Luojingtan Fm
Type Locality and Naming
Jianghan Basin. The Luojingtan Formation was erected jointly by the Petroleum Geological Team of the Hubei Bureau of Geology and Mineral Resources and the North China No.106 Geological Team under the Ministry of Petroleum Industry in 1960. The type locality for the designation is in Luojingtan of Yichang of Hubei. The reference section is from Zhujiazui of Yichang to Shilingzi of Dangyang of Hubei.
Lithology and Thickness
The Luojingtan Formation is mainly represented by gray red, purple red and gray thick-bedded and massive conglomerate with siltstone. It is 273.2 m thick.
[Figure: Luojingtan Formation (lower) and Honghuatao Formation in Sunjiaxi section of Yidu, Hubei]
-Honghuatao Fms Yidu Hubei.png)
Relationships and Distribution
Lower contact
Its base marked by gray red conglomerate interbedded with brick-red grit is distinguished from the Wulong Fm consisting of brick-red siltstone with light gray granule conglomerate. The formation is in conformable or disconformable contact with the underlying Wulong Fm and locally overlaps the strata prior to the Cretaceous.
Upper contact
Its top is separated by the appearance of brown yellow and bright red thick-bedded fine sandstone of the base of the Honghuatao Fm. It is in conformable or disconformable contact with the overlying strata.
Regional extent
The formation occurs in Luojingtan and Tumenya of Yichang and in Jingmen and Zhongxiang of Yuquansi of Dangyang of the Jianghan Basin of central Hubei. It does not vary considerably in lithology and decreases in thickness from west to east. It is called the Xiaodong Formation in the Mayuan Basin.
GeoJSON
Fossils
In the eastern part of the Jianghan Basin, the Hojiapo Fm yields ostracods Cypridea cavernosa.
Age
Depositional setting
It is of continental deposition.
Additional Information