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Trang Khanh Gr
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Trang Khanh Gr base reconstruction

Trang Khanh Gr

Period: 
Devonian, Carboniferous

Age Interval: 
Givetian to early Visean, (2, 3, 8, 9, 10)


Province: 
West Bac Bo, East Bac Bo

Type Locality and Naming

Upward sequence of the Bang Ca Fm, Toc Tat Fm, and two formations of the same age (Long Nam Fm in East Bac Bo, or Da Nieng Fm in West Bac Bo). Named by Tong Duy Thanh, 2000.


Lithology and Thickness

Marl with cherty shale (Bang Ca Fm), Limestone (Toc Tat Fm), Siliceous limestone (Da Nieng Fm)


Lithology Pattern: 
Limestone


Relationships and Distribution

Lower contact

Conformably upon the Ban Pap Gr (West Bac Bo) or the Na Quan Fm (East Bac Bo)

Upper contact

Conformable below the grey to light grey, thick-bedded limestone of the overlying Da Mai Fm (= Bac Son Fm).

Regional extent

In East Bac Bo it occurs in the Trung Khanh District (Cao Bang Province), and in the Dong Van Plateau (Ha Giang Province). In West Bac Bo, it is exposed in narrow bands in the lower course of the Da River (in the Van Yen area, Son La Province.


GeoJSON

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Fossils

See component formations


Age 

Givetian to mid-Visean

Age Span: 

    Beginning stage: 
Givetian

    Fraction up in beginning stage: 
0.5

    Beginning date (Ma): 
382.10

    Ending stage: 
Visean

    Fraction up in the ending stage: 
0.5

    Ending date (Ma):  
338.54

Depositional setting


Depositional pattern:  


Additional Information


Compiler:  

Tran Van Tri and Vu Khuc (Editors; Geology and Earth Resources of Viet Nam, General Dept. of Geology and Minerals of Viet Nam; completed in Dec., 2011)