Obtaining Low Frequencies for Full Waveform Inversion by Using Augmented Physics

Abstract

Full waveform inversion (FWI) is a process in which seismic data in the frequency or time domain are being fitted by changing the velocity of the media under investigation. The problem is nonlinear, and therefore, optimization techniques have been used to attempt and find a geological solution to the problem. The main problem in fitting the data is the lack of low special frequencies. This deficiency often leads to a local minimum and to non-geologic solutions. In this work we discuss how to obtain low frequency information that can augment FWI. We explore two techniques, the first, travel time tomography and the second, controlled-source electromagnetics. We then discuss a framework for joint inversion and show that by considering these problems jointly we are able to steer the direction of FWI towards the global minimum.