Geomorphological and techno-economic context of sites on the lower Uruguay River (left margin). Preliminary survey results

Abstract

This paper seeks to expand the knowledge of the use of space and the settlement, technology, and subsistence strategies used by the complex hunter-gatherer groups that inhabited the left bank of the lower Uruguay River basin during the Late Holocene (ca. 1900-500 BP). We present and discuss archaeological data recently obtained from surveys, test pits, and the analysis of local artifacts collections. The archaeological record of the area shows the exploitation of aquatic and terrestrial resources, the manufacture and use of pottery, and flaked and grounded lithic artifacts. The sites are mostly located in naturally elevated landforms such as sandy ridges and fluvial banks. The artifactual densities in the sites and their chronological variability, show that these populations developed a low mobility settlement pattern, similar to the “base camp” scheme. The results of the surveys and the detailed available analyses of the sedimentological composition of the sites indicate the absence of built structures. Despite this, there are technological, stylistic, and economic similarities that allow us to relate the occupations on the eastern margin of the lower Uruguay River with different archaeological units corresponding to complex hunter-gatherer groups identified on the right bank of the Uruguay River, and in the middle and lower Paraná. Finally, the presence of Guarani groups has also been identified in the area through the corrugated and painted ceramic styles. In most cases, the Guarani evidence is associated with hunter-gatherer contexts.