Radiometric dating of the earth
For example, Henry Morris says: He lead to similar results, i.e., a rate virtually identical to the estimated production flux.
If the solar system formed from a common pool of matter, which was uniformly distributed in terms of Pb isotope ratios, then the initial plots for all objects from that pool of matter would fall on a single point.The most direct means for calculating the Earth's age is a Pb/Pb isochron age, derived from samples of the Earth and meteorites.This involves measurement of three isotopes of lead (Pb-206, Pb-207, and either Pb-208 or Pb-204).And from the slope of the line we can compute the amount of time which has passed since the pool of matter became separated into individual objects.See the Isochron Dating FAQ or Faure (1986, chapter 18) for technical detail.The higher the uranium-to-lead ratio of a rock, the more the Pb-206/Pb-204 and Pb-207/Pb-204 values will change with time.
If the source of the solar system was also uniformly distributed with respect to uranium isotope ratios, then the data points will always fall on a single line.
) and they are historically the ones posted to talk.origins more than any others.
The young-Earth argument goes something like this: helium-4 is created by radioactive decay (alpha particles are helium nuclei) and is constantly added to the atmosphere.
Over time, the amounts of Pb-206 and Pb-207 will change in some samples, as these isotopes are decay end-products of uranium decay (U-238 decays to Pb-206, and U-235 decays to Pb-207).
This causes the data points to separate from each other.
A young-Earther would object to all of the "assumptions" listed above.