Pb pb isochron dating dating site in paris
Meteorites date the earth with a 4.55 ± 0.07 Ga Pb-Pb isochron called the geochron. They appear to consistently yield 4.55–4.57 Ga radioisotope ages, adding to the uniformitarians’ confidence in the radioisotope dating methods. At t=0, the equation for radiogenic Pb isotopes is indeterminate since it results in division by 0.Secular scientists get around this problem by a clever application of l’Hôpital’s rule to estimate that the original ratio is (Pb)* = 0.04604.Radiometric dating has now been used for almost 50 years to establish “beyond doubt” the earth’s multibillion year geological column.Although this column and its “age” was firmly settled well before the advent of radiometric dating, the latter has been successfully used to help quantify the “ages” of the strata and the fossils in the column, so that in many people’s minds today radiometric dating has “proved” the presumed antiquity of the earth.This paper was originally published in the Proceedings of the Third International Conference on Creationism, pp.497–504 (1994) and is reproduced here with the permission of the Creation Science Fellowship of Pittsburgh.
We further conclude that nebular chondrules dated by the Pb–Pb method require that they formed contemporaneously with CAIs and continued to form for at least ∼4 Myr, a conclusion that implies heterogeneous distribution of the short-lived Al nuclide in the protoplanetary disk.
There is also scattering of many Rb-Sr, Lu-Hf, Re-Os, Sm-Nd isochron ages, and a few Pb-Pb isochron ages, in most cases likely due to thermal disturbances resulting from impact cratering of the parent asteroids.
No pattern was found in the isochron ages for these groups of meteorites similar to the systematic patterns of isochron ages found in Precambrian rock units during the RATE project, so there is no evidence of past accelerated radioisotope decay having occurred in these meteorites, and therefore on their parent asteroids. “Sm-Nd Isotopic Evolution of Chondrites and Achondrites, II.” Earth and Planetary Science Letters 67 (2): 137–50.
This method reaches the pinnacle of radioisotope dating methods in terms of complication and convolution.
Since we do not want to be tossed to and fro by every teaching that cunning men put in front of us, let’s carefully investigate this method’s viability as a reliable clock for terrestrial and extraterrestrial rock formations.
Even a claimed near-concordant U-Pb ‘age’ of 862 Ma on one uraninite grain is identical to a false Pb-Pb isochron “age,” but neither can be connected to any geological event.