The goal of dip estimation is to find a local stepout,
, that destroys the local plane wave such that,
where u is the wavefield at time and offset h.
For all gathers, we evaluate the slope with
a method based on high-order plane-wave destructor filters
Fomel (2002). With the Z transform notation,
Fomel (2002) shows that there is a 2-D filter
that annihilates the local plane wave. The number of
coefficients for the filter Bn is n. The filter coefficients
are functions of
as detailed in equations (9) and (10) of
For instance, if n=3, we have
In equation (11), is unknown and is estimated
with a non-linear solver.