A new coupled spectral element and modal solution method for global seismology: A first application to the scattering induced by a plume-like anomaly

Abstract : The possibilities of a new numerical simulation method based on the coupling of the Spectral Element Method (SEM) with a modal solution method are illustrated by experiments focusing on the scattering induced by a localized plume-like inclusion in a modified PREM. The plume is represented by a vertical cylindrical inclusion extending from the surface to the 660 km discontinuity. We present seismograms computed down to 50 s and assess the limits of a first order mode perturbation (Born approximation) method against the new numerical simulation.