Dang'en Fm
Type Locality and Naming
Named in 1977 by the third area survey team of Sichuan Geological Bureau. The type section is located in Dedagou, Dang'en Township, Batang County, Sichuan.
Synonym: Dangen Fm
Lithology and Thickness
It is a set of metamorphic rock series, which can be divided into three parts: Lower part is slate, phyllite intercalated with sandstone and marl, and basic volcanic rock and tuff conglomerate can be seen at the bottom, 716 m thick. Middle part is metamorphic sandstone It is intercalated with phyllite, 1001 m thick. Upper part is dominated by phyllite intercalated with metamorphic sandstone.
Relationships and Distribution
Lower contact
It is underlain by Upper Permian.
Upper contact
The top is in integrated contact with the overlying Liyi Gr
Regional extent
The lithology and thickness of this group vary greatly. The cashiers in Daocheng and Zedai are mainly composed of gray sandy slate intercalated with thin limestone, with a thickness of 580-684 m. In Daocheng Erze, it is a combination of limestone and dolomite. It is 211 m thick; in Muliwaneng, Qiongyi, Shuiluo and other places, it is mainly composed of volcanic rock, siliceous rock, and sand slate, with a thickness of 965-1687 m.
GeoJSON
Fossils
Contains bivalves in Daocheng Erze include Claraia sp., C. stachei, C. concentrica, Eumorphotis sp., E. multiformis, E. multiformis reticulata, E. m. rara, Pteria ussurica variabilisï¼›ammonoid fossils at Muliwaneng, Qiongyi, Shuiluo include Dieneroceras sp.; bivalves for example Claraia stachei, C. concentrica, C. hunanica, Pseudoclaraia wangi and conodont Parachirognathus sp., Pachycladina sp. etc.
Age
Depositional setting
This formation represents sub-deep-sea basin deposits in the areas of Daocheng Ruyatong and Zedai cashier, in the area of Daocheng Erze, it is a limited carbonate platform deposit, and in the Mulishuluo area, it is a deep-sea basin deposit (Li Yuankai et al., 1988).
Additional Information