Muerchang Fm
Type Locality and Naming
The Muerchang Fm is the lower-middle formation in the Pingyipu Gr. The type section is located at road side of Muerchang Village, Yunlong Township in Beichuan County, Sichuan Province. It was named by Hou Hongfei, Wan Zhengquan et al. in 1988.
Synonym: Mu'erchang Fm
Lithology and Thickness
Sandstone. It is dominated by light-gray to grayish-black thin- to thick-bedded quartz sandstone intercalated with clayey siltstone, fine-grained quartz greywacke, mudstone and sandy mudstone.
In Muerchang Village of Yunlong Township the formation can be divided into three members:
The lower, the Dishuiyan Member, is characterized by greywacke and mudstone.
The middle, the Gangou Member, is marked by mudstone, sandy mudstone and greywacke.
The upper, the Lingguanmiao Member, consists of greywacke and mudstone.
The formation is 883 m in total thickness
Relationships and Distribution
Lower contact
It is in conformable contact with the underlying Guixi Fm
Upper contact
It is in conformable contact with the overlying Guanyinmiao Fm
Regional extent
It is mainly developed in Pingwu and Beichuan counties.
GeoJSON
Fossils
In Muerchang Village of Yunlong Township the formation can be divided into three members:
The lower, the Dishuiyan Member, contains trace fossils, plant and Limulus fragments.
The middle, the Gangou Member, yields brachiopods Howellella, Strophochonetes pingyipuensis, ostracoda Guangxinia beichuanensis, Beyridia guixiensis and crinoid stems, bryozoans, etc.
The upper, the Lingguanmiao Member, bears trace fossils, plant and fish fragments, and ostracoda Ceratopsis giganta.
Age
Depositional setting
Coastal facies
Additional Information