ASSESSING HYDROTHERMAL ALTERATION INTENSITY IN VOLCANIC-HOSTED MASSIVE SULFIDE SYSTEMS USING PORTABLE X-RAY FLUORESCENCE ANALYSIS OF DRILL CORE: AN EXAMPLE FROM MYRA FALLS, CANADA

摘要

Current portable X-ray fluorescence (pXRF) technology can rapidly and inexpensively yield concentrations of geologically significant elements, typically with instrument detection limits below several tens of parts per million. Based on conventional XRF whole-rock geochemical data, both the Ishikawa alteration index and the chlorite-carbonate-pyrite index increase with proximity to sulfide mineralization at Myra Falls. However, available pXRF technology is typically unable to detect all the elements required to calculate these alteration indices. As a result, there is a need to utilize the elements that are readily detectable using pXRF and apply these to hydrothermal alteration assessment.