陆相断陷盆地岩性油气藏成藏过程物理模拟及机理初探

摘要

As the hotspot and emphasis of petroleum exploration, lithologic reservoir is the main type of subtle reservoirs for increasing reserves in continental rifted basin, but there are many differences of cognition in the aspect of migration process and hydrocarbon mechanism. According to the hydrocarbon accumulation characteristics of lithologic reservoirs in continental rifted basin, the physical simulation on hydrocarbon accumulation process was carried out, and the accumulation mechanism of lithologic reservoirs was studied. The result shows that lithologic reservoirs have differences in accumulation process, accumulation characteristics and accumulation efficiency under different conditions. The episodic accumulation has high accumulation efficiency and high speed characteristics. Hydrocarbon source conditions, charging patterns, pressure, faults, sand bodies properties are the main controlling factors of lithologic reservoir accumulation. Among these conditions, fault connected migration pathway is the critical factor of lithologic reservoir forming. The research results may have important significance for research of hydrocarbon accumulation mechanism of lithologic reservoirs in continental rifted basin.%岩性油气藏是我国东部陆相断陷盆地油气储量增长的主体,但目前对其成藏过程和机理的认识还存在较大分歧。文中根据断陷盆地岩性油气藏成藏特征,针对性地建立了岩性圈闭模型,对其油气运聚成藏过程进行了物理模拟并深入研究了其成藏机理。结果表明：在不同条件下,岩性油气藏在成藏过程、成藏特征、成藏效率等方面均存在差异;幕式成藏具有成藏效率高、速度快的特征,油气源条件、充注方式、充注压力、断层断穿及砂体自身物性是岩性油气藏成藏的主要控制因素,其中是否有断层断穿的运移通道是岩性油气藏成藏的关键。该研究结果对于断裂发育的陆相断陷盆地岩性油气藏成藏机理的研究具有重要意义。