Zongcai Feng, PhD Student at Kign Abddullah U. of Science and Tech., presents "Elastic Least-squares Reverse Time Migration: a Gradient-based Iterative Method and a Deblurring Filter Approach".
"Elastic least-squares reverse time migration (LSRTM) inverts for the P- and S-reflectivity images based on the linearized elastic-wave equations. Two approaches are proposed for implementing elastic LSRTM: a gradient-based iterative method and a deblurring filter approach which approximates the Hessian inverse. Numerical tests on these two approaches show that the elastic LSRTM images have better resolution, more balanced amplitude, fewer artifacts, and less crosstalk compared with the elastic reverse time migration (RTM) images. The advantage of the deblurring filter is that it gives the image with similar quality compared to the gradient-based iterative method, but with a computational cost that is an order of magnitude cheaper."