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Permian and Triassic exotic limestone blocks of the Crimea Galina V. KOTLYAR All-Russian Geological Research Institute (VSEGEI), Sredny pr., 74, St. Petersburg, 199106 (Russia) [email protected] Aymon BAUD Musée de Géologie, BFSH2-UNIL, CH-1015, Lausanne (Switzerland) aymon.baud ©sst.unil.ch Galina P. PRONINA All-Russian Geological Research Institute (VSEGEI), Sredny pr., 74, St. Petersburg, 199106 (Russia) [email protected] Yuri D. ZAKHAROV Far East Geological Institute, Far East Branch of Russian Academy of Sciences, Pr. 100-letya, 159, Vladivostok-22, 690022 (Russia) [email protected] Valéry Ja. VUKS All-Russian Geological Research Institute (VSEGEI), Sredny pr., 74, St. Petersburg, 199106 (Russia) vsegei @ mail.wplus.net Merlynd K. NESTELL Department of Geology, University of Texas at Arlington, Arlington, TX 76019 (USA) [email protected] Galina V. BELYAEVA Far East Geological Institute, Far East Branch of Russian Academy of Sciences, Pr. 100-letya, 159, Vladivostok-22, 690022, (Russia) [email protected] Jean MARCOUX Sciences Physiques de la Terre, Université Paris VII, Tour 24/25, 1" étage, 2 Place Jussieu, F-75251 Paris cedex 05 (France) [email protected] GEODIVERSITAS • 1999 • '1 (3) 299 Kotlyar G. V., Baud A., Pronina G. P., Zakharov Y. D., Vuks V. Ja., Nestell M. K., Belyaeva G. V. & Marcoux J. Kotlyar G. V., Baud A., Pronina G. P., Zakharov Y. D., Vuks V. Ja., Nestell M. K., Belyaeva G. V. & Marcoux J. 1999. — Permian and Triassic exotic limestone blocks of the Crimea, in Crasquin-Soleau S. & De Wever P. (eds), Peri-Tethys: stratlgraphlc correlations 3, Geodiversitas 21 (3): 299-323. ABSTRACT Exotic limestone blocks of Permian and Triassic age occur in the Middle Triassic-Middle Jurassic Crimean olistostrome complex of the Marta and Alma River basins and in the Simferopol area. Rich assemblages of small foraminifers, fusulinids, brachiopods, rare ammonoids, and sphinctozoans KEYWORDS occur in these blocks. Fossils from Permian blocks indicate the presence of Upper Triassic, zonal assemblages for the Bolorian, Kubergandian, Murgabian, Midian, Rhaetian, Permian, Dzhulfian, and Dorashamian stages. The Neoschwagerina simplex fusulinid exotic blocks, zone is extended upward based on the presence in our material of Kuber Crimea, gandian ammonoids with Neoschwagerina simplex Ozawa. Comparison of the foraminifers, fusulinids, fauna from Triassic blocks to assemblages from other regions of the Tethys brachiopods, indicates that the age is Late Triassic Rhaetian corresponding to the ammonoids, sphinctozoans. Vandaites sturzenbaumi ammonoid zone. RÉSUMÉ Les blocs exotiques calcaires du Permien et du Trias en Crimée. Les blocs exotiques de calcaire permiens et triasiques de la Crimée appartien nent à l'unité olistostromale d'Eskiordin (Trias moyen-Jurassique moyen) et ont été trouvés dans les bassins-versant des rivières de Marta, d'Alma et dans la région du lac (réservoir) de Simferopol. Les blocs permiens contiennent des petits foraminiferes et des fusulines ainsi que des brachiopodes, de rares MOTS CLÉS ammonoïdes et des sphinctozoaires dont nous présentons l'inventaire. La dis Trias supérieur, Rhétien, tribution des assemblages fossilifères couvre la fin du Permien inférieur Permien, (Bolorien) ainsi que tout le Permien supérieur, du Kubergandien au blocs exotiques, Dorashamien. La présence conjointe d'ammonoïdes et de brachiopodes d'âge Crimée, foraminiferes, Kubergandien avec Neoschwagerina simplex Ozawa est signalée. L'analyse des fusulinides, micro- et macrofaunes des blocs triasiques ainsi que des comparaisons avec brachiopodes, les faunes semblables d'autres régions téthysiennes permettent d'attribuer aux ammonoïdes, sphinctozoaires. assemblages décrits un âge rhétien. INTRODUCTION ammonoids by Y. D. Zakharov, sphinctozoans by G. V. Belyaeva, and fusulinids by V. I. Davydov For this study, our team investigated Permian and M. K. Nestell. and Triassic exotic limestone blocks occurring at several localities in the area between Simferopol and the Marta River Basin. Limestone samples HISTORY containing remains of several different faunal groups were obtained. Carbonate microfacies Fokht (1901) studied the oldest deposits then were studied by A. Baud, small foraminifers by known from the Crimea. He named the G. P. Pronina (Permian and Triassic) and V. Ja. "Taurida Beds", and dated them as Late Triassic. Vuks (Triassic), brachiopods by G. V. Kotlyar, Moiseev (1939) named the Eskiorda Formation, 300 GEODIVERSITAS • 1999 • 21 (3) Permian and Triassic exotic blocks of the Crimea BLACK SEA A Simferopol area • Alma River Basin 9 Marta River Basin Cretaceous-Neogene deposits Bajocian intrusives Upper Jurassic deposits upthrown fault Eskiorda and Karadag Complex overthrust (Middle Triassic - Jurassic) Taurida flysch (Middle Triassic - Middle Jurassic) 0 8 km FIG. 1. — Sketch geological map of South Crimea (after Mlleev et al. 1989). a shallow-water conglomerate (Rhaetian-Liassic) where the Upper Triassic, Lower Taurida and the facies present in the northern part of the Kacha Liassic Upper Taurida (Eskiorda) formations uplift. Muratov (1949) divided the Taurida beds were proposed with two types of lithofacies for into three parts: (1) a lower unit of Late Triassic each unit. Koronovsky & Mileev (1974) conduc age; (2) a middle unit, the Eskiorda Formation; ted research on the Eskiorda Formation in the (3) an upper unit, both of early and middle Bodrak River Valley and proposed a broader Liassic age. Logvinenko et al. (1961) proposed a Carnian-Pleinsbachian stratigraphic range for it. more detailed subdivision of the Taurida Series On this basis, they increased the rank of this unit and considered the lower part to be of Early and to a Series and considered it as an equivalent of Middle Triassic age. the Taurida Series rock; they also stated, that the Study of outcrops in the valley of the right tribu Eskiorda Formation (or Series) in the Bodrak tary of the Bodrak River (Dagis & Shvanov River area represented a tectonic melange. 1965; Shvanov 1966) has shown that the Taurida Series rock ranges in age from Middle Triassic to Early Jurassic. The most common subdivision GEOLOGICAL SETTING (Fig. 1) scheme of the Taurida Series has been given in "Geology of the USSR" (Anonymous 1969), The oldest stratigraphic unit cropping out in the GEODIVERSITAC • 1999 • 21 (3) 301 Kotlyar G. V., Baud A., Pronina G. P., Zakharov Y. D., Vuks V. Ja., Nestell M. K., Belyaeva G. V. & Marcoux J. Crimean Mountains is the Taurida flysch of (1960, 1963), this unit has been recently map Middle Triassic to Toarcian age (Shalimov 1960, ped in detail and reinterpreted by Mileev et al. 1963). The underlying units and basement have (1989) as a composite and dismembered tectonic never been observed, but geophysical seismic complex. It is the best exposed within the data indicates a thin carbonate-clastic unit over Lozovaya shear zone of the Kacha uplift (nor lying granitic basement (Muratov et al. 1984). thern part of the core) and north of it, but it also The Taurida flysch is overlain with a structural occurs overthrust above the Taurida flysch in the unconformity either by Upper Jurassic deposits Bodrak and Marta River valleys. According to in the south and east of the Kacha uplift, or by the lithological and biostratigraphical contents, Lower Cretaceous deposits in the north and these authors subdivided the Eskiorda tectonic west. In some parts of the Kacha uplift, the complex into the Mender (Ladinian-Sine- Taurida flysch is allochthonously overlain by the murian), Dzhidair (Bajocian), Kichik (Norian), Eskiorda unit. The Taurida flysch makes up the Chenk (Middle-Upper Triassic?), Saraman (Late core of the Kacha uplift. Mileev et al. (1989) dis Triassic-Bajocian) and Bitak (Toarcian- tinguished the Alma unit for the proximal flysch Bathonian) subunits. The lithology consists in the core of the uplift, and the overlying Patil mainly of fine to coarse terrigenous elastics. The unit for the distal flysch. The Alma unit is expo turbiditic flysch sequence characterises the lower sed in the Belbek, Kacha, Marta, Alma, Salgir subunits and was probably deposited in shallow and Bodrak River valleys. It consists of predomi marine conditions because coal and coarse sand nantly gray, thin bedded fine sandstone and shale stone occurs in the upper Saraman subunit with reworked coalified plants debris. (Mileev et al. 1989). These authors regard the Commonly, the Alma unit is exposed only in Eskiorda complex as equivalent in age to the river valley floors; in the Bodrak River Valley it is Taurida unit. recorded in the middle and upper parts of slopes, Most of the exotic limestone blocks occur in the and there is overthrusting the Patil unit. In the Mender subunit and some in the Saraman sub- Alma River (Drovyanka Village and near unit. They are interpreted as olistholiths (olist- Partizanskoe Village) and Salgir River basins, the stromes for the older Carboniferous to Sine- Alma unit contains a Carnian and lower Norian murian part), and as tectonic incorporated fauna. Near Drovyanka Village (Alma River blocks (melange) for the younger Late Liassic- Basin), middle Liassic foraminifers occur in the Cretaceous part. Their origin is still controver shale. Near the mouth of the Marta River, sial. Some geologists believe that they originated Pliensbachian crinoids occur, and in the flysch of from the north (south of Scythian Plate margin), the Petropavlovsk quarry, bivalve mollusks of whereas others consider that they were transpor Toarcian-lower