Abstract

The Common Focus Point (CFP) method is used for migration velocity analysis in the prestack domain. It is based on the principle of equal traveltime, i.e. for a correct model, the time-reversed focusing operator has exactly the same traveltime as the corresponding CFP response for all offsets. Any deviation from zero differential time shift (DTS) indicates incorrect model parameters which need to be updated. This method has been used for macro model estimation in hetergogeneous isotropic media. However, the assumption of isotropy may be incorrect in complex geological settings where anisotropy may be significant causing erroneous results. Here we extend the CFP method to account for homogeneous anisotropy in the wavefield extrapolators. The effect of erroneous anisotropic parameters on DTS panels is easily observable. We map the differential time shifts to derive anisotropy parameters in a homogeneous transversely isotropic media with a vertical axis of symmetry.