Sanshilidadun Fm
Type Locality and Naming
Turpan Basin. Xia Gongjun erected the Sanshilidadun bed in 1956. The section for the designation is at Sanshilidadun to the east of the Shanshan County, Xinjiang.
Lithology and Thickness
The Sanshilidadun Formation is represented by brown red, brown yellow and purple red sandstone and conglomerate with mudstone. The formation is 763 m thick. It decreases in thickness from west to east, ranging from 53 to 810 m.
Relationships and Distribution
Lower contact
The base of the formation marked by purple red thick-bedded conglomerate lies unconformably on the underlying Upper Jurassic Kalazha Fm.
Upper contact
The top of the formation marked by brown red and brown yellow sandstone lies conformably below the green bed of the overlying Shengjinkou Fm.
Regional extent
The present formation occurs in the Huoyanshan and Shanshan areas of the Turpan basin and is also distributed sporadically south of the line linking Qiketai, Sanjianfang, Liaodun and Sandaoling. It varies considerably in lithology, commonly with relatively thick gray green basal conglomerate. It becomes coarser in lithology from west to east; it is dominated by sandstone and sandy mudstone in the west and by conglomerate in the eastern part.
GeoJSON
Fossils
It yields ostracods Rhinocypris cirrita, etc.
Age
Depositional setting
It mainly belongs to lacustrine deposition.
Additional Information