A very common claim of young earth creationists in trying to reject the evidence for an old earth is to loudly proclaim that radiometric dating methods “makes assumptions” and that these “assumptions” are somehow fatally flawed or not supported by evidence.
These claims generally land in three different categories: (1) radiometric dating assumes that initial conditions (concentrations of mother and daughter nuclei) are known, (2) radiometric dating assumes that rocks are closed systems and (3) radiometric dating assumes that decay rates are constant.
The initial conditions are just read off the graph; it is not just assumed.
In a last ditch effort, young earth creationists exclaim that scientists just assume, without warrant, that decay rate are constant. Decay rates have been shown to be constant, despite very high pressure and temperature.
But what happens when the rocks have been disturbed?
If a rock is heated during its lifetime, the system gets disturbed and some of the parent and/or daughter isotopes may move in or out of the rock.
Surely, if some daughter nuclei left the rock or parent nuclei entered the rock, the dates would come out all wrong! Follow Debunking Denialism on Facebook or Twitter for new updates.
While this is technically true, there are several mini-industries dedicated developing methods and techniques to make sure that there is no contamination and check to see if the rocks where disturbed between forming and being tested by scientists. On of the great things about many forms of radiometric dating is that they are self-checking.
Measuring this ratio gives us an idea of how long ago the rock formed. Doesn’t this assume that the rocks are closed systems?
Let us critically examine each of these claims and see if they hold up against the science.
While doing so, we will have to learn about how radiometric dating works.
Those that did the decaying are called parent nuclei.
If you have a rock that contains radioactive isotopes, these will decay over time.
Most young earth creationists reject all of these points.