Selecting spatial samples based on seismic migration of dip formation
【Abstract】The spatial sampling interval is an important parameter for seismic data acquisition and processing. At the moment, the formula for calculating spatial sampling intervals only considers the aliasing-free samples of reflected waves, or diffracted waves in the migration aperture, but it is not suitable for the imaging requirements of dip formations. In this paper, the time-distance equation of reflected wave is established based on the essence of seismic migration imaging and the distribution characteristics of diffracted wavefield. Then the spatial sampling formula for migration imaging of dip formations is derived based on the principle of seismic wave inphase superposition, and finally, the spatial sampling of seismic imaging with different dips and frequencies is analyzed. The result provides a reliable basis of spatial sampling selection for seismic data acquisition design and migration imaging.
【Keywords】 spatial sampling; dip formation; diffracted wavefield; time-distance equation of reflected wave; in-phase stacking;
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