Radiometric Dating

Discussion in 'Creation vs. Evolution' started by Administrator2, Jan 23, 2002.

  1. Administrator2

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    Jun 30, 2000
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    Joe asked for something other than 'anecdotal' accusations regarding problems with anomalies in radiometric dating. So, deciding to take a little time with this, I did a little web-crawling tonight so that everyone can check my sources. Here is what I found. As I state below, I am NOT trying to debunk the consistent old ages found in radiometric dating. What I am doing is precisely what I was asked to do -- reference my claim that radiometric dating is nevertheless beset with problems which end up in a lot of dates being thrown out for the ones that 'fit' the preconceived ages of the materials being tested. With that said, here:


    "Radiocarbon Dating: Fictitious results with Mollusk Shells", M. Keith and G. Anderson, Science, Vol 141, 8-16-63, pp. 634-636.

    "Radiocarbon Activity of Shells from Living Clams and Snails", M. Rubin and D. Taylor, Science, Vol 141, 8-16-63, p. 637.

    From here:
    An understanding of time is of great importance to the geologist. Geologists obtain estimates for the passage of time from two distinctly different sources. So-called 'absolute' radiometric dates are derived from the decay rates of various radioactive isotopes in igneous (volcanic or molten) rocks. Although the underlying theoretical basis for 'absolute' or radiometric dating appears to be sound, there are some troubling issues arising from its application that are yet to be resolved. For example, a recent careful study based on zircon crystals in basalts (lavas) from cores taken nearest the Mid-Atlantic Ridge yielded uranium-lead dates ranging from 330 million to 1.6 billion years in rocks expected to give dates of at most a few thousand years. The authors had no coherent explanation for the anomalous dates. Furthermore, the uranium decay series itself exhibits some curious properties.
    In the series, a number of isotope pairs can be used for dating. However, the different pairs nearly always give different dates for the same rocks, and these differences themselves appear to be systematic. Numerous other anomalies exist, but these are still exceptions to the overall apparently coherent pattern of radiometric dates in the geologic record.

    From here:
    Potential Anomalous Results
    Experimentation has determined that the rate of production of radiocarbon in the earth's atmosphere is not constant. This is due to variations in the heliomagnetic modulation of the galactic cosmic radiation. Differences of several percent have been observed in the radiocarbon concentrations of contemporary plants. Dating errors, independent of statistics or laboratory procedures, caused by these variations in the sun's magnetic field, can be as much as several hundred of years. It is generally considered that four radiocarbon dates on a specific feature is sufficient to identify the occurrence of this error.

    You are probably familiar with this forum --
    Where Karen gave a pretty good example here:
    Early attempts to date the KBS tuff (1969) gave an age of 212-230 million years which was immediately rejected as an extraneous argon age discrepancy, because of the presence of Australopithicine and other mammalian fossils beneath the tuff (Fitch & Miller 1970, Nature 226:226-8).
    The dating was complicated because the tuff is a water-transported mixture. But they did find an acceptable date, which was then confirmed by several "independent methods":

    In the early 1970's the KBS tuff was "securely dated" at 2.6 million years based on:
    - Vertebrate faunas -- Elephant, Suid (pig), Australopithicus, and tools
    (Maglio, 1972; Nature 239:379-85, Leaky, 1967-69, etc.)
    - Potassium-Argon dating -- selected crystals (K-Ar and Ar40-Ar39)
    (Fitch & Miller '70, Nature 226:226-8 and see 251:214)
    - Paleomagnetism -- polarity data, based on 247 samples below KBS tuff
    (Brock & Isaac, 1974, Nature 247:344-48)
    - Fission Track Dating -- involving uranium, noting possible reanealing
    (Hurford, 1974, Nature 249:236; '76, 263:738)

    In the mid 1970's Leaky's team found Skull 1470 below the KBS Tuff (Leaky,'73, Nature 242:447, National Geographic June, 1973 pp 819-829) and Leaky said, "either we toss out this skull, or we toss out our theories of early man". Skull 1470 was "too modern" to be found at that level, if the Australopithicenes (found both above and below the KBS tuff) were ancestral to modern man.

