Potassium argon dating is only done with
However, rather than dealing with this issue and critically evaluating Austin's other procedures (including the unacceptable mineral and glass impurities in his 'fractions'), YECs loudly proclaim that the results are discrepant with the 1986 AD eruption.
Considering that the dacite probably erupted in 1986 AD, Austin should have known that at least some of the samples would have given dates that were younger than 2 million years old and that Geochron Laboratories could not have provided reliable answers.
This preparation is the purest mineral concentrate.'However, because Austin ignores the analytical inadequacies of Geochron's mass spectrometer (hypothesis #2), except for possibly the pyroxenes, there is no evidence that excess argon is present in any of the other mineral or glass components in this sample.'Another critic said that Dr Austin should only have dated the volcanic glass from his sample, because the glass would have solidified when the lava dome formed.
However, Dalrymple  found that even volcanic glass can give wrong ages and rationalized that it can be contaminated by argon from older rock material.'Clearly, Swenson simply assumes that the volcanic glass contains 'excess argon.' However, dating a mixture of older plagioclase and younger volcanic glass with inadequate equipment (hypothesis #2) does not prove that any of these components contain excess argon.
Furthermore, many studies (for example, the Haulalai basalt; Funkhouser and Naughton, 1968) demonstrate that Swenson and other YECs cannot automatically assume that modern volcanic glass contains excess argon.
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.
Specifically, Austin admits that most of his fractions are impure when he includes the term 'etc.' after most of the mineral 'fractions' in his table (see above).'Although NOT a complete separation of non-mafic minerals, this concentrate included plagioclase phenocrysts (andesine composition with a density of about 2.7 g/cc) and the major quantity of glass (density assumed to be about 2.4 g/cc).
These mafic microphenocrysts and fragments of mafic phenocrysts evidently increased the density of the attached glass particles above the critical density of 2.85 g/cc, which allowed them to sink in the heavy liquid. Zoned crystals also may show Carlsbad twinning, which is typical of feldspars (Perkins and Henke, 2000, Plate 10; Klein and Hurlbut, 1999, p. Well-established laboratory studies (Klein and Hurlbut, 1999, p. 86-89) indicate that calcium-rich plagioclases crystallize in melts at higher temperatures than albite or sodium-rich plagioclases.