摘要
对柴达木盆地尕斯断陷与苏北盆地洪泽凹陷中断层的作用进行了研究，结果表明，断层在静止状态对油气运移主要起封闭作用，在断距大于储层单层厚度以及断开层序的净毛比较小（＜０．４）的情况下，断层横向上主要起封闭油气的作用；而纵向上对油气的封闭能力与泥岩欠压实带有关，欠压实带的过剩孔隙流体压力可阻止其下方的油气沿断层向上运移，欠压实带之上的油气则可以沿断层向上运移（或渗滤），并引起油气差异聚集。
Effects of faulting on hydrocarbon migration along/across it in the Gasi faulted-depression, Qaidam Basin and the Hongzhe depression, North Jiangsu Basin have been analysed. The hydrocarbon migration across/along a fault may be obstructed when the fault is in the stillstand period. Laterally, the hydrocarbon migration across the fault isprobably restricted by clay smear, lower net-to-gross ratio (e. g. less than 0. 4) or largerthrow (more than the reservoir thickness ). Vertically, the likelihood of hydrocarbon percolation along the fault relies more on pressure sealing from undercompacted shales which can easily close the fracture openings because of their higher ductility, protecting oiland gas from upward migration. If pressure sealing not existed in a succession within which a fault has been developed, the hydrocarbon, especially its lighter composition, may migrate or percolate along the. fault, particularly at shallow depth, resulting in differential entrapments.
出处
《江汉石油学院学报》
CSCD
北大核心
1996年第1期7-13,共7页
Journal of Jianghan Petroleum Institute
关键词
断层
二次运移
油气聚集
fault
secondary migration
(net-to-gross ratio)
fault throw
(undercompacted shale)
oil and gas accumulating
