Incorporation of Multiples for Migration Velocity Analysis with VSP Data

We demonstrate the original method for the migration velocity analysis with VSP data. The method is based on the use of surface-related multiples jointly with the primary reflected data for the VSP imaging. Velocity updates are carried out by matching the images obtained by using different types of waves. To do it automatically we introduce a cross-correlation type objective function and develop a maximization algorithm based on the adjoint-state method. We show that maximization of the cross-correlation of the images built on different types of waves allows to retrieve the velocity parameters. At the same time the refinement of the velocity model could lead to significant improvements of the seismic images.