Gumu Fm
Type Locality and Naming
It was named by Guangdong Party of Geological Survey at Gumu village, Yunfu County, Guangdong Province. The paratype section is located at the Qiping Tree Farm, Cengxi County, Guangxi Zizhiqu. The name of Lingshan Group was rejected by Yin Baoan (eds., 1997).
Synonym: (古墓组)
Lithology and Thickness
The formation is dominated by fine-grained sandstone, litharenite and siltstone, interbedded with shale. The thickness of the formation is over 300 m.
Relationships and Distribution
Lower contact
It is contacted conformably with the underlying Dagangding Fm of Upper Ordovician.
Upper contact
It is contacted conformably with the overlying Hepu Fm
Regional extent
It is exposed in the Fangchenggang, Qinzhou, Hepu, Bobai, Luchuan, Yulin, Beiliu, Rongxian, Cengxi areas of southeastern Guangxi, and Yunfu area of Guangdong. The thickness and the material of litharenite are increased gradually southwestward. The thickness can be up to 3295-4725 m at Qinzhou and Fangchenggang area.
GeoJSON
Fossils
The formation is rich in graptolite fossils, includes Normalograptus persculptus, Akidograptus acuminatus, Pristiograptus cyphus, Demirastrites triangulatus, D. convolutus, Monograptus sedgwickii, Spirograptus turriculatus, S. crispus, Monoclimacis griestoniensis, Stomatograptus grandis, Oktavites spiralis etc., and trilobite Encrinuroides sp., Coronocephalus rex, etc. and brachiopoda Nalivkinia sp., Zygospraella sp. Rhynchonella sp., etc., at some certain levels.
Age
Depositional setting
Additional Information