    Other anthropologists, notably Johanson's team at Berkeley, couldn't accept any claim of such modern hominids in strata dated almost 3 million years old. They tried to redate the KBS. It was a complex problem because the tuff is a slurry of volcanic debris. But they did find and publish a date that was suitable to them: 1.8 million years, based on:

    - Hominid Fossils -- Skull 1470 and other similar skulls below KBS tuff

    - Potassium-Argon (K-Ar) -- on pumice from the KBS tuff and Ar-Ar -- on selected feldspar crystals (Ar40-Ar39) (Curtis et al,1975, Nature 258:395 (& see 284:229,230 & 294:123)

    Then in the late 1970's, a remarkable thing happened. One by one (with much heated controversy apparent in the papers) the other "independent methods" re-evaluated their work in light of the new radiometric date, and confirmed the new age:

    - Paleomagnetism -- pinpointing a different polarity reversal, in light of the change in the K-Ar date (Hillhouse et al, 1977, Nature 265:411)

    - Vertebrate Faunas -- three suid (pig) species (based on teeth) suggesting possible phylogenetic branching and its timing in relationship to the new radiometric date
    (Cooke, 1978; Science 201:460-63 (&198:13-21)

    - Fission Track Dating -- (U-238 in zircon) emphasizing re-anealing, in light of the change in the accpeted K-Ar date (Gleadow, 1980, Nature 284:229-230)

    By 1980 there was a new "remarkably concordant" well-accepted radiometric date.

    Do you see what happened? Many more dates than those mentioned here were obtained by radiometric methods, but the choice of which one to accept was made on the basis of the fossils (as you pointed out), because the acceptable range of dates for each fossil form was known (by evolutionary theory).

    At each change, the authors may well have sincerely felt that they were separating truth from error. How did they know whether a newly calculated date was right or wrong? What was the basis by which they could judge the acceptability of the date, at 1.8 or 2.6 or 200 million? Was it the fossil record, or accepted ideas about the correct ages of the fossils?

    If the deposit had Australopithecines, it could not be 200 million years old, but 2.6 million was alright. If it had more modern hominid skulls, and these evolved from the Australopithicenes, it had to be younger than 2.6 million years old. So the it was the fossils that gave the constraints for the dates -- or, rather, the accepted evolutionary age of the fossils was the criterion that gave the constraints for the acceptable geologic age of the strata. When the known fossil data changed (with their attendant acceptable ages), the chosen date also changed.

    Evolutionary theory _about_ the fossils was what gave credence to the published dates that were selected from the range of dates obtained by radiometric and other dating methods.

    Is this an isolated case? Not at all. In studies where a range of dates is obtained, the ones in the right ball park are presented, giving the limits of the correct age, and the anomalous ones (if mentioned at all) are explained in terms of mixing of sediments, extra Argon retention, leaching, and other very plausible processes. The explanations for anomalously old or anomalously young ages may be quite accurate (and may apply to the accepted ages as well!). If no acceptable age is found, the results may not be published at all.

    My point is that the accepted ("non-anomalous") age is the age within the timeframe set by evolutionary theory. So it is evolutionary theory that dictates which radiometric results will be acceptable to publish as the age for a fossil. If you want to accept this, you may. But there may be a more sure timescale. I hope we all look very seriously at this and make wise choices.

    Or consider this:
    Has it been dealt with by evolutionists yet?

