Vanuatu Fossil Coral Sea Surface Temperature Reconstruction for 4200 YrBP: readme file
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               World Data Center A- Paleoclimatology
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NOTE: PLEASE CITE CONTRIBUTORS WHEN USING THIS DATA!!!!!


NAME OF DATA SET: Vanuatu Fossil Coral SST Reconstruction for 4200 YrBP
LAST UPDATE: 9/00 (Original Receipt by WDCA Paleo)  

CONTRIBUTORS: Thierry Correge, Thierry Delcroix, Jacques Recy, Warren Beck, 
Guy Cabioch, and Florence Le Cornec.

IGBP PAGES/WDCA CONTRIBUTION SERIES NUMBER:  2000-060

SUGGESTED DATA CITATION: Correge, T., et al., 2000,
Vanuatu Fossil Coral SST Reconstruction for 4200 YrBP,
IGBP PAGES/World Data Center-A for Paleoclimatology Data 
Contribution Series # 2000-060.  
NOAA/NGDC Paleoclimatology Program, Boulder CO, USA.

ORIGINAL REFERENCE: Correge, T., Delcroix, T., Recy, J., Beck, W.,
Cabioch, G., and Le Cornec, F., 2000, Evidence for stronger El Nino-
Southern Oscillation (ENSO) events in a mid-Holocene massive coral. 
Paleoceanography, 15(4), 465-470

GEOGRAPHIC REGION: Vanuatu, western equatorial Pacific.
PERIOD OF RECORD:  47-year floating series at ~4200 Years Before Present.

LIST OF FILES: Readme.Vanuatu.4200BP.txt (this file), 
vanuatu.4200bp.sst.txt, (contains month number and 
Sea Surface Temperature in degrees C), 
vanuatu.4200bp.SrCaU.txt.

FUNDING SOURCE: Institut de Recherche pour le Developpement, France

DESCRIPTION: 
Vanuatu Fossil Coral SST Reconstruction, 4200 YrBP.

Latitude: 15 40'S
Longitude: 167 00'E
Paleobathymetry estimated at 10-15 m.

SST reconstruction is based on the analysis of Sr/Ca and U/Ca ratios 
in corals. For the present study, precision on the Sr/Ca paleothermometer 
was 1.3 deg C, and 0.9 deg C for the U/Ca paleothermometer. 

The data consist of reconstructed Sea Surface Temperatures extrapolated from analyses 
of trace element ratios in a fossil coral head. A date of 4166 15 calendar yr BP was 
obtained by the U/Th series technique for the coral. This date corresponds to the 
cold episode centered around sample #464. 

A fossil coral from Tasmaloum (Vanuatu) was found between 0.80 and 1.20 m depth in 
drill core 9A, collected at an altitude of +4.66 m above sea level. Owing to the 
calculated uplift rate the paleodepth of the Porites can be estimated ~10-15 m. at 
4150 years B.P.  The surrounding coral assemblages indicate an open shallow marine 
environment. Sr/Ca and U/Ca analyses were converted to SST, 
using the following equations:

Sr/Ca (10-3 M) = 10.73 - 0.0657SST    R = 0.79
U/Ca  (10-6 M) = 2.106 - 0.0367SST    R = 0.89

In > 98% of the samples analyzed, Sr and U reconstructed SST agree well within error. 
A 47-year-long composite SST curve was then constructed, and monthly SST values were 
extrapolated. 

File vanuatu.4200bp.SrCaU.txt:
Raw Sr/Ca and U/Ca data.
- sample #1 is the youngest, i.e. the one with an estimated age of 412815 BP.
- there are some data missing. For U/Ca, it is due to the sample size. 
When it is too small, we cannot measure U accurrately, and although we got U values, 
they usually have a %RSD attached to them which is higher than 1%, 
and I don't feel they are precise enough to be used. 
For Sr/Ca, we experienced several problems with our machine. 
When the Sr data looked dubious (i.e. when we had poor stability in the in-house 
coral standard we analyze during each run) we re-ran the Sr and Ca analyses. 
In most cases, the two runs agreed within error. When there was a discrepancy 
between the two runs, we ran the samples a third time (when sample size permitted). 
Missing Sr/Ca data are those samples too small to allow for a third run.
These are raw data. They were then translated into temperature data using the 
equations presented in the article, averaged and resampled at monthly interval 
using the Analyseries program.