Full Wavefield Modeling with Vector Reflectivity

This work describes a method for computing the full acoustic seismic wavefield using a new two-way equation parameterized by vector reflectivity and velocity. This method is contrasted with full wavefield modeling using variable density and demonstrates the equivalence of the two methods. Thus, if an estimate of reflectivity is known or estimated the full acoustic seismic wavefield can be generated from velocity and reflectivity without explicit knowledge of density. This has an impact in any seismic inversion procedure such as Full Waveform Inversion. A modeling example is shown demonstrating the equivalence of the two methods for a known earth model. Wavefield snapshots and seismograms for both methods are shown including the cases of the following: (1) total vector reflectivity, (2) the vertical and horizontal components of reflectivity separately and (3) variable density. A second example compares recorded field data to synthetic seismograms obtained with the proposed approach, where the estimated reflectivity was extracted from a seismic image. It is noted that data misfits between the real and modeled data could be used in velocity and reflectivity inversion.