An error and stability analysis of four nonstationary wavefield extrapolators

Robert James Ferguson, Gary F. Margrave

An error and stability analysis is presented for the elementary nonstationary wavefield extrapolators LN+, LP+ and their symmetric hybrids LA+ and LPN+ . The analysis is based on analytic expressions that describe the inversion of wavefields extrapolated by the four operators. Our analysis shows that LA+ and LPN+ are more accurate and more stable than elementary extrapolators LN+ and LP+.

The Marmousi synthetic data is used to provide a comparison of depth imaging using the different extrapolators. The largest mean absolute amplitudes of the resulting depth images corresponding to LN+ (~1000) and LP+ (~1000) indicate that recursive application of these extrapolators caused growth in the extrapolated wavefield. The mean absolute amplitudes of LA+ (~800) and LPN+ (~800) were an order of magnitude less indicating greater stability. The best image of the model was returned by the LA+ method.