Radiometric Dating and the Geologic Column: A Critique

Sorry, your post does not support " ... the YEC assertion that radiometric dating is flawed, because it verifies YECs first and second predictions that radiometric dating will frequently yield ages which are grossly discordant compared with the predictions of geochronology and that such discordances will frequently exhibit poor precision."You have extrapolated the analysis of a flawed and biased sample to the statistics of a much larger population. Alas, that's invalid.To support your thesis, you need to discuss exactly how the 432 sample dating studies were chosen (the brief answer is that Woodmorappe specifically chose samples that were known to exhibit problems), the relationship of the statistics samples chosen to the population of all possible samples (the brief answer is that the samples chosen are hopelessly biased and therefore the analysis of them bears no relationship to the statistics of the population), and you should discuss whether or not Woodmorappe accurately transmits and represents the content of the chosen studies (the brief answer is that in many cases he does not).You also need to discuss the many "age-diagnostic" radioisotope dating methods such as Ar-Ar, the several varieties of isochron methods (especially including Pb-Pb), and the concordia-discordia methods. These avoid several of the issues which can (but seldom do, as verified by cross-checking) affect K-Ar dating. Since a large majority of the dating studies performed in the last 20 years or so (that is, several thousands to tens of thousands) are not K-Ar studies but are the more robust age-diagnostic methods, ignoring them relegates your "study" to yet another YEC sidestepping of the real data.

Sorry, that's just flat-out wrong. Your claim is "radiometric dating will frequently yield ages which are grossly discordant compared with the predictions of geochronology and that such discordances will frequently exhibit poor precision." {emphasis added}. No mere compilation of ages can prove those claims. "Frequently" requires comparison to some other appropriate and justified number. Is 432 of something frequent? You can't tell until you compare it to something else. 432 major snowstorms per year is frequent; 432 snowflakes falling per year is not frequent.Of course, given Woodmorappe's well-known and documented mendacity and misrepresentations, the number of truly problematic studies in his sample is certainly less than 432. But I don't know what the right number is so, for the sake of argument only, let's take 432 as the number.Then all you have proven so far is that there are some problematic studies. Neither you nor Woodmoorappe have even tried to do the necessary statistics ... partly because the sampling is hopelessly flawed (it's not representative of the population) and, I suspect, partly because both of you know what the result would be and you don't want to acknowledge that result.OK, some studies are problematic. Until you can relate that to the properties of the population of all studies, using rigorous and well-understood statistical methods, you haven't even indicated an overall problem, much less a young Earth.

There's also another significant source of such dates; tests of possibly inappropriate materials to verify whether or not they are inappropiate, especially those studies which conlude that the material is inappropriate. Such tests are the source of the old "fresh clams dated by radiocarbon tested as old" canard (the study was verifiying that marine organisms couldn't be tested meaningfully), the old "Volcanic rocks produced by lava flows which occurred in Hawaii in the years 1800-1801 were dated by the potassium-argon method. Excess argon produced apparent ages ranging from 160 million to 2.96 billion years." lie (the study was lookin specifically at dating xenoliths in the lava).

I happen to have a scanned copy of Dalrymple (1984) with me (I'm asking permission to distribute the entire thing. Here's the figure to which the Dalrymple text refers: It's pretty obvious that only a moron would try to draw one straight line through those data points!Let's also post the text from Dalrymple about Woodmorappe¹ just before the part you posted:

Expected age (million years)	Age obtained (million years)	Formation/locality
52	39	Winona Sand/gulf coast
60	38	Not given/gulf coast
140	163,186	Coast Range batholith/Alaska
185	186-1230	Diabase dikes/Liberia
-	34,000*	Pahrump Group diabase/California
*This example was not tabulated by Woodmorappe (134) but was discussed in his text.

