Congla Fm
Type Locality and Naming
The type section is located in Southern Conglashan Mountain, Jiangda County, Tibet Autonomous Region, and was named by the third regional geological group of Bureau of Geology of Sichuan in 1971. Original Congla Formation represented a suite of flysch-kind deposit in Jiangda County, Tibet Autonomous Region, which formed during Anisian to Ladinian.
Synonym: The Chengdu Institute of Geology and Mineral Resources of the Chinese Academy of Geological Sciences and the regional survey team of the Sichuan Bureau of Geology and Mineral Resources (1992) combined the Walasi Fm with the overlying Congla Formation, collectively known as the Wakasi Fm.
Lithology and Thickness
This formation is characterized by flysch sediments, consisting of rhymetic grey, dark grey conglomerate, sandstone and killas. With frequently changes in rhymes. Base of this formation was marked by the occurrence of grey conglomerate. Thickness of single rhyme varies from 2-20 m and the total thickness is 333.1 m.
Relationships and Distribution
Lower contact
This formation is conformably with the underlain Middle Triassic Walasi Fm
Upper contact
It is unconformity to the overlying Upper Triassic Dongdu or Jiapila Fm
Regional extent
Distribution of this formation is restricted to Jiangda and Mangkang of Tibet Autonomous Region.
GeoJSON
Fossils
Ammonoid: Protrachyceras-Balatonites zone; Bivalve: Posidonia sp.; Plant: Neocalamites sp.
Age
Depositional setting
Turbidite
Additional Information
The Jiapila and the underlain Walasi formations were combined into a Walasi formation by Chengdu Institute of Geology and Mineral Resources, Chinese Academy of Geological Sciences and Sichuan Geological Survey in 1992.