    Just how old are those modern-looking human skeletons in those chunks of Guadeloupe limestone? (Opposing views were discussed in SFs #27 and 34.) The basic problem is the dating of the limestone in which the skeletons are embedded. If the limestone is truly of Miocene age (about 25 million years old), the presence of human skeletons represemts a major scientific anomaly, since modern man appeared on earth only about 5 million years ago. Most scientists say the limestone is only recently formed beach rock a few hundred years old, and that radiometric dating proves this. But doubters have pointed to 3-millionyear-old coral reefs apparently stratigraphically above the limestone. In a recent issue of Ex Nihilo, a few more cans of gasoline have been thrown on the fire:

    (1) The radiometric date usually served up actually came from another island in the area.
    (2) Beach rock is not now forming at the site, rather the skeletons' limestone is being eroded.
    (3) The skeletons' limestone is harder than marble and not loosely consolidated beach rock.
    (4) True Miocene limestone does exist in the area.
    (5) Geologists have carefully described and mapped the rest of Guadeloupe but have omitted the skeletons' site -- presumably because of the anomalies involved.
    (Tyler, David J., et al; Ex Nihilo, 7:41, no. 3, 1985.)

    And I know you don't like John Woodmorappe, but his book on radiometric dating has basic data in it that is really damaging. Here is a report from here:

    Woodmorappe has assembled an impressive and disconcerting collection of anomalous radiometric dates. Over 300 serious discrepancies are tabulated and backed by some 445 references from the scientific literature. To remove triviali-ties, only dates that were "wrong" by 20% or more were included. This criterion insured that the anomalous dates were off by one or more geological periods. To enhance his case, Woodmorappe excluded data for such troublesome minerals as K-feldspar, which have unreliable records. The surviving discordances will certainly disturb anyone who has long accepted radioactive dating as the near-final word in geochronology.

    The lengthy text accompanying the table delves into the geological problems posed by the tabulated anomalies, primarily the severe distortions implied in the supposedly well-established geological time scale. Many attempts have been made to explain away these discrepancies, usually by asserting that the system must have been "open"; that is, contamination and/or removal of materials occurred. But a far more serious situation exists: the reluctance of researchers to publish radiometric dates that fly in the face of expectations. Data selection and rejection are epidemic. Some authors admit tossing out wild points; others say nothing.

    (Woodmorappe, John; "Radiometric Geochronology Reappraised," Creation Research Society Quarterly, 16:102, 1979.)

    My point, Joe, is actually not to fully discredit the old ages given by radiometric dating, but to simply point out, as you asked for with references this time, that there are significant problems where anomalies in this type of dating are concerned. Dates ARE thrown out when they don't agree with a preconceived model. Trying to deal with discordances and anomalies are standard parts of courses in this type of dating.

    I am currently editing and proofing a new paper on a critique of some specific radiometric dating and if it were not unethical, I would just about give my right arm at this moment to quote parts of it to you. What is documented, however, is that Holmes tossed a rather large number of radiometric dates in order to fit with Lyell's ideas. A meeting held later by professionals in the field (in the 1970's) resulted in some serious doubts regarding the possibility of harmonization between radiometric dating and what geology actually shows. I can't go further than that, but yes, there are problems and yes, a lot of dates get trashed.

    What is funny is that I think Barry's work shows why some of these anomalous dates are showing up where they do. I don't have it with me, Joe, as Barry left for Australia yesterday, but there is a book which shows the standard results of hundreds of radiometric date results as a sort of a hill-shaped curve. EXCEPT that there are about twelve peaks where dates seem to clump more than others.

    Out of curiosity, Barry checked those peaks last spring and found something that didn't just surprise him, it just about knocked his socks off - those twelve peaks correlate almost exactly with twelve areas of redshift clumping seen in the galaxies. And that would certainly be a possible validation for what Barry is presenting regarding the slowing speed of light - for if, as he presents, both the redshift and speed of light (and therefore radiometric dates) are dependent on the same cause (the ZPE increase, as indicated by the increase in the measurements of Planck's constant and the electron rest mass), then we should expect to see such harmonization. Nevertheless, the fit was something of a shock.

    Go check the data for yourself.

