Obsidian circulation in Chubut, central Patagonia, Argentina: use of extra regional raw materials as a sign of mobility and interaction between hunter gatherers groups

Abstract

The lithic assemblages recovered from various types of archaeological sites in Chubut, central Patagonia, show a predominance of local raw materials such as silica, xilopals and vulcanite. These materials are available in the vicinities of these sites. Obsidians, however, scarcely appear in archaeological sets and are not found in local quarries. The availability of geochemically characterized obsidian sources, precisely located in the Patagonian area, allowed the identification of the source location of those found in archaeological contexts. This paper presents the results of the geochemical analysis of obsidian artifacts from several sites inside Chubut and they are discussed in relation to the mobility circuits of human groups along structured routes. The conclusions suggest not only the existence of communication corridors but also of crossroads. Finally, the use of obsidians associated with social or symbolic aspects, opposed to a merely technological application, is argued.