Computation of multivalued traveltimes in three-dimensional heterogeneous media

Abstract

In this thesis, I propose several methods for an efficient computation of 2D and 3D traveltimes of transmitted waves in smooth media. Traveltimes are needed in several seismic processing methods such as Kirchhoff prestack and poststack migration, migration velocity analysis, Kirchhoff modelling, or traveltime tomography. The greatest number of traveltimes are needed by 3D prestack Kirchhoff depth migration (PKDM). Despite the continuous increase in computing capacities, the computation of traveltimes for 3D PKDM is still a challenge. Since the wavefront is usually folded, the same wave may arrive at a subsurface point more than one time, i.e., we have multivalued traveltimes...