal stage of history in the geological evolution of Siberia. In Geologiya i Geokhimika Dokembriya Sibirskoy Platformy i ee Skladchatogo Obramleniya, pp. 222–37. Leningrad: Nauka (in Russian).Google Scholar
Khomentovsky, V. V., 1996. The Sinian system of China and its analogues in Siberia. Geologiya i Geofizika no. 8, 100–20 (in Russian).Google Scholar
Khomentovsky, V. V., 1990 b. Vendian of the Siberian platform. In The Vendian System. Vol. 2. Regional Geology, pp. 2183. Berlin: Springer-Verlag.Google Scholar
Khomentovsky, V. V. & Karlova, G. A., 1992. Lower boundary of Cambrian and principles of its justification in Siberia. Geologiya i Geofizika 11,326 (in Russian).Google Scholar
Khomentovsky, V. V. & Karlova, G. A., 1993. Biostratigraphy of the Vendian—Cambrian beds and the lower Cambrian boundary in Siberia. Geological Magazine 130, 2945.CrossRefGoogle Scholar
Khomentovsky, V. V., Shenfil, V. Yu. & Yakshin, M. S., 1985. Riphean of Siberia. Geologiya i Geofizika 7, 2533 (in Russian).Google Scholar
Khomentovsky, V. V. & Others. 1978. Geological construction of the Mana trough and its position in Sayan-Altay “Baykalids”. Novosibirsk: Nauka, 223 pp. (in Russian).Google Scholar
Konnikov, E. G., Gibsher, A. S., Izokh, A. E. & Khain, E. V., 1994. Late Proterozoic evolution of the palaeo-Asian ocean north segment: new radiometrical, geological and geochemical data. Geologiya i Geofizika (in press, in Russian).Google Scholar
Korobov, M. H., 1980. Biostratigraphy of miomeran trilobites of the Mongolian Lower Cambrian. Biostratigrafiya niznego kembriya i Karbona Mongolii, pp. 5108. Moscow: Nauka (in Russian).Google Scholar
Korobov, M. N. & Missarzhevsky, V. V., 1977. On the Cambrian and Precambrian boundary layers of west Mongolia. Palaeozoic Invertebrates of Mongolia. Transactions of the Joint Soviet—Mongolian Palaeontological Expedition 5, 79 (in Russian).Google Scholar
Landing, E., 1994. Precambrian—Cambrian boundary global stratotype ratified and a new perspective of Cambrian time. Geology. 22,179–81.2.3.CO;2>CrossRefGoogle Scholar
Lebedev, V. I. & Others. 1991. U—Rb age of high-temperature metamorphism and ultrametamorphism of Sangilen (south-eastern Tuva). Doklady Akademii Nauk SSSR 320, 682–6 (in Russian).Google Scholar
Lesnov, F. P., 1993. Multistage formation of mafic—ultramafic plutonic complexes of ophiolite associations. Fourth International Symposium on Geodynamic evolution of Palaeo-Asian ocean, pp. 97–9. IGCP Project 282 Report no. 4. Novosibirsk.Google Scholar
Lindsay, J. F., Brasier, M. D., Dorjnamjaa, D., Goldring, R., Kruse, P. D. & Wood, R. A., 1996 a. Facies and sequence controls on the appearance of Cambrian biota in southwestern Mongolia: implications for Cambrian—Precambrian boundary. Geological Magazine 133, 417–28.CrossRefGoogle Scholar
Lindsay, J. F., Brasier, M. D., Shields, G., Khomentovsky, V. V. & Bat-Ireedui, Y. A., 1996 b. Glacial facies associations in a Neoproterozoic back-arc setting, Zavkhan Basin, western Mongolia. Geological Magazine 133, 391402.CrossRefGoogle Scholar
Markova, N. G., 1975. Stratigraphy of lower and middle Paleozoic of Western Mongolia. Moscow: Nauka, 120 pp. (in Russian).Google Scholar
Markova, N. G., Korobov, M. N., Zhuravleva, Z. A., 1972. On the question about the Vendian—Cambrian beds of South-Western Mongolia. Byulleten’ Moskovskogo Obshchestva Ispytateley Prirody, Otdel Geologicheskiy 47, 5770 (in Russian).Google Scholar
