摘要 |
The present invention relates generally to a method for migrating prestack seismic data that can yield enormous gains in computational efficiency for some classes of seismic velocity models. The methods disclosed herein provides a method of rapidly calculatinga 2-D or 3-D prestack migration of common offset seismic data volumes for horizontally layered velocity models. Additionally, because of the way that the migration is implemented, it is possible to calculate the migration operator using a very accurate wave transmission model with little increase in overall computer run time, i.e., a "full fidelity" migration. Broadly speaking, the instant invention is founded on the following novel observation: when the underlying velocity model consists of horizontally layered constant-velocity media, the prestack migration of a collection of common offset traces can be written as a convolution of a migration operator with the seismic data. As such, the migration may be sped up enormously by transforming both the migration operator and the seismic data to another domain where the convolution between the two can be calculated very efficiently. The invention disclosed herein will be most fully appreciated by those in the seismic interpretation and seismic processing arts.
|