Lamaya Fm
Type Locality and Naming
The first area survey team of Sichuan Geological Bureau named the formation in 1961, and the third area survey team was publicly quoted for the first time in 1974. The named section is located in Lamaya, Reke District, Litang County, Sichuan Province. The reference section is located in EduoZhuoxi, XiongLong Township, Hexi District, Xinlong County, Sichuan Province.
Synonym:
Lithology and Thickness
It is composed of a set of dark gray hard quartz sandstone, feldspar quartz sandstone, interbedded with black carbonaceous slate and silty slate, and local coal interbedded line or coal seam. The thickness is between 2000 and 5000 m. The thickest area is up to 7000 m. In the south and east, the thickness is large, and in the west and north, the thickness becomes thin until the tip goes out.
Relationships and Distribution
Lower contact
The light gray thick feldspar quartz sandstone at the bottom is conformable contact with the top shale of the underlying Lanashan Fm
Upper contact
The top is unconformable contact with the bottom conglomerate of the overlying Yingzhunnianga Fm
Regional extent
It is only exposed in the north of Zhongdian area and is characterized by the occurrence of thick sandstone.
GeoJSON
Fossils
There are plant fossils in the upper part, including Neocalamites carrerei, Cladophlebis raciborskii, Clathropteris meniscioides, Pterophyllum ptilum, Anomozamites loczyi, Nilssoni opteris jourdyi; There are bivalve fossils in the lower part, such as Yunnanophorus boulei, Palaeoneilo peelii.
Age
Depositional setting
This group belongs to the clastic rock deposits of inland basin facies.
Additional Information