32 research outputs found
Inoceramid and foraminiferal record and biozonation of the Turonian and Coniacian (Upper Cretaceous) of the Mangyshlak Mts., western Kazakhstan
No full textThe Turonian and Coniacian (Upper Cretaceous) of the Mangyshlak Mts., western Kazakhstan, yielded a rich and relatively complete inoceramid bivalve record. The faunas and their succession correspond to those known from central and eastern Europe, allowing the zonation established in the latter areas to be applied in a virtually identical form. The gaps in the record of the group in Mangyshlak stem from the regional hiatuses in the geological record in the area and do not reflect any biogeographical differences between eastern and central-western Europe. Planktonic foraminifera are rare. Four successive interval range zones can be distinguished: in ascending stratigraphic order, the Helvetoglobotrunaca helvetica, Marginotruncaca pseudolinneiana, Marginotruncana coronata, and Concavotruncana concavata zones. Their correlation with the inoceramid zonation and, consequently, with the chronostratigraphic scheme, is demonstrated. The zonation and chronostratigraphic subdivision as applied in Mangyshlak may easily be applied to other areas of the peri-Caspian region (Caucasus, Tuarkyr, Kopet-Dagh, SE margin of the East-European Craton)
Inoceramid and foraminiferal record and biozonation of the Turonian and Coniacian (Upper Cretaceous) of the Mangyshlak Mts., western Kazakhstan
No full textThe Turonian and Coniacian (Upper Cretaceous) of the Mangyshlak Mts., western Kazakhstan, yielded a rich and relatively complete inoceramid bivalve record. The faunas and their succession correspond to those known from central and eastern Europe, allowing the zonation established in the latter areas to be applied in a virtually identical form. The gaps in the record of the group in Mangyshlak stem from the regional hiatuses in the geological record in the area and do not reflect any biogeographical differences between eastern and central-western Europe. Planktonic foraminifera are rare. Four successive interval range zones can be distinguished: in ascending stratigraphic order, the Helvetoglobotrunaca helvetica, Marginotruncaca pseudolinneiana, Marginotruncana coronata, and Concavotruncana concavata zones. Their correlation with the inoceramid zonation and, consequently, with the chronostratigraphic scheme, is demonstrated. The zonation and chronostratigraphic subdivision as applied in Mangyshlak may easily be applied to other areas of the peri-Caspian region (Caucasus, Tuarkyr, Kopet-Dagh, SE margin of the East-European Craton)
Radiolarians, foraminifers, and biostratigraphy of the Coniacian–Campanian deposits of the Alan-Kyr Section, Crimean Mountains
No full text
(Table 3) Chemical composition of Late Cenomanian - Early Turonian sedimentary rocks from the Mountainous Crimea and Northwest Caucasus
No full text(Table 1) Lithological-stratigraphic characteristics and CaCO3 and TOC contents in Late Cenomanian - Early Turonian sedimentary rocks from the Mountainous Crimea and Northwest Caucasus
No full text(Table 7) Enrichment factors of chemical components in Late Cenomanian - Early Turonian sedimentary rocks from the Mountainous Crimea and Northwest Caucasus relative to black shales
No full textComposition of sedimentary rocks from the Mountainous Crimea and the Northwestern Caucasus
No full textDetailed data obtained on chemistry of sedimentary rocks from the Mountainous Crimea and the Northwestern Caucasus that were dated at the Cenomanian/Turonian boundary and formed during Oceanic Anoxic Event 2 make it possible to calculate dissolved oxygen concentration in bottom waters of the sedimentation basin. Enrichment factors of trace elements in black shales are revised and an explanation is suggested for genesis of the rocks with regard for unusual climatic changes
