Electronic Thesis and Dissertation Repository


Master of Science




Pratt, R. Gerhard


I present an application of a high-resolution subsurface imaging technique known as “full-waveform inversion” (FWI) to a vibroseis seismic dataset from eastern Ohio, USA. The data were collected over a crooked line with rough topography, 3.5 km maximum offsets, and no significant frequency content below 12 Hz. These parameters present challenges to obtaining quality images from FWI. The use of a preconditioner–the ‘scaled-Sobolev preconditioner’ (SSP - Zuberi and Pratt, 2017)–on the gradient of the misfit functional was key to obtaining low wavenumbers without discarding high wavenumbers. The results represent the first successful application of FWI with the SSP to a field dataset, with a high-resolution image that generally matches the trends of the Big Injun sand and Berea sandstone layers at the survey location. The novel FWI results confirm the absence of small scale structure (including the lack of visible faults) in the first 0.66 km.