Deconstructing a complex obsidian landscape in northwestern Patagonia: a geoarchaeological and geochemical approach

MACDONALD, B.; FERNANDEZ, V.; BARBERENA, R; RUGHINI, A.; CORTEGOSO, V. ; -DURÁN, V. Y V. CORTEGOSO; GLASCOCK, M.

Buenos Aires

Congreso; 11th Symposium on Knappable Materials; 2017

Instituto Multidisciplinario de Historia y Ciencias Humanas-CONICET

The spatial structure of obsidian sources in Northwestern Patagonia is highly complex, presenting both a challenge and an opportunity to reconstruct human patterns of mobility and technological organization. Until recently, available information suggested that the Cerro Huenul type was located in the lowlands (900-1100 masl), while the Laguna del Maule, with two chemical types, was situated in the Andean highlands (above 2000 masl). Accordingly, these chemical types have been used as proxies for human movements between different altitude settings. However, recent geoarchaeological and geochemical information suggests that volcanic and geomorphic processes have transported obsidian nodules across the region, preventing any straightforward spatial analysis. In this presentation we show new field and lab results for northern Neuquén Province (Argentina). These results suggest that the different obsidian types have a highly complex spatial structure encompassing the highlands to the lowlands, and overlapping in specific areas. While this new geological framework for obsidian sources prevents doing direct macro-regional reconstructions of mobility across altitudinal levels, the complexity of data available opens the way for more fine-grained assessments of human movements at micro-regional scales. In the future, spatial trajectories of reduction will play a key role in this endeavor.