Carbon dating validity
As we pointed out in these two articles, radiometric dates are based on known rates of radioactivity, a phenomenon that is rooted in fundamental laws of physics and follows simple mathematical formulas.
Dating schemes based on rates of radioactivity have been refined and scrutinized for several decades.
Whenever possible we design an age study to take advantage of other ways of checking the reliability of the age measurements.
The simplest means is to repeat the analytical measurements in order to check for laboratory errors.
In a related article on geologic ages (Ages), we presented a chart with the various geologic eras and their ages.
In a separate article (Radiometric dating), we sketched in some technical detail how these dates are calculated using radiometric dating techniques.
Another method is to make age measurements on several samples from the same rock unit.
Along this line, Roger Wiens, a scientist at the Los Alamos National Laboratory, asks those who are skeptical of radiometric dating to consider the following (quoted in several cases from [Wiens2002]): All of the different dating methods agree--they agree a great majority of the time over millions of years of time.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.Other objections raised by creationists are addressed in [Dalrymple2006a].The overall reliability of radiometric dating was addressed in some detail in a recent book by Brent Dalrymple, a premier expert in the field. 80-81]: These methods provide valid age data in most instances, although there is a small percentage of instances in which even these generally reliable methods yield incorrect results.
The isochron techniques are partly based on this principle.