Seismic Prediction Of Deep Marine Carbonate Reservoir In Longmenshan Foreland Basin

Great potential gas resources exist in Longmenshan foreland basin，yet its explorationlevel remains low,which is mainly related to the characteristics of carbonate reservoirs. Themarine carbonate reservoir buries deep and shows an obvious heterogeneity and multipletypes of reservoirs. However, its distribution and development are also controlled by variousfactors. These factors make it more difficult to reservoir prediction and assessments. It has notcome up with a set of effective methods to predict reservoirs in Longmenshan foreland basinmarine carbonate, which is a serious obstacle to the further development of the oil and gasexploration in western Sichuan. The target of the thesis is the deep marine carbonate reservoirprediction in Longmenshan foreland basin with the combined applications of the geophysical,logging and geologic methods. The main contents and results are shown as follows:During this research, firstly the relationship of the logging and seismic responsecharacteristics is connected through the well logging data. Secondly, five wells syntheticseismograms are conducted, which means that geological stratums are corresponding to seismiclayers. Particularly, the five wells are the Longshen1Well, Chuanke1well,Xinshen1wells,Xiaoshen1wells and the Chuanhe100wells. After that, seven geological horizons ofTT3m、 TT2l2、 TT2j4、 TT1j2、 TT1f4、 T p2、 Tp1are successfully tracked. Then, underjoint control of the five logging data and seven layers in the region, the model of the velocityfield is established in the district. Next, converting time domain to the geological depth domainand the depth structural maps of the seven geological layers are completed. Finally, with thecompletion of detailed structural interpretation, distributions of geological structure andfracture system in Longmenshan foreland basin are concluded.With the research on many seismic prediction technologies, some effective techniques, such as coherent analytical techniques, curvature attributes, ant tracking technology,high-resolution spectral decomposition techniques, well-phased high resolution post-stackinversion and some amplitude attribute extraction are chosen in the paper. This research isbased on the results of the technology above to collaboratively forecast the distribution of thereservoir and geophysical characteristics. After the study on the reservoir geophysical responsecharacteristics and mode, the conclusion is that the potential reservoir located in the south ofMajing town, east of Xinchang town and south of Wenxing town. Consequently, this studyeffectively predicts the location of reservoir and evaluates the favorable objective. Besides, atechnique of predicting marine carbonate reservoir in Longmenshan foreland basin is proposed.