What is IFOS3D?

IFOS3D (Inversion of Full Observed Seismograms) is a 3D elastic full-waveform inversion code.
The inversion problem is solved by a conjugate-gradient method and the gradients are computed in the frequency domain with the adjoint method.
The forward modeling is done by a time-domain finite-difference scheme.

IFOS3D is the reverse (inverse) of our 3D finite-difference forward-solver SOFI3D.