Evaluation on petroleum exploration potential in sub-salt layers in Gabon Basin

doi:10.3969/j.issn.1672-7703.2017.05.011

Abstract

Abstract: Petroleum exploration in sub-salt layers has always been the focus all over the world. By comprehensive study on the geology of the sub-salt layers of the Gabon Basin, and analogy with the basins at the passive continental margin in South Atlantic in terms of the dynamic deformation mechanism of the lithosphere during rifting period, it indicates that the Gabon Basin is a wide rift basin with large rift development scale and petroleum exploration potential. Analysis of typical reservoir discoveries in the Gabon Basin indicates that (1) the sub-salt layers have superior petroleum geology conditions because there were abundant lacustrine source rocks during rifting period, with big hydrocarbon source potential and sufficient hydrocarbon supply; (2) the sub-salt layers have two sets (upper and lower) of reservoir-caprock assemblages, and hydrocarbons are mainly accumulated in the sandstone reservoirs in the Gamba Formation and the Dentale Formation in fluvial-delta facies in the upper assemblage, with fine reservoir properties; (3) the development of sub-salt lacustrine source rocks and the formation of traps are key factors controlling hydrocarbon accumulation in sub-salt layers in deep water regions. The comprehensive study reaches the conclusion that the sub-salt layers of the Gabon Basin have the potential of developing large-scale oil and gas fields, thus they are the target area for oversea petroleum exploration.

Key words: West African, Gabon Basin, sub-salt, rift basin, exploration potential

CLC Number:

TE122.1

Zhao Hongyan, Yu Shui, Huang Xingwen, Hao Liye, Sun Pengchao. Evaluation on petroleum exploration potential in sub-salt layers in Gabon Basin[J]. China Petroleum Exploration, 2017, 22(5): 96-101.

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