    You said earlier these ages were tossed out before being published. Now you cite published works. Which argument do you prefer? Are the dates being supressed from the literature or are they being published? Please note, I acknowledge there are times when radioactive methods don't work. You seem to think they predominate, they do not predominate in the published literature. I never said you could not find evidence for some anomalies in published ages, I want you to support your claim that the anomalous ages are tossed out before publication.
    So far, you provide nothing to support this claim! Now show me the evidence for tossed out bad ages.
    As for Holmes, you forget to point out that Arthur was developing mass spectrometry for dating and that many daughter products in the decay chain were not known. It is not surprising that Holmes' work had problems. The early half of the 20th century was a time for working out the major bugs in radiometric dating instrumentation and figuring out just exactly what happens during radioactive decay and what daughter products were produced.
    What you also failed to mention about Holmes' work is that NONE OF IT, not a single age determination (NOT ONE) suggested an age anywhere close to 6000 years. For that, you have to rely on an unpublished reference to support your claim (Barry's work). Now I can certainly understand your defense of your husband's work, but deep down you understand that until it is published and dissected by the larger physics community, his work is irrelevant to the topic. Let's get it published and then we can talk about the issues with radiometric dating.

    Having a bunch of radiometric dating tests done and then throwing out most of the results prior to publication can get pretty darned expensive.

    A look at the price-list over at shows that a vanilla K-AR test costs *at least* $400 (if the customer does all the sample preparation).

    An Rb-SR age determination costs about $500 per sample.

    A basic C-14 test (no mass-spectroscopy) will set you back $300.

    Helen, I'm sorry, but your post only shows how little you understand of the process of radiometric dating. What do you expect? Do you want radiometric dating to be simple? Do you expect it to be like measuring the air temperature? Do you expect amateurs to be able to do it in their garages with a hot plate and beaker? Why do you think people spend careers studying this stuff?

    The point is that this is a highly technical field that has numerous possible sources of error. Geochronologists are trained to evaluate these errors and make judgements as to the validity a given method and of the resulting data.

    I'm not sure where you got the idea that anomalies, in themselves are inherently harmful to the evolutionary models. We have no reason to cull them or stifle their publication (except from competitors).
    Believe it or not, they fit in very neatly with our concept of geology and stratigraphy.

    These excerpts from one of your quotes are of particular interest. They show that, even with the potential sources of error, the authors still support the use of radiometric dating methods, at least when properly applied and executed.
    "Although the underlying theoretical basis for 'absolute' or radiometric dating appears to be sound, there are some troubling issues arising from its application that are yet to be resolved.
    Numerous other anomalies exist, but these are still exceptions to the overall apparently coherent pattern of radiometric dates in the geologic record.

    Here is the old KBS tuff argument, that I assume you are trying to resurrect.

    …The dating was complicated because the tuff is a water-transported mixture. But they did find an acceptable date, which was then confirmed by several "independent methods"

    Interesting. So they had reason to question the original results and further testing led to results that made sense vis a vis the fossil evidence. I don't suppose you want to talk about why the original date was tainted. Now, I am I to understand the you do not check your own data by independent methods? Do you ever find errors? Are there reasons for those errors, like a miscalculation or misapplication of an equation? Do you publish those errors? Do you realize that the only way you know about this "problem" is because it was published somewhere? Isn't it the creationist argument that discordant dates are not published?

    I'm not crusading against [radiometric dating]. I think I have said that MANY times. I was simply verifying the fact that there are a lot of problems involved. Joe and others challenged me when I said that, so I posted the above material.

    There are problems. They do not invalidate radiometric dating per se, but they do require a lot more understanding than we now have.

    That is my point. It is admitted. It is taught. What is the problem?

    Then if the problems don't invalidate the method (which they don't), why even bring it up?

    …the fact that there are a lot of problems involved. Joe and others challenged me when I said that, so I posted the above material
    That is my point. It is admitted. It is taught. What is the problem?

    Not quite true. I challenged you to supply evidence that radiometric dates are (with some high frequency) tossed out prior to publication. You're trying to bait and switch here to avoid the original claim.

    I'm not crusading against it. I think I have said that MANY times. I was simply verifying the fact that there are a lot of problems involved. Joe and others challenged me when I said that, so I posted the above material.

