Old Carbon Project

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"Accelerator mass spectrometry (AMS) was first developed in 1977 as a way todirectly measure the ratio of radiocarbon (carbon-14) to stable carbon(carbon-12) in organic material and thus to determine when the organism diedusing samples of a milligram or less. For reasons that are not completelyunderstood the technique is presently limited to samples that are 60,000years old or younger. Even for samples, e.g. carbon from oil, natural gas(methane) or coal, that are millions of years old this limit applies. Itthus prevents the dating of very old samples. It also prevents theselection of sources of natural gas for use in the production of very largevolume liquid scintillation detectors for the measurement of low energyneutrinos. The measurement of these and higher energy neutrinos from thesun is presently an important scientific endeavor. One would like to findsources of methane that have carbon-14 to stable carbon ratios correspondingto 110,000 years, or, perhaps, even to 150,000 years from whichscintillation liquid can be manufactured to allow the measurement of thelowest energy solar neutrinos. The proposed research has the aim ofmeasuring such ages of methane and other organic material by AMS."