Spin and valence dependence of iron partitioning in Earth's deep mantle.

摘要: Abstract We performed laser-heated diamond anvil cell experiments combined with state-of-the-art electron microanalysis (focused ion beam and aberration-corrected transmission microscopy) to study the distribution valence of iron in Earth’s lower mantle as a function depth composition. Our data reconcile apparently discrepant existing dataset, by clarifying effects spin (high/low) (ferrous/ferric) states on partitioning deep mantle. In aluminum-bearing compositions relevant mantle, concentration silicates drops above 70 GPa before increasing up 110 minimum at 85 GPa; it then dramatically postperovskite stability field 116 GPa. This compositional variation should strengthen lowermost between 1,800 km 2,000 depth, weaken D” layer. The succession layers could dynamically decouple from provide rheological basis for stabilization nonentrainment large low-shear-velocity provinces below that depth.