Scanning Fluorescence X-ray Microscopies (SFXM) are capable of high-spatial-resolution and high-sensitivity elemental mapping, as well as obtaining information on the chemical state of elements in the submicron range, from light to heavy elements. There appears to have the advantage of being relatively free of limitations on sample size or surface polishing, and of being easy to control the measurement atmosphere for both solids and solutions. This article introduces the principles of the analytical method, an overview of the equipment, and examples of its application to solid samples both inside and outside the Earth.

Permeability is a measure of how fluid flow occurs through rocks, which governs fluid migration in the basement rock formations. This study evaluated three-dimensional permeability and its anisotropy in the Horoman peridotite complex from geometric information of fractures using a scan line method. The results showed that the field-scale permeability ranges from 10⁻¹³ to 10⁻¹² m², with the maximum principal permeability subparallel to the layered structure of the peridotites.

Silicate liquids possess a network structure composed of corner-sharing SiO₄ tetrahedra. The fundamental process of the self-diffusion of network-forming elements remains unclear because of its network structure. This article presents several insights into the diffusion mechanism of network-forming elements by introducing the author’s previous studies with molecular dynamics simulations. Analysis of situation-wise mean square displacement reveals that diffusion via reptation occurs only in basic silicate liquids. Chemical species-wise distinct parts of van Hove’s function indicate that only non-bridging oxygen diffuses via a site-exchange manner in network-forming elements. Recently the author introduced the concept of bond forming/breaking particles. Pair-correlation functions of those particles clarified two individual bond-exchange modes for Si—O bonding. The angular part of the pair-correlation provides an atomistic description of two individual bond-exchange modes. One mode represents the bond exchange in sliding manner, while the other corresponds to the bond exchange in oscillating mode. The pair-correlation functions of bond forming/breaking particles are applicable to quantitative analysis of bond-exchange events in other condensed materials.