Baiyanghe Fm
Type Locality and Naming
Jiuquan Basin. This formation is completely exposed in the vicinity of Shiyougou in the Jiuquan basin, Gansu, so it was chosen as the naming section. Named the Baiyanghe Series by Sun Jianchu et al. in 1938 and renamed the Baiyanghe Formation by Yu Bailiang in 1952.
Lithology and Thickness
This formation consists dominantly of brick-red and light brownish red conglomeratic sandstone, sandstone and mudstone with sandy mudstone, marlstone and gypsum beds. The thickness varies from place to place, being generally <300 m in the Jiuquan basin and usually up to 1000 m on the southern margin of the Zhangye basin.
Relationships and Distribution
Lower contact
Disconformably overlies the Oligocene Huoshaogou Fm or the Mesozoic or older strata
Upper contact
The formation disconformably underlies the Pliocene Shulehe Fm (Jiuquan Basin); or perhaps disconformably under Hongya Fm (Hexi Corridor)
Regional extent
It is developed in the Jiuquan basin, Hexi Zoulang Nanshan, Heli Mountains and Tianjun Mountains.
GeoJSON
Fossils
It yields Amphechinus (Palaeoerinaceus) kansuensis, Desmatolagus pusillus (=D. shargaltensis=D.parvidens=Bohlinotona pusillus), Sinolagomys kansuensis, Tsaganomys altaicus, Yindirtemys grangeri (=Tataromys grangeri), Leptotataromys gracilidens, Parasminthus parvulus and Tachyoryctoides obrutschewi.
Age
Depositional setting
It is interpreted as Fluvio-lacustrine deposits.
Additional Information