The alternative to wave equation methods is a numerical
damping zone, as in Figure 16,
which reduces the wave strength over a grid
region near the boundary. The idea is to slowly and smoothly
apply a weight which will be
effective in the aggregate.
The product
, 
,
is computed to a small factor 
with the property of
certain smoothness at both edges.
The smoothness is required to reduce the unwanted reflections.
Figure 16: Computational Model Damping Zone.
Figure 17: Geological Model.
Figure 18: Model Boundary Damping Nodes, Left Side.
