f 3D Surface consistent decomposition for refraction modelling: a workstation implementation

Refraction analysis, modeling, and statics, are often standard components of the production processing sequence for 3-D data volumes. Many algorithms exist to define a near surface model from the refraction analysis of 2-D and 3-D production field records. A new surface consistent decomposition algorithm has been developed and implemented on the workstation that will efficiently model the near surface based upon travel times derived from 3-D production field records. The algorithm is implemented using a conjugate gradient technique. The least squares error minimization is statistically analyzed to gain confidence in the solution. This error analysis facilitates identification of picking problems, inadequately identified refractor segments, or geometry problems. The interactive implementation allows problem areas to be identified, while iterating to the final model . Capabilities exist to interactively correct the problems before proceeding further with the modelling. This method ensures an optimal near surface model is derived in an efficient manher for 3-D data volumes, crooked lines, or 2-D data. Results of the 3-D implementation of the surface consistent decomposition algorithm on a 3- D data example will be provided .