Late Holocene climatic fluctuations and soil genesis in southern Patagonia: effects on the archaeological record

Geoarchaeological research conducted at five localities in southern Patagonia and Tierra del Fuego identified a mollisol within late Holocene aeolian and colluvial deposits associated with archaeological material. The mollisol's origin and development are related to an increase in humidity (c. 1000 BP) following an episode of severe drought during the Medieval Warm Period. Corroborating data is supplied from dendroclimatic and pollen studies. A drastic reduction in frequency of artefact distribution recorded at the sites studied corresponds to this pedologic event, suggesting a greater human presence at these sites during earlier, regional-scale arid conditions. However, the paucity of archaeological remains may also be the result of the low resolution of cultural evidence following the pedologic development due to superimposition over previous archaeological deposits.