(Joint work with David Yingst) Conventional full waveform inversion (FWI) has been extensively applied to real seismic data and has successfully generated high-fidelity earth models for better seismic imaging and structural interpretation. Considering the nonlinearity and illposedness of the problem for conventional FWI, the success in providing reliable updated models heavily relies on the accuracy of the initial models and low frequency contents in the acquired data.
To relax the requirements of good initial models and adequate low frequencies, we propose a novel approach to time domain reconstructed full waveform inversion with the extended source (RFWI). RFWI relaxes the constraint that the forward modeled data exactly solve the wave equation as in conventional FWI, and instead uses an L2 approximate solution. RFWI estimates earth models and jointly reconstructs an extended source by minimizing an objective function that penalizes the wave equation error while fitting the data. RFWI extends the solution space and therefore overcomes some of the problems with local minima that prevent conventional FWI from obtaining a reliable solution with an inaccurate starting model and/or insufficient low-frequency data .