Holocene beach ridge evolution at Río de la Plata estuary, Argentina: Former answers for future questions?

Abstract

The Holocene shows rapid climatic changes associated with alternating intervals of glacier advances and retreats. The coastal regions, where beach ridges constitute common preserved landforms, are highly sensitive to register such changes and bring light into past littoral environments. Excellent marine Argentinean Holocene deposits associated with the last climate optimum are preserved at the Río de la Plata estuary (Argentina). In this beach ridge a palaeoenvironmental model was performed, including the analysis of major hierarchy surfaces (clinoforms) that subdivide it into eleven clinothems (two siliciclastic; nine carbonatic). Selected clinothems were dated between 5,240±110 and 3,900±90 calBP, while stable isotope analyses allowed to infer that the temperature during the evolution of the ridge has two maximum values of 22.5 ºC.