Nd isotope data for ODP Leg 208 holes

DOI

The flow of deep-water masses is a key component of heat transport in the modern climate system, yet the role of deep-ocean heat transport during periods of extreme warmth is poorly understood. The present mode of meridional overturning circulation is characterized by deep-water formation in both the North Atlantic and the Southern Ocean. However, a different mode of meridional overturning circulation operated during the extreme greenhouse warmth of the early Cenozoic, during which time the Southern Ocean was the dominant region of deep-water formation. The combination of general global cooling and tectonic evolution of the Atlantic basins over the past ~55 m.y. ultimately led to the development of a mode of overturning circulation characterized by both Southern Ocean and North Atlantic deep-water sources. The change in deep-water circulation mode may, in turn, have affected global climate; however, unraveling the causes and consequences of this transition requires a better understanding of the timing of the transition. New Nd isotope data from the southeastern Atlantic Ocean indicate that the initial transition to a bipolar mode of deep-water circulation occurred in the early Oligocene, ca. 33 Ma. The likely cause of significant deep-water production in the North Atlantic was tectonic deepening of the sill separating the Greenland-Norwegian Sea from the North Atlantic.

Supplement to: Via, Rachael K; Thomas, Deborah J (2006): Evolution of Atlantic thermohaline circulation: Early Oligocene onset of deep-water production in the North Atlantic. Geology 2006, 34(6), 441-444

Identifier
DOI https://doi.org/10.1594/PANGAEA.724682
Related Identifier https://doi.org/10.1130/G22545.1
Related Identifier ftp://rock.geosociety.org/pub/reposit/2006/2006087.pdf
Metadata Access https://ws.pangaea.de/oai/provider?verb=GetRecord&metadataPrefix=datacite4&identifier=oai:pangaea.de:doi:10.1594/PANGAEA.724682
Provenance
Creator Via, Rachael K; Thomas, Deborah J
Publisher PANGAEA
Publication Year 2006
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 3 datasets
Discipline Earth System Research
Spatial Coverage (1.577W, -28.533S, 2.846E, -27.186N); Walvis Ridge, Southeast Atlantic Ocean
Temporal Coverage Begin 2003-03-24T13:00:00Z
Temporal Coverage End 2003-04-06T21:55:00Z