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U.S. Geological Survey, Denver, Colorado Radiocarbon Dates I*

Published online by Cambridge University Press:  18 July 2016

L. J. Schroder
Affiliation:
U.S. Geological Survey, Denver Federal Center, Lakewood, Colorado 80225
W. A. Beetem
Affiliation:
U.S. Geological Survey, Denver Federal Center, Lakewood, Colorado 80225
H. C. Claassen
Affiliation:
U.S. Geological Survey, Denver Federal Center, Lakewood, Colorado 80225
R. L. Emerson
Affiliation:
U.S. Geological Survey, Denver Federal Center, Lakewood, Colorado 80225
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The U.S. Geological Survey, at the Denver Federal Center, Lakewood, Colorado assays C14 concentration of water samples using liquid scintillation techniques. The laboratory synthesizes benzene from precipitated barium carbonate using techniques described by Noakes, Kim, and Akers (1967). Three ml of the synthesized benzene is pipetted into a tared, low potassium-40 glass vial. The sample is weighed and 1ml of a scintillation solution is added to the vial. The scintillation solution used is a mixture of 10g PPO and 0.025g dimethyl-POPOP scintillators in 250ml toluene. Calculations of dates are made with the radiocarbon half-life of 5568 years; plus or minus numbers quoted herein are the standard error for the counting of radioactive disintegrations.

Type
Research Article
Copyright
Copyright © The American Journal of Science 

References

Buckley, J. D. and Willis, E. H., 1969, Isotopes' radiocarbon measurements VII: Radiocarbon, v. 11, p. 53105.CrossRefGoogle Scholar
Craig, Harmon, 1957, Isotopie standards for carbon and oxygen and correction factors for mass-spectrometric analysis of carbon dioxide: Geochim. et Cosmochim. Acta, v. 12, p. 133149.CrossRefGoogle Scholar
Noakes, J. E., Kim, S. M., and Akers, L. K., 1967, Recent improvements in benzene chemistry for radiocarbon counting: Geochim. et Cosmochim. Acta, v. 31, p. 10941096.Google Scholar
Rainwater, F. H. and Thatcher, L. L., 1960, Methods for collection and analysis of water samples: U.S. Geol. Survey Water-Supply Paper 1454, p. 9495.Google Scholar