Yaxier Gr
Period:
Devonian
Age Interval:
D1? (22), Early Devonian?
Province:
Xizang (Tibet)
Type Locality and Naming
The type section is located at the south hill of Lazhulong-Yaer Lake area, Rutu of Xizang Zhang Autonomous Region. It was named by Zhang Bingao and He Guoxiong in 1984.
Lithology and Thickness
Sandstone. The Group, 330 m thick, is composed of grayish-white quartz sandstone and grayish-black to grayish-white siliceous limestone intercalated with marble.
Lithology Pattern:
Sandstone
Relationships and Distribution
Lower contact
It rests probably disconformably on the Lower Silurian.
Upper contact
It is overlain conformably by the Lazhulong Fm.
Regional extent
The Formation is mainly seen in the South Hill of Luzhulong-Yaxier Lake of Rutu area, westernmost Tibet.
GeoJSON
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Fossils
No fossils are reported.
Age
Early Devonian? (tentative placement on regional chart is within-Pragian through Givetian
Age Span:
S
Beginning stage:
Pragian
Fraction up in beginning stage:
0.5
Beginning date (Ma):
411.46
Ending stage:
Givetian
Fraction up in the ending stage:
1.0
Ending date (Ma):
378.90
Depositional setting
Depositional pattern:
Additional Information
Chinese version included comment that it includes layers of "Griotte" = red nodular limestone?
Compiler:
(Xian Shiyuan)