塔里木盆地牙哈断块潜山带控储控藏机理与油气勘探潜力

Reservoir controlling mechanism and hydrocarbon exploration potential of buriedhill belt in Yaha fault block,Tarim Basin

塔里木盆地牙哈潜山构造带断裂解释不精细、控储控藏机理不明确、资源潜力不清楚是制约勘探突破与产能建设的瓶颈问题。综合利用三维逆时偏移处理新资料、储层反演、岩心观察、薄片鉴定以及试油分析等方法,对牙哈潜山构造带的地层与岩相展布、潜山构造形态与断裂系统、优质储层形成机理与油气成藏过程进行了研究。研究表明,牙哈大断裂早期强烈逆冲推覆是断块潜山遭受剥蚀改造、影响储层发育与油气富集的重要地质事件。古生界发育不同类型白云岩,为内幕储层的形成奠定了物质基础,构造裂缝对岩溶型储层的发育具有积极的影响,优质储层沿断裂展布。油气源对比表明,牙哈断裂北侧油气来源于库车坳陷的三叠系—侏罗系陆相烃源岩,沿不整合面向南运移;牙哈断裂南侧油气来源于下古生界海相烃源岩,沿断裂垂向运移并在潜山面横向调整。牙哈断裂构造带为大型断块潜山复合油气藏,其重新评价突破了上寒武统背斜潜山控藏的观点,拓展了震旦系和寒武系断块潜山的勘探领域,明确了牙哈潜山构造带2 000万吨级油气勘探潜力,对潜山油气勘探开发具有重要的指导作用。

The lack of fine fault interpretation,unclear controlling reservoir mechanism and resource potential of Yaha buried-hill belt in Tarim Basin were the bottlenecks restricting exploration breakthrough and capacity construction.Using the new data of three-dimensional inverse time migration processing,reservoir inversion,core observation,thin section analysis and well testing,strata and lithofacies distribution were determined,structural morphology and fault system were characterized,the genetic mechanism and hydrocarbon accumulation of quality reservoirs were studied in Yaha buried-hill belt.The study showed that the early strong thrusting of Yaha fault was an important geological event that had affected the denudation of the fault block,the reservoir development and hydrocarbon enrichment.Different types of dolomite developed in Paleozoic laid the material foundation for the formation of insider reservoirs.Tectonic cracks had a positive influence on the development of karst reservoirs,and high-quality reservoirs spread along fractures.The comparison of hydrocarbon sources showed that hydrocarbon on the north side of the Yaha fault is mainly from the Triassic-Jurassic terrestrial hydrocarbon source rock in Kuche depression,and it moves southwards along the unconformity surface.On the south side,hydrocarbon originated from the source rock in the Lower Paleozoic,migrated vertically along the fault and adjusted laterally on the buried-hill surface.A large complex hydrocarbon reservoir model of fault-block buried-hill was created to reevaluated and broke through the view that reservoirs were controlled by the Upper Cambrian anticline buried-hill,to expand the exploration fields of Sinian and Cambrian fault-block buried-hill,and to clarify the potential of 20 million tons hydrocarbon exploration in Yaha buried-hill structural belt.It played an important guiding role in the hydrocarbon exploration and development of buried-hill.