Xiaojiangbian Fm
(86, 87), Middle Permian
Type Locality and Naming
The type section is located in the Xiaojiangbian area 7 km to the south of the Anfu County Town, Ji’an City, Jiangxi Province, and the reference section is situated at the Xiaojiangbian, Anfu County Town, Ji’an City, Jiangxi Province. It was named by Wang Zhuquan in 1920.
Synonym: Hsiaokiangbian Fm
Lithology and Thickness
Claystone. Representing a suite of black calcareous shales, containing carbonaceous siltstone, intercalated with a small amount of thin-bedded marls and a great amount of limestone lenses, with a thickness of 285 m in the type section. The formation is stable in lithology, with a thickness of 34-285 m.
Relationships and Distribution
Lower contact
Conformable contact with the underlying Qixia Fm
Upper contact
Conformable contact with the overlying Wenbishan Fm, Mingshan Fm or Dangchong Fm.
Regional extent
Distributed in Jiangxi Province and South Hunan Province, with the thickest part of the formation being seen in the Xiaojiangbian area of the Anfu County, where its thickness is as great as of over 300 m; and with the thinner part of the formation being found in the Liling and Youxian areas.
GeoJSON
Fossils
In Jiangxi Province it yields abundant Brachiopods such as Orthotichia, Acosarina, Kiangsiella, Cathaysia, Haydenella, Echinoconchus, Dictyoclostoidea, Urushtenoidea, Neoplicatifera, etc., known as the Urushtenoidea chaoi-Haydenella chiianensis assemblage; Ammonoids such as Altudoceras, Paragastrioceras; and Fusulinids such as Chusenella, Parafusulina, etc.
Age
Depositional setting
It is interpreted as a restricted shallow-sea facies.
Additional Information