Dianzhong Fm
Period:
Paleogene
Age Interval:
Paleocene, (9a)
Province:
Xizang (Tibet)
Type Locality and Naming
The naming section is located near Dianzhong 39 km southwest of Linzhou County, Tibet. Named by the Regional Party of Tibet in 1991.
Lithology and Thickness
Sequence of predominantly andesite and andesitic and dacitic pyroclastic rocks, locally accompanied by a typical alkaline island-arc volcanic rock association of rhyolitic dacite. At the base there sometimes appears basal conglomerate. 1162 m thick. From east to west the acidity and pyroclastic rocks increase.
Lithology Pattern:
Volcanics
Relationships and Distribution
Lower contact
Unconformable contact with the underlying Late Cretaceous Shexing Fm.
Upper contact
Unconformable contact with the overlying Eocene Nianbo Fm.
Regional extent
This formation is distributed in the vicinity of Linzhou and Namling, Lhasa.
GeoJSON
null
Fossils
Age
It has Rb-Sr ages of 88±2–86±1.6 Ma and seven K-Ar ages such as 60, 51.5 and 51.46 Ma.
Age Span:
Beginning stage:
Danian
Fraction up in beginning stage:
0.0
Beginning date (Ma):
66.04
Ending stage:
Thanetian
Fraction up in the ending stage:
1.0
Ending date (Ma):
56.00
Depositional setting
Depositional pattern:
Additional Information
Compiler:
Tao Deng, Yuanqing Wang, Qian Li, et al.