加蓬盆地盐岩特征及其对盐下油气勘探的影响

加蓬盆地是一个典型的被动大陆边缘含盐盆地，以下白垩统盐岩为界分为盐上、盐下两个勘探领域。近年来随着巴西深水盐下陆续获得多个世界级油气田发现，以加蓬、宽扎为代表的西非盐下也逐渐成为世界油气勘探的热点。如何落实盐下圈闭是制约盐下油气勘探的首要难题。从盐岩岩性组合、岩石物理特征入手，分析了加蓬盐岩特征及其对盐下地震成像及构造落实的影响。同时，针对加蓬深水这一热点区域勘探程度低、烃源岩、储层等基本石油地质条件不清的特点，利用盆地模拟手段，分析了加蓬深水区盐下烃源岩的热成熟度及盐岩对盐下烃源岩热演化的影响;结合新钻井资料，分析了盐岩对盐下储层物性的影响，指出加蓬深水区盐下储层具有较好物性;分析了盐岩平面分布特征，从盖层角度指出了盐下油气勘探最有利的区带。对其他含盐盆地盐下油气勘探具有一定借鉴意义。

Gabon Basin Salt Characters and Its Influences on Pre-salt Oil and Gas Exploration

Gabon Basin is a typical Atlantic passive margin salt basin, which is subdivided into pre-salt sequence and post-salt sequence by Aptian salt. Inspired by several giant pre-salt discoveries, such as Tupi, Franco, Libra in Brazil deep water, West Africa salt basins such as Gabon, Kwanza have attracted eyes from world major players in recent years. In order to solve pre-salt trap identification difficulties, we analyzed the lithological and petrophysical characters of Gabon salt and its influences on pre-salt imaging and seismic interpretation. Meanwhile, pre-salt in deep water Gabon is less-explored and thus pre-salt source and reservoirs characteristics are not clear. Considering heat conductivity, density and ductility character of salt, we analyzed pre-salt source rock maturity in Gabon deep water and salt influences on pre-salt source rock maturity based on basin modeling; we analyzed salt influences on pre-salt reservoir quality and pointed out deep water Gabon developed high quality pre-salt reservoirs by using new well data; we analyzed salt distribution, deformation and its influences on hydrocarbon charge and preservation, and pointed out that favorable pre-salt exploration areas and favorable areas for post-salt accumulations from pre-salt source. This paper may have some inspiration for other salt basin exploration.