Geoarchaeology and taphonomy: Deciphering site formation processes for late Holocene archaeological settings in the eastern Pampa-Patagonian transition, Argentina

Assessing the integrity and resolution of archaeological sites in sandy environments is a key issue for understanding site formation processes in hunter-gatherer's contexts. A case study from the lower course of the Colorado River, at the eastern Pampa-Patagonian transition (Argentina) is presented here. The studied area is characterized by a sand dune relief that is superimposed upon ancient fluvial and marine environments. The sites date to between c. 2000 and 250 C-14 yr BP (late Holocene) and they are mostly located in eolian contexts. The objective of this paper is to understand environmental dynamics and the site formation processes that operated in archaeological sites of the late Holocene through the integration of geoarchaeological and taphonomic information. The obtained results allowed the identification of site formation processes related to the different environmental settings (coast, ancient delta and inland). However, general patterns that relate some taphonomic effects as root action and weathering with landscape processes such as pedogenesis at an areal scale were also recognized. Despite the varied and highly dynamic environmental conditions of this arid-semiarid area, archaeological contexts with good degrees of resolution and integrity were recognized.