Fig. 2
From: Subducted oceanic crust as the origin of seismically slow lower-mantle structures
Plot of temperature and composition fields for Brandenburg et al. (2008) models for δ lnρ of 0% (a, b) and 3.8% (c, d), where we use the non-linear radial projection of the models onto Earth coordinates. In both cases, recently subducted oceanic crust meets the CMB and the low viscosity upper mantle has been homogenized by convective stirring relative to the lower mantle. When δ lnρ = 0%, oceanic crust is somewhat evenly distributed throughout the lower mantle. In contrast, when δ lnρ = 3.8%, oceanic crust accumulates and the CMB forms sharp piles