Bianqinggou Fm
Type Locality and Naming
The type section is located at Bianqinggou of Shaotong county, Yunnan Province. It was named by Xian Siyuan and Zhou Xiyun in 1974, and formally quoted in 1978.
Lithology and Thickness
Mudstone. It is mainly composed of yellowish-green mudstone, sandy mudstone intercalated with thin-bedded limestone, and siltstone. The thickness of the Biangqinggou Fm is 77.9 m.
Relationships and Distribution
Lower contact
Conformable: The lower boundary is at the base of a 10-m bed of gray medium-bedded limestone, which differs from the brownish-yellow thick-bedded sandstone intercalated with yellowish-gray sandy mudstone of the underlying Pojiao Fm. They are in a conformable contact.
Upper contact
The upper boundary is marked by a change from yellow and yellowish-green mudstone to the thick-bedded quartz sandstone of overlying Suotoushan Fm.
Regional extent
The Biangqinggou Fm is mainly distributed in the Shaotong and Liliang area.
GeoJSON
Fossils
It yields abundant brachiopods Athyrisina yohi, Trigonospirifer trigonata, Nadiastrophia zhaotongensis, and coral Squameofavosites wagranensis.
Age
Depositional setting
It is interpreted as a platform deposition.
Additional Information