The role of source modeling in prestack depth migration for AVO estimation

Saúl Ernesto Guevara, Gary F. Margrave

A progress report on the true amplitude migration issue for AVO is presented here. Synthetic seismic data are generated using elastic Finite Difference modeling, and PreStack Depth Migration is carried out on these data using the PSPI approach. Angle gathers of the migrated data are generated, and its amplitude versus angle relationship is compared to the theoretical amplitudes from the Zoeppritz equations. The source is modeled using a 2-D Green’s function solution. Characteristics of the migrated data for PP and PS wave modes, including postcritical events, are analyzed. Some explanations are proposed and issues for future research in this topic are raised.