Paleogene Bivalve Communities in the western Tarim Basin and their paleoenvironmental implications

Lan Xiu

pp. 137-157, in English

Abstract:

According to their ecological characteristics, the Paleogene bivalves of the Bashibulake area can be divided into the following twelve communities: I. Brachidontes-Corbula Community; II. Pycnodonte (Pycnodonte) camelus-Eomeretrix suzakiensis Community; III. Ostrea (Ostrea) bellovacina-Panopea corrugata Community; IV. Flemingostrea-Panopea Community; V. Coubula-Solecurtus-Telline Community; VI. Ostrea (Turkostrea) afghanica-Sokolowia orientalis Community; VII. Ostrea (Turkostrea) strictiplicata-O. (T.) cizancourti Community; VIII. Sokolowia-Kokanostrea Community; IX. Ostrea (Ostrea) ulugqatica Community; X. Platygena-Pholadomya Community; XI. Ferganea-Lithophaga Community; XII. Cubitostrea-Ferganea swerzowii Community. A detailed analysis of the relationship between the succession of the Paleogene bivalve communities and their environmental changes and a discussion on the paleogeographical history of the western Tarim Basin have been given in the paper. These bivalve communities formed in different times indicate that there were at least three distinct transgressive-regressive cycles in western Tarim. During the Paleocene and Early Eocene, the transgression reached its greatest extension, and sea water reached as far as the southern margin of the Tarim Basin. At the end of the Oligocene the sea water completely retreated from the Tarim Basin and never returned.

Keywords: Tarim Basin, Paleogene, bivalve community, paleoenvironment