Millennial-scale ice rafting events and Hudson Strait Heinrich(-like) Events during the late Pliocene and Pleistocene: a review

B D A Naafs, Jens Hefter, Ruediger Stein

Research output: Contribution to journalArticle (Academic Journal)

59 Citations (Scopus)

Abstract

Various types of abrupt/millennial-scale climate variability such as Dansgaard/Oeschger and Heinrich Events characterized the last glacial period. Over the last decade, a number of studies demonstrated that such millennial-scale climate variability was not limited to the last glacial but inherent to Quaternary climate. Here we review the occurrence and origin of millennial ice-rafting events in the North Atlantic during the late Pliocene and Pleistocene (last 3.4 Ma) with a special focus on North Atlantic Hudson Strait (HS) Heinrich(-like) Events. We show that Heinrich Layers 5, 4, 2, and 1 in marine sediment cores from across the North Atlantic all bear the organic geochemical fingerprint of the Hudson area. Using this framework and combining previously published results, detailed investigations into the organic and inorganic chemistry of ice rafted debris (IRD) found across the North Atlantic demonstrate that prior to MIS 16 (w650 ka) IRD in the North Atlantic did not originate from the Hudson area of northern Canada. The signature of this early IRD is distinctly different compared to that of HS Heinrich Layers. Rather ice-rafting events during the
late Pliocene and early Pleistocene predominantly emanated from the calving of the Greenland and Fennoscandian ice sheets and possibly minor contributions from local ice streams from the North American and British ice sheets. Compared to North Atlantic HS Heinrich Events, these early Pleistocene IRD-events had a limited impact on surface water characteristics in the North Atlantic. North Atlantic HS Heinrich(-like) Events first occurred during MIS 16. At the same time, the dominant frequency in silicate rich IRD accumulation shifted from the obliquity (41-ka) to a 100-ka frequency across the North Atlantic. Iceberg survivability or a change in iceberg trajectory likely did not control this change in IRD-regime. These results lend further support for the existing hypothesis that an increase in size (thickness) of the Laurentide ice sheet controls the occurrence of North Atlantic HS Heinrich Events, favoring an internal
dynamic mechanism for their occurrence.
Original languageEnglish
Pages (from-to)1-28
Number of pages28
JournalQuaternary Science Reviews
Volume80
DOIs
Publication statusPublished - 2013

Fingerprint Dive into the research topics of 'Millennial-scale ice rafting events and Hudson Strait Heinrich(-like) Events during the late Pliocene and Pleistocene: a review'. Together they form a unique fingerprint.

  • Cite this