Palaeoenvironmental reconstruction of La Olla, a Holocene archaeological site in the Pampean coast (Argentina)
Autor
Blasi, Adriana
Politis, Gustavo
Bayón, María Cristina
Institución
Resumen
The evolution of littoral palaeoenvironments in the southern Pampas region of Argentina towards the
end of the early Holocene and the beginning of the mid Holocene is discussed, and the formation
processes of the archaeological site of La Olla are analysed. This site is located in the intertidal zone of the
present beach and is remarkably well-preserved. The human occupation at the site has been dated at
between 7400 and 6480 yrs BP, and is interpreted as a place for the processing and consumption of the
southern fur seal (Arctocephalus australis) and southern sea-lion (Otaria flavescens). It is concluded that
biostabilization by microbial mats of the sedimentary structures and archaeological remains that
developed and are present on the tidal flat prevented their erosion by wind, turbulence currents and
waves. This is what has permitted the exceptional preservation of the site. On the basis of the analyses of
one of the sectors of the site it can be concluded that the sedimentary succession of the La Olla site is the
result of the coastal environmental changes during the earlyemid Holocene in the pre-maximum
transgressive episode. During this interval a tidal flat developed on the Pleistocene abrasion platform.
Human occupation occurred during the formation of mixohaline marsh, an upper intertidalelower
supratidal zone ecosystem.