Radial anisotropy in the European mantle: Tomographic studies explored in terms of mantle flow
نویسندگان
چکیده
[1] Previous studies have shown that radial seismic anisotropy as estimated from flow models is in good agreement with results from tomography at global scale, in particular underlying oceanic basins. However, the fit is typically poor at smaller scale lengths, particularly in tectonically complex regions. We conduct a comparative analysis of tomographically mapped and dynamically modeled radial anisotropy at the scale of Europe and the Mediterranean Basin, including three tomographic models based on different observations and/or methods. We find that adaptive-grid surface-wave tomography, with parametrization density depending locally on the spatial and azimuthal density of data coverage, leads to the seismic model closest to (albeit still far from) geodynamic predictions. The ability to map regional-scale seismic anisotropy may provide a new constraint, complementary to isotropic tomography, to the nature of upper mantle flow. Citation: Schaefer, J. F., L. Boschi, T. W. Becker, and E. Kissling (2011), Radial anisotropy in the European mantle: Tomographic studies explored in terms of mantle flow, Geophys. Res. Lett., 38, L23304, doi:10.1029/2011GL049687.
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