Pre-Hispanic earthwork engineering variability in the Upper Delta of the Paraná River. A comparative study between Los Tres Cerros mounds (Entre Ríos province, Argentina)

Abstract

Earthworks are one of the most distinctive archaeological features in the wetland landscapes of South America. Herein, we provide a case study from one of the southernmost expressions of this earthworking phenomenon, the Paraná River Delta. In this flood-prone wetland, occupation strategies included the construction and habitation of earth-mounds and other topographically elevated areas in order to cope with deluges in a hydrometeorologically susceptible environment. We carried out planialtimetrical, sedimentary, bio-compositional and chronological analyses of the sedimentary matrix of two anthropogenical earthmounds, Los Tres Cerros site 1 and 2, and the results were compared in order to detect similarities and differences in the overall moundbuilding process. Besides its temporal and spatial closeness the succession of alternating humic and charcoal enriched lenses conforms surfaces were conditioning and maintenance activities were developed in both mounds, but the selection and sourcing of materials used in its construction presents notorious differences. Finally, we addresses the occupational strategies that guided the pre-Hispanic human settlement in lowland areas of southern South America and contribute to the acknowledgment of earthwork engineering variability in order to understand the evolution processes of the archaeological landscape of Los Tres Cerros archaeological locality.