Guodikeng Fm
Type Locality and Naming
The type section is located at Quanzijie, Jimusar County, Xinjiang, while the reference section is situated at Dalongkou to the south of Santai Town, Jimusar County, Xinjiang. It was named by Tang Zhukui et al. in 1957, and was cited officially by the Institute of Geology under the Chinese Academy of Geological Sciences and the Scientific Research Institute of the Bureau of Geology and Mineral Resources of Xinjiang Uygur Autonomous Region (1990).
Lithology and Thickness
Siltstone. Its Lower part is composed of yellow-green, grey-brown and grey-black siltstones and silty siltstones, intercalated with brown clayey siltstone, calcareous siltstone, calcareous nodules and purple banded siltstone, lithic sandstone and clayey limestone nodules. Its Upper part is composed of purple silty siltstone. Thickness is 140 m.
Relationships and Distribution
Lower contact
Conformable contact with the underlying Wutonggou Fm.
Upper contact
Conformable contact with the overlying Jiucaiyuan Fm of the Lower Triassic Series.
Regional extent
Distributed in the vicinity of Urumqi City, and is extending easterly to Jimsar and southeasterly to the Tulufan Basin. In the area of Kanggur Pagoda till the Danan Lake to the southeast of the Shanshan County Town as well as in the vicinity of Kulai area to the northeast of Hami City it is the Kulai Fm that represents the late Permian strata.
GeoJSON
Fossils
The Lower and middle parts yielding the Darwinula-Panxiania-Suchonella-Darwinuloides assemblage of Ostracoda; Falsisca-Cornia-Cloiunguzites assemblage of Eosestheria; vertebrate fossils such as Jimusaria sinkianensis, Striodon magnus, Dicynodon tienshanensis; paleobotanic fossils represented by Zamiopteris-Viatscheslavia assemblage; spore-pollen fossils represented by Limatulasporites- Alisporites-Lueckisporites assemblage, megaspores represented by Triangulatisporites cf. triangulates-Narkisporites brevispinosus assemblage.
The Upper part of the formation yields vertebrate fossils, such as Lystrosaurus sp.; spore-pollen represented by Limatulasporites-Lundbladispora-Taeniaesporites assemblage; megaspore represented by the Triangulatisporites cf. triangulates- Trilites vulgaris assemblage; and Eosestheria fossils such as Falsisca sp., Cyclotunguzites sp., etc.
Age
Depositional setting
It is interpreted as a river-lake facies.
Additional Information