EA: Replacement of a Powder X-ray Diffractometer for Teaching and Geoscience Research at Appalachian State University

X-ray diffraction (XRD) is a common technique in geoscience to identify and characterize earth materials. This project will acquire a modern X-ray diffractometer that is accessible for undergraduate students. This replacement instrument will support four faculty researchers, their student research teams, and seven classes across two departments.

Employment trends of alumni show that XRD is essential to a variety of industries, including materials science, industrial health, and environmental site assessments. The new diffractometer will contribute to Next Generation Science Standards modules and other outreach materials, where middle and high school students use real-world data to generate materials appropriate for different teaching objectives spanning Earth sciences to chemistry to math, from grades 6-12.

The renewed XRD capability at Appalachian State University will support faculty and student research projects that span a variety of geoscience disciplines: analysis of mass extinction and ocean anoxia horizons, the geomicrobiology of cave sediments, the mineralogy of manganese ore deposits, tracing coal ash solids in river systems affected by coal ash spills, paleoenvironmental reconstruction of Miocene-age river systems and early human footprint sites in east Africa, and analysis of coprolites and volcanic ash deposits from Mesozoic sites in the southwestern United States. The new instrument will enhance observations and overall productivity these research projects as follows: it is a benchtop powder XRD system with a rotating sample changer, an internal chiller that does not require a special electrical outlet (allowing for flexibility if the instrument needs to be moved to another lab), a high-speed, high-resolution silicon strip detector for faster analysis speed (with a higher signal to noise ratio), and a removable graphite monochromater to help filter fluorescing phases (Fe, Ni, Co) and reduce noise to the data.

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.