Hongqi Fm
Type Locality and Naming
The type section is located in the Hongqi Coal Mine to the Jianchang area of Tao’an County, Jilin Provence; with its reference section being situated in the area of Xishala, Zhalute Banner, Inner Mongolia. It was named by the No. 217 Prospecting Team under the Coalfields Administration of Jilin Province in 1960.
Synonym: （红旗组）; In the Inner Mongolia it is known also as the “Tatayingzi Formation”.
Lithology and Thickness
It is composed essentially of dark-grey siltstone and mudstone, intercalated with sandstone, containing many mineable coal layers, with its basal part being possessed of a layer of thin-bedded or lenticular conglomerate. It is with a thickness of about 704 m.
Relationships and Distribution
Lower contact
Upper contact
It unconformably overlies the late Permian volcanic rocks. Regionally, the next older unit is the Jiaoliuhe Fm of late Triassic volcanics.
Regional extent
It is distributed largely in the areas of Hongqi and Wanbao of Tao’an County, Jilin Province, and of Julihei, Xishala and Tatayingzi of the Zhalute Banner, and of Tashao Dam extending to Pingdingshan of the Balin Left Banner, Inner Mongolia, with a thickness varying in a range from 170 m to 1000 m.
GeoJSON
Fossils
It yields an early-stage assemblage of the Coniopteris- Phoenicopsis flora consisting of 21 genera and 45 species of plants whose important members are: Equisetum asiaticum, Neocalamites carrerei, Todites princeps. T. williamsoni, phlebopteris brauni, Clathropteris meniscioides, Thaumatopteris schenki, Clathropteris ingens, Pterophyllum sp., Anomozamites cf. major Nilssonia sp., Ginkgo ex. gr. sibirica, Phoenicopsis angustifolia, Czekanowskia rigida, Cyadocarpidium sp., as well as spore-pollen fossils as represented by the Osmundacites-Cyathidites-Chordasporites assemblage. In addition, there are found to occur a small amount of bivalves such as Ferganoconcha, and etc.
Age
Depositional setting
The formation represents intermontane-basin fluvial-lacustrine and swamp-facies deposits.
Additional Information