Missarzhevsky, V. V., 1989. Oldest skeletal fossils and stratigraphy of Precambrian and Cambrian boundary beds. Transactions of the Geological Institute of the USSR Academy of Sciences 4437. Moscow: Nauka (in Russian).Google Scholar
Mltrofanov, G. L., Arsent’ev, V. P. & Mordovskaya, V. T., 1978. Sayan—Baykalian folded belt. Dokembriy continentov. Skladchatye oblasti i molodye platformy vostochnoy Evropy i Asii, pp. 65110. Novosibirsk: Nauka (in Russian).Google Scholar
Mossakovsky, A. A., Ruzhentsev, S. V., Samygin, S. G. & Keraskova, T. N., 1993. The Central-Asian fold belt: geodynamic evolution and formation history. Geotektonika 6, 332 (in Russian).Google Scholar
Neymark, L. A. & Others. 1990. About Early Proterozoic—Late Riphean age of Olokitian complex rocks (Northern Pribaykal area) on the basis of zircon geochronology. Geologiya i Geochronologiya Dokembriya Sibirskoy Platformy i ee Obramleniya, pp. 206–22. Leningrad: Nauka (in Russian).Google Scholar
Plumb, K. A., 1991. New Precambrian time scale. Episodes 14, 139–40.CrossRefGoogle Scholar
Repina, L. N., Khomentovsky, V. V., Zhuravleva, I. T. & Rozanov, A. Yu., 1964. Biostratigraphy of the Lower Cambrian of the Sayan-Altay folded region. Moscow: Nauka, 365 pp. (in Russian).Google Scholar
Rozanov, A. Yu., 1992. Some problems concerning the Precambrian—Cambrian transition and Cambrian faunal radiation. Journal of the Geological Society, London 149, 593–8.CrossRefGoogle Scholar
Rozanov, A. Yu., Semikhatov, M. A., Sokolov, B. S., and others. 1997 (in press). Recent decision of the Precambrian—Cambrian boundary stratotype: breakthrough or misleading action. Stratigraphiya Geol. Korrelyatsiya 5, no. 1 (in Russian).Google Scholar
Semikhatov, M. A. & Serebryakov, S. N., 1967. The Vendian and Lower Cambrian of the Eastern Sayan south-eastern part. Izvestiya Akademii Nauk SSR. Seriya Geologicheskaya 4, 87102 (in Russian).Google Scholar
Semikhatov, M. A. & Others 1991. New stratigraphical scale of the USSR Precambrian. Izvestiya Akademii Nauk SSSR. Seriya Geologicheskaya 4, 316 (in Russian).Google Scholar
Şeng¨r, A. M. C, Natal’ln, B. A. & Burtman, V. S., 1993. Evolution of the Altaid tectonic collage and Palaeozoic crustal growth in Eurasia. Nature 364, 299307.CrossRefGoogle Scholar
Shafeev, A. A., 1970. Precambrian of South-Western Pribaykal and Khamar-Daban. Moscow: Nauka, 179 pp.Google Scholar
Shenfil, V. Yu., 1991. Late Precambrian of the Siberian platform. Novosibirsk: Nauka, 185 pp.Google Scholar
Val’kov, A. K., 1987. Biostratigraphy of lower Cambrian in east of Siberian Platform. Moscow: Nauka, 136 pp. (in Russian).Google Scholar
Voronin, Yu. I., Voronova, L. G., Grigor’eva, N. V., Drozdova, N. A., Zhegallo, E. A., Zhuravlev, A. Yu., Ragozina, A. L., Rozanov, A., Sayutina, T. A., Sysoev, V. A. & Fonin, V. D., 1982. The Precambran/Cambrian boundary in the geosynclinal areas (the reference section of Salaany-Gol, MPR). Trudy Sovmestnoy Sovetsoko-Mongol’skoy Paleontologicheskoy Ekspeditsii. Moscow: Akademia Nauk SSSR 18, 150 pp. (in Russian).Google Scholar
Zhuravleva, Z. A., 1974. Age and correlation of the ancient deposits of North-Westem Mongolia. Izvestiya Akademii Nauk SSSR. Seriya Geologicheskaya 12, 147–54 (in Russian).Google Scholar
Zonenshayn, L. P., Kuz’min, M. I. & Natapov, L. M., 1990. The tectonics of lithospheric plates. Book I. Moscow: Nedra, 327 pp. (in Russian).Google Scholar