Lucaogou Fm
(6), mid-Early Permian
Type Locality and Naming
The type section is located at Cangfanggou of the West Yamalike Mt. (Yaomo Mt.) to the west of Urumqi City, Xinjiang. It was named by the Compiling Group for the Regional Stratigraphic Chart of the Xinjiang Uygur Autonomous Region in 1981.
Lithology and Thickness
Clastics and Limestone. It is divisible into two members as follows: The Lower member is composed of interbeds of grey-black, black-brown and black medium- and fine-grained sandstone, sandy shale and clayey shale, intercalated with dolomitic limestone and dolomite, with a thickness of 416 m. The Upper member is composed of interbeds of grey-black, brown-grey and black oil-shale and shale, intercalated with black thin-bedded bituminous shale and dolomitic limestone, with a thickness of 244 m. The formation is marked by the occurrence of oil shale. Source rock for Junggar Basin oil-gas fields.
Relationships and Distribution
Lower contact
Conformable contact with the underlying Jingjingzigou Fm
Upper contact
Conformable contact with the overlying Hongyanchi Fm
Regional extent
Distributed in the southern suburbs of Urumqi City, with its exposures being found extending eastward until the southeast of the Jimusar County.
GeoJSON
Fossils
Bivalves represented by Anthraconauta pseudophillipsis, A. iljinskiensis, Palaeanodonta glossitiformis, Mrassiella magniformis, Prokopievskia sp.; Ostracoda represented by the Tomiella-Permiana assemblage; vertebrate fossils represented by Turfania taoshuyuanensis, Tienshaniscus longipterus, Sinoniscus macrolepis, Urumqia luidawaaensis; Spore-pollen represented by Cordaitina-Hamiapollenites-Vittatina assemblage, and Plant fossils (phytolites) represented by Calamites sp., Cordaites borassifolia, etc.
Age
Depositional setting
It is interpreted as littoral lake-facies deposits.
Additional Information