Pengjiu Fm
Type Locality and Naming
The type section is located at Pengjiu Village, Dazhi Country, Qinzhou County, Guangxi Zhuang Autonomous Region. It was named by Yin Bao’an, Chen Jian and Cai Ninghong in 1994.
Lithology and Thickness
Fining-upward clastics. Representing a suite of terrigenous coarse clastic rock strata composed of conglomerate, pebble-bearing sandstone, sandstone, and siltstone. Lower part is composed of light-grey massive conglomerate, conglomeratic sandstone and pebble-bearing sandstone, intercalated with siltstone. Middle part consists of light-grey-green and light-grey thin- and thick-bedded clayey siltstone and siltstone. Upper part is composed mainly of grey and dark-grey thin- and medium-bedded siltstone and clayey siltstone, intercalated with fine-grained sandstone and pebble-bearing sandstone. Total thickness of 1600-5044 m.
Relationships and Distribution
Lower contact
Unconformable contact with the underlying Bancheng Fm
Upper contact
Disconformable contact with the overlying Banba Fm of the Middle Triassic Epoch
Regional extent
Distributed chiefly in the areas of Lingshan, Qinzhou, Fangcheng and Dongxing Counties, and in a NE-SW trend.
GeoJSON
Fossils
Plant fossils such as Gigantopteris sp., Ullmannia aff. bronnii, Pecopteris hemitelioides, etc.; Brachiopods such as Leptodus sp., Neochonetes sp., Chonetes sp., Dictyoclostus cf. boliviensis var. chitichunensis, etc.; and Bivalves such as Eoschizodus sp., Aviculopecten? simplicostata, Euchondria sp., etc.,
Age
Depositional setting
It is interpreted as paralic-facies deposits (interfingered marine and continental coastal environments).
Additional Information
GeoJSON estimate by Can Cai and Xinyi Zhang (Chengdu Univ. Tech. students)