辽东湾北部地层压力预测及生压机制分析

为研究辽东湾北部深部地层压力状况，选择资料丰富、可靠性较高的4条主测线和3条联络测线，运用Filippone(1979，1982)的经验公式预测凹陷深部的压力特征，代表性选择了剩余压力和剩余压力系数作等值线图，并作双程反射时间在1．5～3．5s的水平切片图来说明地层压力特征，得出辽东湾北部大致分为：辽西凹陷超压区，辽西低凸起超压区和辽中凹陷超压区．确定辽东湾北部异常高压流体属于半封闭型，它与Hunt(1990)提出的异常高压流体仓具有不同的压力剖面．生压机制推测是欠压实作用、成岩作用、成烃增压、深部热流体进入等。

Prediction of the Formation Pressure in the Northern Part of Liaodong Bay Basin and Analysis on the Pressure Forming Mechanism

To study the formation pressure condition of deep-seated strata of the northern part of Liaodong Bay Basin, a prediction is made on the pressure by using four main seismic lines, three contact seismic lines in the study area and empirical formula of Fillippone(1979,1982).The formation pressure and surplus formation pressure coefficent contour profiles are selected along the lines and formation pressure horizontal slice maps from 1.5 to 3.5 seconds of two-way travel time.The abnormal formation pressure distribution in the northern part of Liaodong Bay Basin can be grossly divided into three areas:Liaozhong Depression, Low Liaozhong Bulge and Liaoxi Depression over-pressured area.The formation pressure structures of the three areas are different from those of abnormally pressured fluid compartments presented by Hunt(1990),and belong to the type of half-sealed pressure compartment.Prediction of pressure forming mechanism in the northern part of Liaodong Bay is subcompaction,diagenesis,hydrocarbon forming and deep thermal fluid.