Table 2: Examples of Supposedly Discrepant Radiometric Ages, as Tabulated and Discussed by Woodmorappe (134)

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Removed extra line breaks from table. --Admin

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The two ages from gulf coast localities (Table 2) are from a report by Evernden and others (43). These are K-Ar data obtained on glauconite, a potas-sium-bearing clay mineral that forms in some marine sediment. Wood-morappe (134) fails to mention, however, that these data were obtained as part of a controlled experiment to test, on samples of known age, the applica-bility of the K-Ar method to glauconite and to illite, another clay mineral. He also neglects to mention that most of the 89 K-Ar ages reported in their study agree very well with the expected ages. Evernden and others (43) found that these clay minerals are extremely susceptible to argon loss when heated even slightly, such as occurs when sedimentary rocks are deeply buried. As a re-sult, glauconite is used for dating only with extreme caution. Woodmorappes gulf coast examples are, in fact, examples from a carefully designed experi-ment to test the validity of a new technique on an untried material.

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The ages from the Coast Range batholith in Alaska (Table 2) are referenced by Woodmorappe (134) to a report by Lanphere and others (80). Whereas Lanphere and his colleagues referred to these two K-Ar ages of 163 and 186 million years, the ages are actually from another report and were obtained from samples collected at two localities in Canada, not Alaska. There is nothing wrong with these ages; they are consistent with the known geologic relations and represent the crystallization ages of the Canadian samples. Where Woodmorappe obtained his 140-million-year expected age is anyones guess because it does not appear in the report he cites.

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The Liberian example (Table 2) is from a report by Dalrymple and others (34). These authors studied dikes of basalt that intruded Precambrian crystal-line basement rocks and Mesozoic sedimentary rocks in western Liberia. The dikes cutting the Precambrian basement gave K-Ar ages ranging from 186 to 1213 million years (Woodmorappe erroneously lists this higher age as 1230 million years), whereas those cutting the Mesozoic sedimentary rocks gave K-Ar ages of from 173 to 192 million years. 40Ar/39Ar experiments4 on samples of the dikes showed that the dikes cutting the Precambrian basement contained excess 40Ar and that the calculated ages of the dikes do not represent crystal-lization ages. The 40Ar/39Ar experiments on the dikes that intrude the Meso-zoic sedimentary rocks, however, showed that the ages on these dikes were reliable. Woodmorappe (134) does not mention that the experiments in this study were designed such that the anomalous results were evident, the cause of the anomalous results was discovered, and the crystallization ages of the Liberian dikes were unambiguously determined. The Liberian study is, in fact, an excellent example of how geochronologists design experiments so that the results can be checked and verified.

¹Woodmorappe, J. 1979. Radiometric geochronology reappraised. Creation Res. Soc. Quart. 16: 102-129, 147.{Upated image link)This message has been edited by Admin, 12-09-2004 06:53 PMThis message has been edited by JonF, 03-07-2005 11:24 AMEdited by JonF, : Update image URL

Just for grins, a table of many such estimates extracted from Dalrymple's 1991 book is at Pre-1900 Non-Religious Estimates of the Age of the Earth.pdf.

Only because you made up your mind before examining the evidence, and you (and Woodmorappe) have done an exceptionally poor job of examining the evidence.Until and unless you compare your sample to the the population using standard and established statistical methods, all you have established is that some problematic dates exist.PurpleYouko pointed out how easy it is to collect appropriate data in Message 19. Of course, collecting and analyzing realistic data wouldn't give you the result you want ...

Maybe he does. His use of a pseudonym has no relationship to the validity or in-validity of his arguments.

But I am pretty sure that nobody, including Woody, has put any such paper (full of cherry-picked discordant dates) on the Internet. Even if somebody did, of necessity much of the detail would be contained in papers not available to non-academics on the Internet.From the last paragraph of STUDIES IN CREATIONISM AND FLOOD GEOLOGY it appears that the contents of "Studies in Flood Geology" (Anti-Climacus' reference)relating to radioisotope dating are nothing more than a reprint of "Radiometric Geochronology Reappraised" (Creation Research Society Quarterly, 16(2)102-29, 147; September 1979) which has been so extensively criticised and debunked in so many venues, including this thread.

For isochrons, it's usually by sophisticated statistical analysis of how well the data fit a straight line. (Since the data does not fit the requirements for the common least-squares analysis to be applicable, much more sophistication is required).In this particular case no sophisticated analysis was required to see that there was no isochron line. Here's the picture again: There is an independent method; statistical analysis of the fit to a straight line. There's some discussion of this on apge 21 of http://www.bgc.org/Isoplot3betaManual.pdf.Are you seriously proposing that the refusal to draw one straight line through the data points in the figure above is an "ad hoc rationalization"? Or do you agree that those points do not lie on a straight line?

