Speed dating rotation
The data do not fall on any straight line and do not, therefore, form an isochron.The original data are from a report by Wasserburg and others , who plotted the data as shown but did not draw a 34-billion-year isochron on the diagram.The interpretation that the data represent a 34-billion-year isochron is solely Woodmorappe's  and is patently wrong.(Dalrymple, 1984, pp.78-79) Whatever the reasons may be for the scatter, the fact remains that these data were clearly a "discard" case.Today, we have some 100,000 radiometric dates, the vast majority contributing sensibly to the overall picture.Woodmorappe's main theme, minus the diplomatic wording, is that geologists are cheating like so many schoolboys to make their dates come out right.An eye-opener awaits anyone who closely examines Woodmorappe's list of bad dates. The results make the method stronger, either by advising us to avoid certain minerals under certain conditions or by building our confidence in applying it to new materials or situations. That is, they were rejected because of internal indicators (such as a bad isochron) rather than on the basis of the final date produced. All of the dates lack the investigator's personal, detailed interpretation. Again, one must demonstrate that a bad date would have been counted as a good date had it not been contradicted by outside data.
The Pharump diabase from the Precambrian of California yielded an Rb-Sr isochron of no less than 34 b.y., which is not only 7 times the age of the earth but also greater than some uniformitarian estimates of the age of the universe.
But even schoolboys need to know what the right answers are in order to cheat, and there was no absolute age list when radiometric dating was first applied to the strata.
Anyone can make up a list of bad cars, bad people, bad neighborhoods, or bad radiometric dates. Is it unsafe for you to drive a car, to meet new people, or to live in a neighborhood? The thing that is lacking in Woodmorappe's argument is statistical balance.
(Matson, 1993, p.1) Either we have a worldwide conspiracy among geologists, which no sane person believes, or else the numerous radiometric dates were consistent enough to allow that kind of close agreement. Dalrymple, an expert in radiometric dating with lots of hands-on experience, puts the percentage of bad dates at only 5-10 percent.
Thus, we clear away the first illusion spun by creationism, namely that most of the dates are bad, that the radiometric picture is totally chaotic.