Melting experiments on peridotite to lowermost mantle conditions

Near-solidus Melting of the Shallow Upper Mantle: Partial Melting Experiments on Depleted Peridotite

We present the results of melting experiments on a moderately depleted peridotite composition (DMM1) at 10 kbar and 1250±1390 C. Specially designed experiments demonstrate that liquids extracted into aggregates of vitreous carbon spheres maintained chemical contact with the bulk charge down to melt fractions of 0 02±0 04 and approached equilibrium closely. With increasing melt fraction, SiO2, F...

Melting of peridotite to 140 gigapascals.

Interrogating physical processes that occur within the lowermost mantle is a key to understanding Earth's evolution and present-day inner composition. Among such processes, partial melting has been proposed to explain mantle regions with ultralow seismic velocities near the core-mantle boundary, but experimental validation at the appropriate temperature and pressure regimes remains challenging....

Calculating melting temperatures and pressures of peridotite protoliths: Implications for the origin of cratonic mantle

Metasomatism and Partial Melting in Upper-Mantle Peridotite Xenoliths from the Lashaine Volcano, Northern Tanzania

REE (LREE) into the glass with respect to clinopyroxene, but the A group of chrome-spinel peridotite upper-mantle xenoliths from the reverse for Sr and Y, in both mica-bearing and mica-free parageneses. Lashaine volcano, northern Tanzania, differs from other xenoliths In a mica-bearing melt pocket, Rb and Ba partition preferentially at this locality in containing glassy melt pockets. Modal, min...

Variable azimuthal anisotropy in Earth's lowermost mantle.

A persistent reversal in the expected polarity of the initiation of vertically polarized shear waves that graze the D'' layer (the layer at the boundary between the outer core and the lower mantle of Earth) in some regions starts at the arrival time of horizontally polarized shear waves. Full waveform modeling of the split shear waves for paths beneath the Caribbean requires azimuthal anisotrop...