Two-Point Ray Tracing Based on Eikonal Solvers

This paper presents two-point ray tracing algorithm in anisotropic media and in isotropic media with salt intrusions of complicated interfaces. The main peculiarity of this approach is the use of finite difference solutions of Eikonal equation. The traditional ways of two point ray tracing are shooting and bending (Peryra V., Lee W.H.K., Keller H.B., 1980). In comparison to these well-known approaches the proposed algorithm is more stable and computationally cheaper.<br>This approach is extremely effective as two point ray tracing method for specific acquisition geometries widely used for 3D Offset and Walk-away VSP. Really, for this statements a moderate number of receivers (a few tens usually) are used, so one should apply nonlinear eikonal solver for a few ten times as well. Another important advantage is the fact that time of computations does not depend on the complexity of a model.<br>In order to illustrate the range of applicability we present numerical results for anisotropic Gullfaks model and in well known Sigsbee2a model that contains salt body with very rough interface. The experiments demonstrate the approach provides stable two point ray tracing algorithm for a medium with complex geology in a presence of anisotropy layers and salt intrusions. Numerical experiments prove that the method finds a ray for any source/receiver pair in a presence of anisotropy and salt intrusions. The last property is really important in many applications.