This Major Research Instrumentation (MRI) Program award will acquire a multi-collector inductively coupled plasma mass spectrometer (MC-ICP-MS) for the Department of Geological Sciences at the University of Texas at El Paso (UTEP). This instrument will be used to measure the isotopic ratios of important elements in rock, environmental, and biological samples, and will build on the pioneering isotopic research of three early-career faculty members. Specific research initiatives include: 1) The application of stable isotopes to unravel the key geochemical, hydrological, and magmatic processes that control the local and global distributions of elements like Cu, Fe, Zn, Cr, and Se , 2) The application of Cu, Fe, and Zn isotopes to probe chemical reactions that span the interface between biology and geology (for example, the uptake of metals into cells), 3) The application of radiogenic isotopes to understand the geologic history of Earth, and 4) The application of the isotopes of elements like Zn, Cl, Cr, and Pb to fingerprint contaminant sources and track them in the environment. The MC-ICP-MS will additionally support research in the areas of environmental sciences, medical sciences, anthropology, and forensics. This instrument provides UTEP, the only research intensive doctoral university in the United States with a Mexican-American majority student population, with a state-of-the-art facility for advanced isotopic research. The success of student training and education initiatives depends heavily on the type and quality of research experiences we can offer. The acquisition of this instrument greatly enhances these training and educational opportunities and will foster student and faculty development. The management plan for the MC-ICP-MS will develop synergies among student training (at both the undergraduate and graduate level), faculty development, and research excellence.