New facies analysis of sections in the USA and Europe (France, Germany, Poland), and comparison with sections known from the literature in Canada, Australia and China reveal several high-frequency relative sea-level changes in the late Frasnian to earliest Famennian extinction interval. Geological Society of America Bulletin 96, 567–587) eustatic curve. Geological Society of America Bulletin 96, 567–587) original transgression-anoxia–extinction link is thus supported, although some extinction losses of platform carbonate biota during the preceeding regression cannot be ruled out. This cause-and-effect nexus has been accepted by many but others prefer sea-level fall and cooling as an extinction mechanism.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.
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.These two independent and agreeing dating methods for of the age of two primary members of the solar system formed a strong case for the correctness of his answer within the scientific community.This just goes to show that just because independent estimates of age seem to agree with each other doesn't mean that they're correct - despite the fact that this particular argument is the very same one used to support the validity of radiometric dating today.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.