Petrographic thin sections and exotic rocks provenience among hunter–gatherer societies in the eastern Pampa–Patagonia Transition (lower basin of the Colorado River,Argentina)*

Lithic assemblages recovered from sites located in the eastern Pampa–Patagonia transition include a great diversity of raw materials, some from neighbouring regions, such as the Humid and Dry Pampa subregions and Northpatagonia. Lithic raw material assignments to specific procurement areas were preliminarily proposed based on macroscopic characterizations. The aim of the paper is to present the results obtained from the petrographic thin sections of archaeological artefacts from Middle and Late Holocene sites recorded at the study area. The analyses corroborate most of the macroscopic determinations, and more detailed knowledge of the acquisition areas of these raw materials was obtained.