Short Paper: Arc detritus in the Southern Uplands: mineralogical characterization of a ‘missing’ terrane

Abstract
Within the late Ordovician-early Silurian Southern Uplands thrust belt, quartzo-feldspathic greywackes derived from the north are interbedded with volcanic-rich greywackes of southerly provenance. Abundant fresh clinopyroxenes which occur in the latter, both as single crystals and phenocrysts in lithic fragments, have compositions that indicate a calc-alkaline island arc origin.