Of course, later scientists, like John Perry and T. After this came to light, Kelvin admitted that he might just as well have set his original upper limit on the age of the Earth at 4,000 Ma instead of 400 Ma.
Of course, this was a close as Kelvin ever came to publicly recanting his position.
There is perhaps no beguilement more insidious and dangerous than an elaborate and elegant mathematical process built upon unfortified premises." - Chamberlain 1899b:224Following the discovery of radioactivity by Becquerel (1896), the possibility of using this phenomenon as a means for determining the age of uranium-bearing minerals was demonstrated by Rutherford (1906).
One year later Boltwood (1907) developed the chemical U-Pb method. By combining Von Weizsacker’s argon abundance arguments with Kohlhorster’s observation that potassium emitted gamma-radiation, Bramley (1937) presented strong evidence that potassium underwent dual decay.
Of course there seem to me to be fairly reasonable explanations for this observation which may allow for more slowly forming granitic rocks.
For instance, polonium radiohalos are sometimes associated with polonium bands generated by the polonium being transported by hydrothermal fluids along fractures.Potassium - Argon and Argon - Argon dating are based on the current understanding that radioactive Potassium-40 decays to the stable form, Argon-40 with a half-life of approximately 1.25 billion years.There are some circumstances that can affect this rate such as magnetic fluctuations etc...Based on these assumptions he at first suggested an age of the Earth of between 100 Ma and 500 Ma.This estimate was actually reduced over his lifetime to between 20 Ma and 40 Ma and eventually to less than 10 Ma. Perry, in particular, a noted physicists and former assistant to Kelvin, showed that cooling calculations using different but equally likely assumptions and data resulted in ages for the Earth of as much as 29 Ga." -- John in NC "eliminates awkward first-date conversations about political views!" -- Denise in AR "better than any dating site I've tried. Interweaving the relative time scale with the atomic time scale poses certain problems because only certain types of rocks, chiefly the igneous variety, can be dated directly by radiometric methods; but these rocks do not ordinarily contain fossils.Some, like Robert Gentry, have even argued that Radio-halos from rapidly decaying radioactive isotopes in granite seem to indicate that the granites were formed almost instantly.Many granites that contain polonium radiohalos appear from their geologic contexts to have been formed during the Flood, and therefore cannot have been primordial (that is, created) granites as Gentry has suggested ( Link ).Most sedimentary rocks such as sandstone, limestone, and shale (which do contain fossils) are related to the radiometric time scale by bracketing them within time zones that are determined by dating appropriately selected igneous rocks in lava flows, or weathered from lava flows.