Shoushangou Fm
(20), lower to middle Kungurian Stage (late Cisuralian Epoch; late-Early Permian)
Type Locality and Naming
The type section is located at the Shihuiyao Quarry to the southeast of the Shoushangou Trench about 3 km to the east of the Yumuqiaozi Country, Huadian County, Jilin Province, and the reference section is situated in the East Hills of the Shoushangou Trench It was named by Ye Zhizheng in 1939, and was cited officially in the 7th Facicle on the Carboniferous System (1966) of the particular monograph "Stratigraphic Lexicon of China".
Lithology and Thickness
Limestone and Siltstone. Lower part is composed of grey-white thick-bedded limestone containing locally cherty concretions, intercalated with a small amount of grey-purple clayey limestone. Upper part is composed of grey clayey siltstone, yielding Fusulinids, corals and brachiopods. It has a thickness of over 343 m in the Shoushangou area, and of 1123 m already in the East Hills. The strata consist in ascending order of interbeds of thick-bedded crystalline limestone, clayey limestone, clayey sandstone, plate and sandstone, intercalated with acidic tuff and lenticular bodies of limestone with a varying thickness.
Relationships and Distribution
Lower contact
Disconformable. The formation is in most cases short of its top and base, and in the Houjiacao area it is probably in a disconformable contact with the underlying Shizuizi Fm due to the fact that in between them there occur a great amount of iron-manganese concretions, and they are in a concordant mode of occurrence as well.
Upper contact
Unconformable contact with the overlying Daheshen Fm
Regional extent
Distributed in the Yumuqiaozi till Changshan, Xiayuxing and Xinlitun areas of Huadian City, as well as in the southern part of the Shuangyang County.
GeoJSON
Fossils
In the area of the naming locality the formation yields Fusulinids represented by Parafusulina gruperaensis, P. splendens, Monodiexodina linearis, and Corals represented by Tachylasma. On the western flank of the naming locality the formation yields such Fusulinids as Schwagerina tschernyschewi; corals represented by the Wentzellophyllum-Cyathocarinia assemblage; and Brachiopods represented by Linoproductus, Dictyoclostus, Compressoproductus, etc.; belonging to the Luodianian Stage
Age
Depositional setting
It is interpreted as a shallow-sea clastic-rock and carbonate formation
Additional Information