安塞油田补偿成藏现象探讨

Probe into Compensatory Reservoir-Forming Phenomena in Ansai Oilfield

安塞油田三叠系延长组长6油层发育的区域，很少有长2、长3油层组叠加发育，而长6油层发育较差的区域，似乎是为了补偿而广泛发育诸如长2、长3乃至侏罗系油层。通过对安塞油田中生界三叠系延长组沉积特征、烃原岩发育及分布、油气运移、圈闭条件及类型进行综合研究，认为补偿成藏现象与鄂尔多斯盆地安塞油田油气运移规律和长4＋5盖层发育状况有重要关系，而长4＋5盖层发育程度是补偿成藏现象发生关键因素。补偿成藏现象对安袈油田油气勘探与开发具有重要的指导意义。

There is little overlapping development of Chang2 and Chang3 oil reservoir group in the areas where Chang6 reservoirs developed in the Triassic Yanchang Formation of Ansai Oilfield. While it seems for compensation that Chang2, Chang3, and even Jurassic reservoirs are extensively developed in the areas where Chang6 reservoirs are poorly developed [1]. Through integrative researches of sedimentary features, source rock development and distribution, oil/gas migration, trap conditions and types of Triassic Yanchang Formation of Mesozoic in Ansai oilfield, it is considered that the compensatory reservoir-forming phenomena have important relationships with the oil/gas migration law and Chang4＋5 caprock development situation of Ansai oilfield in Ordos basin. The degree of Chang4＋5 caprock development is a key factor of occurrence of the compensatory reservoir-forming phenomena. The compensatory reservoir-forming phenomena are of great significance for exploration and development of Ansai Oilfield.