Migration-based Traveltime Waveform Inversion of 2D Simple Structures: the Synclay Model
Abstract
A reformulation of the classical least-squares waveform inversion problem is proposed to retrieve the background velocity from surface seismic reflection data. To eliminate the problem of local minima, a change of unknown is performed: the depth reflectivity is replaced by a reflectivity in the time domain through a migration step. The increase in modeling complexity is the price for the enlargement of the attraction domain of the global minimum, which allows for the use of a local optimization method. A numerical implementation with a finite difference acoustic simulator is detailed. Inversion of a non-layered 2D slowness model is performed.