Radiometric dating age of fossils
Furthermore, the seven samples from the small amphibolite unit near Clear Creek, which should all be the same age because they belong to the same metamorphosed basalt lava flow, yielded K-Ar model ages ranging from 1060.4±28 Ma to 2574.2±73 Ma.This includes two samples only 0.84 meters apart that yielded K-Ar model ages of 1205.3±.2±73 Ma.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.The computer program Isoplot was used to plot isochrons and calculate isochron ages from the other radioisotope analyses.The best isochron plots, where all the variation from the line of best fit to the data incorporates all the analytical errors, yielded an Rb-Sr isochron age of 1240±84 Ma, an Sm-Nd isochron age of 1655±40 Ma, and a Pb-Pb isochron age of 1883±53 Ma.However, they are confirmation of the repeated failure of all the radioisotope "dating" methods to successfully date Grand Canyon rocks.but tenuous "explanations" are given to account for the anomalous amounts of daughter products, and avoid the inescapable conclusion that the radioisotope methods simply do not yield reliable absolute ages.
Among these metamorphosed volcanic strata are amphibolites, belonging to the Brahma Schist.
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.
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).
None of the obtained isochron "ages" corresponds to the "date" for any recognized event, neither the original lava eruptions nor the subsequent metamorphism.