???????????????????о????????

由于三维地震勘探具有高密度采集、高精度以及多种灵活的显示方式等优点，因此利用三维地震资料研究地层岩性变化，预测物源方向，划分沉积体系和沉积相带，寻找砂岩发育区，评价含油气有利区块，已经是油气勘探的客观要求。本文所研究的三维地震工区位于吐哈盆地台北凹陷西部，至储层研究工作开展以前，已钻井４口，获得的油气产量甚低，结果难以令人满意。为此，以全三维地震偏移资料为基础的岩性圈闭研究得以开展。该项研究立足于三维地震工区的地质特点，结合钻井、测井等资料，利用地震微相、沉积微相、成藏条件分析等方法，确定了砂体的平面展布特征，预测了隐蔽的岩性圈闭，指出了研究区油气勘探的有利目标。

COMPREHENSIVELY UTILIZING 3-D SEISMIC DATA FOR INVESTIGATING LITHLOGICAL TRAPS

??Because the 3-D seismic exploration is of many advantages as high density acquisition,high fidelity and various flexible display modes,etc.,it has been an objective demand for oil and gas exploration to utilize the 3-D seismic data for investigating lithostratigraphic change,predicting the direction of sources,delineating sedimentary systems and sedimentary facies,seeking for sandstone-developed areas and evaluating favourable oil-and gas-bearing areas.The 3-D seismic exploration working area involved in the paper is located at the west part of Taibei depression in Tuha Basin.Before the reservoir studies were carried out,four wells had been drilled in the area,producing only little oil and gas,which couldn't be satisfied certainly.For this reason,the lithological trap investigation has been carried out on the basis of full 3-D seismic migration data.According to the geological properties of the 3-D seismic exploration working area,in combination with the drilling and logging data and by use of the methods of seismic microfacies,sedimentary microfacies and reservoir formation condition analysis etc.,the planar distribution of sandstone bodies is delineated,the subtle lithological traps are predicted and the beneficial targets for the oil and gas exploration in this area are pointed out in the paper.