Zawangzi Fm

Himalayan North Belt. The Zawangzi Formation was erected by Wang Naiwen, Liu Guifang and Chen Guoming in 1983. The section for the designation is between the Kadong Village and Zuomadingla of the Duoque District of Nagarze County of Xizang (91°07′E; 28°02′N). The reference section is from the locus of the Gongboxue District to Bajiutang through Shelangre of the Nagarze County, Xizang (91°00′E; 28°06′N).

The Zawangzi Formation is divided into two members. Lower member is built up by gray yellow siliceous shale with ferruginous and siliceous nodules, intercalated with 30 m thick dark gray carbonaceous shale, with 20 m thick gray yellow ferruginous and siliceous siltstone, measuring 200 m thick. Upper member is built up by gray yellow siliceous shale with several layers of siliceous shale with gray clayey limestone nodule of lenses, with a thickness of 200 m.

In the Duoque area, the lower member of the formation yields ammonites Pseudohaploceras sp., Acrioceras aff. dissimilis, etc. while the upper member ammonites Desmoceras cf. merriami, Parahoplites sp., Cheloniceras (Cheloniceras) negarzensis, Acrioceras sp., etc. No identifiable fossils have been discovered in the Gongboxue District