加蓬LT2000区块盐下构造特征与勘探方向分析

加蓬LT2000区块是中石化在南加蓬次盆中的一个重要的勘探区块,该区位于早期大陆边缘裂谷盆地和晚期被动大陆边缘盆地叠合地区,构造条件复杂,有盐上和盐下两套含油气系统,油气成藏规律不明确。采用板块构造理论,盆地分析和构造分析的方法,明确盐下油气系统是区块主要的勘探层系;盐下划分为两个构造层,具有不同的构造特征;从盐下构造结构特点和圈闭发育程度进行评价,区块北部是盐下油气成藏最有利的地区,应该是区块油气勘探的主要方向。

Analysis on Sub-salt Structural Characteristics and Exploration Direction of Block LT2000 in Gabon

The Block LT2000 was one of the important blocks for SINOPEC overseas oil exploration in South Gabon Subbasin.The block was located in the superimposed area between the early continental margin rift basin and the late passive continental margin basin and had complicated structural conditions which resulted in two petroliferous systems of the subsalt and the above-salt.The hydrocarbon accumulation rules were still unclear.By using the methods of plate tectonic theory,basin analysis and structural analysis,it is clarified that the subsalt petroliferous system is the principle exploration strata in the block and it is divided into two structural layers with different structural characteristics.For the assessment of the subsalt structural configuration and trap development degree,north part of the block is the most favorable area for hydrocarbon accumulation and should be the major petroleum exploration direction.