Magnetostratigraphy of the Patagonian moraine sequence at Lago Buenos Aires

Abstract

In the Lago Buenos Aires area, fifteen separate terminal moraines were identified that are grouped into five major zones representing “ice ages” or glaciation complexes. Paleomagnetism of proglacial sediments from beneath the terminal moraines indicates that the innermost eight moraines (and two zones) have a normal (Brunhes) polarity and the outermost five moraines (and two zones) have a reversed (Matuyama) polarity. This suggests that the original chronology of Caldenius from 1932 — and hence correlations with the Northern Hemisphere — must be completely revised.