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.
was published, the earth was "scientifically" determined to be 100 million years old. In 1947, science firmly established that the earth was 3.4 billion years old.
Finally in 1976, it was discovered that the earth is "really" 4.6 billion years old… The answer of 25 million years deduced by Kelvin was not received favorably by geologists.
Without this knowledge, he argued that, "As for the future, we may say, with equal certainty, that inhabitants of the Earth cannot continue to enjoy the light and heat essential to their life, for many million years longer, unless sources now unknown to us are prepared in the great storehouse of creation."The same is true of the basis of Kelvin's estimate of the age of the Earth.
The solar estimate was based on the idea that the energy supply for the solar radioactive flux is gravitational contraction.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.Chamberlain (1899) pointed out that Kelvin's calculations were only as good as the assumptions on which they were based."The fascinating impressiveness of rigorous mathematical analyses, with its atmosphere of precision and elegance, should not blind us to the defects of the premises that condition the whole process.Other factors and basic assumptions must also be considered.