NOAA National Environmental Satellite, Data, and Information Service National Climatic Data Center, U.S. Department of Commerce
NOAA Paleoclimatology Program, NCDC Paleoclimatology Branch
 
Paleoclimatology Navigation Bar Bookmark and Share
NOAA National Environmental Satellite, Data, and Information Service National Oceanic and Atmospheric Administration NOAA National Climatic Data Center U.S. Department of Commerce Paleo Home Data Paleo Perspectives Education and Outreach About Paleo Program Site Map
PALEOCEANOGRAPHY

Southern Ocean Middle Eocene to Early Oligocene Paleoceanographic Data

Map of data site
Anderson, L.D. and M.L. Delaney. 2005. Middle Eocene to early Oligocene paleoceanography from Agulhas Ridge, Southern Ocean (Ocean Drilling Program Leg 177, Site 1090). Paleoceanography 20, 1013.
Data Coverage North: -42.92 * South: -42.92
West: 8.9 * East: 8.9
Altitude: -3698 m

Start Year: 40589788 14C yr BP * End Year: 33065034 14C yr BP

Data:     Please Cite Data Contributors!
  anderson2005
  odp1090-tab.txt

Summary:

Ocean Drilling Program (ODP) Site 1090, on the Agulhas Ridge in the South Atlantic sector of the Southern Ocean, is ideally located to capture changes in Southern Ocean circulation patterns. Using samples taken from cored sediments, we construct multiproxy records of productivity (biogenic barium (Baex), opal, and CaCO3 mass accumulation rates (MARs)), nutrient and organic carbon burial (reactive phosphorus (Pr) MARs), and redox conditions (U and Mn enrichments) to investigate hydrographic conditions associated with climatic shifts from the Oligocene through the early Miocene. Orbitally induced cyclicity in U and Mn enrichments (100 kyr) suggests shifts in deepwater characteristics. However, CaCO3 dissolution coincident with low U and Mn enrichments does not indicate low-oxygen, corrosive waters similar to modern conditions. These observations indicate that a well developed "modern-type" Antarctic Circumpolar Current (ACC) did not yet exist over the period from 30 to 20 Ma, with two potential consequences: The Southern Ocean was not functioning as a silica trap, permitting a broader distribution of silica that may have facilitated organic carbon burial in the ocean in general, and the lack ofa deeply mixing ACC may have facilitated organic carbon burial in the Southern Ocean. Both the relative (high opal MARs coincident with low CaCO3 MARs) and absolute (high Pr MARs) burial of organic carbon suggest a powerful mechanism for pCO2 drawdown.
More Info on Paleoceanography Data

Parameters:

Aluminum ppm; Depth below surface (cm); radiocarbon years before 1950AD; Phosphorus (reactive) concentration mass accumulation rate; Calcium carbonate mass accumulation rate (mmol/cm^2*kyr); Barium (µmol/g); Barium excess (µmol/g); Silicon oxide weight percent; Calcium carbonate weight percent; Titanium (µmol/g); Phosphorus (detrital) concentration (µmol/g); Detrital weight percent; Aluminum/Titanium ratio; Phosphorus (reactive) concentration (µmol/g); Barium excess (µmol) mass accumlation rate (µmol/cm^2*kyr); Opal mass accumulation rate (mmol/cm^2*kyr); Calcium concentration (mmol/g); Uranium concentration (nmol/g); Manganese (µmol/g); Phosphorus (total digestion) concentration (µmol/g)

Complete XML Record:

noaa-ocean-2627  (Last Revised: 2008-04-10 )

NOAA logo DOC/NOAA/NESDIS/NCDC (National Climatic Data Center, NESDIS, NOAA, U.S. Department of Commerce )
325 Broadway, E/CC23
Boulder, CO 80305
USA
http://www.ncdc.noaa.gov/paleo/
E-mail: bruce.a.bauer@noaa.gov
E-mail: paleo@noaa.gov
Phone: 303-497-6280
Fax: 303-497-6513