Anisotropic model building with wells and horizons: Gulf of Mexico case study comparing different approaches

Anisotropic depth imaging with ver-tical transversely isotropic (VTI) models has become the dominant practice in the industry. However, anisotropic parameters for these models continue to be derived by basic practices without the use of tomography. Hanging a single profile of Thomsen's parameters from the water bottom still remains the most common practice. In a simple structural setting, it is usually possible to focus the data and obtain a good image despite having a simple and unrealistic model for Thomsen's parameters. However, depth positioning of such images is usually suboptimal. Better positioning requires more geologically plausible models. In addition, imaging in complex settings may require tilted transversely isotropic (TTI) models.