东营凹陷南坡异常高压分布与油气运移

The surpressure distribution and oil-gas migration in the southern slope of Dongying Depression

东营凹陷南坡异常高压的分布与成藏关系密切,在1500m以下的埋深条件下,可以采用半对数式回归正常趋势线方程求取压实系数,再运用声波时差与地层压力的关系计算剩余压力。研究结果表明,东营凹陷南坡的异常高压在2500m左右开始产生;在平面上,地层剩余压力由洼陷中心向边缘减小,沙三段与沙四段压降特征不同,但主要压降方向均是地下油气运移的主要指向区,其中沙四段存在3个重要油气优势运移指向。

The distribution of surpressure has a close relation with pool forming in Dongying Depression. Under 1 500 meters of ground,the compaction coefficient can be calculated by the half-log-arithm normal trend equation,and the overpressure can be calcu-lated according to the relation of interval transit time and forma-tion pressure. The surpressure in the south slope in Dongying De-pression is produced at 2 500 meters underground. Laterally,the formation overpressure decreases from the central of depression to margin. Sha3 member and Sha4 member have various pressure drawdown characteristics,but their main direction of pressure drawdown indicates the favorable region of oil and gas accumula-tion. There are three important predominant oil -gas migration targets in Sha4 member.