(Table 1) U and Th isotopic composition and 230Th ages of samples from the A1 and C1 corals of Legare Anchorage


The 14C reservoir age of the surface ocean was determined for two Holocene periods (4908-4955 and 3008-3066 calendar (cal) B.P.) using U/Th-dated corals from Biscayne National Park, Florida, United States. We found that the average reservoir ages for these two time periods (294 ± 33 and 291 ± 27 years, respectively) were lower than the average value between A.D. 1600 and 1900 (390 ± 60 years) from corals. It appears that the surface ocean was closer to isotopic equilibrium with CO2 in the atmosphere during these two time periods than it was during recent times. Seasonal d18O measurements from the younger coral are similar to modern values, suggesting that mixing with open ocean waters was indeed occurring during this coral's lifetime. Likely explanations for the lower reservoir age include increased stratification of the surface ocean or increased D14C values of subsurface waters that mix into the surface. Our results imply that a more correct reservoir age correction for radiocarbon measurements of marine samples in this location from the time periods ~3040 and ~4930 cal years B.P. is ~292 ± 30 years, less than the canonical value of 404 ± 20 years.

AGE [ka BP] presents the corrected Th age before 2007.

Supplement to: Druffel, Ellen RM; Robinson, Laura F; Griffin, Sheila; Halley, Roberet B; Southon, John R; Adkins, Jess F (2008): Low reservoir ages for the surface ocean from mid-Holocene Florida corals. Paleoceanography, 23(2), PA2209

DOI https://doi.org/10.1594/PANGAEA.832370
Related Identifier https://doi.org/10.1029/2007PA001527
Metadata Access https://ws.pangaea.de/oai/provider?verb=GetRecord&metadataPrefix=datacite4&identifier=oai:pangaea.de:doi:10.1594/PANGAEA.832370
Creator Druffel, Ellen RM ORCID logo; Robinson, Laura F ORCID logo; Griffin, Sheila; Halley, Roberet B; Southon, John R; Adkins, Jess F ORCID logo
Publisher PANGAEA
Publication Year 2008
Rights Creative Commons Attribution 3.0 Unported; https://creativecommons.org/licenses/by/3.0/
OpenAccess true
Language English
Resource Type Supplementary Dataset; Dataset
Format text/tab-separated-values
Size 170 data points
Discipline Earth System Research
Spatial Coverage (-80.142 LON, 25.483 LAT); Florida shelf