Abstract:When comparing acquisition parameters in routine seismic exploration,such as fold,bin size and so on,discussion on the influence of shot density and trace density to pre-stack imaging in high density 3D seismic acquisition design seems more important.Base on the derived relationship between shot density/trace density and bin/folds,and by comparison and analysis of pre-stack migration effects,signal to noise ratio and acquisition cost between high precision 3D geometry design in YA area and its 5 degradation designs,the following conclusions were obtained in this paper:(1).As the bandwidth of the seismic data is limited,a threshold exists for relationship curve of pre-stack effect,shot density and trace density,under the threshold the signal to noise ratio increases with the shot density and trace density,however over the threshold,the signal to noise ratio only could improve a little bit if increasing shot density and trace density.(2).For different areas and targets buried in different depth there are different thresholds,the more complicated the areas are,the bigger the thresholds will be,and the shallower the targets are,the bigger the thresholds will be.Therefore selection of the shot density and trace density in high precision 3d needs to match the structural complexity and seismic exploration bandwidth,that should be determined with priority.It will be ok if the selected bin and fold could meet the need of the shot density ant trace density.Decreasing interval of geophones or adopting single receiver acquisition and high resolution processing could expand frequency bandwidth,the two measures could raise the shot density and trace density accordingly,no need to pay much attention to the small bin and high fold so that the acquisition parameters could have bigger optimization space,the idea of designing the geometry based on the pre-stack imaging can be truly reflected.
屠世杰. 高精度三维地震勘探中的炮密度、道密度选择——YA高精度三维勘探实例[J]. 石油地球物理勘探, 2010, 45(6): 926-936.
Tu Shi-jie. Selection of shot density and trace density in high precision 3D seismic exploration-a high precision 3D exploration case in YA area. OGP, 2010, 45(6): 926-936.