Structural Interpretation And Weathering Crust Reservoir Prediction Of The Top Of The Bedrock In Changde Region

This paper by sequence stratigraphy, structural geology and seismic reservoir prediction theory as the instruction, comprehensive analysis of the seismic and logging data of Chang DE area, carried out the research of the bedrock surface structure interpretation and reservoir prediction, and predict areas favorable.In this study, based on the synthetic seismic records, comprehence seismic reflection characteristics and multiple seismic attributes, completed the interpretation of the top of the bedrock T5 reflector combination well and seismic, and in the preparation of T0 figure, on the basis of the use of the method of variable velocity mapping, establish space velocity field, to extract the average velocity diagram, T5 reflector structure diagram canbe completed by the deep-time transformation, and a preliminary study of the study area on the structure, fault and trap features ofthe surface of the bedrock. According to the basal geodynamics environment at the same time, combining with the basin basement lithology profiles, comprehensive analysis of basal density, according to the magnetic anomalies, predict basement lithology. Songliao basin bedrock weathering crust and basement in changde area mainly consists of upper Paleozoic and Mesozoic rocks before, can be divided into phyllite, granite, four kinds of sedimentary rocks, broken granite.Seismic inversion and seismic attribute analysis technology are effective method for prediction of reservoir. on the basis of curve well pretreatment methods, such as curve normalized, by using sparse pulse post-stack seismic inversion method, P-Impedance wave Impedance inversion data volume canbe gained, and combined with root-mean-square and frequency amplitude of the bedrock surface T5 reflection, predict the bedrock weathering crust thickness. Comprehensive the above research, combining with gas source and caprock distribution, predicting the favorable areas.The research area were controlled by basement depression fracture xuxi fracture, depression in xuxi fault as the boundary, the bedrock surface presents the structure characteristics of the low east and the high west, basement lithology presents the characteristics of the zoning of east and west,and block of the north and south, the weathering crust thickness in the relative low-lying areas and below the two wings ancient weathering datum are the highest and distribute widly, which is the favorable natural gas accumulation.