    Can we say that you support the concept of radiometric dating? And yes there are a lot of problems involved. I also have a lot of problems putting in my garden each year, but somehow I manage. It is silly to suggest that since there are problems doing something that it is somehow invalid or not worthwhile.

    There are problems. They do not invalidate radiometric dating per se, but they do require a lot more understanding than we now have.

    You mean they require a lot more understanding that YOU have.

    That is my point. It is admitted. It is taught. What is the problem?

    The issue is that you omit the fact that problems with radiometric dating are largely manageable if they are understood and recognized; and that sometimes the problems result in the culling of obviously erroneous dates.

    [ January 23, 2002: Message edited by: Administrator ]
  2. Administrator2

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    Jun 30, 2000
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    The fact is that if you look at published dates the overall consistency is very, very high--most creationists tend to focus on the 5-10% of dates which do not fit the pattern while failing to offer much of any explanation for the pattern itself. Often there is an attempt to handwave it away by saying that mainstream scientists "fudge their results" by throwing away dates that don't match their expectations, but I would argue that the degree of consistency is too high for this to be remotely plausible--if rocks really dated in an essentially random manner, then to get the level of agreement found in published research you'd have to be throwing away hundreds of "bad dates" for every good date you kept. This just isn't believable on financial grounds, and more importantly, on psychological grounds: there is no way that scientists could rationalize away throwing out this many dates. The only alternatives I can see are:

    1. rocks really do date in the overwhelmingly consistent manner seen in published research
    2. There is a conspiracy of conscious deception on the part of scientists

    I really don't think there's any middle ground here. But so I'm not just making unsupported assertions, I'll give some examples of the degree of consistency found in radiometric dating, which as I said cannot plausibly be explained by mere "fudging" on the part of scientists. For instance, here's an article by radiometric dating expert
    G. Brent Dalrymple:
    Radiometric Dating Does Work!

    In it, he goes through a number of examples of objects dated by multiple laboratories, using multiple radiometric dating techniques, all giving very close agreement. For example, tektites from the K-T boundary (believed to have been created in the impact that killed the dinosaurs) were dated by 3 different techniques, by 6 different laboratories, and using tektites found at 5 different locations. You can see the results in the table at the bottom of the page. 25 different date estimates were obtained, from a total of 187 different analyses; all gave dates between 63 and 66 millions of years old. As I said before, if you assume that radiometric dates are essentially random and that scientists create the illusion of agreement by throwing away dates they don’t like, it seems you’d need hundreds of dates being thrown away for every "good" date they reported.

    Here’s an article which makes a similar point:
    How Can Woodmorappe Sell Us a Bill of Goods if He Doesn't Know the Costs?

    This article analyzes some claims by leading creation scientist John Woodmorappe, who tried to show that even if you assume dates are pretty much random, if enough dates are obtained at least some will agree, so maybe scientists are just throwing everything else out. The author explains why this is ridiculous—it would require something like 97.9% of all results to be thrown out, which would be prohibitively expensive, not to mention that no working scientist who was not intentionally trying to commit fraud could justify throwing out this much data. The author also goes through some specific examples to show how many random dates you’d have to go through to get this degree of agreement, like this one:

