Unconstrained direct Dix-type inversion in a layered VTI medium

摘要

In standard Dix equations, developed for a stack of homogeneous horizontal layers with VTI symmetry, the traveltime parameters estimated from PP and PS reflections are used to compute the interval traveltime parameters. These interval traveltime parameters can be converted into the model parameters for each layer. A drawback of the standard inversion technique is its instability in estimated model parameters which require involving constraints in the inversion. I propose a method for the unconstrained direct Dix-type inversion of PP and PS reflection traveltimes into the model parameters. The method is based on the average of parameter estimates computed for each horizontal slowness or propagation angle.