Cathodoluminescence spectra of detrital quartz as provenance indicators for Paleozoic metasediments in southern Andean Patagonia

The cathodoluminescence (CL) characteristics of single quartz grains are indicative of provenance. In this study, we compare the CL spectra of individual quartz grains to reveal the ‘true’ CL color more precisely than the subjective optical identification of CL colors can. Our data are from Late Devonian-Early Carboniferous metaturbidites in southern Chile and Argentina (47°–49°S, 72°–73°W) that belong to the basement of the Andes. The quartz CL spectra reveal dominant quartz grains of regional metamorphic and plutonic origin in the studied sediments. This study supports the theory that the depositional basin was situated in a passive margin environment. Therefore, Late Paleozoic easterly directed subduction beneath present southern Patagonia had not commenced in Late Devonian-Early Carboniferous times.