Wuzao Fm
Type Locality and Naming
Yan Chuntai named in 1932. The named section is located in Wuzao Village, Yiwu City, Zhejiang Province.
Synonym: Wuzao Gr. Original name of this formation is “Wuzao coal series”, it refers to a set of continental coal bearing clastic rock outcropping in the Jiangshan-Shaoxing Fault, which lies between the overlying coal-bearing continental clastic rock of the Upper Jurassic Majian Formation and the underlying old strata. In 1964, Chen Qishi restudied and revised the meaning of Wuzao coal series, and dated it as early Jurassic of Late Triassic, and renamed it Wuzao Group. In 1975, the Wuzao group was renamed the Wuzao Formation by the Regional Survey Team of Zhejiang and the Nanjing Institute of Geology and Paleontology, Chinese Academy of Sciences (1974), and dated in Late Triassic.
Lithology and Thickness
It is mainly composed of conglomerate, coarse sandstone, sandstone, mudstone with carbonaceous shale and coal bed, occasionally with littoral facies sand and mudstone.
Relationships and Distribution
Lower contact
This formation is in unconformable contact with underlying Chencai Gr quartz schist at the bottom with quartz feldspar coarse sandstone, gravel-bearing coarse sandstone. Schematic stratigraphic section indicates it is underlain by the Zhengtang Fm of earliest Triassic.
Upper contact
The overlying Jurassic Majian Fm is in disconformable contact at the top.
Regional extent
The lithology of this formation varies greatly, and it is distributed on the southeast side of the Jiangshan - Shaoxing Fault, extending from southeast to northeast. It is found sporadically in Daotangshan of Jiangshan County, Xiacheng of Zhuozhou city, Daoshiling, Wuzao of Yiwu City, Zhuji, Hetou Village, Sicheng County etc., the exposed thickness is 50 to 400 m.
GeoJSON
Fossils
Plants: Todites goepertianus, Cladophlebis haiburnensis, Dictyophyllum exile, Clathteris meniscioides, Pterophyllum ptilum, Cycladocarpidium erymani. Conchostracans: Euestheragenia minuta. Bivalves: Waagenoperna sp. etc.
Age
Depositional setting
Additional Information