Research On Fine Three Dimensional Seismic Exploration Technique In Complex Structure Zone Of Qinglongtai

With the development of prospecting and exploitation of oil and gas, the oil and gas exploitation become more difficult in Liaohe Oil Field. Today, the ancient 3D seismic data cannot satisfy the exploration requirement of the deep layers, complicated fault and other hidden oil reservoir. Since 2000, Fine 3D seismic exploration has been developed in Liaohe Oil Field. Through improving seismic acquisition technology and updating the equipments, we made such a great progress in the quality of seismic data. After processing and interpretation, we discovered many favorable traps. From the former exploring and exploitation information, we know that Qinglongtai zone is worth exploiting, but the quality of seismic data is very bad, especially the deep layer. Most traps locate in complicated rift zone, volcanic area, deeper layer and bad surface condition's area. It is significant to improve the band of frequency and the ratio of signal and noise in this area's exploration.According to the quality index of acquisition, we analyzed Qinglongtai's seismic and geological conditions firstly. Then we find out the main reasons which affect quality index through the analysis of the well logging data and old seismic data. Aim at the difficulties of acquisition in the target area, we conducted the technical research which include the fine surface layer survey, high precision topography survey, optimum source parameters and geometry design of complicated structure, pre-stack depth migration processing. At last we work out an optimal method: the exploding in fine sand, under the low velocity layer 4-5 meters. According to different geological structure, we adopted different seismic acquisition geometry and well number shooting method. Through the application of new technology, we have improved the quality of seismic data. The form of structure and fault are clear, the ratio of signal and noise is higher on the new seismic section. The main frequency is improved about 30 Hz. We realized the researching purpose.