Carbon dating flaws wiki
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.
Overall, the energy of the Earth's magnetic field has been decreasing, so more C is being produced now than in the past.
Anything over about 50,000 years old, should theoretically have no detectable C.
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.
So, we have a “clock” which starts ticking the moment something dies.
Obviously, this works only for things which were once living.