Kawenggou Gr
Type Locality and Naming
The type section is located at Kawenggou, Tongba Region, Muli County, Sichuan Province. It was named by the 3rd Regional Geological Survey Party under the Sichuan Geological Bureau in 1972.
Lithology and Thickness
Limestone and Clastics. In the type section the Lower formation of the group consists of interbeds of grey and grey-black siliceous rocks, limestone, sandstone and slate, intercalated with black limestone lenses and conglomeratic limestone, with a thickness of over 802 m. The lower part of the Upper formation consists of the grey and black, and the upper part of the Upper formation is composed of grey-white and pink thin- and thick-bedded limestone, siliceous limestone and clayey limestone, intercalated with marl, metamorphosed feldspar-quartz sandstone and carbonaceous slate, with a thickness of 570 m.
Relationships and Distribution
Lower contact
Conformable contact with the underlying Maowu Gr of the Yangsingian Epoch
Upper contact
Disconformable contact with the overlying Cigang Fm of the lower Triassic Series
Regional extent
In the Maowu section of the Muli County the Lower formation of the group is composed interbeds of grey-green basic agglutinate tuff and basic welded volcanic breccia, intercalated with grey limestone, with the intercalated beds of limestone yielding Fusulinida such as Nankinella inflata, corals such as Waagenophyllum sp., with a thickness of 1252 m. And the Upper formation consists of grey phyllite, intercalated with dark-grey thin-bedded limestone, with the limestone at the top representing a brecciated one, yielding such Fusulinida as the Nankinella sp., Eoverbeekina cf. sphaerulinaeformis, Staffella sp., Sphaerulina sp., and corals such as Waagenophyllum sp., with a thickness of 115 m. In the area of the Yangwozi, Xiqiu Country, Muli County, the Lower formation of the Kawenggou Gr consists of black brecciated limestone and grey-yellow siltstone, intercalated with massive limestone and yellow-green slate, yielding Fusulinida as represented by the Codonofusiella kwangsiana, Reichelina changhsingensis; brachiopods such as Enteletes kayseri, Squamularia sp., etc., with a thickness of 125 m, and is distributed in the Tongda and Qiongyi areas of the Muli County.
GeoJSON
Fossils
Lower formation yields Brachiopods represented by Hemiptychinanana, Martinia squamularioides, M. orbicularis, M. osborui, Enteletes kayseri, E. aff. wordensis, etc.
Upper formation yields Fusulinida as represented by the Gallowaiinella meitienensis; brachiopods such as Martinia transversalis, M. contracta, Uncinunellina timorensis, U. mongolicus, Squamularia waageni, S. grandis, Waagenoconcha cf. purdoni, Semibrachythyrina cf. mahaensis, Leptodus richthofeni, and plant fragments, etc.,
Age
Depositional setting
Additional Information