Chongan Fm
Type Locality and Naming
Western Fujian. Li Jianhai et al erected the Chongan Formation in 1994. The section for the designation is in the Huiwan Village 10 km southwest of the Wuyi City of Fujian. The Chongan Formation represents a group of purple red macroclastic rocks over the Shaxian Fm around the Wuyishan City, which has been assigned to Late Cretaceous. It is the third rock formation of the Chishi Gr.
Lithology and Thickness
The Chongan Formation is mainly represented by purple red thick-bedded and greatly thick-bedded sandy conglomerate, conglomerate with fine sandstone and siltstone, often forming Danxia geomorphology after weathering. Both are in conformably contact. It exceeds 2015.6 m in thickness.
Relationships and Distribution
Lower contact
Its base built up by purple red moderately thick-bedded sandy conglomerate is differentiated from the Shaxian Fm of gravel-bearing sandstone and siltstone. It lies conformably or disconformably on the underlying Shaxian Fm.
Upper contact
Its top is unknown.
Regional extent
The formation occurs in the Cretaceous red-bed basins to the west of the Zhenghe-Dapu fault of east Fujian. Its lithology is basically uniform and the thickness is considerably variable, generally from 381 to 2015 m, in the various basins.
GeoJSON
Fossils
None listed
Age
Depositional setting
It is of fluvial-lacustrine deposition
Additional Information