Home Multi-Country Search About Admin Login
Cenozoic
Cretaceous
Jurassic
Triassic
Permian
Carboniferous
Devonian
Silurian
Ordovician
Cambrian
Neoproterozoic
Mesoproterozoic

Search by
Select Region(s) to search
Hold Ctrl (Windows/Linux) or Command (Mac) to select multiple
Xiayacun Andesite Formation
Click to display on map of the Ancient World at:
Xiayacun Andesite Fm base reconstruction

Xiayacun Andesite Fm


Period: 
Permian

Age Interval: 
P3 (60), late Permian


Province: 
Xizang (Tibet)

Type Locality and Naming

The type section is located in the Xiaya Village in the vicinity of the Xiba Region, Chando County (Qamdo County), Tibet. It was named by the 1st Geological Expedition under the Tibetan Bureau of Geology and Mineral Resources in 1976.


Lithology and Thickness

Volcanics. Composed of grey-green and purplish red andesite, andesitic agglomerate, tuff, tuffaceous sandstone and amphibole andesite, with a thickness of over 253 m.


Lithology Pattern: 
Lava


Relationships and Distribution

Lower contact

Unconformable contact with the underlying Kaxiangda Fm of the Upper Permian Series

Upper contact

Unconformable contact with the overlying conglomerate of the Jiapila Fm of the Upper Triassic Series. However, regionally, the next younger unit is the shallow-marine Malasngdou Fm of earliest Triassic or the coeval sandstone of the Jiazhila Fm.

Regional extent

Distributed in the Chando (Qamdo) Region


GeoJSON

{"type":"Feature","geometry":{"type":"MultiPolygon","coordinates":[[[[98.67,31.6],[98.69,31.45],[98.64,31.34],[98.55,31.2],[98.3,31.13],[98.01,31.07],[97.73,31.04],[97.51,31.09],[97.32,31.16],[97.18,31.32],[97.15,31.48],[97.18,31.64],[97.28,31.77],[97.46,31.88],[97.74,31.96],[97.92,31.99],[98.06,31.99],[98.26,31.98],[98.44,31.85],[98.53,31.73],[98.62,31.65],[98.67,31.6]]]]}}

Fossils


Age 

Assigned as late Permian

Age Span: 

    Beginning stage: 
Changhsingian

    Fraction up in beginning stage: 
0.5

    Beginning date (Ma): 
253.07

    Ending stage: 
Changhsingian

    Fraction up in the ending stage: 
1.0

    Ending date (Ma):  
251.90

Depositional setting


Depositional pattern:  


Additional Information


Compiler:  

Wang Yujing

GeoJSON estimate by Longgang Ye and Yuyin Li (Chengdu Univ. Tech. students)