Europe-Mediterranean tomography: High correlation between new seismic data and independent geophysical observables

Abstract

To improve the fidelity of European tomographic images, we implement variable resolution parameterization, finite-frequency and ray theory, and improved data coverage in new tomographic inversions. We supplement an existing high-quality database of global teleseismic phase velocity observations of both Love and Rayleigh waves with a set of new phase delay observations recorded by a dense array of stations in the region. We invert these data to find global phase velocity maps, characterized by a more densely parameterized Europe and Mediterranean. We compare our seismic images with laterally variable independent geophysical observables, including crustal thickness, gravity, and heat flow and find correlations between 0.25 and 0.6. While at most periods finite-frequency and ray-theory yield almost coincident results, we find some possibly significant differences in the phase velocity of 150s Rayleigh waves. Our results represent significant progress toward high-resolution modeling of upper mantle S-velocity structure with the possibility of also constraining seismic anisotropy. Copyright 2008 by the American Geophysical Union.