I generated two synthetic data sets assuming an earth model that includes
two flat layers with constant elastic properties on each layer.
In model 1, I chose the same elastic properties for both the overlaying and
the underlying layer, which results in no AVA effect along the interface.
In model 2, I chose rock properties corresponding to velocity
and density contrast in the underlying layer which leads to an AVA
effect of decreasing amplitudes with increasing angle on incidence.
Figure 1 shows the expected *P*-wave reflection
coefficient corresponding to model 1 and model 2, calculated using Zoeppritz equations.

Figure 1

The modeling was done using a ray tracing approach to get the timing of the event and using the exact Zoeppritz equations to set the amplitude values. Figure 2 shows the picked amplitudes for the resulting modeled data.

Figure 2

4/29/2001