A method for estimating apparent displacement vectors from time-lapse seismic images

Reliable estimates of vertical, inline and crossline components of apparent displacements
in time-lapse seismic images are difficult to obtain for two reasons.
First, features in 3-D seismic images tend to be locally planar, and components
of displacement within the planes of such features are poorly resolved. Second,
searching directly for peaks in 3-D cross-correlations is less robust, more
complicated, and computationally more costly than searching for peaks of 1-D
cross-correlations.
We estimate all three components of displacement with a process designed to
mitigate these two problems. We address the first problem by computing for
each image sample a local phase-correlation instead of a local cross-correlation.
We address the second problem with a cyclic sequence of searches for peaks
of correlations computed for lags constrained to one of the three axes of our
images.