Image-space wave-equation tomography in the generalized source domain

Image-space wave-equation tomography in the generalized source domain

Yaxun Tang, Claudio Guerra, and Biondo Biondi

Abstract:

We extend the theory of image-space wave-equation tomography to the generalized source domain, where a smaller number of synthesized shot gathers are generated either by data-space phase encoding or image-space phase encoding. We demonstrate how to evaluate the wave-equation forward tomographic operator and its adjoint in this new domain. We compare the gradients of the tomography objective functional obtained using both data-space and image-space encoded gathers with that obtained using the original shot gathers. We show that with those encoded shot gathers we can obtain a gradient similar to that computed in the original shot-profile domain, but at lower computational cost. The saving in cost is important for putting this theory into practical applications. We illustrate our examples on a simple model with Gaussian anomalies in the subsurface.

Image-space wave-equation tomography in the generalized source domain