Least-squares migration with dip-field regularization: application to 3D VSP data

Least-squares migration purports to mitigate the impact of irregular acquisition geometries and limited aperture. These are both common problems with multi-offset VSP surveys, so it makes sense that a least-squares approach should be beneficial to VSP imaging. While iterative leastsquares migration implementations are expensive for 3D surface seismic data volumes, even comparatively large 3DVSP surveys are small enough to consider a full, iterative least-squares migration.