Kinematics of prestack shot-geophone migration

Prestack migration methods based on data binning produce kinematic artifacts, i.e. coherent events not corresponding to actual reflectors, in the prestack image volume, when the medium is strongly refracting. Shot-geophone (“survey sinking”) migration, on the other hand, does not produce such artifacts when events to be migrated arrive in the data along non-turning rays. In contrast to prestack migration methods based on data binning, common image gathers produced by shot-geophone migration exhibit the appropriate semblance property in either offset domain (focussing at zero offset) or angle domain (focussing at zero slope), when the migration velocity is kinematically correct. Thus shot-geophone migration may be a particularly appropriate tool for migration velocity analysis of data exhibiting structural complexity.