And ... Woody also plotted that data in the same way (or at least a similar set of data) on the top of a left-hand page around the middle of "The Mythology of Modern Dating Methods" (my copy of which is a few thousand miles away right now).He then drew in a blob in the empty area at the lower right and a blob near the "400" on the Y axis and a blob in the empty area at the the top middle of the graph. In these blobs he wrote short derogatory statements about geologists not daring to publish the results that fell inside those blobs. No evidence that any such results existed, no discussion of why he believed such results existed ... just the claims.Ol' Woody. A real piece of work.(edited to add: Yippee! Just went over 1K posts in this thread!)This message has been edited by JonF, 12-09-2004 09:52 PM

New Educational Activities for Home Schooling Science: A Hands-on Science Activity that Demonstrates the Atheism and Nihilism of Evolution is the most commonly cited example of such activity.Woodmorappe has in the past threatened to sue people who identified him as Peczkis. Unfortunately for him, Tom McIver outed him in an obscure footnote in a book circa 1988 (probably in Anti-Evolution: An Annotated Bibliography, although I'm not sure) and apparently this made it "public domain" and removed his standing to sue others. I've seen claims that Tom did that and did it obscurely on purpose, for just that reason.

So the study you quote is strong evidence against your claim that discordant results are suppressed.I see no reason why you characterizse the explanations as "rationalizations" and "dubious" other than the fact that you don't like their primary conclusions.There is no miraculous exemption of concordant data ... there are clear differences between the prcesses to which the mineral separates and the leachates have been exposed. That's the simplest and most likley explanation for the differences.All in all, a nicely done paper in which the authors didn't claim too much, presented the data warts and all, and proposed explanations (and their reasons for those explanations) but didn't dogmatically i;nsist that they had the only possible explanations.OTOH, there's no reason to believe that the problems encountered in this study are typical. So, here we are after 65 messages on five pages, and you have yet to adress the fundamental and fatal flaw in cour data and thesis: there's no valid way of extrapolating from your data (including this example) and the characteristics of the set of all dating studies because the data (and your most recent example) were specifically chosen so as to be notrepresentative of teh set of all dating studies.I hope you adress that flaw over the weekend. I doubt you will.

Yup. Dalrymple discusses this extensively in "The Age of the Earth", Stanford University Press, 1991. Since you appear to be in an academic setting there's a pretty good chance you can find it in your library, and it's the classic fairly technical introduction to radioisotope dating methods and the sources of the evidence for Earth's age (he doesn't talk much about studies of things younger than the Earth). You want to know more about dating, start with Dalrymple. You want to know more about analytical techniques and serious technical discussion, read "Principles of Isotope Geology, 2nd Edition", Gunter Faure, Wiley 1986 and "Radiogenic Isotope Geology", Alan P. Dickin, Cambridge University Press, I don't know the date 'cause I'm on the road. The second edition of Dickin is available, now with figures, at Radiogenic Isotope Geology, but this may disappear at any moment (publication is scheduled for March 2005).Some relevant tables from Dalrymple are at the end of Lordibelieve. More evidence at Lordibelieve.

I agree, but IMHO a nearly-as-important secondary point/claim is the frequency of discordant dates, which he has made no effort to support other than by asssertion.Of course, if one were to accept his claim of frequent errors, that would immediately lead to the conclusion that some of the radiosotope age determinations are correct!It all boils down to the ol' chestnut: we don't know everything therefore we know nothing.

Nope, just an enthusiastic amateur. I have a BSME & MSME from MIT. I spent about 25 years designing and supervising design of capital equipment used in the semiconductor industry. Got out when the industry collapsed about three years ago; it's just not as much fun as it used to be now that the industry is more mature (some might say stodgy). Now I consult on design and AutoCAD (I'm probably one of the world's greatest experts on connecting AutoCAD and databases ... talk about a minuscule puddle in which to be a big frog!), do course development and some teaching for my wife's training & organizational development consulting business, and do PC repair in the local area just to get out of the house and meet people and pick up a little extra money.