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The phenomena of reactive percolation of enriched asthenospheric melts and pervasive melt-rock interactions at mid oceanic ridge-rift systems are the principal proponents for mantle refertilization and compositional heterogeneity. This study presents new mineralogical and geochemical data for the abyssal peridotites exposed along the Vema and Vityaz fracture zones of the Central Indian Ridge (CIR) to address factors contributing to the chemical heterogeneity of CIR mantle. Cr-spinel (Cr#: 0.37-0.59) chemistry classifies these rocks as alpine-type peridotites and corroborates a transitional depleted MORB type to enriched, SSZ-related arc-type magma composition. HFSE and REE geochemistry further attests to an enriched intraoceanic forearc mantle affinity. The distinct boninitic signature of these rocks reflected by LREE>MREE

We report the chemical composition of 176 glass spherules obtained from Antarctica blue ice and deep-sea sediments from the Central Indian Ocean Basin. This study compares the chemistry of glass spherules collected from various reservoirs, thereby allowing us to look into possible bias and efficiency of different collection techniques. Glass spherules have experienced extreme heating among the S-type cosmic spherules, and have suffered significant ablative elemental loss for which their precursors remain ambiguous. The previous model calculation for the glass spherules indicates chemical changes due to atmospheric entry. In addition, the earlier heating experiment results for the glass spherules show some insight into their formation processes. We report Ca–Al glass spherules that have high CaO+Al2O3 >9 wt% indicating larger particles with excessive evaporation of moderately volatiles (Fe, Si, Mg) resulting in refractory (Ca, Al) enriched glass or equilibration of minor Ca and Al phases in glass. Glass spherules from Antarctica and deep-sea are morphologically distinct and happen to have ablated most of their elemental Fe during atmospheric entry, however despite it, their bulk chemical composition and atomic ratios indicate to have a broad correspondence with carbonaceous chondrites, thereby, preserving the precursor properties.

A series of glycidyl methacrylate (GMA)-ethylene dimethacrylate (EGDM) copolymers of varying compositions were synthesized by free-radically triggered thermal frontal polymerization (FP) as well as by suspension polymerization (SP) using azobisisobutyronitrile [AIBN] as initiator. The two sets of copolymers were characterized by IR spectroscopy and mercury intrusion porosimetry, for determination of epoxy number and specific surface area. Frontal polymerization was more efficient, yielding greater conversions at much shorter reaction times. The self-propagating frontal polymerization also generates microporous material with narrow pore size distribution. It yields higher internal pore volume and surface area than suspension polymerization, surface morphologies are, however, inferior.