Carbon dating problem
The ratio of Sr-87 to Sr-86 is graphed versus the ratio of Rb-87 to Sr-86 for several different parts of the rock. Sr-86 is another stable form of strontium, but it isn’t produced by radioactive decay.
Thus, it provides an independent analysis of the rock that does not depend on the radioactive decay that is being studied.
If some process brought Sr-87 into the rock, it probably brought different amounts of the atom into different parts of the rock, so the ratio of Sr-87 to Sr-86 won’t stay consistent from one part of the rock to another. He says that there is one process that has been overlooked in all these isochron analyses: diffusion.
If a consistent isochron is generated, however, we can be “certain” that no process interfered with the relative amounts of Rb-87 and Sr-87, so the radioactive date is a good one. Atoms and molecules naturally move around, and they do so in such as way as to even out their concentrations.
Most likely, the effect will be dependent on the age.
I would think that the older the sample, the larger the overestimate.
Generally, we are told that scientists have ways to analyze the object they are dating so as to eliminate the uncertainties due to unknown processes that occurred in the past. Hayes has pointed out a problem with isochrons that has, until now, not been considered.As someone who has studied radioactivity in detail, I have always been a bit amused by the assertion that radioactive dating is a precise way to determine the age of an object.This false notion is often promoted when radioactive dates are listed with utterly unrealistic error bars.That’s just over half a percent error in something that is supposedly multiple billions of years old.Of course, that error estimate is complete nonsense.
One way this is done in many radioactive dating techniques is to use an isochron. To understand the problem, let’s start with an example of how radioactive dating works. Sr-87 is not radioactive, so the change is permanent.