Allen, Claire Susannah; Pike, Jennifer; Pudsey, Carol J; Leventer, Amy (2005): (Table 1) Age determination of sediment core KC073 [dataset]. PANGAEA, https://doi.org/10.1594/PANGAEA.837085, Supplement to: Allen, CS et al. (2005): Submillennial variations in ocean conditions during deglaciation based on diatom assemblages from the southwest Atlantic. Paleoceanography, 20(2), PA2012, https://doi.org/10.1029/2004PA001055
Always quote citation above when using data! You can download the citation in several formats below.
Abstract:
We present a high-resolution paleoceanographic record of deglaciation based on diatom assemblages from a core located just south of the Polar Front in the southwest Atlantic. Core KC073 is from a sediment drift at the mouth of the Falkland Trough and contains sediments from the Last Glacial Maximum (LGM) to present, dated using radiocarbon dates on bulk organic matter and radiolarian stratigraphy. The site lies along the path of the Antarctic Circumpolar Current (ACC) and immediately downstream of where North Atlantic Deep Water (NADW) is entrained into the ACC. Significant variations in ocean conditions are reflected in high-amplitude changes in diatom concentrations and assemblage composition. The diatom assemblage at the LGM indicates that winter sea ice extent was at least 5° farther north than present until at least 19.0 ka (calendar years) and summer sea ice may have occasionally extended over the site, but for the most part it lay to the south. During deglaciation, Chaetoceros resting spores (CRS) dominate the diatom assemblage with valve concentrations in excess of 500 * 10**6 valves per gram. Submillennial-scale variations in the numbers of CRS and Thalassiosira antarctica occur throughout the late deglacial and dominate the changes in diatom concentration. We propose that the influx of CRS is controlled by the flow of NADW over the Falkland Plateau. As such our data provide unique evidence that NADW impacted on this sector of the Southern Ocean during deglaciation. During the Holocene the sedimentation rate dramatically reduced. We suggest that the ACC flow increased over the site and inhibited settling and winnowed the surface sediments.
Coverage:
Latitude: -52.150000 * Longitude: -41.183330
Date/Time Start: 1995-01-01T00:00:00 * Date/Time End: 1995-01-01T00:00:00
Minimum DEPTH, sediment/rock: 0.005 m * Maximum DEPTH, sediment/rock: 2.605 m
Event(s):
Comment:
Age corrected using the regional 14C correction age of 1300 years B.P. and calibrated using CALIB 4.4.
Parameter(s):
| # | Name | Short Name | Unit | Principal Investigator | Method/Device | Comment |
|---|---|---|---|---|---|---|
| 1 | Laboratory code/label | Lab label | Allen, Claire Susannah | |||
| 2 | DEPTH, sediment/rock | Depth sed | m | Geocode | ||
| 3 | Depth, top/min | Depth top | m | Allen, Claire Susannah | ||
| 4 | Depth, bottom/max | Depth bot | m | Allen, Claire Susannah | ||
| 5 | Age, dated | Age dated | ka | Allen, Claire Susannah | Age, 14C AMS | |
| 6 | Age, dated standard deviation | Age dated std dev | ± | Allen, Claire Susannah | Age, 14C AMS | 1 sigma |
| 7 | Carbon | C | % | Allen, Claire Susannah | ||
| 8 | Calendar age, maximum/old | Cal age max | ka BP | Allen, Claire Susannah | Age, 14C calibrated, CALIB 4.4 (Stuiver et al., 2003) | |
| 9 | Calendar age, minimum/young | Cal age min | ka BP | Allen, Claire Susannah | Age, 14C calibrated, CALIB 4.4 (Stuiver et al., 2003) | |
| 10 | Calendar age | Cal age | ka BP | Allen, Claire Susannah | Age, 14C calibrated, CALIB 4.4 (Stuiver et al., 2003) | |
| 11 | Calendar age, standard deviation | Cal age std dev | ± | Allen, Claire Susannah | Age, 14C calibrated, CALIB 4.4 (Stuiver et al., 2003) | 1 sigma |
License:
Creative Commons Attribution 3.0 Unported (CC-BY-3.0)
Size:
60 data points