Jiulongkou Fm
Type Locality and Naming
Bureau of Geology and Mineral Resources of Hebei Province (BGMRH(Hebei)P) (1996) proposed a lectostratotype, which is located at the Jiulongkou village (former site) (E114°15′, N36°25′), Xiazhuangdian town, Anyang City, Henan Province. It was formally and validly published by BGMRH(Hebei)P (1989). Pei et al. (1963) firstly used this name but they didn’t assign the type section. The reference “Pei et al. (1959) in ‘Sanmenxia Quaternary Geology Conference Proceedings’” cited by BGMRH(Hebei)P(1996) is a misquote
Synonym: According to Gao et al. (2014a), the Zhangwu Fm in Henan Province is a synonym of the Jiulongkou Fm in Hebei Province.
Lithology and Thickness
The Jiulongkou Fm is characterized by a series of purple claystones and sandy claystones interbedded with greyish-white or greyish-yellow sandstones or sandstones with gravels. Its bottom contains conglomerates. Its upper part contains marlstones. It contains mammalian fossils. Its thickness is in range of 30~70 m.
Relationships and Distribution
Lower contact
In the type section, the Jiulongkou Fm unconformably contacts with the underlying Upper Permian Shangshihezi Fm.
Upper contact
In the type section, the Jiulongkou Fm is overlain disconformably by upper Miocene grey conglomerates. Regionally, the next younger unit is the Hiliuhe Fm.
Regional extent
The formation is distributed to the area north of the Zhang River, such as Xingtai, Handan, and Shahe of Hebei Province, and also to the area west of Anyang and north of the Anyang River in Henan Province.
GeoJSON
Fossils
Mammals: Percrocuta hobeiensis, Sansanosmilus palmidens, Macrotherium cf. M. brevirostris, Dicerorhinus cixianensis, Dicerorhinus sp., Plesiaceratherium gracile, Chilotherium sp., Aceratheriinae gen. et sp. indet., Rhinocerotidae gen. et sp. indet., Stephanocemas sp., Dicrocerus sp., Palaeomeryx sp., Sinomioceros jiulongkouensis, S. robustus, S. stenocephalus. (Chen and Wu, 1976)
Age
Depositional setting
It is interpreted as a river-lake environment.
Additional Information