Thermal expansion measurements at very high pressure, systematics, and a case for a chemically homogeneous mantle

摘要: New data on thermal expansivity, α, of iron to over 400 kbar in laser- and electrically-heated diamond anvil cells MgO forsterite from spectroscopic 200 previously measured adiabats [Boehler, 1982], imply that α at high pressure may be described by a constant value (∂1nα/∂1nV)T = 5.5 ± 0.5. This behavior is supported previous measurements lower pressures large variety materials. Densities magnesio-wustite silicate perovskite pyrolitic ratio calculated mantle conditions using finite strain equation pressures, the above systematics, match those PREM through entire mantle, making strong case for uniform mantle.