DEPTH-IMAGING RESOLUTION OF 3-D SEISMIC RECORDING PATTERNS

The prestack imaging resolution capabilities of various 3-D seismic re cording patterns are revealed when a Born-approximate theory is applie d to backscattered waves. The 3-D imaging resolution of such patterns is compactly studied using a constant-velocity model with a point scat terer or a line scatterer at depth. By use of a well-known acoustic im aging formula, it is shown that the resolution of a point scatterer in the X and Y directions is not significantly different for various rea listic layouts of sources and receivers in land-type recording, even t hough the recording patterns appear to be greatly dissimilar, provided the aperture remains constant. For marine-type survey patterns, the i mage is almost as well-resolved in the crossline direction as the inli ne direction. This is true whether the scattering object is a point or a line. In marine surveying, symmetric resolution of subsurface featu res can be achieved by conducting two orthogonal surveys at half the d ensity of one unidirectional survey.