Abstract
Two recent forms of velocity-density relations have been inverted using Earth models derived from free-oscillation data to infer mean atomic weight profiles for the mantle. Within present uncertainty there is no evidence for discontinuities in mean atomic weight m̅; from below the crust to just above the core-mantle boundary. The best value for a constant m̅ is 21.1 ± 0.4 g/mole. Uniform m̅ is consistent with whole-mantle convection and with diminished total iron content of the Earth. Because the mean atomic weight profiles are sensitive to small differences among the normal-mode Earth models, further refinement of these models is of great interest.
This content is PDF only. Please click on the PDF icon to access.
You do not have access to this content, please speak to your institutional administrator if you feel you should have access.