Deep sea sedimentary analogs for the Vostok ice core

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doi: 10.1029/2002GC000475
Author(s): Mortyn, P. Graham; Charles, Christopher D.; Ninnemann, Ulysses S.; Ludwig, Kristen; Hodell, David A.
Author Affiliation(s): Primary:
Scripps Institution of Oceanography, La Jolla, CA, United States
Other:
University of Florida, United States
Volume Title: Geochemistry, Geophysics, Geosystems - G<sup>3</sup>
Source: Geochemistry, Geophysics, Geosystems - G>3`, 4(8). Publisher: American Geophysical Union and The Geochemical Society, United States. ISSN: 1525-2027
Note: In English. 46 refs.; illus., incl. table, sketch map
Summary: Many applications of the Vostok ice core depend critically on the ability to make stratigraphic ties to marine records in the adjacent Southern Ocean. Here we present oxygen isotopic records from high accumulation rate sites in the South Atlantic sector of the Southern Ocean, collected for the purpose of complementing the recently extended δD record from the Vostok ice core. The combination of several planktonic foraminiferal δ18O records from northern subantarctic piston cores demonstrates that all of the millennial-scale oscillations expressed in the Vostok ice core over the last 60 ky are also present in marine records. The observations also support the assumption that the millennial-scale oscillations common to both marine and ice archives are synchronous, thus providing a rationale for extending the marine-ice core comparison through the last 400,000 years, making use of a marine drilled core (ODP Site 1089). By aligning the phase of these common abrupt events, we anchor the Vostok chronology to an orbitally tuned marine sediment chronology--a refinement that allows examination of a variety of paleoclimatological issues such as the relationship between deep ocean variability and Antarctic polar climate. For example, this exercise suggests that, over at least the 4 major deglaciation events, the primary (orbital scale) changes in the chemistry and, most likely, the temperature of the deep Southern Ocean were synchronous with changes in atmospheric pCO2 and polar air temperatures. We also find that the deuterium excess in the ice core resembles marine (foraminiferal) 13C records and that the deuterium excess is synchronous with an "anomalous" foraminiferal 18O signal (the residual between normalized versions of Vostok D and foraminiferal 18O). These observations demand a tight link between the Vostok isotopic record and the air-sea interaction of the subantarctic zone.
Year of Publication: 2003
Research Program: ODP Ocean Drilling Program
Key Words: 06 Petrology, Sedimentary; 24 Surficial Geology, Quaternary Geology; Antarctica; Benthic taxa; Cenozoic; Deep-sea sedimentation; Deuterium; Foraminifera; Globigerina; Globigerina bulloides; Globigerinacea; Globigerinidae; Holocene; Hydrogen; Ice cores; Invertebrata; Isotope ratios; Isotopes; Leg 177; Marine sedimentation; Marine sediments; Microfossils; O-18/O-16; ODP Site 1089; Ocean Drilling Program; Oscillations; Oxygen; Paleo-oceanography; Paleoclimatology; Paleoenvironment; Periodicity; Protista; Quaternary; Rotaliina; Sedimentation; Sediments; Southern Ocean; Stable isotopes; Upper Holocene; Vostok Station
Record ID: 2005064341
Copyright Information: GeoRef, Copyright 2018 American Geosciences Institute. Reference includes data supplied by, and/or abstract, Copyright, American Geophysical Union, Washington, DC, United States

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