Jinji Fm
Type Locality and Naming
It was named by Sun Yunzhu, Zhang Youzheng as the “Jinji Group” in 1960. The naming section is located in the area of Jinji Mt, Kaiping County, Guangdong Province, with its reference section being situated at Tianmenao of Qujiang County.
Synonym: （金鸡组）
Lithology and Thickness
Composed of grey pebble-bearing sandstone, fine-grained sandstone, siltstone, silty mudstone and mudstone, intercalated with carbonaceous shales and tuffaceous sandstones, containing sandy concretions, with a thickness of 652 m.
Relationships and Distribution
Lower contact
It is in a conformable contact with the underlying Xiaoping Fm (not in Lexicon); regionally, the next older unit is the Genkou Gr of late Triassic.
Upper contact
Regionally, the schematic strat column indicates the next younger unit as Qiaoyuan Fm
Regional extent
The formation represents such deposits as predominated by marine clastic rocks, and is distributed extensively in Qujian and Qongyuan Counties of northern Guangdong, along the line stretching from Heyuan County to Jiexi County of eastern Guangdong; in the areas of Dapu and Meixian counties of northeastern Guangdong, and in Kaiping Enping and Yangchun counties of central Guangdong. Its thickness varies in a range from 128 m to 2500 m.
GeoJSON
Fossils
It yields Cephalopoda, ammonites, bivalves and plant fossils, with the Cephalopoda being represented by the Psiloceras planorbis-Arietites ammonites; with the bivalves belonging to Parainoceramus-Teinonuculang assemblage; and with the plants representing the Marattiopsis-Otozamites assemblage of the Dictyophyllum-Clathropteris flora.
Age
Depositional setting
The formation represents such deposits as predominated by marine clastic rocks.
Additional Information