Koumenzi Fm
Type Locality and Naming
The type section is located at the Tanggong village, about 10 km east of Koumenzi, Hami City, Xinjiang. It was named by by Liao Zhuoting et al. in 1990.
Lithology and Thickness
Siltstone and Clayey Limestone. Composed mainly of black-gray, green-gray and gray-white siltstone, carbonaceous slate, clayey siltstone, medium to coarse-grained sandstones, feldspar-rich sandstone and round conglomerate, intercalated with mudstone and clayey limestone lenses. It can be divided into three parts: Bottom portion consists of basal conglomerate (~300 m thick). Middle part, fine-grained clastic rock and mudstone, containing multiple layers of shells. Upper part, dominated by thin-bedded clayey limestone, occasionally intercalated with fine-grained clastic rock. Exposed thickness 2109 m.
Relationships and Distribution
Lower contact
Unknown: the bottom unexposed.
Upper contact
Unknown: in faulted contact with the overlying stratum.
Regional extent
In the Koumenzi and Dazigou areas on the south side of Moqinwula Mt.
GeoJSON
Fossils
Fossils mainly occur in the Middle calcareous siltstone interbeds and the Upper clayey limestone, including brachiopods Marginatia deruptus, Schuchertella magna, Dictyoclostus rostus, Unispirifer sp., Fusella sp., Ptychomaletoechia sp., Syringothyris sp., Megachonetes sp., etc.
Age
Depositional setting
It is interpreted as marine clastic and carbonate rocks
Additional Information