Guanziyao Fm
Type Locality and Naming
The type section is located from Lijiawan to Dawushang (104o59’E-25 o54’N), 2 km southwest of lead works of Pu’an County, Guizhou Province. It was named by Hou Hongfei and Xu Guirong in 1964.
Lithology and Thickness
Limestone, dolomite. This formation of carbonate rocks, 605 m thick, can be divided into three members: Lower -- Lijiawan Member, is composed of dark-gray to gray-black thin- to thick-bedded marl and dolomitic limestone.
Middle -- unnamed limestone part, consists of dark-gray medium- to thick-bedded fine-grained limestone and marl.
Upper -- unnamed dolomite part, is composed of dark-gray to grayish-white medium- to thick-bedded dolomite, crystalline limestone and marls.
Relationships and Distribution
Lower contact
No underlying formation is exposed beneath the Guanziyao Fm in type locality.
Upper contact
The upper boundary of this formation is assigned at the disappearance of crystalline limestone and the appearance of chert limestone at the conformable contact with the overlying Huohong Fm.
Regional extent
It is restrictively distributed at Guanziyao area in Pu’an County.
GeoJSON
Fossils
It contains coral Calceola sandalina and brachiopod Puanospirifer in the Lijiawan Member. The other fossils are corals, stromatoporoids and brachiopods, among which the Zdimir spp. are leading form.
Age
Depositional setting
It is interpreted as a carbonate platform margin.
Additional Information