Xihanshui Gr
Type Locality and Naming
The type section is located at the Leijiaba-Jiangkou of the upper reaches of Xihanshui River, south of Lixian, Gansu Province. It was named by Yeh Lianjun and Guan Shichong in 1944.
Lithology and Thickness
Sandy claystone. The Group is characterized by alternations of dark-gray slate, phyllite and calcareous sandstone, that are intercalated with some limestone beds in the middle and upper parts. The outcropping thickness is more than 8000 m. Comprises upward succession of Leijiaba Fm, Yuchiba Fm, Pingtou Fm, Longlinqiao Fm, and QiguDev Fm in one region; and upward succession of Wujiashan Fm, Qingshuigou Fm, Anjiacha Fm, Honglingshan Fm, and Shuanglanggou Fm in other region.
Relationships and Distribution
Lower contact
Not exposed; but maybe Silurian.
Upper contact
It is in faulted contact to Triassic on south side and to Carboniferous in its north side.
Regional extent
GeoJSON
Fossils
The limestone contains brachiopoda Stringocephalus sp. Spinatrypa sp.,
Coral Sinodisphyllum sp., Acanthophyllum sp., and conodonts.
A few spores and Antiarchi placoderm fish fossils occur in the lower part of the group.
Age
Depositional setting
Additional Information