Ivana Carevic

Upper Cretaceous volcanoclastic-sedimentary formations in the Timok Eruptive Area (eastern Serbia): new biostratigraphic data from planktonic foraminifera

Upper Cretaceous volcanoclastic-sedimentary formations in the Timok Eruptive Area (eastern Serbia): new biostratigraphic data from planktonic foraminifera The biostratigraphy of the Upper Cretaceous volcanoclastic-sedimentary formations cropping out in the Timok Eruptive Area of the eastern Serbian Carpatho-Balkanides is presented. Four lithostratigraphic units of formation rank are recognized in the Timok area: Stublica Clastics (Upper Albian/Cenomanian), Oštrelj (Lower Turonian/Santonian), Bor Clastics (Campanian/Maastrichtian) and Bukovo (Campanian/?Maastrichtian). Forty two species of planktonic foraminifera have been determined in the studied area. Eight planktonic foraminiferal zones of Middle Cenomanian through Middle Campanian age have been recognized. These are: Thalmanninella reicheli Interval Zone (Middle Cenomanian), Rotalipora cushmani Taxon Range Zone (Upper Cenomanian), Helvetoglobotruncana helvetica Taxon Range Zone (Lower Turonian), Marginotruncana sigali-Dicarinella primitiva Interval Zone (Upper Turonian to lowermost Coniacian), Dicarinella concavata Interval Zone (Lower Coniacian to lowermost Santonian), Dicarinella asymetrica Taxon Range Zone (Santonian), Globotruncanita elevata Interval Zone (Lower Campanian) and the Globotruncana ventricosa Interval Zone (Middle Campanian). The scarcity or lack of zonal species in the Lower Cenomanian and Upper Campanian/Maastrichtian strata prevents recognition of the nominal zones. The Upper Cretaceous planktonic foraminiferal zones from the Timok Eruptive Area are correlated with coeval zones from adjacent regions of Bulgaria and Romania and from other Tethyan regions.

Calpionellid biostratigraphy and microfacies of the Upper Tithonian pelagic carbonates in northeastern Serbia (Carpatho–Balkanides)

Abstract The occurrence of microfossil assemblage represented by calpionellids in close association with benthic foraminifera and encrusting Crescentiella morronensis is reported for the first time from the Upper Tithonian of NE Serbia. The biostratigraphic and sedimentological investigations were carried out on a 250 m thick carbonate succession in Jelenska Stena quarry cropping out along the Danube River Gorge in the border area of Serbian Carpatho–Balkanides and Romanian Southern Carphatians. On the basis of determined benthic foraminiferal taxa Textularia sp. cf. T. bettenstaedti and Everticyclammina praekelleri in the lower part of the succession and calpionellid association dominated by the representatives of calpionellid genera Tintinnopsella, Crassicollaria and Calpionella the carbonate succession is assigned to the Upper Tithonian. The scarcity of calpionellid zonal species prevents the nominal zones being recognized. Petrographic analysis of thin-sections led to the recognition of three basin microfacies types: bioclastic wackestone, bioclastic peloidal wackestone/packstone and mudstone. These microfacies characterize the SMF 3 and SMF 4 which indicate deposition in slope and toe-of-slope environments. This study extends the palaeogeographical distribution of Upper Tithonian calpionellids along the northern Tethyan margins. The investigated carbonate succession is compared with coeval strata from other northern Tethyan regions.