Kadong Fm
Type Locality and Naming
It was named by Wang Naiwen, Liu Guifang, Chen Guoming. The naming section is located to the west of the Kadong Village, Doqie (Dojiu) District, Langkazi County, Tibet (E 90°40′, N 28°45′).
Synonym: Seems in same stratigraphic position and lithologic description as the late Jurassic Weimei Fm (not in this Lexicon) between the Zhela Gr and Sangxiu Fm.
Lithology and Thickness
Composed of a set of grey and grey-yellow clastic deposits. Lower member consisting of grey-yellow medium-, and thin-bedded, and medium-, and thick-bedded coarse-grained quartz-sandstone, intercalated with a small amount of thin-bedded siltstone, silty and calcareous shale and sandstone containing locally pebbles. Upper member representing grey silty, calcareous and siliceous shales and siltstone, containing a great amount of sandy and calcareous concretions, and being intercalated with andesite and tuffaceous sandstone. Thickness of this formation is over 200 m; but no base of it has been found.
Relationships and Distribution
Lower contact
No base has been found. In some areas the formation is in an unconformable contact with the underlying Bajiutang Formation. (upper Zhela Gr) of early-Late Jurassic.
Upper contact
Its top part consisting of grey silty shale is in a conformable contact with the basal part consisting of grey crystal andesite intercalated with siliceous shale of the overlying Sangxiu Fm (K1).
Regional extent
The formation is distributed mainly in the areas of Doqie and snow-covered area of Longbu, Langkazi County, with a thickness of 200-350 m.
GeoJSON
Fossils
In the area of Kadong it yields abundant ammonites fossils as represented by Calliptychoceras, Neocosmoceras, Neocomites, Kilianella, Sarasinella, Parandiceras, Spiticeras, Protetragonites, Himalayites, Haplophylloceras strigeli.
Age
Depositional setting
Additional Information