New Results Concerning Expanded Networks of Obsidian Procurement in San Matías Gulf, Río Negro, Patagonia, Argentina

ABSTRACTIn this article we characterize the obsidian types present along the San Matias Gulf coast through geochemical analyses and we perform a techo-morphological analyses of the recovered artifacts. Also, we present a new obsidian type that has been found for the first time in the Atlantic coast of Patagonia. By this means we hope to better evaluate trends in the circulation and use of this raw material in the San Matias Gulf during the Middle and Late Holocene. As a result, we propose that there is a differential distribution between northern and southern Patagonia and among coastal sites (black and gray obsidians). This disparity could be mainly related to spatial distance, or to different mobility patterns of the human groups or to differential availability of the sources during the year. Growing evidence also suggests different raw material circulation.