Elasmobranchs from the Lower Tertiary of the western Tarim Basin and their biostratigraphic significance

Li Guo-qing

pp. 107-136, in English

Abstract:

A regional elasmobranch fauna, the Tarim fish fauna, is examined in this paper. The composition of this fauna is comparable to a certain extent with the late Eocene eastern North Atlantic elasmobranch fauna of the Paris Basin. A comprehensive study of the stratigraphic distribution of the genera and species in the Tarim fish fauna indicates that the fish-bearing Wulagen Formation must include deposits formed mainly in the late Eocene and part of the lower Oligocene, and that the Qimugen Formation is basically early Eocene in age. An ecological explanation of this fish fauna suggests that a warm subtropical shallow Tarim Sea still existed by late Eocene and early Oligocene time. The paleozoogeographic interpretation of the taxa shared by both the Tarim fauna and the Paris Basin fauna also suggests that there might have been a wide communication between the Tarim Sea and the eastern part of the North Atlantic Ocean, or that the Tarim Sea was the east extension of the early eastern North Atlantic.

Keywords: Elasmobranch, fish, Lower Tertiary, biostratigraphy, Tarim Basin