Accuracy of radiocarbon dating
These techniques are applied to igneous rocks, and are normally seen as giving the time since solidification.
The isotope concentrations can be measured very accurately, but isotope concentrations are not dates.
To derive ages from such measurements, unprovable assumptions have to be made such as: There is plenty of evidence that the radioisotope dating systems are not the infallible techniques many think, and that they are not measuring millions of years. For example, deeper rocks often tend to give older “ages.” Creationists agree that the deeper rocks are generally older, but not by millions of years.
Geologist John Woodmorappe, in his devastating critique of radioactive dating, points out that there are other large-scale trends in the rocks that have nothing to do with radioactive decay.
We will deal with carbon dating first and then with the other dating methods.
Carbon has unique properties that are essential for life on Earth.
Accordingly, carbon dating carefully applied to items from historical times can be useful.Overall, the energy of the Earth's magnetic field has been decreasing, so more C is being produced now than in the past.