M. A. NAUMCHEVA (PIN RAS), V. K. GOLUBEV (PIN RAS; KFU, Kazan)

Ostracod assemblages from the Permian­-Triassic boundary interval of the Moscow Syneclise

Five ostracod assemblages were identified while studying the stratigraphically most complete Permian­-Triassic Boundary located in the southern and central Moscow Syneclise. Assemblage I is identified in the lower part of the ostracod Wjatkellina fragiloides – Suchonella typica assemblage zone (AZ), which corresponds to the lower part of the Nefyodovian Regional Stage, of the Vyatkian. Assemblage II is characterized by high taxonomic diversity and corresponds to the upper part of the Wjatkellina fragiloides – Suchonella typica AZ and the lower part of the Suchonellina perelubica – Suchonella rykovi – S. posttypica AZ. Its affinity with the Nefyodovian or Zhukovian regional stages remained unclear. Assemblage III is determined from the renewal of the taxonomic composition of associations and belongs to the upper part of the Suchonellina perelubica – Suchonella rykovi – S. posttypica AZ and the Zhukovian Regional Stage. Assemblage IV is identified from significant change in the taxonomic composition and the predominance of Darwinula and Gerdalia representatives in the associations. It is confined to the lower part of the Darwinula mera – Gerdalia AZ and the lower part of the Vokhmian Regional Stage. Assemblage V is characterized by a reduction in the abundance of Gerdalia and an increase in the diversity of Darwinula. It corresponds to the upper part of the Darwinula mera – Gerdalia AZ and the upper part of the Vokhmian Regional Stage.
Keywords: nonmarine ostracods, assemblages, Permian­-Triassic boundary, Moscow Syneclise.
Для цитирования: М. А. Наумчева, В. К. Голубев. Комплексы остракод пограничных отложений перми и триаса Московской синеклизы // Региональная геология и металлогения. – 2019. – № 80. – С. 21–29.