Yazi Fm
(70), Kungurian Stage (late-Cisuralian Epoch; late-Early Permian)
Type Locality and Naming
The type section is located in the Yazi belt of the Wulipo area, Xikou region 25 km to the southeast of the Zhenan County, Shaanxi Province. It was named by Wang Guolian in 1973.
Lithology and Thickness
Limestone. Composed chiefly of grey-black and grey limestones, with a thickness of 172 m.
Relationships and Distribution
Lower contact
Conformable contact with the underlying Shimenya Fm
Upper contact
Conformable contact with the overlying Wulipo Fm
Regional extent
Distributed in the Xikou-Yundoutan area of the Zhenan County, Shaanxi Province, and also in the Yunxi County of Hubei Province, where it is 383 m thick. Same position as Qixia Fm in nearby regions.
GeoJSON
Fossils
In the Xikou region the Fusulinid fossils are divisible into two zones: The lower part is known as the Pamirina zone important members of which are the Pamirina pulchra, P. chinlingensis, Biwaella provecta, Toriyamaia provecta; the upper part is known as the Misellina zone important members of which are the Misellina claudiae, M. ovalis; in addition there occur also some coral fossils such as the Wentzellophyllum cf. kueichowense, Hayasakaia sp.
Age
Depositional setting
It is interpreted as a shallow-sea carbonate platform
Additional Information