X-ray Fluorescence Analysis of Basaltic Flows at Amboy Crater: Can a Calibrated, Handheld Niton XRF Analyzer Define Relative Age Relations between Flows?

Event Center A & B

This project sought to determine some of the capabilities of the handheld Niton x-ray fluorescence analyzers (Niton) when used for geologic fieldwork. In particular, analysis of lava flows at Amboy Crater, California was undertaken with the goal of determining relative ages by measuring nickel concentration in the lavas and pyroclastic deposits and comparing results to predicted fractional crystallization trends. Levels of nickel when plotted against zircon seemed to show a complex series of cone and flow events; however variability in composition was significant enough to make initial comparisons somewhat subjective. The Niton’s accuracy and precision in measuring various other elements was undertaken in order to determine whether measurements of those elements could be reliably used in estimating the relative age of the flows. Results varied by element and by the setting under which measurements were obtained, but some of the other elements besides nickel did show promise. Results indicate further field work is required to accurately characterize the utility of the Niton for this kind of geological work.