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

Online Access: Get full text
doi: 10.1016/j.quascirev.2013.08.014
Author(s): Naafs, B. David A.; Hefter, J.; Stein, R.
Author Affiliation(s): Primary:
Alfred Wegener Institute for Polar and Marine Research, Department of Marine Geology and Paleontology, Bremerhaven, Germany
Volume Title: Quaternary Science Reviews
Source: Quaternary Science Reviews, Vol.80, p.1-28. Publisher: Elsevier, International. ISSN: 0277-3791
Note: In English. 233 refs.; illus., incl. 2 tables, geol. sketch map
Summary: 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 (≈650 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. Abstract Copyright (2013) Elsevier, B.V.
Year of Publication: 2013
Research Program: IODP Integrated Ocean Drilling Program
Key Words: 12 Stratigraphy, Historical Geology and Paleoecology; Alkenones; Arctic region; Atlantic Ocean; Biomarkers; Cenozoic; Cores; Expedition 306; Expeditions 303/306; Fennoscandian ice sheet; Glacial geology; Greenland; Greenland ice sheet; Heinrich events; Hudson Strait; IODP Site U1313; Ice rafting; Ice sheets; Integrated Ocean Drilling Program; Ketones; Labrador Sea; Laurentide ice sheet; Marine sediments; Mid-Atlantic Ridge; Neogene; North Atlantic; Organic compounds; Paleoclimatology; Paleotemperature; Pleistocene; Pliocene; Quaternary; Sea-surface temperature; Sediments; Tertiary; Upper Pliocene
Coordinates: N410000 N410000 W0325700 W0325700
Record ID: 2014031581
Copyright Information: GeoRef, Copyright 2019 American Geosciences Institute. Reference includes data from CAPCAS, Elsevier Scientific Publishers, Amsterdam, Netherlands