Zhengtang Fm

Zhejiang Regional Stratigraphic Table Compilation Group was named in 1979. The named section is located in Zhengtang Yingwu Mountain, Jiangshan County, Zhejiang Province. The reference section is located in Dazipu, about 20 km southeast of Quzhou, Zhejiang. The Zhengtang Fm is a set of early Triassic clastic formations distributed from Jiangshan to Quzhou south of Zhejiang Province.

Synonym: Before the formation of the name, this stratum was called "Daye Limestone" by Liu Guochang et al. (1948). Later, due to the lack of fossil data, it was classified as "Lixian Coal Series".

It is dominated by fine clastic rocks. Lower part is calcareous siltstone, calcareous mudstone, and a small amount of dolomitic limestone. Upper part is mudstone, silty mudstone and siltstone. At the bottom, the calcareous siltstone is conformable with the underlying Upper Permian Dalong Fm of Upper Permian without peaking. Its thickness is 164 to 445 m.

Bivalves: Pseudoclaraia wangi, Claraia fukinensis, C. concentrica, C. annulata, C. griesbachi, C. stachei and Eumorphotis sp. Ammonoids: Ophiceras sp., ?Gyronites sp. And gastropods and brachiopods.