MIDDLE TO LATE HOLOCENE RELATIVE SEA LEVEL CHANGES AT PUERTO DESEADO (PATAGONIA, ARGENTINA)

ZANCHETTA G.; BINI, M.; ISOLA, I.; PAPPALARDO, M.; RIBOLINI, A.; CONSOLONI I.; BORETTO G.M.; FUCKS, E.; RAGAINI L. ; TERRASI F.

HOLOCENE (SEVENOAKS)

SAGE PUBLICATIONS LTD

Lugar: London; Año: 2014 vol. 24 p. 307 - 317

0959-6836

Stratigraphic, morphologic and radiocarbon data from Puerto Deseado coastal area (Santa Cruz Province, Argentina) indicate that Holocene coast formed in response to the discontinuous aggradation of coarse gravely beach since ca. 6300 cal BP related to a progressive falling of relative sea level. Beach ridge crests crudely approximate the sea level showing at least 3 steps of aggradation and relative sea level lowering. Two inactive abrasive notches at ca. 6 and 1.8 m a.h.T. (above high tide) have recorded this sea level trend suggesting two important phases of sea level stationing. This allows to estimate a rate of relative sea level falling in the last ca. 3500 cal BP of ca 1.8 mm/a. Moreover, notches and morphological data indicate that the crest of the beach ridges overestimated the sea level of ca. 2±0.5 m. This values seems a reasonable regional correction to be applied to this sea level markers for producing comparable relative sea level curve for Atlantic Patagonia coast.