Abstract
The Upper Paleozoic preflysch sedimentary rocks in the Türkstan-Alay ranges are combined in a common section with limestone of autochthon and synsedimentation carbonate nappes, thus forming the upper-most layers of the stratigraphic section of the latter. By their lithology, relatively small thickness, facies variability, and position at the boundary between carbonate and flysch-olistostrome sequences (in the autochthon), these rocks correspond to a certain extent to preflysch of the Urals and the Mediterranean Alpine Belt. This association of clayey, carbonate, and terrigenous rocks is strictly constrained in stratigraphy (the upper portion of the lower Moscovian substage and the lower portion of the upper Moscovian substage) and localization (the southern slopes of carbonate platforms). The formation of this rock association immediately predated the Late Paleozoic overthrusting and deposition of terrigenous flysch. In paleotectonic terms, preflysch is an indicator of the initial stage of tectonic and magmatic activation that led to the replacement of carbonate sedimentation with deposition of terrigenous and clayey sediments, coeval volcanism, and stratiform ore formation. The following sequence of events has been outlined in the Early and Middle Carboniferous: (1) thrusting of volcanic-sedimentary rocks filling troughs over the northern margins of carbonate platforms, (2) lateritic weathering and deposition of marine bauxite in the Bashkirian and early Moscovian, (3) repeated overthrusting and deposition of preflysch on southern slopes of platforms, (4) invasion of the frontal flysch trough from the south, (5) scouring of preflysch and the underlying limestone, and (6) formation of flysch-olistostrome sequences and tectonic and gravity nappes in the late Moscovian time. This interpretation takes into account the southward vergence of thrust sheets and nappes, the structure and localization of allochthonous fragments of marginal zones of carbonate platforms, and the pre-Bashkirian thrusting of volcanic and sedimentary rocks over the condensed pelagic deposits of the Shalan Group. It is suggested that bauxite and preflysch materials had the same source and were deposited in the Middle Carboniferous on the offshore carbonate shoals.
Similar content being viewed by others
References
V. I. Belousov, “On the Role of Olistostromes and Nappes in the Stratigraphy of Flysch-Olistostrome Complexes in Turkestan-Alai Region, South Tien Shan. Paper 1,” Izv. Vyssh. Uchebn. Zaved., Geol. Razved., No. 3, 9–21 (1997).
V. I. Belousov, “On the Role of Olistostromes and Nappes in the Stratigraphy of Flysch-Olistostrome Complexes in Turkestan-Alai Region, South Tien Shan. Paper 2,” Izv. Vyssh. Uchebn. Zaved., Geol. Razved., No. 6, 33–45 (1998).
V. I. Belousov, “Angular Unconformities in the Turkestan-Alai Region and Correlation of Geological Events in the Carboniferous,” Stratigr. Geol. Korrelyatsiya 8(5), 96–110 (2000) [Stratigr. Geol. Correlation 8 (5), 511–525 (2000)].
V. I. Belousov, “Ore-Clastic Olistostromes, Ore Clasts, and Allochthonous Antimony-Mercury Deposits in the Alay Range, South Tien Shan,” Litol. Polezn. Iskop. 37(3), 289–305 (2002) [Lithol. Miner. Resour. 37 (3), 251–265 (2002)].
V. I. Belousov and M. A. Beer, “Flysch-Olistostrome Rock Association in the Alay Range,” Izv. Vyssh. Uchebn. Zaved., Geol. Razved., No. 6, 3–13 (1989).
Yu. S. Biske, Paleozoic Structure and Evolution of the South Tien Shan (Leningrad State Univ., St. Petersburg, 1996) [in Russian].
Yu. S. Biske and G. S. Porshnyakov, “Geodynamic Evolution of Paleozoides in the South Tien Shan,” in Proceedings on Tectonics, Geodynamics, and Metallogeny of the Ural-Tien Shan Fold System (Ural Division, Acad. Sci. USSR, Sverdlovsk, 1989), pp. 15–16 [in Russian].
Yu. S. Biske, G. S. Porshnyakov, Yu. A. Talashmanov, and A. V. Yagovkin, “Geological Setting of Nappe Development in the South Tien Shan,” in Relationships between Geological Processes in the Paleozoic Foldbelts of Central Asia (Ilim, Frunze, 1981), pp. 249–260 [in Russian].
A. K. Bukharin, V. D. Brezhnev, I. A. Maslennikova, et al., Tectonics of the Western Tien Shan (Nauka, Moscow, 1989) [in Russian].
V. N. Weber, Geological Map of Central Asia. Map Sheet Isfara, Northern Half (ONTI-NKTP, Novosibirsk, 1934) [in Russian].
B. Ya. Vikhter and S. D. Sher, “History of Geological Evolution of the South Tien Shan Fold System,” Geotektonika 15(3), 72–84 (1980).
G. I. Vyalukhin, “Devonian Bauxite Formation of the Urals As a Product of Crustal Compression,” in Proceedings of Tectonics, Geodynamics, and Metallogeny of the Ural-Tien Shan Fold System (Ural Division, Acad. Sci. USSR, Sverdlovsk, 1989), pp. 118–120 [in Russian].
V. B. Goryanov, A. D. Miklukho-Maklai, G. S. Porshnyakov, and A. V. Yagovkin, “Paleozoic Stratigraphy of the South Fergana Antimony-Mercury Belt,” in Scientific Proceedings (SAIGIMS, Tashkent, 1961), Vol. 6, pp. 7–28 [in Russian].
A. V. Dzhenchuraeva, “On a Hiatus between the Lower and Middle Carboniferous in the Alay,” in Collection of Geological Papers (L’vov Univ., L’vov, 1973), pp. 172–174 [in Russian].