    Now, Woodmorappe has the full responsibility for either renouncing his accusations or demonstrating through appropriate economic and statistical evaluations of real examples from the literature (such as Baadsgaard et al., 1993) that his carnival game is both financially and scientifically feasible. Nevertheless, we'll perform a few more calculations to further evaluate his Lottery Game. First of all, let's eliminate the "first try" restriction on Woodmorappe's carnival game and estimate the minimum number of analyses Baadsgaard et al. (1993) would probably have to run and how much money they would have to spend to just randomly obtain 20 laser Ar-Ar results of 72.0 to 72.9 million years. Of Woodmorrappe's four "quasi-Monte Carlo" distributions, the "short-running log-linear distribution" has a mean date of 50 million years, which most closely approaches the desired results of 72.0 - 72.9 million years. With a log-linear distribution, there are equal probabilities that a "date" will fall into one of the following ranges: 1 million to 10 million, 10 million to 100 million, 100 million to 1000 million and 1000 million to 10,000 million, etc. (Woodmorappe, 1999, p. 87). Woodmorappe (1999, p. 87) argues that most published radiometric dates fall between a few million years up to 2500 to 3000 million years.
    Considering these variations, Woodmorappe (1999, p. 87-89) developed two log-linear distributions, one with arbitrary "short range" limits of 1 to 2500 million (logs 6.00 to 9.40) years and the other with a longer range of 10 million to 3500 million (logs 7.00 to 9.54) years. According to Woodmorappe (1999, p. 87, 89), the "short-running" log distributions are more "applicable" to K-Ar "dates," whereas methods with longer half-lives (Rb-Sr, Sm-Nd, and U-Pb) are supposedly better represented by the "long range" log distributions.

    Because of the similarities between Ar-Ar and K-Ar dating, the 20 Ar-Ar dates in Baadsgaard et al. (1993) were evaluated with Woodmorappe's "short-running" log-linear distribution. A Microsoft ExcelTM spreadsheet was used to estimate the MINIMUM number of random analyses that would probably be required to produce 20 Ar-Ar "dates" between 72.0 and 73.0 million years. It is fully recognized that the random number generator in ExcelTM may not be state of the art. Nevertheless, this study will give a reasonable idea of how much money Baadsgaard et al. (1993) had to spend if Woodmorrappe's Lotto Game is correct.

    A total of 100 random number sets were generated. Each set contained 5000 "random dates" based on Woodmorappe's short running log-linear distribution. After reviewing the contents of the 100 sets, the MINIMUM number of random "analyses" that were required to produce 20 "dates" between 72.0 (log 7.857) and 73.0 (log 7.863) million years was 3,775. As mentioned above, a typical MINIMUM cost for ONE laser Ar-Ar analysis is US$20. If Woodmorappe's shell game is correct, Baadsgaard et al. (1993) had to spend AT LEAST $75,500 for just 20 Ar-Ar dates, which is ridiculously expensive and intolerably wasteful. Of course, YECs could always accuse Baadsgaard et al. (1993), Baadsgaard et al. (1988), Queen et al. (1996), Montanari et al. (1985), Foster et al. (1989), and others of just fabricating their excellent results. However, such accusations would be baseless and insolent attacks on the integrity of these reputable scientists.”

    Here’s a followup to that Woodmorappe article by the same author:

    Hiding the Numbers to Defame Radiometric Dating: A Few Examples of the Many Misused References in Woodmorappe (1999)

    And here [] is a detailed critique of a paper by Woodmorappe, written by our very own Steven Schimmrich, along with a response by Woodmorappe here []
    and a counter-response by Schimmrich here [].

    Finally, here’s an article by ex-creationist Glenn Morton, which talks about Woodmorappe’s famous list of "bad dates":

    Some more pages on the consistency of radiometric dates, both with each other and with non-radiometric dating techniques:
    Consistent Radiometric Dates

    An Essay on Radiometric Dating --See section V—"Independent Checks on Radiometric Dating"

    Radioactive Minerals: The Ultimate Natural Clock
    --Near the bottom of the page, the author looks at independent dates found for the Amistoq Gneiss in Greenland, and estimates a 1 in 50^15 chance that such consistent results could be obtained by chance. Also notes that of the rocks obtained by the Apollo mission, which were subjected to great scrutiny, all gave dates of 3.9-4.5 billion years old, most dating at about 4.0 billion years.

    How Old is the Earth: Dating Methods
    --Notes that the order of the strata based on the geological column matches their order based on radiometric dating, which would be astonishingly lucky if radiometric dates were really random:

    The odds of arranging the Precambrian era, the seven geologic periods of the Paleozoic, the three periods of the Mesozoic, and the two periods of the Cenozoic in their proper order by pure chance are 6.2 billion to one. And, when you consider that each period can also be divided into "upper, middle, and lower," the odds of arranging them in the correct order by pure chance become astronomical. Radiometric dating has passed that severe test! It has correctly placed the Cambrian between the Precambrian and the Ordovician, the Ordovician between the Cambrian and the Silurian, the Silurian between the Ordovician and the Devonian, and so forth.

