Gongwusu Fm
Type Locality and Naming
The type section is in Youth farmland 6 km north of Gongwusu in Wuhai City, Inner Mongolia. The Gongwusu Fm was named by No.3 Team of Ministry of Geology and Mineral Resources in 1979, and was published by Chen Junyuan et al. (1984). Fu Lipu (1993) divided Gongwusu Fm of Chen et al. (1984) into two parts, and named the lower 33 m thick grayish green shale the Hermaori Fm (the present Lashizhong Fm), and the upper thin-bedded limestone the Gongwusu Fm.
Synonym: (公乌素组）
Lithology and Thickness
The formation is composed of alternative thin-bedded limestone, shale and sandstone of deep shelf environment (Fu et al., 1993). In the type area, the Gongwusu Fm recorded an incomplete thickness of 32 m.
Relationships and Distribution
Lower contact
It rests conformably on the green shale of the Lashizhong Fm
Upper contact
It is conformably overlain by the interbedding bioclastic limestone and shale of the Sheshan Fm
GeoJSON
Fossils
This stratigraphic unit yields graptolite of Amplexograptus gansuensis zone and, and is roughly equivalent to the Climacograptus wilsoni zone (Chen et al., 1984; Fu et al., 1993).
Age
Depositional setting
Deep shelf environment (Fu et al., 1993).
Additional Information