Radiocarbon reservoir ages and hardwater effect for the northeastern coastal waters of Argentina

Accelerator mass spectrometry (AMS) radiocarbon dates were obtained for 18 mollusk shells collected alive along the Buenos Aires province coast, Argentina, over the period AD 1914-1935. Reservoir ages were estimated for all samples on the basis of the tree-ring calibration curve for the Southern Hem...

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Detalles Bibliográficos
Autores: Gómez, Eduardo A., Borel, C. Marcela, Aguirre, Marina Laura, Martínez, Daniel E.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2008
País:Argentina
Institución:Universidad Nacional de La Plata
Repositorio:SEDICI (UNLP)
Idioma:inglés
OAI Identifier:oai:sedici.unlp.edu.ar:10915/83377
Acceso en línea:http://sedici.unlp.edu.ar/handle/10915/83377
Access Level:acceso abierto
Palabra clave:Ciencias Naturales
Datación por radiocarbono
coastal waters
Argentina
Descripción
Sumario:Accelerator mass spectrometry (AMS) radiocarbon dates were obtained for 18 mollusk shells collected alive along the Buenos Aires province coast, Argentina, over the period AD 1914-1935. Reservoir ages were estimated for all samples on the basis of the tree-ring calibration curve for the Southern Hemisphere (SHCal04, McCormac et al. 2004) and the marine ΔR values calculated as the difference between the conventional <SUP>14</SUP>C age and the age deduced from the marine, mixed-layer model calculation (Marine04, Hughen et al. 2004). For most coastal locations, a great ΔR scatter was observed, ranging from 191 to 2482 yr, which is explained by the input of varying content of dissolved carbonate by rivers and groundwater ("hardwater effect") and indicates a serious limitation for shell-based <SUP>14</SUP>C chronologies. Within the interior of Bahía Blanca estuary, ΔR values ranged from -40 to 50 ± 46 as a consequence of the local geological particularities of the environment. This suggests that, with some restrictions, the marine calibration curve with standard parameters (ΔR = 0) could be used at this location.