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Summary
This dataset includes d18O values measured from Globigerina bulloides,
Neogloboquadrina pachyderma (s.) and Globorotalia inflata from moored sediment
traps at:
NCR: 42 42S; 178 38E
SCR: 44 37S; 178 37E
SAZ: 46 45.6S; 142 4.2E
SAF: 51 0.01S; 141 44.3E
PFZ: 53 44.8S; 141 45.5E

Ten specimens in the 250-355 µm size fraction were ... analysed per sample for G.
bulloides and G. inflata, and 15-20 specimens in the 150-250 µm size fraction
were analysed for N. pachyderma (s.). The Chatham Rise (NCR and SCR) samples
were analysed at the Central Sciences Laboratory, University of Tasmania on an
individual reaction-vial automated carbonate line coupled to a Micromass
Optima mass spectrometer. Analytical precision was ±0.08 for d13C and ±0.09
for d18O (N = 51). The other samples (SAZ, SAF and PFZ) were analysed on a
Micromass Optima at UC Davis. The average analytical precision for these
measurements was ±0.05 for d13C, and ±0.06 for d18O (N = 28). The isotopic
ratios are reported as per mil (0) deviations from the Pee Dee belemnite (PDB)
standard using Carrara marble as a laboratory standard.

The King and Howard (2004) d13C data is available at:
ftp://ftp.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/king...


Abstract:
The oxygen isotopic record obtained from Globigerina bulloides, Globorotalia
inflata and Neogloboquadrina pachyderma (s.) was analysed for 5 sediment traps
moored in the Southern Ocean and Southwest Pacific. The traps extend from
Subtropical to the Polar Frontal environments, providing the first analysis of
seasonal foraminiferal d18O records from these latitudes. Comparison between
the foraminiferal records and various equations for predicted d18O of calcite
reveals that the predicted d18O is best captured by the equations of Epstein
et al. (1953) and Kim and O'Neil (1997). The Epstein equation shows a constant
offset from the d18O of G. bulloides and N. pachyderma (s.) across the full
range of latitudes. The seasonal range in d18O values for these two species
implies a near-surface habitat across all sites, while G. inflata most likely
dwells at ~50m depth. A significant finding in this study was that offsets
from predicted d18O for G. bulloides do not correlate to changes in the
carbonate ion concentration. This suggests that [CO32-] in and of itself may
not capture the full range of carbonate chemistry conditions in the marine
system. This sediment trap deployment also reveals distinct seasonal flux
patterns for each species. Comparison between flux-weighted isotopic values
calculated from the sediment traps and the isotopic composition of nearby
surface sediments indicates that the sedimentary records retain this seasonal
imprint. At the 51°S site, G. bulloides has a spring flux peak while N.
pachyderma (s.) is dominated by summer production. The imprint of these
differing seasonal production patterns on the flux-weighted d18O values
results in more depleted d18O for N. pachyderma (s.) than for G. bulloides.
Interpretations of N. pachyderma (s.) isotopic composition as a record of
subsurface conditions may therefore need to be refined, with implications for
interpretation of depleted glacial d13C for this species (Sigman and Boyle,
2000).

Geographic Coverage Spatial coordinates   

Data Set Citation

Dataset Creator: King, A.L. and W.R. Howard Dataset Title: Southern Ocean Sediment Trap Planktonic Foraminiferal d18O Data Dataset Series Name: IGBP PAGES/WDCA CONTRIBUTION SERIES NUMBER: 2005-050 Dataset Release Date: 7/2005 Dataset Release Place: Boulder CO Dataset Publisher: IGBP PAGES/World Data Center for Paleoclimatology Issue Identification: 2005-050 Online Resource: ftp://ftp.ncdc.noaa.gov/pub/data/paleo/paleocean/by_contributor/kin...

Temporal Coverage

Start Date: 1996-09-22 Stop Date: 1999-02-13

Location Keywords

OCEAN > SOUTHERN OCEAN GEOGRAPHIC REGION > POLAR

Science Keywords

PALEOCLIMATE > OCEAN/LAKE RECORDS > ISOTOPES PALEOCLIMATE > OCEAN/LAKE RECORDS > OXYGEN ISOTOPES PALEOCLIMATE > OCEAN/LAKE RECORDS > SEDIMENTS PALEOCLIMATE > OCEAN/LAKE RECORDS > MICROFOSSILS BIOLOGICAL CLASSIFICATION > PROTISTS > AMOEBOIDS > FORAMINIFERS

ISO Topic Category

GEOSCIENTIFIC INFORMATION

Project

PAGES > Past Global Changes, IGBP

Ancillary Keywords

Oxygen Isotopes Sediments d18O

Data Set Progress

COMPLETE

Originating Center

NOAA/NCDC

Data Center

World Data Center for Paleoclimatology, Boulder Data Center URL: http://www.ncdc.noaa.gov/paleo/ Data Center Personnel Name: WDC/PALEOCLIMATOLOGY, BOULDER Phone: +1 (303) 497-6160 Fax: +1 (303) 497-6513 Email: paleo at noaa.gov Contact Address: World Data Center for Paleoclimatology NOAA/NCDC Code E/GCx3 325 Broadway City: Boulder Province or State: CO Postal Code: 80303 Country: USA

Distribution

Distribution Media: ftp Distribution Format: text, excel Fees: none

Personnel

ALEXANDRIA L. KING (POST) Role: INVESTIGATOR Contact Address: Geoscience Australia City: Canberra Country: Australia W. R. HOWARD Role: INVESTIGATOR

Related URL

Link: GET DATA Link: GET DATA Description: Access to data and documentation

Publications/References
King, A.L. and Howard, W.R. 2005. d18O seasonality of planktonic foraminifera
from Southern Ocean sediment traps: Latitudinal gradients and implications for
paleoclimate reconstructions. Marine Micropaleontology. 56:1-24.

Creation and Review Dates

DIF Creation Date: 2006-12-01 Last DIF Revision Date: 2006-12-20

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