Caoliangyi Fm
Type Locality and Naming
The type section is located at Caoliangyi, ~20 km northeast of Fengxian County, Shaanxi; the reference section is at Caotangou (gully), Honghuapu, northwest of Caoliangyi. It was named by Zhao Yazeng and Huang Jiqing in 1931.
Lithology and Thickness
Sandstone and Coal. It is formed by a suite of coal-bearing clastic rocks. The Bottom is composed of conglomerate. Lower part consists of gray-white quartzose sandstone and conglomerate intercalated with siltstone, sandy mudstone and thin coal seams. Upper part is gray-white and light-gray sandstones, intercalated with shale, siltstone and coal seams. Total thickness over 342.4 m.
Relationships and Distribution
Lower contact
Uncertain -- the bottom is not completely exposed. Next older regional unit is the Eryuhe Fm
Upper contact
Uncertain -- the roof is not completely exposed.
Regional extent
Distributed in the areas from Tianshui of Gansu to Fengxian County, Taibai and Zhouzhi of Shaanxi.
GeoJSON
Fossils
This formation contains the Floral elements commonly found in the Visean Age: Archaeocalamites scrobiculatus, Sphenophyllum tenerrimum, Anisopteris petiolata, Diplothmema? Subgeniculata, and also flora of the Namurian and Westphalian ages: Rhodeopteridium parasparsa, Pecopteris aspera, Mesocalamites ramifer, Sphenopteris parabaeumleri, Linopteries neuropteroides, Neuropteris gigantea, etc.
Age
Depositional setting
It is interpreted as possibly sediments of the river-delta-swamp facies.
Additional Information