Do radiometric dating problems
Radioactive decay rates have been measured for over sixty years now for many of the decay clocks without any observed changes.
And it has been close to a hundred years since the uranium-238 decay rate was first determined.
A recent survey of the rubidium-strontium method found only about 30 cases, out of tens of thousands of published results, where a date determined using the proper procedures was subsequently found to be in error.
One question that sometimes arises here is how can scientists assume that rates of radioactivity have been constant over the great time spans involved.
The differences actually found in the scientific literature are usually close to the margin of error, usually a few percent, not orders of magnitude!
We scientists who measure isotope ages do not rely entirely on the error estimates and the self-checking features of age diagnostic diagrams to evaluate the accuracy of radiometric ages.Also, as the authors of the 1968 article were careful to explain, xenoliths cannot be dated by the K-Ar method because of excess argon in bubbles trapped inside [Dalrymple2006].Thus in this case, as in many others that have been raised by skeptics of old-earth geology, the "anomaly" is more imaginary than real.The slope of the line determines the date, and the closeness of fit is a measure of the statistical reliability of the resulting date.Technical details on how these dates are calculated are given in Radiometric dating. As with any experimental procedure in any field of science, these measurements are subject to certain "glitches" and "anomalies," as noted in the literature.
The isochron techniques are partly based on this principle.