Velocity estimation for seismic data exhibiting focusing-effect AVO

Ioan Vlad and Biondo Biondi

nick@sep.stanford.edu, biondo@sep.stanford.edu

ABSTRACT

Transmission anomalies sometimes create AVO effects by focusing the reflected seismic wavefields, which impedes AVO analysis. The AVO anomalies caused by focusing are distinguishable by surface consistent patterns. We analyze the previous efforts to define, describe and eliminate spurious AVO anomalies. We also propose using wave equation migration velocity analysis to build an accurate velocity model. The transmission-related AVO can then be eliminated by downward continuation through this velocity model.