A. V. Dzhenchuraeva and B. V. Poyarkov, “The Middle Carboniferous Stratigraphy of the Northern Slopes of the Alay and the Turkestan Ridges,” Izv. Vyssh. Uchebn. Zaved., Geol. Razved., No. 7, 34–39 (1979).
S. E. Zubtsov, “Occurrence of the Middle Paleozoic Shalan Group in the Kadamdjai Ore Field, Southern Tien Shan,” Vestn. Leningr. Gos. Univ., Ser. 7., No. 3, 75–76 (1987).
S. A. Kurenkov, Tectonics of Ophiolitic Complexes in the South Tien Shan (Nauka, Moscow, 1983) [in Russian].
M. M. Kukhtikov, Tectonic Zoning and the Most Important Relationships in the Paleozoic Structure and Evolution of the Gissar-Alay (Donish, Dushanbe, 1968) [in Russian].
G. A. Mizens, Doctoral Dissertation in Geology and Mineralogy (Yekaterinburg, 1995).
A. D. Miklukho-Maklai and G. S. Porshnyakov, “Middle Carboniferous Stratigraphic Subdivisions in the Alay and the South Fergana,” Vestn. Leningr. Univ., Ser. Geol., No. 18, 5–18 (1961).
A. D. Miklukho-Maklai, N. N. Verzilin, B. E. Dmitruk, et al., “New Data on Geology and Origin of Bauxite Units in South Fergana,” in Origin of Bauxites (Nauka, Moscow, 1966), pp. 257–262 [in Russian].
I. K. Nachev, “The Upper Jurassic Pre-Flysch in Bulgaria,” in Proceedings of the 10th Congress of Carpathian-Balkan Geol. Assoc. (KBGA, Bratislava, 1973), pp. 123–131.
A. V. Peive, L. P. Zonenshain, A. L. Knipper, et al., Tectonics of Northern Eurasia (Explanatory Notes to Tectonic Map of Northern Eurasia on a Scale 1: 5000000) (Nauka, Moscow, 1980) [in Russian].
G. S. Porshnyakov, Hercynides of the Alay Range and Adjacent Regions of the South Tien Shan (Leningrad State Univ., Leningrad, 1973), [in Russian].
G. S. Porshnyakov, V. L. Klishevich, V. I. Kotel’nikov, and A. V. Yagovkin, “Reduced Type of Middle Paleozoic Successions in the High Foothills of the Alay Range,” in Geology of Central Asia (Leningrad State Univ., Leningrad, 1961), pp. 73–81 [in Russian].
Ya. F. Porshnyakova, “New Evidence for the Namurian Sedimentary Rocks of the Alay Range: the Shalan Formation,” in Geology of Central Asia (Leningrad State Univ., Leningrad, 1961), pp. 194–207 [in Russian].
D. P. Rezvoi, Tectonics of the Turkestan-Alay Mountain System (Izd. L’vov Univ., L’vov, 1959) [in Russian].
R. Trümpy, “Tectonic Evolution of the Central and Western Alps,” in Tectonics of the Alpine Region (Mir, Moscow, 1965), pp. 9–121.
V. E. Khain, Regional Geotectonics. Pre-Alpine Asia and Australia (Nedra, Moscow, 1979) [in Russian].
V. E. Khain, Regional Geotectonics. Alpine Mediterranean Belt (Nedra, Moscow, 1984) [in Russian].
V. E. Khain, Tectonics of Continents and Oceans (2000) (Nauchnyi Mir, Moscow, 2001) [in Russian].
V. M. Tseisler, “Molasse Complexes and Orogenic Stages in Mobile Belts,” Izv. Vyssh. Uchebn. Zaved., Geol. Razved., No. 3, 3–9 (1997).
I. N. Cherenkov, Upper Paleozoic Flysch Formation in the Gissar-Alay (Donish, Dushanbe, 1973) [in Russian].
A. Codarcea, G. Raileanu, S. Nastaseanu, et al., “Aspects de sédimentation chaotique dans le Crétacé supérieur de l’autochtone des Carpates Méridionales,” in Proceedings of VII Congress of Carpathian-Balkan Geol. Association, Sofia, Sept. 1965 (1965), Reports, Part II, Vol. 1, pp. 265–273.
L. R. Contescu, “Preflisz I postflisz dwie syndiastroficzne formacie geosynclinalne,” in Pocznik polskiego towarzystwa Geologicznego (Krakow, 1968), Vol. 38, pp. 67–79.
I. Dvořák, “Mutual Relation of Pre-Flysch and Flysch Facies in the Moravian Paleozoic,” Vestnik Cheskcho Geol. Ustavu 67(5), 367–370 (1992).
F. Ebner, “Carboniferous Pre-Flysch Sediments in the Alpine Mediterranean Belts,” Mineralia Slovaca, No. 23, pp. 385–394 (1991).
H. Savu, S. Nastaseanu, M. Lupu, and I. Nicolae, “Ophiolites and Sedimentary Formations in South Apuseni and Southern Carpathians,” in Guidebook for the Field Works of the 2.1 and 2.2 Groups/1978 (Inst. Geol. Geophys., Bucharest, 1978).
Author information
Authors and Affiliations
Corresponding author
Additional information
Original Russian Text © V.I. Belousov, 2007, published in Geotektonika, 2007, No. 5, pp. 63–75.
Rights and permissions
About this article
Cite this article
Belousov, V.I. The Upper Paleozoic preflysch and overthrusting in the Türkstan-Alay ranges, southern Fergana. Geotecton. 41, 392–402 (2007). https://doi.org/10.1134/S0016852107050044
Received:
Issue Date:
DOI: https://doi.org/10.1134/S0016852107050044