Do Son Gr
Period:
Devonian
Age Interval:
Early-Middle Devonian; D1-D2 nv, (5, 6)
Province:
East Bac Bo, Vietnam Offshore North
Type Locality and Naming
Do Son Peninsula. Named by Lantenois (1907). Upward succession of largely terrigenous sediments of the coeval Van Canh Fm (seaward) and Duong Dong Fm (landward) and the overlying Van Huong Fm.
Synonym: Ngoc Vung Gr?
Lithology and Thickness
Sandstone, claystone, siltstone. See component formations.
Lithology Pattern:
Clayey sandstone
Relationships and Distribution
Lower contact
Conformable on the Kien An Fm.
Upper contact
Conformable below the Trang Kenh Fm.
Regional extent
Distributed in the Hai Phong, Quang Ninh, Hai Duong provinces and on some island in the Bai Tu Long Bay.
GeoJSON
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Fossils
See component formations.
Age
Early-Middle Devonian. See component formations.
Age Span:
Beginning stage:
Lochkovian
Fraction up in beginning stage:
0.0
Beginning date (Ma):
419.00
Ending stage:
Givetian
Fraction up in the ending stage:
0.8
Ending date (Ma):
380.18
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), with additional details from Tong-Dzuy Thanh and Vu Khuc (Editors; Stratigraphic Units of Viet Nam, 2nd edition; 2011; English edited by A. Boucot).