Influence of Compaction Length on Radial Melt Segregation in Torsionally Deformed Partially Molten Rocks

Stress-driven melt segregation in partially molten rocks

[1] We demonstrate that deformation of partially molten ductile rocks can produce melt segregation by two-phase flow. In simple shear experiments on several melt-rock systems at high temperature and pressure, melt segregates into distinct melt-rich layers oriented 20 to the shear plane. Melt segregates in samples in which pressure gradients can develop at length scales less than the sample thic...

Microtomography of partially molten rocks: three-dimensional melt distribution in mantle peridotite.

The permeability of the upper mantle controls melt segregation beneath spreading centers. Reconciling contradictory geochemical and geophysical observations at ocean ridges requires a better understanding of transport properties in partially molten rocks. Using x-ray synchrotron microtomography, we obtained three-dimensional data on melt distribution for mantle peridotite with various melt frac...

Compaction-driven melt segregation in migmatites

A common and puzzling feature of migmatite terranes is the presence of synkinematic leucosomes oriented perpendicular to the maximum principal compressive stress axis, s1, particularly leucosomes oriented parallel to the axial plane of folds. These are parallel to planes of compaction, but experiments predict that leucosomes should form in dilational bands oriented instead at small angles to s1...

Influence of dihedral angle on the seismic velocities in partially molten rocks

Influence of contiguity on seismic velocities of partially molten aggregates

[1] The microstructure of partially molten rocks plays a key role in determining their physical properties. The area fraction of intergranular contact, contiguity, governs the establishment of a skeletal framework of solid grains and controls the effective elastic moduli of the aggregate. This work presents a theoretical calculation of steady state grain shape, contiguity, effective elastic mod...