Last Layers of Terrestrial Magma Ocean Solidification
• Magma ocean solidifies from the bottom up
• Last 0.3% of mantle not solidified by model
• Leftover “exotic” mix of oxides in melt
– CaO (50%), FeO (27%), Al2O3 (20%), SiO2
(3%), MgO (1%)
– Enriched in Nd, Sm, U, Th too!
• What happens to the leftover material?A. Springmann, 12.470, May 14 2009
Exotic Oxide Solidification
• Create a melt with appropriate composition
• Use multi-anvil press (Takahashi 1993)
to conduct melting experiments
– X-ray mapping to determine stable
mineral phases of resulting solid
compositions
– Mass spectrometry to measure
incompatible element concentrations
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Bigger Questions
• What solidifies out of this melt?
– Apatite, magnetite, crustal perovskite, post-perovskite,
hematite, corundum, uranium oxides, or something
else?
– Densities?
– Incompatible element enrichment?
• D” layer implications
– Match incompatible element predictions from Carlson &
Boyet (2008)?
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QuickTime™ and aTIFF (Uncompressed) decompressor
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QuickTime™ and aTIFF (Uncompressed) decompressor
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