Bayingebi Fm
Type Locality and Naming
The Bayingebi Formation was erected by the Ningxia Regional Geological Survey Team in 1980. Its type section is at the Ura Mountain of Balong of Urad Houqi, Inner Mongolia (105°44′35″E; 40°58′N).
Lithology and Thickness
The lower part of the formation is represented by gray white and yellow brown conglomerate and calcareous feldspar fine sandstone with sandy conglomerate and shale; the middle part gray black silty limestone; and the upper part purple red, gray green, blue gray and gray black shale and oil shale with clayey siltstone. The Bayingebi Formation exceeds 654.9 m in thickness.
Relationships and Distribution
Lower contact
The base of the formation is unknown and may lies unconformably over the Upper Jurassic Shazaohe Fm.
Upper contact
The top is marked by gray green and purple gray shale and oil shale differentiated from and connected conformably with the overlying Suhongtu Fm.
Regional extent
The present formation is mainly distributed in the Suhongtu basin to the north of the Shalaza Mountain, the Uliji basin south of the Shalaza Mountain, and in the area west of Langshan in the northern part of the Alxa Zuoqi, the Inner Mongolia. In the Elesitai area, only the upper part of the formation is exposed, comprising gray black and gray green mudstone, shale interbedded with siltstone wint marl, measuring 447 m in thickness. In the Tabutaolegai area, the upper part is composed almost entirely of cryptocrystalline freshwater limestone and psammitic limestone. In the Hariaoribuge-Enbaotaolai area, the middle and upper parts of the formation contain a large amount of earth red mudstone, with a thickness generally ranging from 253 to 943 m, up to 1542 m at maximum.
GeoJSON
Fossils
The formation yields Fish Kunyangichthys, Anaethalion langshanensis; floras Brachyphyllum cf. obesum, Elatoclatdus sp., Sphenobaiera cf. longijolia, Baiera sp.; bivalves Corbicula liaomingensis, C.tetoriensis, Tetora cf. yokoyamai, Sphaerium cf.dayaense, S. cf. wiluicum and Ostracods Cypridea kansuensis, C.yabulaiesis, C.globra, limnocypridea grammi, Cypridea (Yumenia) suborijormis, etc. in Elesitai; Reptilia Psittacasaurus mongoliensis in Baogeqi; Esthrias Diestheria zoulangensis, Eosestheria sp. in Enbaotaolai; sporopollen represented by the Classopollis- Cicatricosisporites-Tricolpites assemblage; and also gastropods and insects.
Age
Depositional setting
It is of piedmont-shore-lacustrine facies.
Additional Information