利津洼陷异常高压带及其内部成藏规律研究

利津洼陷下第三系普遍发育异常高压,对油气成藏具有重要意义。本文利用声波测井资料,运用等效深度法对利津洼陷下第三系的地层压力进行了研究,并探讨了异常高压形成机制。异常高压带纵向上发育在沙三上下部-沙四上,平面上沿洼陷长轴分布在洼陷中心,向洼陷边缘压力变小,靠近断层压力降低。控制异常高压形成的因素主要有欠压实作用、黏土矿物脱水、烃类生成及水热增压。异常高压带内剩余压力低值区油气富集,发育多种油藏类型。剩余压力低值区为下步勘探方向。

THE RESEARCH ON THE ABNORMAL PRESSURE AND RESERVOIR FORMING RULES IN LIJIN DEPRESSION

Abnormal pressure is widespread developed in Eogene in Lijin depression,which has important meaning for the reservoir forming.The strata pressure in Lijin depression has been studied by making use of acoustic logging data in this paper and the forming mechanism of abnormal high pressure has been discussed.Abnormal pressure develop between the bottom of the upper of the third member of Shahejie formation and the upper of the forth member of Shahejie formation and distribute at center along the major axis of the depression.The pressure diminishes from center to margin of the depression and depress near the fault.The factors that control the development of the abnormal pressure are uncompaction,clay mineral dewatering,hydrocarbon forming and aquathermal pressure boost.The hydrocarbon concentrates at the area of low value of residual pressure in abnormal pressure zone in which many types of reservoir develop.The area of low value of residual pressure in abnormal pressure zone is the exploration direction.