Shihuadong Fm
Type Locality and Naming
The type section lies by the Shihuadong Reservoir of Yunrui Street, Baoshan County, Yunnan. It was named by Duan Lilan in 1973.
Synonym: Xiangshan Fm (upper) and Pumenqian Fm (lower) – see Additional information
Lithology and Thickness
Limestone. Gray, gray-yellow and gray-black moderately thick-bedded limestone, occasionally intercalated with thin-bedded micritic limestone, micritic pellet limestone, dolomitized micrite and micritic bioclastic limestone, with chert nodules and bands commonly developed. Thickness about 150 m, reduced to <100 m eastward.
Relationships and Distribution
Lower contact
Conformable contact with the underlying Yudong Fm
Upper contact
Conformable contact with the overlying Yunruijie Fm
Regional extent
GeoJSON
Fossils
Fossils are abundant, including Conodonts Gnathodus semiglaber, G. texanus, G. pseudosemiglaber and G. typicus; Corals Siphonophyllia, Keyserlingophyllum, Kueichouphyllum, Palaeosmilia, Diphyphyllum, Zaphrentites, Lophophyllum, Michelinia, etc. as well as foraminifers, brachiopods, crinoid calyx Cribanocrinus, Amphoracrinus, Stomiocrinus, Platycrinites, Synbathocrinus, Yunnanocrinus, etc.
Age
Depositional setting
It is interpreted as a
Additional Information
In 1983, Yang Zongren divided the Lower Carboniferous of the Baoshan area into the Xiangshan and Pumenqian formations. However, it is difficult to distinguish the upper Xiangshan Fm and the lower Pumenqian Fm lithologically, as they both contain chert nodules and bands, and there lacks a boundary indicator to identify the units. Besides, they were put forward later than the Yudong, Shihuadong and Yunruijie formations (The Regional Stratigraphic Scale of Yunnan Province, 1978), and so they should be abolished.