If it sounds like circular reasoning, it is because this process in reality is based upon circular reasoning.
When scientists first began to compare carbon dating data to data from tree rings, they found carbon dating provided "too-young" estimates of artifact age.
Scientists now realize that production of carbon-14 has not been constant over the years, but has changed as the radiation from the sun has fluctuated.
Nuclear tests, nuclear reactors and the use of nuclear weapons have also changed the composition of radioisotopes in the air over the last few decades.
This human nuclear activity will make precise dating of fossils from our lifetime very difficult due to contamination of the normal radioisotope composition of the earth with addition artificially produced radioactive atoms.
Carbon dating cannot be used on most fossils, not only because they are almost always allegedly too old, but also because they rarely contain the original carbon of the organism that has been fossilized.
Also, many fossils are contaminated with carbon from the environment during collection or preservation procedures.
Carbon-14 cannot be used to date biological artifacts of organisms that did not get their carbon dioxide from the air.
This rules out carbon dating for most aquatic organisms, because they often obtain at least some of their carbon from dissolved carbonate rock.
the geological column and approximate ages of all the fossil-bearing strata were all worked out long before anyone ever heard or thought about radioactive dating …
There are so many sources of possible error or misinterpretation in radiometric dating that most such dates are discarded and never used at all, notably whenever they disagree with the previously agreed-on [index fossil] dates.” (Dr Henry Morris, creationist scientist and hydraulicist, Ph D in hydrology, geology and mathematics, Fellow of the American Association for the Advancement of Science and the American Society of Civil Engineers, former Professor of Hydraulic Engineering at Virginia Polytechnic Institute, 1974) Michael Oard, Ph. is a meteorologist and creationist scientist who writes, And when it comes to dating any individual rock today, the resulting “date” is forced to conform to predetermined evolutionist “dates” based on these imaginary 19th century index-fossil “dates”.
That’s right, you guessed it, the paleontologist tells the geologist how old the rock is based upon its connection to those very same “index fossils.” The process of using index fossils is describes by the late Creationist author and Ph. The supposed age of “index fossils” is based on how long these 19th century evolutionists believed one kind of animal would take (somehow) to “evolve” into a different kind of animal.