Considering that the half-life of potassium-40 (40K) is fairly long (1,250 million years, McDougall and Harrison, 1999, p. 9), the K-Ar method cannot be used to date samples that are much younger than 6,000 years old (Dalrymple, 1991, p. 93). A few thousand years are not enough time for 40Ar to accumulate in a sample at high enough concentrations to be detected and quantified. Furthermore, many geochronology laboratories do not have the expensive state-of-the-art equipment to accurately measure argon in samples that are only a few million years old. Specifically, the laboratory personnel that performed the K-Ar dating for Austin et al. Specifically, personnel at Geochron Laboratories of Cambridge, Massachusetts, USA, performed the K-Ar dating for Austin et al. This laboratory no longer performs K-Ar dating. However, when they did, their website clearly stated in a footnote that their equipment could not accurately date rocks that are younger than about 2 million years old (“We cannot analyze samples expected to be younger than 2 M.Y.”; also see discussions by Bartelt et al.). With less advanced equipment, ‘memory effects’ can be a problem with very young samples (Dalrymple, 1969, p. 48). That is, very tiny amounts of argon contaminants from previous analyses may remain within the equipment, which precludes accurate dates for very young samples. For older samples, which contain more 40Ar, the contamination is diluted and has insignificant effects. Considering the statements at the Geochron website and the lowest age limitations of the K-Ar method, why did Austin submit a recently erupted dacite to this laboratory and expect a reliable answer??? Contrary to Swenson’s uninformed claim that ’ Dr Austin carefully designed the research to counter all possible objections’, Austin clearly demonstrated his inexperience in geochronology when he wasted a lot of money using the K-Ar method on the wrong type of samples.
