Near-surface Q Estimation from Surface Waves and Compensation for its Effects on Body Waves
D. Boiero, F. Garofalo and P.L. Vermeer
Event name: 77th EAGE Conference and Exhibition 2015
Session: Static Corrections and Near Surface Characterization from Body and Surface Waves
Publication date: 01 June 2015
Info: Extended abstract, PDF ( 1.64Mb )
Price: € 20
The near-surface weathering zone is typically made up of dissipative and low-velocity materials. This strongly affects the propagation of body waves, not only perturbing traveltimes (statics), but also reducing amplitude and altering phase through absorption. Building a reliable near-surface model in terms of visco-elastic properties can allow a better understanding of the perturbations occurring in the near surface and provide opportunities for their correction during data processing. Since surface-wave propagation is sensitive to the properties of shallow layers, surface-wave energy can be analysed and inverted for near-surface model building. In this work, we describe a method that uses surface-wave analysis and inversion to estimate P- and S-wave velocities and quality factors. We use the obtained visco-elastic near-surface model to compensate body waves according to a surface-consistent inverse-Q filtering scheme.