川西坳陷油气资源现状及勘探潜力

川西坳陷经历了十分复杂的演化历史,一方面形成了丰富的油气资源,另一方面也导致了油气在空间的分布不够集中,这些特点决定了川西坳陷的勘探工作具有长期性和艰巨性。川西坳陷成藏动力学系统研究表明:虽然该区油气规模运移聚集发生在储层致密化之前,但圈闭的形成定型时期较晚,因此,具多源、多期成藏的复合含油气系统特征决定了该领域立体成群的气藏分布格局。根据川西坳陷资源特点和着眼大目标、立足大发现的勘探方针,近中期勘探工作的重点是:主攻深层,扩大中深层,拓展外围浅层。

STATUS OF OIL & GAS RESOURCES AND PROSPECTING POTENTIAL IN WESTERN IN SICHUAN DEPRESSION

The western Sichuan depression has experienced very complicated evolution.As a result,it is characterized by vertically stacking of various basin types,multiple styles of trap strucuture,multiple source and resevoir rocks, and multiple superimpositions and reconstructions.Although abundant petroleum resources have been generated, the special distribution of oil and gas is under-concentrated.Systematic study of dynamics of hydrocarbon reservoiring indicates that there might have been late reservoiring condition in this area, and major migration and accumulation of oil & gas might have occurred before the reservoirs to be tightened.Forming phase of trap is crucial to trap validity,and the features of composite petroleum system control the distribution pattern of gas reservoirs to be three-dimensionally in groups.According to the characteristics of hydrocarbon resources in western Sichuan depression and aiming at the large prospecting targets,main objects of near and medium term exploration plans should be focused on deep gas reservoirs,expanding exploration of moderate deep gas reservoirs and extending the periphery shallow gas reservoirs.