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.
So, we have a “clock” which starts ticking the moment something dies.
Since the flood was accompanied by much volcanism (see Noah's Flood…, How did animals get from the Ark to isolated places? ), fossils formed in the early post-flood period would give radiocarbon ages older than they really are.
In summary, the carbon-14 method, when corrected for the effects of the flood, can give useful results, but needs to be applied carefully.
These techniques, unlike carbon dating, mostly use the relative concentrations of parent and daughter products in radioactive decay chains.
For example, potassium-40 decays to argon-40; uranium-238 decays to lead-206 via other elements like radium; uranium-235 decays to lead-207; rubidium-87 decays to strontium-87; etc.
Familiar to us as the black substance in charred wood, as diamonds, and the graphite in “lead” pencils, carbon comes in several forms, or isotopes.
One rare form has atoms that are 14 times as heavy as hydrogen atoms: carbon-14, or C ratio gets smaller.Clearly, such huge time periods cannot be fitted into the Bible without compromising what the Bible says about the goodness of God and the origin of sin, death and suffering—the reason Jesus came into the world (See Six Days? He said, This only makes sense with a time-line beginning with the creation week thousands of years ago.It makes no sense at all if man appeared at the end of billions of years.It does not give dates of millions of years and when corrected properly fits well with the biblical flood.There are various other radiometric dating methods used today to give ages of millions or billions of years for rocks.We will deal with carbon dating first and then with the other dating methods.