Nam Con Son Fm

Period:

Neogene

Age Interval:

Late Miocene; N₁³, (31)

Province:
Vietnam Offshore south

Type Locality and Naming

Nam Con Son Basin. The type section is located in Dua-IX, at a depth of 1868 to 2170 m (N = 7°36’; E = 109°5’).

Synonym: Hệ tầng Nam Côn Sơn: Lê Văn Cự 1982; Đỗ Bạt 1985, 1993, 2001. Hệ tầng Cửu Long: Ngô Thường San 1982.

Lithology and Thickness

White-grey, fine-grained sandstone interbedded with carbonate-bearing siltstone, claystone and limestone; these sediments contain abundant marine fauna (mainly foraminifera). The thickness of the formation in this borehole is 302 m.

Lithology Pattern:

Fine-grained sandstone

Relationships and Distribution

Lower contact

Unconformably upon the Thong - Mang Cau Fm

Upper contact

Unconformably under the Bien Dong Fm

Regional extent

Nam Con Son Basin.

GeoJSON

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Fossils

Globigerinoides ruber, Gds. obliquus, Gds. immaturus, Globorotalia dutertrei, Gl. acostaensis, Sphaeroidinella dehiscens, Sph. subdehiscens and Globorotalia dehiscens

Age

Late Miocene.

Age Span:

Beginning stage:

Tortonian

Fraction up in beginning stage:

0.0

Beginning date (Ma):

11.63

Ending stage:

Messinian

Fraction up in the ending stage:

1.0

Ending date (Ma):

5.34

Depositional setting

It is interpreted as a

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), with additional details from Tong-Dzuy Thanh and Vu Khuc (Editors; Stratigraphic Units of Viet Nam, 2^nd edition; 2011; English edited by A. Boucot).