Huajiahu Fm
Type Locality and Naming
The type section is located in the area of Zhumawan-Jiangjia Village in the vicinity of Huajia Lake of Echeng County, Hubei Province. It was named by the Regional Survey Party of Hubei Province as the “Huajiahu Group” in 1974.
Synonym: （花家湖组）
Lithology and Thickness
Lower member is composed of heteropachous alternating layers of yellow and yellow-green feldspar-quartz sandstones, siltstones and mudstones, with its basal part being possessed of a layer of sandy conglomerate. Middle member represents purple siltstone and mudstone, intercalated with yellow-brown sandstone. Lower part of its Upper member consists of grey and yellow-green pebble-bearing gritstones, gradating upwards into a rhythmite composed of fine-grained sandstone, siltstone and mudstone. Lower member is with a thickness of 122-208 m; Middle member is with a thickness of 328-560 m; Upper member is with a thickness of 30-275 m.
Relationships and Distribution
Lower contact
The formation represents a continuous deposition with the underlying Jinshandian Fm
Upper contact
Regionally, the schematic strat column indicates the next younger unit as Tongzuyuan Fm
Regional extent
It is distributed commonly in association with the Wuchang Group, yet with its exposures being incomplete in various regions. And good exposures of the formation can only be seen in the areas of Chepu of Puqi County, Jinshandian of Daye County, and Huajia Lake of Echeng County, with its maximum thickness being of 1049 m, but with a thickness of only 87 m in the area of Chepu, and with a thickness of about 564 m in the vicinity of Jinshandian area.
GeoJSON
Fossils
No fossils having been found.
Age
Depositional setting
It belongs to fluvial-lacustrine deposits.
Additional Information