Tarlang Fm
(7), late-Early and Middle Permian
Type Locality and Naming
The type section is located at the Taoshuyuan about 40 km to the northwest of the Daheyan Railway Station, Tulufan, Xinjiang. It was named by Xinjiang Petroleum Administration in 1973, and was cited officially by the Compiling Group for the Regional Stratigraphic Chart of the Xinjiang Uygur Autonomous Region in 1981.
Lithology and Thickness
Marl and Clastics. Lower part is composed of unequal interbeds of purple-grey and grey-green thin-bedded marl, conglomerate and sandstone Upper part is composed of dark-purple and yellow-green sandy siltstones, intercalated with conglomerate. Thickness is 411 m.
Relationships and Distribution
Lower contact
Conformable contact with the dark-grey conglomerate of the underlying Daheyan Fm
Upper contact
Conformable contact with the overlying Quanzijie Fm conglomerate
Regional extent
Distributed in the Yila Lake and the Korjie area in the western part of Xinjiang, as well as in the area to the west of the Danan Lake in the southeastern part of Keya Region of North Xinjiang.
GeoJSON
Fossils
Its lower part yields fish fossil represented by Turfania taoshuyuanensis; Ostracoda represented by Tomiella-Microdonta assemblage; bivalves represented by Anthraconauta-Mrasiella-Microdonta; plant fossils (phytolites) such as Callipteris altaica, Comia dentate, C. yichunensis and spore-pollen fossils.
Age
Depositional setting
It is interpreted as a lake-river-facies
Additional Information