Fig. 7From: Subducted oceanic crust as the origin of seismically slow lower-mantle structuresPower spectral density plots for S40RTS over 30∘ longitude across the Pacific (top row) and African (bottom row) LLSVPs. Spectral power is normalized to the maximum power at each depth and plotted as a function of wavenumber and radius. Over 30∘, the broad scale spectral characteristics of both LLSVPs is relatively consistentBack to article page