What radiometric dating technique is used to date volcanic rock
Yet the RATE research has uncovered much evidence, including the patterns of these discordances between the "dates" from the different radioisotope systems, For example, if accelerated radioisotope decay occurred, then alpha-decaying radioisotopes would yield older isochron "ages" than beta-decaying radioisotopes, which is exactly the pattern in the Brahma amphibolites (see diagram above).Because the different radioisotopes are dating the same geologic event, to have produced different "dates" has to mean that the parent radioisotopes have decayed at different rates over the same time period.Most people believe that when the different radioisotope dating methods are used on the same rock unit they all yield the same age.However, the radioisotope dating of these Grand Canyon rocks clearly demonstrates that the disagreement, or isochron discordance, is pronounced.And the K-Ar model "ages" are so widely divergent from one another (ranging from 405.1±10 Ma to 2574.2±73 Ma), even from very closely spaced samples from the same outcrop of the same original lava flow, as to be useless for "dating" any event.These discordant results could easily be dismissed as an isolated aberration, perhaps due to the uncertain effects of metamorphism and any subsequent alteration, especially during erosion and weathering.Irreconcilable disagreement within and between the methods is the norm, even at the outcrop scale.This is a devastating "blow" to the long ages that are foundational to uniformitarian geology and evolutionary biology.
Among these metamorphosed volcanic strata are amphibolites, belonging to the Brahma Schist.
In other words, the decay of the parent radioisotopes was accelerated by different amounts, the decay of those yielding older "ages" (the alpha-decayers) having been accelerated more.
Obviously, if radioisotope decay was accelerated, say during the Genesis Flood, then the radioisotope decay "clocks" could never be relied upon to "date" rocks as many millions of years old.
The "age" or "date" is calculated from the amount of the daughter isotope produced by radioactive decay of the parent isotope.
In Grand Canyon, the "date" of metamorphism of the basalt lavas to form these Brahma amphibolites has been determined as 1690-1710 Ma (million years ago), based on U-Pb dating of minerals in the overlying Vishnu Schist and underlying Rama Schist that formed during the metamorphism.
Search for what radiometric dating technique is used to date volcanic rock:
Even when the calculated error margins are taken into account the different radioisotope dating methods yield completely different "ages" that cannot be reconciled—1240±84 Ma (Rb-Sr), 1655±40 Ma (Sm-Nd), and 1883±53 Ma (Pb-Pb) (see diagram).