Zhumabao Fm
Type Locality and Naming
The Zhumabao Formation was erected by the Inner Mongolia Regional Geological Survey Team in 1973. The section for the designation is at Zhumabao about 41 km northwest of the Datong City of Shanxi. The reference section is from Xinyaogou to Hangeda about 4 km southeast of the Zuoyun County of Shanxi.
Synonym: Zhumapu Fm
Lithology and Thickness
The Zhumabao Formation is represented by grey white and yellow purple red sandy mudstone and siltstone with conglomerate, which is divided in ascending order into four members. First member is dominated by blackish purple red sandy mudstone with gray white gravel-bearing grit and small amounts of gray green mudstone. Second member is purple red sandy mudstone with gray green medium-bedded medium and fine-grained sandstone and gravel-bearing grit. Third member is purple red sandy mudstone interbedded with gray green or gray white sandstone. Fourth member is mainly dark purple red or bright red siltstone and sandy mudstone with gray white sandstone. The Zhumabao Formation is 720 m thick.
Relationships and Distribution
Lower contact
The base of the formation marked by dark purple red gravel-bearing sandy mudstone is separated from the underlying Zuoyun Fm marked by red mudstone and shows a disconformable contact with the latter.
Upper contact
The top is bounded by the appearance of dark purple red sandy mudstone lies unconformably under the overlying Neogene basalt.
Regional extent
The present formation is distributed in the Youyu, Zuoyun, Yanggao and Tianzhen Counties and the Datong City of Shanxi. In Wujiashan of the Tianzhen County, it shows an angular discordance on the Changcheng series. In Guayuan of Datong and in Jiniangcheng of Yanggao, it also shows an angular discordance on the Achaean Jining Group. (Yu Jingxian)
GeoJSON
Fossils
The formation yields Reptilia (including dinosaurs) Plisauridae indet., Velociraptor cf. mongoliensis, Microceratops cf. gobiensis, Bacthosaurus johnsoni, hadrosauroids Yunganglong and Zuoyunlong; Bivalves Pseudohyria gobiensis, P. tuberculata, Sphaerium shantungensis; ostracods the Cypridea-Candona- Talicypridea assemblage; Charophytes Aptopochara daitongensis, Aclistochara linxiensis, Amblyochara media; and floras Platanus cf. cuncijolia, Pagiophyllum sp.
Age
Depositional setting
It belongs to lacustrine deposition.
Additional Information