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
Zuogong Formation

Zuogong Fm


Period: 
Triassic

Age Interval: 
Middle Late Triassic (TJ35)


Province: 
Xizang (Tibet)

Type Locality and Naming

In 1983, Chen Bingwei and Ai Changxing measured the section at Dongda Village, Zuogong County, Tibet. In 1985, Zou Chengjing and Han Zizhang built a Zuogong Fm based on the section.

Synonym: Chengdu Institute of Geology and Mineral Resources, Chinese Academy of Geological Sciences, and District Investigation Group of Sichuan Bureau of Geology and Mineral Resources (1992) named the Early Late Triassic Norian strata in the area of Zuogong as Jiapira Fm, and compared it with the upper part of the Late Triassic Norian strata in the area of Tuba, which was from the Late Triassic Carnian to the Early Norian.


Lithology and Thickness

Lower clastic member consists of purplish red conglomerate, gray-white quartz sandstone with thin layer marl, calcareous mudstone and reef limestone. Middle limestone member is composed of gray limestone, argillaceous limestone and intermediate basic volcanic interlayer. Upper clastic member is interbedded with lime-black sand shale with a little limestone and coastal coal seam. Its thickness is greater than 1100 m.


Lithology Pattern: 
Sandy limestone


Relationships and Distribution

Lower contact

The bottom boundary is marked by the initial occurrence of purplish red conglomerate above the pseudo-conformity surface, which is the pseudo-conformity contact with the underlying Middle Triassic Dongdacun Fm

Upper contact

The top boundary is marked by the final occurrence of grayish-black sand and shale

Regional extent


GeoJSON

null

Fossils

Montivaltia sp., Thecosmilia sp., Monotis cf. salinaria, Cardita cf. shombodes


Age 

Schematic stratigraphic section indicates late Carnian.

Age Span: 

    Beginning stage: 
Carnian

    Fraction up in beginning stage: 
0.75

    Beginning date (Ma): 
229.73

    Ending stage: 
Carnian

    Fraction up in the ending stage: 
1.0

    Ending date (Ma):  
227.30

Depositional setting


Depositional pattern:  


Additional Information


Compiler:  

Zhang Shunxin, Zhou Ze and Tong Jinnan.