Hongquan Fm
Type Locality and Naming
The type section is located at the Daquan 10 km to the north of the Hexibao Railway Station on the Lanzhou-Xinjiang Railway in the territory of Gansu Province. It was named by Liang Jiande et al., in 1977, and was cited officially by the Compiling Group on the Regional Stratigraphic Chart of Gansu Province in 1980.
Lithology and Thickness
Conglomerate and Clastics. Composed of purplish-red conglomerate and pebble-bearing coarse-grained sandstone, intercalated with siltstone and clayey siltstone, with its middle part containing 5 m-thick grey-green clayey siltstone and clayey shale; with it top part being intercalated with several layers of siliceous marls. Its basal part consists of a purple conglomerate layer. Total thickness is 141 m.
Relationships and Distribution
Lower contact
Disconformable contact with the underlying Xiashihezi Fm (lower Shihezi) Fm or the Dahuanggou Fm
Upper contact
Conformable or disconformable contact with the overlying Daquan Fm
Regional extent
Distributed in the areas of Dahuanggou of Synan County, Daquan and Daqinggou of Jinchang City, and Wufuo Temple of Jingtai County.
GeoJSON
Fossils
Plant fossils (phytolites) such as the Pecopteris lativenosa, P. tenuicostata, Compsopteris wongii, Zamiopteris glossopteroides, Taeniopteris sp., Noeggerathiopsis sp., as well as Ostracoda fossils
Age
Depositional setting
It is interpreted as a river facies.
Additional Information