Comparison of ESR and Amino Acid Data in Correlating and Dating Quaternary Shorelines Along the Patagonian Coast, Argentina
Keywords:Argentina, Patagonia, ESR, amino acid racemization, raised shorelines, Quaternary
Five areas along the Patagonian coast, Argentina, were sampled for ESR age estimates in order to elucidate earlier conclusions on the number, characteristics, geomorphology, correlation and amino acid age estimates of Quaternary shorelines in Patagonia (Rutter et al., 1989). Areas investigated include: San Blas, San Antonio Oeste, Caleta Valdes, Bahia Bustamante and Puerto Deseado. The ESR ages generally confirmed conclusions based on the amino acid data. The "oldest" shorelines are found at elevations between 24 and 41 m above mean sea level and are judged to represent the penultimate or older interglacial. The "intermediate" aged shorelines are present at some locations, represented by beach ridges varying between 20 and 28 m. These ridges were probably formed during the last interglacial (isotope stage 5e). Well defined "young" beach ridges between 8-12 m above mean sea level are found in most locations and have been 14C dated and verified by amino acid and ESR dates as Holocene in age.