Gumu Fm
Type Locality and Naming
The type section is located near Gumu Village, 10 km south of the Wenshan Zhuangzu and Yizu Zizhizhou, Yunnan Province. It was named by Fang Runsen in 1973 and quoted officially by Yun Ya in 1978.
Lithology and Thickness
Limestone. The lower part of the formation is composed of light gray thick-bedded and massive limestone with dolomitic limestones, 102.63 m thick. The middle and upper parts consist of medium to thick-bedded bioclastic limestone and partial argillaceous limestone and reef limestone, 431 m thick. Southward to Laomaozi of Yangliujin, about 5 km apart from Gumu, the thickness decreased to 330 m.
Relationships and Distribution
Lower contact
It has a conformable contact onto the underlying dolomite of the Bajiaoqing Fm in the type locality, but no well-defined boundary. In the Xiaochang, 5 km east of Gumu, the Formation overlies on the breccia limestone of Duozui Fm.
Upper contact
It is overlain by thick-bedded dolomite of the Qujing Fm, but also with no well-defined boundary.
Regional extent
The formation is scattered distribution in the Southern Wenshan, Mengzi, Xizhu, Funing, Yanshan and Qiubei areas of southeastern Yunnan.
GeoJSON
Fossils
It contains abundant Corals: Thamnophyllum diandongnanensis, Neospongophyllum zhichangense, Pterorhiza yunnanensis, Lyrielasma sp., Enterolasma yunnanense, Cystiphylloides mirabilis, Tryplasma devoniana, Acanthophyllum heterophyllum, Favosites spp., Squameofavosites spp.; and Brachiopods: Megastrophia sp., Zdimir sp.
Age
Depositional setting
It is interpreted as an open carbonate platform facies.
Additional Information