Guijiatun Fm
Type Locality and Naming
The type section is located near Guijiatun of Xishan Hill in Qujing County (103o 42'E - 25o 30'N), Yunnan Province (see Cuifengshan Gr). It was named by Zhang Xinping in 1966, who assigned it as a Formation unit of Cuifengshan Gr.
[Figure Simplified geological map showing the locations of the type sections of Xishancun Fm (D1 x), Xitun Fm (D1 xt,), Guijiatun Fm (D1 g) and Xujiachong Fm (D1 xj) of Cuifengshan Gr in the West Hill of Qujing City, Yunnan Province.]
Lithology and Thickness
Sandy claystone. It is dominated by purplish-red medium- to thick-bedded mudstone intercalated with thin-bedded yellowish sandstone displaying well rhythmicity. However, in the upper part the purplish-red colored rock decreases, the yellowish-green rock increases and the mudstone increases. In the middle and upper parts, there are commonly small calcareous nodules. It is 350-400 m thick.
[Figure Outcrop showing the interbedded sandstone and claystone bands in different colors in the Guijiatun Formation at Guogaishan Hill.]
Relationships and Distribution
Lower contact
It has conformable contact with the underlying Xitun Fm.
Upper contact
It has conformable contact with the overlying Xujiachong Fm.
Regional extent
It is distributed mainly in the east of Yunnan at Xishan-Cuifengshan area of Qujing County.
GeoJSON
Fossils
It yields Plant Zosterophyllum myretonianum, Z. astraliannum, etc.; Spore Dibolisporites echinacerus, Dictyotriletes gorgoneus, Verrucosisporites polygonalis, Crassispora minuta; Fish Sanchaspis magalarostra- Qingmenaspis microculus Assemblage; Bivalve Modiomorpha crypta, and gastropods.
Age
Depositional setting
Non-marine deposits of littoral setting are suggested.
Additional Information