Potassium argon dating is only done with
9), the K-Ar method cannot be used to date samples that are much younger than 6,000 years old (Dalrymple, 1991, p. 93)Cambridge, Massachusetts, USA, performed the K-Ar dating for Austin et al. 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. Mafic microphenocrysts within these glassy particles were probably dominated by the strongly magnetic Fe-Ti oxide minerals.
Although hypothesis #1 is plausible, until the argon isotope concentrations of the PURE glass are accurately measured for Austin's dacite (if this is even possible) we cannot properly evaluate this hypothesis.'The origin of the excess 40Ar is not entirely clear, but the discovery of excess 40Ar in Holocene quenched basalt glass [Dalrymple and Moore, 1968] indicates that radiogenic argon, released when older rocks are heated or melted, is dissolved in the melt and may be occluded by minerals as they crystallize.''Up to 2.6 x 10 to the -11 mole/gram of excess radiogenic 40Ar has been found in SUBMARINE basalts of Holocene age from Kilauea [Dalrymple and Moore, 1968; plus another reference], BUT IT'S OCCURRENCE THERE IS NOT SURPRISING IN VIEW OF THE HYDROSTATIC PRESSURE IN THE OCEAN DEPTHS and the rapidity with which SUBAQUEOUS flows are quenched.' [my emphasis]Although high-pressure ocean water may prevent argon gas from escaping from the rims of a lava flow on the ocean floor, the centers of modern submarine flows typically provide K-Ar dates of 'zero years' (Young, 1982, p. While YECs explain geology by invoking talking snakes, magical fruit, and a mythical 'Flood', Dalrymple (1969) discusses legitimate chemistry and fluid physics, which is hardly relying on flimsy 'rationalizations' or implausible excuses.'With the exception of the Hualalai flow [which contains noticeable ultramafic xenoliths, Dalrymple, 1969, p.
Y."; also see discussions by advanced equipment, 'memory effects' can be a problem with very young samples (Dalrymple, 1969, p. That is, very tiny amounts of argon contaminants from previous analyses may remain within the equipment, which precludes accurate dates for very young samples.