Imaging complex near-surface land area with joint traveltime and waveform inversion

Abstract

Summary We image the near-surface seismic velocity structures in complex land area with rugged topography by applying a joint seismic traveltime and waveform inversion method. This method retains the advantages of both traveltime inversion and full waveform inversion (FWI) and overcomes their drawbacks at the same time. The joint method is independent on starting models, has no cycle skipping issues, and converges fast. We apply the method to study complex near-surface land area where shallow overthrust and rugged topography present a significant challenge for using any method alone. We test synthetic data and understand the performance of the joint method, and then apply the method to a 2-D line in Yumen oil field in China. The results and analysis suggest that the joint traveltime and waveform inversion helps to constrain the very shallow velocities and also resolve complex overthrust with large velocity contrasts.