Guche Fm
Type Locality and Naming
The type section is located near Yingtang Village of Dale in Xiangzhou County, Guangxi Zhuangzu Autonomous Region. It was named by Hou Hongfei and Xian Siyuan in 1975.
[Figure Locations of Dale Fm (A, B) and Gupa Fm and Guche Fm (C) in Dale area]
Lithology and Thickness
Limestone. It is dominated by medium-bedded detrital and bioclastic limestone with chert bands and nodules, dolomitic limestone and clayey bioclastic limestone, intercalated with calcareous shale and mudstone in the lower part. There is an upward increase in the interbeds of clayey limestone with bioturbation structures, mudstone and siltstone. The thickness is about 170 m.
[Figure - Outcrop of Guche Fm showing the silicified megafossils, length of harmer 26 cm.]
Relationships and Distribution
Lower contact
At the bottom, it is easily separated by the appearance of chert-bearing limestone from the underlying calcareous shale of the Gupa Fm with a conformable contact.
Upper contact
It is conformable contact with overlying Changchun Formation by appearance of gray
green shale for separation..
Regional extent
This formation is widely distributed along the west side of Dayaoshan Mt..
GeoJSON
Fossils
It yields abundant Brachiopods Athyrisina squamosaeformis, Indospirifer morerchuanensis, I. changuliensis sp., Emanuella aff. takuanensis , “Uncinulus” spp., Yingtangella sulcatilis and Corals Calceola sandalina, Utaratuia sinensis, Microplasma devonica and Pseudomicroplasma dellectum; and other ostracods, trilobites and bryozoans
Age
Depositional setting
It is interpreted as a shallow subtidal environment.
Additional Information