LUNAR VOLCANIC GAS CLOUD EVOLUTION: CONSTRAINTS FROM GLASS BEAD SURFACE SUBLIMATES

This repository hosts the SEM, TEM, APT, and NanoSIMS data collected from the surface mineral deposits on pristine glass beads from Apollo drive tube 74001,431. The deposits are predominantly micromound structures made of nanopolycrystalline sphalerite ((Zn,Fe)S), with iron enrichment at the bead-micromound interface. Thermochemical modelling was then performed using HSC Chemistry. This modelling indicates that hydrogen and sulfur were major elements within the volcanic plume, and ties the iron gradient to decreasing gas pressure during deposition.