| With an area of 100 square kilometers, the Xianhe 3D seismic survey is geographically located at the Liaodong Gulf, Bohai Sea, and geologically at the down-block of the Hainan Fl fault, eastern margin of west-depression, Liaohe Basin. There are 2 exploratory wells in the area, Shi-1 and LH-11-1, among which, oil and gas shows were found in the at the 1st, 2nd and 3rd intervals of Shahejie Formation, Lower Tertiary in Shi-1 well.Studies show that the occurrence of reservoirs and the reliability of traps are the dominated factors for the further exploration of oil and gas in the area. Therefore, this paper focused on the prediction of reservoirs by using seismic inversion and the prognostication of formation pressure by applying PCD method.Seismic inversion results indicate that the delta sandstone reservoirs occurred extensively in the 2nd and 3rd intervals of Dongying Formation, Lower Tertiary, and become poor only to the western margin of the survey area. In contrast, the fan delta sandstones in Shahejie Formation developed mainly in the area between Fl and F2 faults, and turbidity sandstones locally in the rest of the survey area.Pressure prediction results demonstrated that the 1st and 2nd intervals of Shahejie Formation are generally over-pressured. The author believes that the pressure data can be served as an important parameter for the evaluation of seal-property of faults. Different faults, even different parts of same fault do have different seal-properties. Generally, the sealing property of same faults becomes well downward from the Dongying Fm to Shahejie Formation. Fl, F2, F3 are well sealed faults, F4, F6 and F7 are partly well-sealed faults, and the F5 is the poor-sealed fault, relatively and specifically.Therefore, we can conclude from the predictions of reservoirs and pressure in the area that the major exploration prospects should be the reservoirs between the Fl and F2 faults and the turbidity fan sandstones in the down-block of F2 fault.
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