Affiliation:
1. Borisyak Paleontological Institute, Russian Academy of Sciences
2. Paleontological Institute, Mongolian Academy of Sciences
Abstract
The study of previously collected fossils and new materials on Cambrian mollusks from the Bayangol Formation of Western Mongolia (Zavkhan structural-facies zone) revealed a significant similarity in the taxonomic composition of the mollusk assemblages of Western Mongolia and Southern France (Heraultia Limestone, Marcou Formation, Montagne Noire). In addition to the previously reported four common species (Latouchella korobkovi (Vostokova, 1962), Protoconus orolgainicus (Zhegallo, 1996), Purella tenuis Zhegallo, 1996, and Watsonella crosbyi Grabau, 1900), we have identified 10 more common species for these regions: Auricullina auriculata (Vassiljeva, 1990), Bemella jacutica (Missarzhevsky, 1966), “Calbyella” multicostata Missarzhevsky, 1995, Cambroscutum concameratum Kerber, 1988, Helcionella sp., Merismoconcha tommotica (Zhegallo, 1996), Obtusoconus amplus (Zhegallo, 1982), Prosinuites tripartitus Kerber, 1988, Purella layracensis (Kerber, 1988), and Securiconus sp. We have to reconsider the existing reconstruction of faunal relations of paleobasins on the western frame of Gondwana in terms of substantiating a close faunal exchange with the Zavkhan terrane, which during the Early Cambrian was a part of microcontinents chain located at low latitudes between the Siberian Platform in the west and Gondwana in the east.
Publisher
The Russian Academy of Sciences
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