Discovery of Permian-Triassic Conodont Fauna in Tieshikou Area, Xinfeng, Jiangxi and Its Geological Significance

This paper for the first time reports and describes the Permian-Triassic conodont fauna from the series of Tieshikou Area, Xinfeng County, Jiangxi Province. Based on the study of conodonts, ammonoids, bivalves and brachiopods, Tieshikon series may be divided into 3 division, the Lower Part (beds 1-10), the Middle Part (beds 11-20) and the Upper Part (beds 21-23), they are equivalent to Early Triassic Griesbachian stage, Nammalian stage and Spathian stage respectively. The mixed-fauna with a coexistence of the Permian-type and Triassic-type fossils were discovered in bed's 2-8. The Permian-Triassic boundary may be placed temporarily at the clay rock (bed 1). The clay bed is yellow and white in color, only 3cm in thickness. The Latest Permian (Changhsingian) Neogondolella changxingensis-Neogondolella deflecta-Palaeofusulina assemblage was found below the clay bed. Anchignathodus cf. parvus-Towapteria scythica -Hollinella tingi-Crurithyris speciosa assemblage was found above the clay bed. The eon-tact between two systems is conformable. The discovery of Neospathodus homeri-N. tri-angularis conodont assemblage in Tieshikou area proves the existence of Spathian there.