Figure 10

Figure 10 shows the initial gradient of the objective function with respect to the interval slowness model (taken with ). This plot is the first iteration of a tomographic back-projection of the velocity errors. This gradient gives an idea of what parts of the model have errors and how changes in those parts of the model affect the stack semblance of the data.

Figure 11

The PARTAN algorithm was run for 30 iterations and stopped when the gradient of the objective function with respect to was approximately zero. Figure 11 shows the cumulative change in the interval slowness model obtained.

1/13/1998