Title
Shear Wave Tomography Beneath the United States Using a Joint Inversion of Surface and Body Waves
Document Type
Article
Abstract
Resolving both crustal and shallow-mantle heterogeneity, which is needed to study processes in and fluxes between crust and mantle, is still a challenge for seismic tomography. Body wave data can constrain deep features but often produce vertical smearing in the crust and upper mantle; in contrast, surface wave data can provide good vertical resolution of lithospheric structure but may lack lateral resolution and are less sensitive to the deeper Earth. These two data types are usually treated and inverted separately, and tomographic models therefore do not, in general, benefit from the complementary nature of sampling by body and surface waves. As a pragmatic alternative to full waveform inversions, we formulate linear equations for teleseismic S wave traveltimes and surface wave phase velocities and solve them simultaneously for variations in shear wave speed anomalies in the crust and upper mantle. We apply this technique to data from USArray and permanent seismic networks and present a model of seismic shear wave speed anomalies beneath the continental United States. Our joint model fits the individual data sets almost as well as separate inversions but provides a better explanation of the combined data set. It is generally consistent with previous models but shows improvements over both body wave-only and surface wave-only tomography and can lead to refinements in interpretation of features on the scale of the lithosphere and mantle transition zone.
Disciplines
Environmental Sciences | Geology
Recommended Citation
Golos, E. M., Fang, H., Yao, H., Zhang, H., Burdick, S., Vernon F., Schaeffer, A., Lebedev, S., van der Hilst, R. D. (2018). Shear Wave Tomography Beneath the United States Using a Joint Inversion of Surface and Body Waves. Journal of Geophysics Research: Solid Earth, 123(6), 5169-89. https://doi.org/10.1029/2017JB014894
Comments
© 2018 The Authors. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License (CC BY-NC-ND, http://creativecommons.org/licenses/by-nc-nd/4.0/), which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.