塔里木盆地巴楚地区油气运移的控制因素分析

影响巴楚地区油气运移的因素有断裂、不整合面及输导层.断裂是油气进行垂向运移的主要通道,而不整合面和输导层是油气进行侧向运移的主要通道.断裂的3次形成期为加里东期、华力西晚期和喜山期.后两期断裂规模较大、组合样式以背冲式为主,对油气的垂向运移、聚集成藏起到重要作用.3期较大的不整合面有T74界面、T70界面和T60界面.不整合面与上下地层之间存在3种接触关系:平行接触、削截接触和超覆接触,其中超覆接触关系具有最强大的输导能力.输导层有石炭系和志留系底部的连通砂体及下奥陶统顶部的岩溶.巴楚地区3次构造运动决定3次油气成藏,华力西晚期和喜山期的构造运动对加里东期形成的油气藏进行调整形成现今的油气分布格局.

Controlling Factors of Hydrlcarbon Migration in Bachu Area of Tarim Basin

The factors that affect hydrocarbon migration are fault, carrier bed and unconformity in Bachu area. Fault is the main pathway of oil-gas migration in the vertical direction, and unconformity and carrier bed are the main ones of oil-gas migration in the parallel direction. Faults formed in the Caledonian stage, the Late Hercynian Stage and the Himalayas Stage. The scale of the fault of the Late Hercynian Stage and the Himalayas one is more biggish, and the main combination is the thrust. The two latter play important roles in the vertical migration, and accumulation of the oil-gas. The three main unconformities are T74 boundary, T70 one and T60 one. The relation of unconformity with around beds is parallel one, truncation one and overlap one. The overlap one has the best migration ability. Carrier bed includes the sandstone in the bottom of Carbonifeous-siburian system and the karst in the top of the lower Ordovician system. Three times structure movements decided three times hydrocarbon accumulation in Bachu area, and the oil-gas formed in the Caledonian Stage was adjusted by the structure movements in the Late Hercynian Stage and the Himalayas Stage, then formed the distribution of the oil-gas nowadays.