Synchrotron X-ray diffraction hints at presence of magma ocean deep underground

A geoscientists group at the European Synchrotron Radiation Facility (ESRF, Grenoble, France), has recently found that a natural fertile peridotite, which is a characteristic material of the Earth's mantle, can be partially molten at a pressure of 140 GPa, when the temperature reaches 4,200 K. This could reinforce the hypothesis of the presence of a deep magma ocean. The experiments showed that the liquid produced during this partial fusion is dense and that it can hold multiple chemical elements, among which are important markers of the dynamics of the mantle. For more information, see the paper, "Melting of Peridotite to 140 Gigapascals", G. Fiquet et al., Science, 329, 1516 (2010).