No wonder the laboratories that “date” rocks insist on knowing in advance the “evolutionary age” of the strata from which the samples were taken—this way, they know which dates to accept as “reasonable” and which to ignore.
Of one thing you may be sure: whenever “absolute” radiometric dates are in substantial disagreement with evolutionary assumptions about the age of associated fossils, the fossils always prevail.
Much of the controversy between evolutionists and creationists concerns the age of the earth and its fossils.
At the time Darwin’s On the Origin of Species was published, the earth was “scientifically” determined to be 100 million years old. In 1947, geologists firmly established that the earth was 3.4 billion years old.
The most commonly used radiometric methods for “dating” geological specimens are potassium-argon, uranium-thorium-lead, and strontium-rubidium.
All three of these decay processes have half-lives measured in billions of years.
None of these methods can be used directly on fossils or the sedimentary rock in which fossils are found.
All radiometric dating (with the exception of carbon dating) must be done on igneous rocks (rocks solidified from a molten state such as lava).The problem with all radiometric “clocks” is that their accuracy critically depends on several starting assumptions that are largely unknowable.To date a specimen by radiometric means, one must first know the starting amount of the parent isotope at the beginning of the specimen’s existence.The most widely used method for determining the age of fossils is to date them by the “known age” of the rock strata in which they are found.On the other hand, the most widely used method for determining the age of the rock strata is to date them by the “known age” of the fossils they contain. O’Rourke, for example, concedes: The intelligent layman has long suspected circular reasoning in the use of rocks to date fossils and fossils to date rocks.Second, one must be certain that there were no daughter isotopes present in the beginning.