Supplementary Figure 1: Comparison of density models obtained from different starting models

Supplementary Figure 1A

Relative perturbations in density at six discrete depths. The density model obtained with a zero starting model is shown on the left, and the density model obtained based on a scaled S velocity model is shown on the right. Only the even-degree coefficients are shown. Blue regions denote higher than average density and red regions denote lower than average density. The scale of the maps is indicated at each depth.

Supplementary Figure 1B

Correlation between the two density models as a function of depth. The two models are almost identical, indicating that the dependence of density model upon the starting model is small.