26 Global Waveform Tomography with the Spectral Element Method: A Second-Generation Upper-Mantle Model
نویسندگان
چکیده
The SEMum model of Lekic and Romanowicz (2011) (SEMum v.1) was the first global VS model obtained using spectral-element forward modeling (SEM: Komatitsch and Vilotte, 1998), and exhibits impressive amplitudes of heterogeneity in the upper 200km of the mantle compared to previous global models. Among other measures to make SEM-based modeling tractable, SEMum v.1 was developed using an homogenized crustal model of uniform 60km thickness (Capdeville and Marigo, 2007). While this choice is justifiable in the continents, it can potentially frustrate interpretation of shallow uppermantle structure in the oceans. Here, we present an update to SEMum (SEMum v.2: French et al., 2011), which was obtained using an homogenized crust with more realistic laterally-varying thickness.
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