(super 14) C age of glaciation in Estrecho de Magallanes-Bahia Inutil, Chile.

Abstract

Basal (super 14) C dates from a core of the mire at Puerto del Hambre (53 degrees 36'21"s, 70 degrees 55'53"W), located within the area of glaciation in Estrecho de Magallanes-Bahia Inutil, Chile, are no older than 14,455+ or -115 yr BP. The (super 14) C dates are on samples from which screening isolated autochthonous plant remains. Previous (super 14) C dates of 15,800+ or -200, 16,590+ or -320, and 16,290+ or -140 yr BP are from bulk samples collected from similar basal increments at the site during 3 separate, independent coring operations. The previous suite of (super 14) C dates was suspected to be contaminated by older carbon in the light of chronological evidence, which indicates a (super 14) C age of approximately 14,850 yr BP for glaciation elsewhere in southern Chile. Contamination by "infinitely old" carbon reworked from nearby Tertiary beds and redeposited at Puerto del Hambre is evidently the cause for the older (super 14) C dates.