Zhoujiayuan Fm
Type Locality and Naming
It was named by the Regional Survey Party of Jiangxi Province in 1978, and was first cited publicly by the Geological Bureau of Jiangxi Province. The naming section is located at the point about 400 m west of the Zhoujiayuan Village of Dongxiang County, Jiangxi Province.
Synonym: （周家源组）
Lithology and Thickness
Lower member is composed of purple and grayish-green pebble-bearing argillaceous siltstones and rhyolitic tuffs, intercalated with a small amount of sandy conglomerates and calcareous siltstones, with a thickness of over 91 m. Upper member is composed of grey-violet and grey-white rhyolites, rhyolitic dacites and trachytic andesites, with a thickness of about 105 m.
Relationships and Distribution
Lower contact
Only in the drilling wells of the Ruyiting area of Le’an County have the ignimbrite and purple sandy conglomerate from the basal part of the formation been found to overlie unconformably the Sinian System.
Upper contact
Regionally, the schematic strat column indicates the next younger unit as Huacaojian Fm
Regional extent
It is distributed in a limited region and is found to occur in the Chongrenxiang Mts, with a thickness of about 267 m. In the Fuzhou, Dongxiang and Jinxi areas in the southern part of Dongxiang County some exposures of the formation are also found to occur.
GeoJSON
Fossils
Age
Depositional setting
The formation belongs to volcanic eruption-facies deposits.
Additional Information