CADIC   02618
CENTRO AUSTRAL DE INVESTIGACIONES CIENTIFICAS
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Paleogeographic evolution of Patagonia and its continental shelf from the Last Glacial Maximum to the early Holocene
Autor/es:
PONCE, J. F.; RABASSA, J. O.; CORONATO, A.
Lugar:
Bariloche
Reunión:
Congreso; VI Sothern Connection Congress; 2010
Institución organizadora:
Universidad Nacional del Comahue, Conicet, INTA
Resumen:
We developed a model of sea level change to describe the paleogeographic evolution of Patagonia and its continental shelf from the Last Glacial Maximum (LGM, ca. 24 cal. ka BP) to the early Holocene. Sea level during the LGM was 120-140 m below present level leaving a vast area (ca. 0.6 million km2) of the current continental shelf exposed. The emerged area during the LGM varied in width from ca. 500 km to 100 km at the latitudes of Bahía Blanca and Tierra del Fuego, respectively. The Malvinas archipelago comprised a single large island (46,000 km2), four times larger than the currently exposed area. It was separated from the continent by a straight 220 km long. Another island (ca. 13,600 km2) likely existed in the area currently known as Burkwood Bank, south of Malvinas from the beginning of MIS 2 (ca. 30-40 ka BP) to ca. 15.5 cal. ka BP. The exposed area of the current continental shelf is likely to have been halved around 15.3 cal. ka BP when sea level was ca. 90 m below present level. The current coastline was likely in place between 11 and 9 cal. ka BP. The straight of Magellan is likely to have been formed ca. 10.2 cal. ka BP when sea level rose to ca -35 m. Our model facilitates paleoenvironmental and paleoclimatic reconstructions that may help understand faunal/floral dispersal throughout the region during the Late Glacial period and early Holocene. Our method could also be useful for the reconstruction of the paleogeography of earlier glacial-interglacial transitions