Illinois State Geological Survey Radiocarbon Dates I
Bibliographic Data
| ID | 9241934 |
|---|---|
| Authors | Stephen M Kim, R R Ruch |
| Year | 1969 |
| Volume | 11 |
| Issue | 2 |
| Pages | 394-395 |
| Publication date | 1969-01-01 |
| Open Access | Yes |
| Type | ARTICLE |
| Venue | Radiocarbon (JOURNAL) |
| Journal identifiers | ISSN: 0033-8222 • E-ISSN: 1945-5755 |
| Publisher | Cambridge University Press (CUP) (PUBLISHER) |
| DOI | 10.1017/s0033822200011292 |
| OpenAlex | W4231913050 |
| Language | EN |
| Citations received | 5 |
| References cited | 3 |
The radiocarbon dating laboratory of the Illinois State Geological Survey has been established to satisfy a growing need for radiocarbon dates for an active Pleistocene research program. Because of the age and type of material dated, the benzene liquid scintillation counting method is employed in this laboratory. The detailed chemical procedure for converting carbon to benzene has been published by Noakes, Kim, and Stipp (1965) and Noakes, Kim, and Akers (1967); however, the procedures for benzene synthesis and sample counting are briefly explained below to clarify this laboratory's procedure. An organic sample, such as peat, organic silt, or wood, is burned and the CO 2 evolved is absorbed in NH 4 OH. SrCl 2 solution is added to precipitate the carbonate, and the solution plus precipitate is boiled and cooled before filtration of SrCO 3 . The SrCO 3 is acidified with dilute H 3 PO 4 to liberate CO 2 in a closed system, and the CO 2 is converted to C 2 H 2 , as reported by Barker (1953). In this method, 2.4 gm of dry packed lithium, obtainable from the Lithium Corporation of America, is used for each liter of CO 2 that is converted to C 2 H 2 . Trimerization of the C 2 H 2 to form C 6 H 6 is accomplished using a vanadium-alumina catalyst. To the C 6 H 6 synthesized from the sample carbon, 2 cc of toluene containing 100 mg Butyl-PBD, 2-(4-tert-Butylphenyl)-5-(4-Biphenylyl)-1,3,4-Oxadiazole, are added, and this mixture is made to a total volume of 10 cc with spectrograde C 6 H 6 . A modified Packard Instrument Co. liquid scintillation spectrometer (Model 3375) is used for measurement of C 14 activity. Ages are calculated from a C 14 half-life of 5568 years, and the standard deviation (1σ) is based only on counting errors; however, if calculated error is less than 200 years, 200 years is chosen as one standard deviation (1σ)
Archaeology · Benzene · Carbon fibers · Carbon-14 · Carbonate · Geography · Liquid scintillation counting · Mineralogy · Nuclear chemistry · Peat · Radiocarbon dating · Radiochemistry · Toluene · Chemistry · Geochemistry and Geologic Mapping · Geology and Paleoclimatology Research · Isotope Analysis in Ecology · Materials Science · Geology · Organic Chemistry
| Citations per year | 0.09 |
|---|---|
| Citation span | 1970 - 1977 (8) |
| Highly cited | No |