Velocity model evaluation through Born modeling and migration: a feasibility study

Method

The goal of the procedure we will describe is to use Born modeling to synthesize a new dataset that is much smaller than the original dataset used to generate an initial migrated image. Since the synthesized data can be ``recorded'' at any location in $x$ , $y$ , and even $z$ , this procedure is effectively target-oriented. There are three basic steps needed to reach our goal of efficient velocity model evaluation:

1. Generate an areal source function using one or more subsurface offset gathers from the initial prestack image.
2. Using the new source function and a reflectivity model based on the initial image, employ Born modeling to generate a new dataset with acquisition geometry best suited to image the target area.
3. Migrate the simulated data obtained in Step 2, using the source function from Step 1. This step is extremely computationally efficient compared to a full migration of the original data, allowing for testing of several possible velocity models in a fraction of the time it would take to evaluate them using standard migration techniques.

In the following sections we detail the theoretical basis for each of these steps.

Velocity model evaluation through Born modeling and migration: a feasibility study