Azimuthal seismic anisotropy constrains net rotation of the lithosphere
نویسنده
چکیده
[1] Net rotation (NR) of the lithosphere is found in hot spot reference frames, important for tectonics and plume models, but difficult to constrain. Using mantle flow and crystallographic texture modeling, I show that NRs lead to mantle shearing which is recorded in azimuthal seismic anisotropy. The NR amplitude in some hot spot models is so large that it degrades the model fit to anisotropy significantly. Smaller NRs, such as predicted by flow models with stiff continental keels, are consistent with seismology, however. Citation: Becker, T. W. (2008), Azimuthal seismic anisotropy constrains net rotation of the lithosphere, Geophys. Res. Lett., 35, L05303, doi:10.1029/ 2007GL032928.
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