Rimowa Fm
Type Locality and Naming
Himalayan North Belt. The Rimowa Formation was erected by Wang Naiwen, Liu Guifang and Chen Guoming in 1983. The section for the designation is from the Kadong Village to Zuomadingla through Duoque (90°07′E; 28°08′N). The reference section is from Shelang to Bajiutang through Reshan of Gonboxue (Longbuxue district) of the Nagarze County, Xizang (91°00′E; 28°06′N).
Lithology and Thickness
The Rimowa Formation is divided into two members. Lower member is represented by gray, grayish yellow and grayish green sandstone, sandy conglomerate, conglomeratic siliceous limestone, bio-limestone, marl and calcareous shale, with a thickness of 50 m, bearing ammonites, abundant brachiopods, and belemnites. Upper member is light gray, gray and grayish green silty shale and siltstone with gray calcareous shale, with a thickness of 150 m, bearing bivalves, ammonites, etc. The Rimowa Formation is 200 m thick.
Relationships and Distribution
Lower contact
The base of the formation made up of sandy conglomerate, sandstone and siliceous shale lies conformably on the underlying Sangxiu Fm.
Upper contact
Regional extent
The present formation mainly occurs in the Duoque and Gongboxue of the Nagarze County. In the Gongboxue district, sandy conglomerate and conglomeratic siliceous limestone are not observed, but limestone lenses are observed. It contains proliferous biotas, suggestive of normal neritic sedimentary environment.
GeoJSON
Fossils
In Kadong and Gongboxue, the lower part of the Rimowa Formation contains ammonites Crioceratites cf. loryi, Olcostephanus sp., O. magnus, etc., brachiopods Peregrinella sp.; while the upper member ammonites Eulycoceras sp., etc. and bivalves Parainoceramus sp.
Age
Depositional setting
Additional Information