    Also see the bottom section, "Questions for Creationists," which talks more about the problems that radiometric dates pose for young-earth believers.

    Finally, as an all-purpose reference, here’s a nice page full of links on radiometric dating:
    A Radiometric Dating Resource List

    It appears that Karen has simply condensed and closely paraphrased the sequence of events that is recounted in Lubenow's book Bones of Contention about the KBS Tuff. There is apparently no attempt to independently corroborate any of his claims--she simply accepts them as written. So in fact, it is not Karen's account at all.
    Which is a shame, really, because much better analyses of the affair are available, and Lubenow simply misses a lot of information and misinterprets or fudges what he does have.

    For more complete accounts, see Roger Lewin's book Bones of Contention, in which he gives a tighter and more balanced sequence of events and actually talks to virtually all the people involved, and
    Brown F. 1994. Development of Pliocene and Pleistocene chronology of the Turkana Basin, East Africa, and its relation to other sites. In P. S. Corruccini & R. L. Ciochon (eds.), Integrative Paths to the Past: Paleoanthropological Advances in Honor of F. Clark Howell. Englewood Cliffs:prentice Hall, pp.285-312.

    This latter has the great advantage of putting the KBS Tuff controversy into the context of Koobi Fora, Lake Turkana, and the surrounding localities as a whole. This broad context of dating, stratigraphy, and correlation is universally missing from creationist accounts of this issue, as if the *only* site of any importance at Koobi Fora was the KBS Tuff, when it was only one of at least 9 dated tuffs in the Koobi Fora Formation, most of which marked fossiliferous members. In this wider context, it is simply erroneous to claim that there was no real way to determine which dates were "good" or "bad", as Lubenow tries to.

    Just a couple of examples, for space's sake:

    First, he misunderstands the nature of reworked tephra. Almost *all* of the datable tuffs at Koobi Fora are reworked; this does not preclude obtaining uncontaminated samples, since it was apparently easily done for a number of them.

    The sequence of events is misleading. Unless one is paying close attention, one might assume that a number of papers with "firm" dates had been published before ER 1470 was found (in 1972), when in fact only a single paper (Fitch and Miller 1970) was.

    The Maglio paper did not "confirm" the Fitch and Miller date, in fact it was ambiguous, and Lubenow knows it. He coyly notes "some problems" with it; it was, in fact, an anonymous author in the accompanying News and Views article who "confirmed" Fitch and Miller's date. What Lubenow left out was the fact that Vincent Maglio agreed with Basil Cooke, who, as early as 1970, noticed that the faunal sequence at the KBS Tuff localities did not accord with the well-studied and dated faunal sequences at Omo and at Bed I of Olduvai, this latter having been radiometrically dated with no problems as early as 1965 (it should be noted that, in 1965, F. Clark Howell began a program of radiometrically dating strata at Omo *before* fossils were found. The Shungura Formation at Omo is the closest important locality to Koobi Fora and shares many of the same tephra). Problems with the date were noted before ER 1470 was ever found.

    Fitch and Miller could never replicate that 2.61 my date with any consistency. However, far from "tossing out" anomalous results, in 1973 they presented their efforts at a conference: 41 measurements which ranged from 223 my to 0.91 my. Seven approached 2.61 my while 9 approached 1.9 my (the date now known to be true). The problem was that they could never adequately explain *why* they stuck with 2.61 my; while Leakey might have been happy that they did, others who had no personal stake in the outcome (such as Brent Dalrymple) could make no sense of their methods or results (or their explanations of the anomlaous dates, for that matter). Likewise, in 1975, Curtis et al. also published their spread of dates, but demonstrated detrital contamination for the old ones (rather than merely claiming it, as Fitch and Miller did).

