Gandun Fm
Type Locality and Naming
The type section is located at Gandungou (gully), Yandun, Hami, Xinjiang. It was named by Wu Wenkui in 1958, and formally cited in The Paleozoic Erathem of Xinjiang in 1991.
Lithology and Thickness
Chert and Turbidites. Composed of abyssal sediments, mainly black massive siliceous and clayey rocks, siliceous siltstone, mudstone and silty mudstone, intercalated with minor quartzose sandstone and biotite-rich felsite at Gandun. Exposed thickness 3175 m.
Westward to the south of Dacaotan, the thickness reaches 6960 m (!), with normal clastic rock and pyroclastic rock increasing and metamorphism deepening.
Relationships and Distribution
Lower contact
Uncertain: Bottom unexposed
Upper contact
Conformable contact with the overlying Wutongwozi Fm
Regional extent
Distributed on the north slope of Qoltag (Mt.) and southern margin of the Hami basin, extending from E-W to NE
GeoJSON
Fossils
Northeast of Gushui, it yields Corals Yuanophyllum sp., Amygdalophyllum sp., Carcinophyllum sp., Rhodophyllum sp., Lithostrotion sp., Palaeosmilia sp., etc.,
Age
Depositional setting
It is interpreted as abyssal sediments
Additional Information