This Major Research Instrumentation (MRI) award funds the acquisition of a state-of-the-art new electron microprobe, a key tool for research and training used by a broad spectrum of researchers and students. Electron probe microanalysis (EPMA) is an analytical technique that allows researchers across multiple disciplines to collect information on chemical composition, phase identification, morphologies, spatial relations, and trace element characteristics of both natural and synthetic solid materials at the micron scale. The new instrument will replace an existing NSF MRI-funded EPMA (Award# 9413900) that has served as the key geochemical instrument at the New Mexico Bureau of Geology and Mineral Resources (NMBG) at New Mexico Tech (NMT) for the past 27 years. The new EPMA will significantly enhance analytical capabilities at NMT, meeting the needs of a diverse research community and advancing the training of the next generation of geoscientists in electron microscopy. <br/> <br/>The Field-Emission EPMA will provide the highest resolution imaging available, enhancing phase and morphological analysis. The advanced imaging technology will be complemented by five wavelength-dispersive spectrometers and an energy-dispersive spectrometer, improving detection limits and enabling more precise chemical determinations. Additionally, a panchromatic cathodoluminescence detector will be included to resolve complex minor and trace-element zoning features, providing insights into paragenetic sequences that other imaging techniques cannot achieve. The new instrument will significantly advance the research capabilities of NMT faculty and research scientists across a diverse range of topics, including natural and experimental volcanic glass, mineralogy, economic geology, crustal evolution and tectonics, petrology and volcanology, environmental contamination, ice core and climate.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.