Boqu Gr
Period:
Devonian
Age Interval:
D2-3 (24), middle and late Devonian
Province:
Xizang (Tibet)
Type Locality and Naming
The type section is located from Jiacun to Yali in Nyalam County, Xizang Autonomous Region. It was named by Wang Yigang et al. in 1974.
Lithology and Thickness
Sandstone. The Group is a set of gray medium-bedded medium- to coarse-grained feldspathic quartz sandstone intercalated with partly silty shale. It is 250 m in thickness.
Lithology Pattern:
Sandstone
Relationships and Distribution
Lower contact
Conformably on the marl and sandy shale interbeds of Liangquan Fm.
Upper contact
Overlain by the dark-gray to black shale of the Yali Fm.
Regional extent
It is distributed in the area of Burang--Nyalam, Tingri and Yadong.
GeoJSON
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Fossils
It contains rare fossils, only plant fragments.
Age
middle and late Devonian
Age Span:
S
Beginning stage:
Emsian
Fraction up in beginning stage:
0.8
Beginning date (Ma):
397.54
Ending stage:
Famennian
Fraction up in the ending stage:
0.67
Ending date (Ma):
363.19
Depositional setting
It is interpreted as a sublittoral shallow-water facies deposition.
Depositional pattern:
Additional Information
Compiler:
(Xian Siyuan)