An optimized approach to compute traveltimes in 3D unstructured meshes

Abstract

© 2018 SEG. We present an optimized method to calculate traveltimes for seismic inversion. It is a hybrid version of the shortest path approach. The main improvements consist in computing traveltimes using the seismic ray paths and using temporary secondary nodes in vicinity of the source. The proposed method is done following two sequential steps. In the first step, traveltimes are computed for all nodes using the modified shortest path method. Ray paths are then traced back for all source-receiver couples and traveltimes for each receiver are updated using nodes along the ray path. Tests have shown that this approach can improve the accuracy by an order of magnitude and save up to a third of the computation time when compared to the standard shortest path algorithm.