王家岗断阶带含烃流体的成藏效应分析

王家岗断阶带及其附近地区地层和地层流体所表现出的能量场和物质两方面的成藏效应,反映其局部地区的油气运移具有瞬态流体流动的特点.在以断层活动为主、以烃源岩超压为辅的双重控制作用下,来自牛庄洼陷内深部烃源岩的超压含烃热流体沿断阶带内的断层向王家岗地区方向快速充注.能量场上,快速的大规模流体流动既引起了地温场的局部扰动,也将深层的超压能量传递到浅层.物质上,溶解有大量矿物质的深部热流体以混相涌流的方式运移到浅层.流体活动强的断层附近区域水-岩相互作用强烈,地层岩石中的碳酸盐质量分数和黏土矿物组成变化较大.同时在深部流体进入浅层活动活跃的层段内,地层水矿化度高的地段聚集的油气也较多.

Analysis of the Petroleum Accumulation Effects in Wangjiagang Fault Zone

The petroleum accumulation effects of both energy and material from formation and formation fluid in Wangjiagang fault zone all around showing petroleum migration in some local areas is characterized by transient fluid flow. The hot overpressured hydrocarbon-bearing fluid from source rocks in Niuzhuang Sag is rapidly injected toward Wangjiagang area through the fault zone, controlled primarily by faulting and secondary by overpressure in source rocks. While the rapid fluid flow of large scale not only brings the unbalance of geothermal field locally,but also transmits overpressure energy from the deep formation to the lower. While the fluid in miscible-phase carries a great amount of dissolved minerals to the lower formation. Where the fluid-flow is active near faults,with intensive water-rock interaction,there is a wide variation of both carbonate content and composition of clay minerals, and the water salinity is evidently much higher with more petroleum accumulation than elsewhere.