As further discussed in Dalrymple and Lanphere (1969, p. 91-92), Dalrymple concludes that excess argon is rare in volcanic rocks. B., 1991, The Age of the Earth, Stanford University Press, Stanford, California, USA. In addition, excess argon is even less of a problem with Ar-Ar dating, where excess argon can often be distinguished from radiogenic argon and its effects eliminated (Mc Dougall and Harrison, 1999, p. , Snelling failed to properly quote the 'apparent K-Ar dates' from Table 2 in Dalrymple (1969, p. That is, Snelling mistakenly listed the concentrations of 40Ar (in 10 to the -12 moles/gram) for the Hualalai, Mt. Lassen, and Sunset Crater samples as their apparent K-Ar dates!! Thus Dalrymple’s data is not consistent with a young Earth whatsoever. Indeed, if Dalrymple’s data is representative, 3 times out of 26 the K-Ar method will give a too young date (though by only an extremely trivial amount for a rock that is really millions of years old). Rather than checking the accuracy and relevancy of Austin's quotations from Dalrymple (1969), Snelling and Swenson simply uncritically parroted and perpetuated Austin's mistakes in their later web essays. This is truly a case of the blind leading the blind!! B., 1969, '40Ar/36Ar Analyses of Historic Lava Flows,' Earth Planet.
And in 25 times out of 26 tests there is no excess argon or there is so little excess argon that it will make only a tiny error, if any, in the final date for rocks millions of years old. Of the 26 lava flows that were sampled and analyzed, 18 of them gave expected results. Eight rocks yielded unrealistic dates, which were either too old because of the presence of excess 40Ar (5 of them) or too young (negative ages) because of the presence of excess 36Ar (3 of them). The details on the 8 anomalous samples are listed in Table 2 of Dalrymple (1969, p. In particular, YECs attempt to demonstrate that excess argon is a 'problem' for K-Ar dating by locating examples of historically erupted volcanics, which yield K-Ar dates that are hundreds of thousands or millions of years older than their eruption dates. Brent Dalrymple is a geochronologist with 40 years experience, a pioneer in the identification of excess argon in igneous samples, and an outspoken critic of young-Earth creationism (e.g., Dalrymple, 1984). As part of his seminal work on excess argon, Dalrymple (1969) dated 26 historical lava flows with K-Ar to determine whether excess argon was present. Etna basalts (a 'date' of 150,000 years for a sample that erupted in 1792 AD and a K-Ar 'date' of 100,000 years for the other sample, which erupted in 122 BC), a plagioclase from Mt.