This document discusses the provenance of quartz arenite sandstones from the early Paleozoic midcontinent region of the USA. The authors present new detrital zircon geochronology data from 15 Cambrian and Ordovician quartz arenite samples. They compare this to existing data from older sedimentary basins in the region, including the Huron basin and midcontinent rift deposits. Mixing models using the older basin zircon populations indicate the early Paleozoic sandstones represent mixtures derived primarily from erosion of these two source areas.