GEOCHEMICAL ANALYSIS OF OBSIDIAN FROM ARCHAEOLOGICAL SITES IN NORTHWESTERN SANTA CRUZ PROVINCE, ARGENTINE PATAGONIA

MARÍA VICTORIA FERNÁNDEZ; CHARLES R. STERN; LEAL PABLO R.

QUATERNARY INTERNATIONAL

PERGAMON-ELSEVIER SCIENCE LTD

Lugar: Amsterdam; Año: 2015 vol. 375 p. 44 - 54

1040-6182

In central and southern Patagonia obsidian raw material has been widely used from the beginning of the occupation of this region. In NW Santa Cruz province, Argentina, the geochemical analyses published to date suggest that Pampa del Asador obsidian was the main source. However, both the spatial and temporal limits and extent of the distribution and circulation of this obsidian remain undefined. The principal goal of this article is to characterize the obsidian from archaeological sites located in a portion of NW Santa Cruz, from which there is no available geochemical information. ICP-MS analyses were obtained for 49 obsidian artifacts recovered from 23 excavated rockshelters and open-air surface scatters. The results indicate that almost all the samples came from the Pampa del Asador source, located ca. 90 km to the south. Two samples of grey obsidian discovered on the top of Meseta del Lago Buenos Aires are chemically different from any other archeological obsidian yet analyzed in southern Patagonia. Their source is still unknown, but they are most likely derived from a local Meseta del Lago Buenos Aires obsidian source. With these results we contribute to the knowledge about the use of obsidian, which is a useful indicator of the communication between different environments and basins on a regional scale.