AAPG GEO 2010 Middle East
Geoscience Conference & Exhibition
Innovative Geoscience Solutions – Meeting Hydrocarbon Demand in Changing Times
March 7-10, 2010 – Manama, Bahrain
Scanning Anisotropy Parameters in Inhomogeneous Media
(1) Enviromental and Geosciences, KAUST, Thawul, Saudi Arabia
Parameter estimation in an inhomogeneous anisotropic medium offers many challenges, chief among them is the trade off between inhomogeneity and anisotropy. It is especially hard to estimate the nonhyperbolicity parameter η in complex media. Using perturbation theory and shanks transform, I expand the solutions of the anisotropic eikonal equation for transversely isotropic (TI) media with vertical symmetry axis (VTI) in terms of the independent parameter η in a generally inhomogeneous elliptically anisotropic medium background. This new VTI traveltime solution is based on a set of precomputed traveltimes extracted from solving a number of linear partial differential equations sequentially. These traveltimes serve as the coefficients of a Taylor-type expansion of the traveltime in terms of η. Shanks transform is used to predict the transient behavior of the expansion and improve its accuracy. A homogeneous medium simplification of the expansion provides classical nonhyperbolic moveout descriptions of the traveltime that are more accurate than other recently driven approximations. In addition, this formula provides a tool to scan for anisotropic parameters in a general inhomogeneous medium. A Marmousi test demonstrates the accuracy of this approximation.