Velocity Analysis by Snell Trace Deformation and Stolt Imaging in Snell Midpoint Coordinates
, by Alfonso Gonzalez-Serrano
In a stratified earth Snell Midpoint Coordinates are a suitable fram to put seismic data before velocity estimation. Main advantages are that we can image the data and estimate velocity exactly. Imaging is costly because it requires a phase shift method to handle a v(z), the data field will be quasi-hyperbolic, imaging could then be done using an Stolt algorithm and reduce its cost. The process can be applied iteratively to converge to the correct velocity function. In practice two or three iterations should suffice.
STANFORD