四川盆地加里东古隆起震旦系气藏成藏控制因素

CONTROLLING FACTORS OF SINIAN GAS POOLS IN CALEDONIAN PALEOUPLIFT,SICHUAN BASIN

四川盆地加里东古隆起的形成演化具有长期性和复杂性 ,使得古隆起震旦系的天然气成藏有早有晚。早期成藏主要发生在印支期 ;晚期成藏主要发生在喜山期。每期成藏可以划分出 3种不同的成藏类型 :即高捕集高阻抗、高捕集低阻抗及低捕集。天然气藏的主要控制因素为“两高一强一关联” ,即较高的封存能力、较高的构造部位、较强的构造形变 ,晚期形成的圈闭与古油气藏具有密切关联。

The formation and evolution of Caledonian paleo-uplift in Sichuan Basin possessed long-term and complicacy.This resulted in different pool-forming stages of Sinian natural gas of the uplift.The early stage of pool-forming occured in Indo-Chinese Epoch;the late stage was in Himalayan Epoch.Each pool-forming stage could be divided into three types i.e.high entrapment with high resistance,high entrapment with low resistance and low entrapment.The main controlling factors of Sinian gas pools in Caledonian paleo-uplift are high sealling capability,high position of the structure;strong tectonic deformation and a close interconnection between the late-stage formed traps and the paleo-reservoirs.