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Matlab code used to analyse Melt Volume Orientation (MVO) data as shown and described in Bader, J.A., W. Zhu, L. Montési, C. Qi, B. Cordonnier, D. Kohlstedt, & J. Warren, Effects of Stress-driven Melt Segregation on Melt Orientation, Melt Connectivity and Anisotropic Permeability, Journal of Geophysical Research: Solid Earth, DOI 10.1029/2023JB028065 

Abstract Stress‐driven melt segregation may have important geochemical and geophysical effects but remains a poorly understood process. Few constraints exist on the permeability and distribution of melt in deformed partially molten rocks. Here, we characterize the 3D melt network and resulting permeability of an experimentally deformed partially molten rock containing several melt‐rich bands based on an X‐ray microtomography data set. Melt fractions range from 0.08 to 0.28 in the ∼20‐μm‐thick melt‐rich bands, and from 0.02 to 0.07 in the intervening ∼30‐μm‐thick regions. We simulated melt flow through subvolumes extracted from the reconstructed rock at five length scales ranging from the grain scale (3 μm) to the minimum length required to fully encompass two melt‐rich bands (64 μm). At grain scale, few subvolumes contain interconnected melt, and permeability is isotropic. As the length scale increases, more subvolumes contain melt that is interconnected parallel to the melt bands, but connectivity diminishes in the direction perpendicular to them. Even if melt is connected in all directions, permeability is lower perpendicular to the bands, in agreement with the elongation of melt pockets. Permeability parallel to the bands is proportional to melt fraction to the power of an exponent that increases from ∼2 to 5 with increasing length scale. The permeability in directions parallel to the bands is comparable to that for an isotropic partially molten rock. However, no flow is possible perpendicular to the bands over distances similar to the band spacing. Melt connectivity limits sample scale melt flow to the plane of the melt‐rich bands. 

Image data of sample QC0705, with analysis scripts and derived data 

Abstract Factors driving freshwater salinization syndrome (FSS) influence the severity of impacts and chances for recovery. We hypothesize that spread of FSS across ecosystems is a function of interactions among five state factors:human activities,geology,flowpaths,climate, andtime. (1)Human activitiesdrive pulsed or chronic inputs of salt ions and mobilization of chemical contaminants. (2)Geologydrives rates of erosion, weathering, ion exchange, and acidification‐alkalinization. (3)Flowpathsdrive salinization and contaminant mobilization along hydrologic cycles. (4)Climatedrives rising water temperatures, salt stress, and evaporative concentration of ions and saltwater intrusion. (5)Timeinfluences consequences, thresholds, and potentials for ecosystem recovery. We hypothesize that state factors advance FSS in distinct stages, which eventually contribute to failures in systems‐level functions (supporting drinking water, crops, biodiversity, infrastructure, etc.). We present future research directions for protecting freshwaters at risk based on five state factors and stages from diagnosis to prognosis to cure.