Solidus of Earth's deep mantle
The solidus of a pyrolite-like composition, approximating that of the lower mantle, was measured up to 59 gigapascals by using CO2 laser heating in a diamond anvil cell. The solidus temperatures are at least 700 kelvin below the melting temperatures of magnesiowustite, which in the deep mantle has the lowest melting temperatures of the three major components-magnesiowustite, Mg-Si-perovskite, and Ca-Si-perovskite. The solidus in the deep mantle is more than 1500 kelvin above the average present-day geotherm, but at the core-mantle boundary it is near the core temperature. Thus, partial melting of the mantle is possible at the core-mantle boundary.
Zerr
A
A. Zerr and R. Boehler, Max-Planck-Institut fur Chemie, Postfach 3060, 55020 Mainz, Germany. A. Diegeler, Institut fur Mineralogie und Geochemie der Universitat zu Koln, 50674 Koln, Germany.
Diegeler
A
Boehler
R