VSP Kirchhoff Migration with Structure Constraint

Existing VSP Kirchhoff migration technique is combined with the structure dip information reduced from a newly developed structure tensor analysis (Jin et al., 2014) to improve image quality and allow for imaging dip structures away from the borehole. The HESS salt model is used to validate the improved VSP imaging results. The synthetic waveform data computed from the HESS model are migrated using the structure constrained Kirchhoff migration. The sub-salt structures and, especially, a dipping fault away from the borehole are clearly imaged. The image result is comparable to RTM but greatly improved from the conventional Kirchhoff migration method.