Sedimentology, planktonic foraminifera distribution and stable isotope composition during marine isotope stage 3 of ODP Site 172-1060 in the West Atlantic, supplement to: Vautravers, Maryline J; Shackleton, Nicholas J; López-Martinez, Constancia; Grimalt, Joan O (2004): Gulf Stream variability during marine isotope stage 3. Paleoceanography, 19(2), PA2011

We have studied Ocean Drilling Program Site 1060 on the Blake Outer Ridge, which lies beneath the Gulf Stream. We focus on marine isotope stage 3, 60-25 thousand years before present (ka). Sea surface temperatures (SSTs) inferred both from foraminiferal fauna and alkenone ratios, as well as counts o...

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Bibliographic Details
Main Authors: Vautravers, Maryline J, Shackleton, Nicholas J, López-Martinez, Constancia, Grimalt, Joan O
Format: Article in Journal/Newspaper
Language:English
Published: PANGAEA - Data Publisher for Earth & Environmental Science 2004
Subjects:
Composite Core
Leg172
Joides Resolution
Ocean Drilling Program ODP
Greenland
Shackleton
Greenland ice cores
ice core
North Atlantic
Planktonic foraminifera
Online Access:https://dx.doi.org/10.1594/pangaea.707201
https://doi.pangaea.de/10.1594/PANGAEA.707201
Description
Summary:We have studied Ocean Drilling Program Site 1060 on the Blake Outer Ridge, which lies beneath the Gulf Stream. We focus on marine isotope stage 3, 60-25 thousand years before present (ka). Sea surface temperatures (SSTs) inferred both from foraminiferal fauna and alkenone ratios, as well as counts of iceberg melt-out debris and benthic stable isotope analyses, enable our record to be interpreted in terms of regional hydrographic changes as well as changing thermohaline circulation (THC). The observed SST record is consistent with the air temperature record from the Greenland ice cores. However, Site 1060 exhibits important differences in detail compared with the ice core record, and when compared to other sites within the North Atlantic, significant longitudinal differences emerge. At Site 1060 in the western Atlantic, all Greenland stadials (GS) whether associated with Heinrich events (HEs) or not, show a similar small amplitude of cooling; mean faunal-based SSTaug during GS is only 1.5°C colder than during Greenland interstadials (GIS). In addition, during GS the coldest SSTs are limited to apparently brief events. This is in contrast to several eastern Atlantic sites where HE stadials exhibit coolings that are enhanced by 2°C compared to other GS and where cold conditions are not restricted to cold pulses but cover 2 ka-long intervals. Furthermore, Site 1060 SSTs remained warm right through each interstadial, in contrast to the sustained and uniform cooling trend through interstadials that is consistently observed in Greenland, indicated by measurements of delta18O in ice.

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