The Late Quaternary Landscape History of the Middle Rio Negro Valley, Northern Patagonia, Argentina: Its Impact on Preservation of the Archaeological Record and Influence on Late Holocene Human Settlement Patterns

Geoarchaeological investigations were conducted in the Middle Río Negro\nValley in the northern portion of Patagonia, Argentina from 2004-2005. This project\nworked in conjunction with archaeological investigations in this region conducted by\nLic. Luciano Prates (Universidad Nacional de La Plata, Argentina). No previous studies\non the detailed reconstruction of the landscape history had been conducted in this valley.\nIn order to place the archaeological record in this landscape context, this project had four\nmain research objectives: 1) to reconstruct the landscape history; 2) to incorporate the\nknown archaeological record into this landscape history; 3) to interpret natural formation\nprocesses and evaluate the preservation potential for archaeological sites; and 4) to\ninterpret how landscape history could have influenced settlement patterns. Altogether,\nsix months of fieldwork consisted of field reconnaissance of the landscape and recording\nof the regional stratigraphy through detailed analysis of sediments and soils,\ngeomorphological features, and archaeological sites. This fieldwork was combined with\nanalysis of aerial photographs, topographical and geological maps, and sedimentological samples, in addition to the incorporation of radiocarbon and optically stimulated\nluminescence dating of stratigraphic units. As a result, through landscape\nreconstruction, it was possible to evaluate the preservation of the archaeological record,\nits landscape context, and to construct a predictive model for the location of\narchaeological sites from the Late Pleistocene through Late Holocene. Study of Late\nHolocene channel avulsion and the formation of pools within abandoned avulsion\nchannels which occurred in one part of the study area suggest that landscape change\npotentially influenced Late Holocene settlement patterns in the Middle Río Negro\nValley.