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
Benpulong Formation

Benpulong Fm


Period: 
Triassic

Age Interval: 
Late Middle Triassic (TJ31, TJ32)


Province: 
Qinghai

Type Locality and Naming

The type section is located in Yushu City, southern part of Qinghai Province, which named by Shida Ye and Tongshi Yang in 1982. In 1982, Ye Shida and Yang Tongshi divided the Middle Triassic of Yushu Jialong into the lower Gelong Gr (now Gelong Fm) and the upper Benpulong Gr (now Benpulong Fm).

Synonym: Benpulong Gr. This formation was once ascribed into Batang Group by Rongbiao Rao et al. (1987)


Lithology and Thickness

This formation is dominated by carbonates. Lower part that of 299 m is consisted of grey, purple massive limestone. Overlain by grey dolomitic limestone of 220 m, and covered by grey thick limestone of 77 m in the top.


Lithology Pattern: 
Limestone


Relationships and Distribution

Lower contact

The Benpulong Formation lies conformable above the Middle Triassic Gelong Fm

Upper contact

Contact relations with the next younger unit, Batang Gr of Late Triassic, is unclear. Stratigraphic column TJ32 for west Tangula Mtns indicate it is overlain by the Jiezha Gr (Dongmaolong Fm) in that region.

Regional extent


GeoJSON

null

Fossils

Coral: Thecosmilia sp., Montlivaltia sp.

Ammonoid: Paratrachyceras sp., Maclearnocerus sp.,? Lardites sp., Protrachyceras sp.


Age 

In 1979, the second area survey team in Qinghai named the Middle Triassic clastic-carbonate system in Yushu, Qinghai as the Jialong Group. In 1982, Ye Shida and Yang Tongshi divided the Middle Triassic of Yushu Jialong into the Gr (now Gelong Fm) and and the upper Benpulong Gr (now Benpulong Fm), representing the Middle Triassic Anisian and Ladinian deposits, respectively.

Age Span: 

    Beginning stage: 
Ladinian

    Fraction up in beginning stage: 
0.0

    Beginning date (Ma): 
241.46

    Ending stage: 
Ladinian

    Fraction up in the ending stage: 
1.0

    Ending date (Ma):  
237.00

Depositional setting

Shallow marine facies


Depositional pattern:  


Additional Information


Compiler:  

Zhang Shunxin, Guo Wenwei and Tong Jinnan.