Heinrich Events are intermittent periods of iceberg surges and meltweater flow mainly from the Laurentide ice sheet that occurred during glacial times. Iceberg drift and meltwater influx was largest in a belt between 40° and 50°N (Bond et al., 1992; Bond and Lotti, 1995). Enhanced meltwater flux caused a significant decrease in sea surface temperatures and salinities, and it destabilized or even stopped thermohaline circulation in the glacial North Atlantic (Zahn et al., 1997). Heinrich Events are characterized by massive, short-term occurrences of the polar planktonic foraminifer Neogloboquadrina pachyderma (sinistral) and coarse lithic grains of North American origin (Baas et al., 1997, de Abreu et al., 2003). These levels are denominated as Heinrich layers may be used to establish a chronostratigraphic framework for sediment cores (Lebreiro et al., 1996; Schönfeld and Zahn, 2000).
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