Full-waveform inversion for full-wavefield imaging: Decades in the making

Seismic imaging using full-wavefield data that includes primary reflections, transmitted waves, and their multiples, has been the holy grail for generations of geophysicists. To be able to use the full-wavefield data effectively requires a forward modeling process to generate full-wavefield data, an inversion scheme to minimize the difference between modeled and recorded data, and more importantly, an accurate velocity model to correctly propagate and collapse energy of different wave modes.