Seismic AVO and the inverse Hessian in precritical reflection full waveform inversion

A projected Hessian for full waveform inversion

A Hessian matrix in full waveform inversion (FWI) is difficult to compute directly because of high computational cost and an especially large memory requirement. Therefore, Newton-like methods are rarely feasible in realistic largesize FWI problems. We modify the BFGS method to use a projected Hessian matrix that reduces both the computational cost and memory required, thereby making a quasiNew...

A projected Hessian matrix for full waveform inversion

A Hessian matrix in full waveform inversion (FWI) is difficult to compute directly because of high computational cost and an especially large memory requirement. Therefore, Newton-like methods are rarely feasible in realistic large-size FWI problems. We modify the quasi-Newton BFGS method to use a projected Hessian matrix that reduces both the computational cost and memory required, thereby mak...

Full waveform inversion of reflection seismic data for ocean temperature profiles

[i] We show that ocean temperature profiles can be accurately recovered using only acoustic methods employed at the sea surface. Using a towed air gun array and a hydrophone streamer, thermohaline boundaries are ensonified at a suite of frequencies and angles, yielding travel time trajectories and reflectivities. These data are inverted via full waveform inversion to estimate sound speed and, s...

Pre-stack full waveform inversion of ultra-high-frequency marine seismic reflection data

An integrated inversion of seismic refraction and reflection data using combined wave-equation tomography and full waveform inversion

We have developed an integrated method to obtain highresolution subsurface elastic parameters using combined wave equation tomography (WET) and full waveform inversion (FWI). Both refraction and reflection data are used. During parameterization, long wavelength and short wavelength structures are separated and mapped into velocity and density to account for kinematics and dynamics, respectively...