High Resolution Stable Isotopic Data from Ceara Rise: Readme file
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              World Data Center for Paleoclimatology, Boulder
                                and 
                   NOAA Paleoclimatology Program
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NOTE: PLEASE CITE ORIGINAL REFERENCE WHEN USING THIS DATA!!!!!

NAME OF DATA SET: High Resolution Stable Isotopic Data from Ceara Rise

LAST UPDATE: 4/2000 (Original Receipt by WDCA Paleo)  
CONTRIBUTOR: W. B. Curry, Woods Hole Oceanographic Institution

IGBP PAGES/WDCA CONTRIBUTION SERIES NUMBER: 2000-030

SUGGESTED DATA CITATION: Curry, W. B. and D. W. Oppo, 2000, 
High Resolution Stable Isotopic Data from Ceara Rise, 
IGBP PAGES/World Data Center A for Paleoclimatology 
Data Contribution Series #2000-030.
NOAA/NGDC Paleoclimatology Program, Boulder CO, USA. 

ORIGINAL REFERENCE:  Curry, W. B. and D. W. Oppo, 1997, 
Synchronous, high-frequency oscillations in tropical sea surface 
temperatures and North Atlantic Deep Water Production during 
the last glacial cycle, Paleoceanography, v. 12, pp. 1-14, 1997.

GEOGRAPHIC REGION: Ceara Rise, western equatorial Atlantic
PERIOD OF RECORD: 150 KYrBP-Present

LIST OF FILES: Readme.Curry1997.txt (this file),
1JPC_datafile.txt, 1JPC_datafile_revised.txt, jpc1_sac_all.txt,
jpc1_sac.txt, jpc1_cibs_all.txt, jpc1_cibs.txt.

DESCRIPTION: 
High resolution stable isotopic data from Ceara Rise.

Calibration to VPDB
The data are presented with respect to VPDB based on an published values 
for NBS-19 of -2.20 for 18O and 1.95 for 13C.  Since they were first published, 
we have undertaken an extensive intercalibration of our laboratory with a large 
segment of the paleoceanography research community.  The results of this 
intercalibration are published in:

Ostermann, D. R. and W. B. Curry, Calibration of stable isotope data: 
An enriched 18O standard used for source gas mixing detection and correction, 
Paleoceanography, v. 15, pp. 353-360, 2000.

As a result of this intercalibration, we discovered that our original data needed 
a small revision.  Thus we provide here both the original data as published, 
and the revised data based on our further evaluations of mass spectrometer performance.  
The differences between the data sets are small (<0.05 permil for 13C and <~0.1 permil 
for 18O for the planktonic foraminifera, ~0.15 to 0.2 permil for the benthic foraminifera), 
but large enough to warrant recalculation.  The corrections are also dependent on sample 
size and isotopic composition, so it is not possible to subtract a constant from the 
original to obtain the revised data.  It is this revised data that we recommend be used 
by interested researchers.
  
There are six files in the data set:

1JPC_datafile.txt:  Complete, original published stable isotope data set.

Column 1:  Core label
Column 2:  taxonomic label (genus)
Column 3:  taxonomic label (species)
Column 4:  Depth in core (cm)
Column 5:  13C with respect to VPDB 
Column 6:  18O with respect to VPDB


1JPC_datafile_revised.txt:  Complete stable isotope data set, with revised 
conversions to VPDB based on the interlaboratory calibration outlined in 
Ostermann, D. R. and W. B. Curry, Calibration of stable isotope data: 
An enriched 18O standard used for source gas mixing detection and correction, 
Paleoceanography, v. 15, pp. 353-360, 2000.

Column 1:  Core label
Column 2:  taxonomic label (genus)
Column 3:  taxonomic label (species)
Column 4:  Depth in core (cm)
Column 5:  13C with respect to VPDB 
Column 6:  18O with respect to VPDB


jpc1_sac.txt:  File containing all original (as published) 
G. sacculifer isotope data, including all samples measured at each stratigraphic level.

Column 1:  Depth in core (m)
Column 2:  Age (ka) using the published chronology
Column 3:  13C with respect to VPDB
Column 4:  18O with respect to VPDB


jpc1_sac.txt:  File containing original (as published) averaged 
G. sacculifer isotope data at each stratigraphic level.

Column 1:  Depth in core (m)
Column 2:  Age (ka) using the published chronology
Column 3:  13C with respect to VPDB
Column 4:  18O with respect to VPDB


jpc1_cibs_all.txt:  File containing all original (as published) 
C. wuellerstorfi and C. spp. isotope data, including all samples measured at 
each stratigraphic level.

Column 1:  Depth in core (m)
Column 2:  Age (ka) using the published chronology
Column 3:  13C with respect to VPDB
Column 4:  18O with respect to VPDB


jpc1_cibs.txt:  File containing original (as published) averaged 
C. wuellerstorfi and C. spp. isotope data at each stratigraphic level.

Column 1:  Depth in core (m)
Column 2:  Age (ka) using the published chronology
Column 3:  13C with respect to VPDB
Column 4:  18O with respect to VPDB