Age determination and sedimentation rates of the subpolar northeast Atlantic

DOI

In order to monitor the evolution of the British-Irish Ice Sheet (BIIS) and its influence in surface ocean structure during marine isotopic stages (MIS) 2 and 3, we have analyzed the sediments recovered in core MD04-2829CQ (Rosemary Bank, north Rockall Trough, northeast Atlantic) dated between ~41 and ~18 ka B.P. Ice-rafted debris flux and composition, 40Ar/39Ar ages of individual hornblende grains, multispecies planktonic stable isotope records, planktonic foraminifera assemblage data and faunal-based sea surface temperatures (SSTs) demonstrate a close interaction between BIIS dynamics and surface ocean structure and water properties in this region. The core location lies beneath the North Atlantic Current (NAC) and is ideal for monitoring the shifts in the position of its associated oceanic fronts, as recorded by faunal changes. These data reveal a succession of BIIS-sourced iceberg calving events related to low SST, usually synchronous with dramatic changes in the composition of the planktonic foraminifera assemblage and with variations in the stable isotope records of the taxa Neogloboquadrina pachyderma (sinistral coiling) and Globigerina bulloides. The pacing of the calving events, from typically Dansgaard-Oeschger millennial timescales during late MIS 3 to multicentennial cyclicity from ~28 ka B.P., represents the build-up of the BIIS and its growing instability toward Heinrich Event (HE) 2 and the Last Glacial Maximum. Our data confirm the strong coupling between BIIS instabilities and the temperature and salinity of surface waters in the adjacent northeast Atlantic and demonstrate the BIIS's ability to modify the NAC on its flow toward the Nordic Seas. In contrast, subsurface water masses were less affected except during the Greenland stadials that contain HEs, when most intense water column reorganizations occurred simultaneously with the deposition of cream-colored carbonate sourced from the Laurentide Ice Sheet.

Supplement to: Hall, Ian R; Colmenero-Hidalgo, Elena; Zahn, Rainer; Peck, Victoria L; Hemming, Sidney R (2011): Centennial- to millennial-scale ice-ocean interactions in the subpolar northeast Atlantic 18-41 kyr ago. Paleoceanography, 26(2), PA2224

Identifier
DOI https://doi.org/10.1594/PANGAEA.830624
Related Identifier https://doi.org/10.1029/2010PA002084
Metadata Access https://ws.pangaea.de/oai/provider?verb=GetRecord&metadataPrefix=datacite4&identifier=oai:pangaea.de:doi:10.1594/PANGAEA.830624
Provenance
Creator Hall, Ian R ORCID logo; Colmenero-Hidalgo, Elena ORCID logo; Zahn, Rainer; Peck, Victoria L; Hemming, Sidney R ORCID logo
Publisher PANGAEA
Publication Year 2011
Rights Creative Commons Attribution 3.0 Unported; https://creativecommons.org/licenses/by/3.0/
OpenAccess true
Representation
Language English
Resource Type Supplementary Publication Series of Datasets; Collection
Format application/zip
Size 2 datasets
Discipline Earth System Research
Spatial Coverage (-9.572 LON, 58.949 LAT); Northeast Atlantic