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川西前陆盆地沉积厚度大,烃源丰富,圈闭多,保存条件良好,具备形成大中型气田的成藏条件,勘探潜力巨大,是四川盆地内重要的天然气勘探接替领域。但同时川西又是一个构造条件及成藏机制较为复杂,具有一定勘探风险的地区。通过天然气成藏地质条件和典型气藏剖析,认为天然气成藏主要控制因素:一是储渗条件较好的储层(包括裂缝相对发育区); 二是规模较大、形成较早的古圈闭,并以此两条件有机配置的地区为最好。天然气运移距离短,运聚总体上与异常压力流体封存箱密切相关。根据构造地质特征、成藏条件及资源潜力对川西地区天然气勘探前景进行了分析,提出下步勘探有利区带为龙门山推覆体前缘断褶构造带、米仓山前缘断褶构追带、梓潼凹陷和龙泉山断褶构造带。
The western Sichuan foreland basin is characterized by large sedimentary thickness, rich hydrocarbon source, abundant traps and good preservation conditions, which have the conditions of forming reservoirs for large and medium-sized gas fields and have great potential for exploration and are important areas for exploration and replacement of natural gas in the Sichuan Basin. At the same time, however, the western Sichuan is also a tectonic setting and reservoir forming mechanism is more complex, with some exploration risk areas. According to the geological conditions of gas reservoirs and the analysis of typical gas reservoirs, it is considered that the main controlling factors of natural gas accumulation are as follows: first, reservoirs with relatively good conditions of reservoir permeability and permeability (including the relative development zones of fractures); secondly, large- Closed, and the two conditions of the organic configuration of the region as the best. Natural gas migration distance is short, transport and aggregation are generally closely related to the abnormal pressure fluid tank. Based on the tectonic geology, reservoir forming conditions and resource potentials, the prospects of natural gas exploration in western Sichuan are analyzed. The favorable exploration zone in the next step is the front fault fold belt of Longmen Shan nappe, the front of Micangshan fault fold chaser Belt, Zitong sag and Longquanshan fold fold belt.