Zhenshui Fm
Type Locality and Naming
Nanxiong Basin. Zhang Xianqiu erected the Zhenshui member of the Nanxiong Formation in the report on the study of the Dafeng section of Nanxiong (unpublished) in 1981. The section for the designation is in Dafeng of Nanxiong of Guangdong.
Lithology and Thickness
The Zhenshui Formation is mainly represented by a set of alternating coarse and fine-grained red clastic rocks, which is roughly divided into two parts. Lower part is built up by grayish brown and brownish red sandy conglomerate and gravel-bearing sandstone. Upper part is brown red siltstone interbedded with silty mudstone. It is 311.4 m thick.
Relationships and Distribution
Lower contact
The conformable base marked by brick-red gravel-bearing sandstone is distinguished from the Zhutian Fm marked by brown red silty mudstone with gray green marl.
Upper contact
The conformable top is bounded by the appearance of red mudstone at the base of the Shanghui Fm. But neaby, the Danxia Fm (red sandstones) overlie the Nanxiong Gr.
Regional extent
The formation is distributed in the Shaoguan and Huaiji areas of north Guangdong. It is persistent in lithology and does not vary considerably in thickness. It is more than 275 m thick in Huaiji, 263.2 m in Dafeng of Nanxiong, 221.4 m in Shatouau of Nanxiong. It is in conformable contact with both the overlying and underlying strata.
GeoJSON
Fossils
The formation yields ostracods Candona postrotunda, Cypridea subtera, C. xindianensis, C. guangzhouensis, Metacypris kaitunensis, Parailyocypris taizhouensis; Charophytes Grovesichara changzhouensis, Maedlerisphera shanggangensis; Dinosauria Tarbosaurus and Microhadrosaurus, as well as Dinosaurian eggs.
Age
Depositional setting
It belongs to lacustrine deposition.
Additional Information