塔里木盆地顺北超深断溶体油藏特征与启示

近年来,塔里木盆地顺托果勒低隆起发现了10亿吨级的新类型油藏——顺北超深断溶体油藏。通过深化顺北地区油气成藏地质条件认识,突破了构造低部位岩溶储层欠发育的限制,提出走滑断裂带构造破裂作用为主的叠加后期埋藏流体改造也可形成规模储层。走滑断裂带多期活动对储层改造、圈闭形成和油气运聚具有重要的控制作用,建立了顺北超深断溶体油气藏“寒武纪多期供烃、深埋断溶成储、原地垂向输导、晚期成藏为主、走滑断裂控富”成藏模式,初步提出了顺北断溶体油藏富集的主控因素。顺北超深断溶体油藏作为一种新类型油藏,丰富了海相碳酸盐岩油气成藏理论,展现了超深层海相碳酸盐岩巨大的勘探潜力,是盆地未来油气增储的重点领域。

Characteristics and inspiration of ultra-deep fault-karst reservoir in the Shunbei area of the Tarim Basin

In recent years,a new type of oil reservoir,ultra-deep fault-karst oil reservoir,has been discovered with reserves of 1 billion tons in the low uplift of Shuntogole in the Shunbei area in Tarim Basin.By deepening understandings of geological conditions of oil and gas accumulation in the Shunbei area,breakthrough has been made to the knowledge that karst reservoirs were not developed in the lower structure positions.And it is proposed that large-scale reservoirs can also be formed by later superimposed buried fluid reformation on the main structure fracturing of the strike slip fault zone.The multi-stage activities of strike slip fault zone play an important role in controlling reservoir reformation,trap formation and hydrocarbon migration and accumulation.Hydrocarbon accumulation mode of"multi-stage hydrocarbon supply from Cambrian,deep buried fault-karst as reservoir,in-situ vertical migration,mainly late stage accumulation,strike slip faults controlling the enrichment"has been established for ultra-deep fault-karst reservoir in the Shunbei area.The main controlling factors for hydrocarbon enrichment in fault-karst reservoir in the Shunbei area have been identified.As a new type of reservoir,ultra-deep fault-karst reservoir in the Shunbei area extended the theory of hydrocarbon accumulation in marine carbonates,shows a great exploration potential of ultra-deep marine carbonate formations,and is an important field for reserve increase in the future.