Huakaizuo Fm
Type Locality and Naming
The type section is located in the area of Bazhulu-Huakaizu-Yangbi River about 36 km south of the Yangbi County Town, Yunnan Province, with the section at Heping Township of Jinggu County, Yunnan Province serving as its reference section. It was named by the No. 1 Regional Survey Party of Yunnan Province in 1973.
Synonym: （花开左组）
Lithology and Thickness
It is composed largely of alternating layers of purple, grey-violet and yellow-brown quartz-sandstones, siltstones and purple and grey-violet mudstones. It is with a thickness of 492 m.
Relationships and Distribution
Lower contact
Its basal part with a 2 m thick layer of purple micro-conglomerate is in a conformable contact with the underlying Yangjiang Fm. In Pu'er region, the next older unit is the Zhangkezhai Fm.
Upper contact
Regionally, the schematic strat column indicates the next younger unit as Hepingxiang Fm
Regional extent
The formation is distributed extensively in the area of Lanping-Simao, western Yunnan, with a basically consistent lithology of it from place to place, and with a slightly changeable thickness of 200-747 m. On the section at Heping Township the formation is intercalated with more yellow-green and yellow mudstones and sandstones, with a thickness of 223 m.
GeoJSON
Fossils
It yields bivalves as represented by Psilunio chaoi, Undulatula yunnanensis; and Chareae as represented by Euaclistochara lufengensis and E. nuguishanensis.
Age
Depositional setting
Additional Information