Using Converted Wave Seismic Data To The Lithology And Hydrocarbon Potential Of The Geological Explanation

Lithologic reservoirs and fractured reservoirs are becoming more and more importantin petroleum exploration. It is more difficult to find these complex reservoirs than thestructure reservoirs by general P-wave seismic exploration. How to break the traditionaltheories and methods in geological exploration, obtain the more detailed informationabout structure, lithology, fracture and stress field from geological seismic data, themethods of converted wave seismic exploration have the obvious advantage compare withthe general P-wave seismic exploration, and have had some success with it. Based on reading amounts of papers about converted wave seismic theories andmethods, some seismic attribute parameters related to lithology and oiliness were analyzedin this thesis, and some important problems and methods of seismic data processing andinterpreting on converted wave exploration were introduced. At last, two 2D3C lines inone gas field were be instanced, horizons on three component sections were contrastedand interpreted based on the incorporation of processing and interpreting; by the methodof detailed velocity ratio analyse, the ratios of P-wave velocity and S-wave velocity of thethin horizons were obtained. By the attribute sections of velocity ratio and amplitude ratio,the lithology and oiliness were be analyzed and validated by the actual drilling data; basedon the theory of S-wave splitting in the anisotropy media, the fast S-wave was separatedfrom the slow S-wave by means of the ratio method, and the angle of the fractureorientation in igneous rock was be calculated; based on the time difference of fast S-wavefrom the slow S-wave, the fracture density was be analyzed and the results matches wellwith the regional stress. By the theory research and actual cases, some conclusions can be drawed in thisthesis: the velocity ratio of P-wave and S-wave can be related to the gas distribution areas;based on the S-wave splitting, the fast S-wave can be separated from the slow S-wave andthe anisotropy parameters can be calculated. Reference these informations, the fracturedensity and orientation can be quantificationally indicated.