CONICET | Buscador de Institutos y Recursos Humanos

The study of the presence of obsidian in differentarchaeological sites in the northern coast of Patagonia (Argentina) has begunto be systematized in recent years. In particular, on the coast of San MatíasGulf (Río Negro province) it has been determined that this raw material ismostly represented along the west coast of the Gulf (Figure 1) and there hasbeen a general pattern of declining abundance from South to North. That is, onthe northern coast of the study area, the representation of this rock issignificantly lower (Cardillo and Scartascini 2007). Different sources oforigin of this rock have been detected through geochemical studies of recoveredsamples: Telsen and Sacanana in Chubut province (225 and 380 linear km distant,respectively), the Somuncurá plateau and Cantera Lolog (Neuquén province), thelatter located 560 linear km from the study area (Favier Dubois et al. 2009). Through the implementationof new geochemical analysis a sample from a new source has been detected on thewest coast of the Gulf. This sample comes from Portada Covunco in Neuquénprovince, 500 linear km away (Stern et al.2012). This finding is of particular importance since it is the first time thatthis type of obsidian, that has a visually distinctive red and black bandingand is also found on the Pacific Coast in Chile, is found on the Atlantic coastof Patagonia. In this paper obsidian we characterize the obsidiantypes present at San Matías gulf coast, we perform a techo-morphologicalanalyses of the recovered artifacts, and we make comparisons witharchaeological sites of the northern coast of Chubut (central Patagonia) todetect, in different parts of the coast, samples that come from the samesources. By this means we hope to better evaluate trends in the circulation anduse of this raw material at San Matías Gulf during the Middle and LateHolocene.