| Summary: | The following list includes most of the measurements made since publication of Yale V [GeoScience Abstracts 2-2008]; some measurements, such as a series collected in Greenland by A.L. Washburn, are withheld pending additional information or field work that will make better interpretations possible. In addition to radiocarbon dates of geologic and/or archeologic interest, the third part of the paper gives, for the first time since 1954, recent assays of C (super 14) in lake waters and other lacustrine materials, now normalized for C (super 13) content. Some of these C (super 13) values have been published separately, but most have not. The newly accepted convention (Lamont VIII) is accepted in expressing normalized C (super 14) values as Delta = delta C (super 14) - (2delta C (super 13) + 50) (1 + delta C (super 14) /1000) where Delta is the per mil deviation of the C (super 14) of the sample from any contemporary standard (whether organic or a carbonate) after correction of sample and/or standard for real age, for the Suess effect, for normal isotopic fractionation, and for deviations of C (super 14) content of the age- and pollution-corrected 19th-century wood standard from that of 95% of the NBS oxalic-acid standard; delta C (super 14) is the measured deviation from 95% of the NBS standard, and delta C (super 13) is the deviation (measured on a Consolidated mass-spectrometer, Model 21-401) from the NBS limestone standard, both in per mil. These assays, made in 1958 and later, are of course variously affected by artificial C (super 14) resulting from nuclear tests, and detailed or general comments are withheld until studies have continued for at least another season.
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