Keguqinshan Fm
Type Locality and Naming
The type section lies along Aqiale River, Jinghe County, Xinjiang. It was named by Wu Naiyuan in 1981, and formally cited in Regional Stratigraphic Scale of Xinjiang in 1981.
Lithology and Thickness
Conglomerate and Sandstone. Consisting of gray-brown conglomerate, sandy conglomerate, calcareous sandstone, fine-grained sandstone and siltstone intercalated with bioclastic limestone. Exposed thickness 329.8 m. At Shatebulag of Hanjiga Mt. and the Kezilekunguyi area, it is dominated by conglomerate, and the thickness reduced to 53.5−88.7 m. Keguqin Mt. it is composed of fine-grained clastic rocks intercalated with limestone and mudstone, containing organic fossils, belonging to a littoral-neritic sedimentation environment.
Relationships and Distribution
Lower contact
Unconformable contact with the underlying Dongtujinhe Fm
Upper contact
Uncertain: overlying stratum not seen. Dashed on chart below Taerdetao Fm (basal Permian unit)
Regional extent
Distributed at Keguqin Mt. and Hanjiga Mt., extending NW-SE.
GeoJSON
Fossils
Brachiopod Choristites sp.; Bivalves Edmodia sp., Myalina tianshanensis and Schizodus sp.; gastropod Ephemites sp.
Age
Depositional setting
It is interpreted as a littoral deposits for the coarse-grained clastics; whereas the fine-grained clastics intercalated with limestone at Keguqin Mt. belong to a littoral-neritic depositional environment.
Additional Information