Abstract: Slant-Wave Stack
If all shots were fired at the same time, the downgoing wave would be a plane wave. The upcoming wave could be synthesized from conventional data by summing, with zero moveout, all shots into each geophone. Data generated by a downgoing plane wave at some nonvertical angle likewise is synthesized, using a moveout function which is linear with offset. Seismic sections thus generated, called slant-wave stacks, may be analyzed rigorously with the wave equation in contrast to common-midpoint stacked sections. Theoretically, we expect slant-wave stacks to yield velocity analysis which is less sensitive to multiple reflections than conventional velocity analysis, while providing a framework to handle problems involving lateral velocity variations within a cable spread, migratio before both velocity analysis and final stack, and diffracted deep-water multiple reflections. Theoretically, we expect slant-wave stacks to have lower signal-to-noise ratios than common-midpoint stacks but higher than single-offset sections. Experimentally we have found that the slant-wave stack often provides sharper definition than the common-midpoint stack.
AAPG Search and Discovery Article #90976©1976 AAPG-SEPM-SEG Pacific Section Meeting, San Francisco, California