Migration Velocity Analysis with a second-order Gauss-Newton scheme: a 2D real data example
R. Soubaras and B. Gratacos
Event name: 80th EAGE Conference & Exhibition 2018 Workshop Programme
Session: WS01: Seismic Imaging with Ray and Waves - Where do we stand? Part I: Velocity Estimation
Publication date: 10 June 2018
Info: Abstract, PDF ( 79.37Kb )
We present the application of a Migration Velocity Analysis with a second-order Gauss-Newton update scheme (Soubaras and Gratacos (2017)) on a real 2D dataset. This second order scheme includes a deconvolution of the gradient by the Hessian, which removes the “gradient artefacts” on the velocity gradient and produces an extended reflectivity which is a least-squares migration rather than a migration. Starting with a crude initial velocity model (linear gradient from the water bottom) and leaving the velocity unconstrained, we obtained a detailed velocity model which is consistent with the geology, as well as flattened gathers.