Prestack migration using seismic interferometry

탄성파 간섭파를 이용한 중합전 구조보정

Prestack depth migration is used to image for complex geological structure such as faults, folds, and subsalt. In this case, it is widely used the surface reflection data as a input data. However, the surface reflection data have intrinsic problems to image the subsalt and the salt flank due to the complex wavefields and multiples which come from overburden. For overcoming the structural defect of the surface reflection data in the imaging, I used the virtual sources in terms of seismic interferometry to image the subsurface and suppress the multiples using the velocity model of the lower part of the virtual sources. The results of the prestack depth migration using virtual source gathers and velocity model below receivers are similar geological interfaces to the results from shot gathers of the conventional ocean bottom seismic survey. And especially artificial interfaces by multiples were suppressed without applying any other data processing to eliminate multiples. This study results by numerical modeling can make a valuable imaging tool when it is applied to satisfied field data for specific condition.