    There are a number of other omissions and distortions.

    The reasons for the problems with the KBS Tuff are numerous and complex. Some indeed involved egos and high hopes. But there is plenty of evidence that the difficulties predated the ER 1470 finds, and that enough individuals were involved who were *not* connected to either Johanson or Leakey. The fact that "anomalous" dates were *not* thrown out is right in the published primary literature. Lubenow (and by extension Karen) only succeed in distorting the story with their selective use of "facts". The fact that one can find these "anomalous" results published seems to contradict Karen's claim that failure to publish "anomalous" dates is common.

    Originally posted by HRG/alter ego:
    To measure the mass of charged particles, one uses mass spectrometers (essentially via the curvature of the orbit in a magnetic field, which involves rather elementary quantum mechanics).

    Why quantum mechanics? Special relativity should be all you need.

    I agree. But why not quantum mechanics (where you can treat the magnetic field in a mathematically appealing way as a connection form, just for the heck of it) ?

    Joe, I am not going to deal with the data unethically when I have been working on this article this afternoon, and I don't think I could get away from what the author is saying enough to present it without referencing that material at least indirectly. At it is not mine to reference. Would you want someone who was reviewing one of your papers to use material in it to support a point they were making somewhere before your paper was published?

    However I did ask you on another thread if it was not true that samples submitted to labs for analysis (radiometric dating) had to have estimated dates submitted as well. You avoided the issue by saying you did all your own work. Well and good. That did not answer the question however. Others stated that it would be too expensive to do otherwise and gave other excuses.

    But the fact remains that a date is normally requested/required. And the only reason for this is so that 'anomalous' dates which may appear can be discarded so that a reasonable match can be made. This alone gives credence to the statement that dates are thrown out.

    As far as the mass of the electron goes, Birge's measurement in 1929 (Rev. Mod. Phys. Vol. 1:59) was 8.99425. In 1932, he upped this (Phys. Rev. Vol 40, p. 228) to 9.0351. Two years later (Rev. Mod. Phys. 12, p. 82) Birge again revised it to 9.1066. By 1952, Cohen and DuMond (Rev. Mod. Phys. 25:3, p. 691) listed it as 9.1085. But by 1986 (Codata Bulletin 63), the electron rest mass was given by Cohen and Taylor as 9.1093897.

    A graph of all the data points shows a consistent trend upwards, leveling out about 1980.

    I have also referenced for Holloway before concerning the way the mass of the electron is figured in SED physics -- it is by the volume taken up in terms of the zitterbewegung, or jittering motion, involved. Granted, that is not quantum physics, but it is solid physics. Whether or not he likes it is of no import.

    Originally posted by HRG/alter ego:
    I agree. But why not quantum mechanics (where you can treat the magnetic field in a mathematically appealing way as a connection form, just for the heck of it) ?

    You thus illustrate the difference between a mathematical physicist and an experimentalistt who tracks particles in a lab.

    Reemember, Helen, you made this accusation that dates are thrown out prior to publication.
    When challenged, you brought up a bunch of published ages. Now, you are retreating behind a veil of 'pre-pub' secrecy. I am not playing the games here. I want you to support your assertions.

    No lab "requires" an estimate and if they want one you are free to say "no."
    Second, if an estimate is asked the real only reason is in case some kind of calibration has to be done. It has nothing to do with suppressing dates, your delusions of radiometric conspiracies notwithstanding. If all these discordant dates are out there, who paid for them all? And if they are suppressed, how do you find out about them all.

    I'm having trouble keeping track of all these threads and may have missed something -- this post deserves more attention than I can give it right now -- but anyway, one thing to keep in mind is that C14 dating is not absolute but is calibrated based on assumed C14 production in the atmosphere. If it was calibrated based on varves then the agreement is not surprising. Another thing is that varves are suspect as well. They are smooth with little evidence of life -- not your typical pond by any means. It would require really special conditions to produce them and I think there is even some debate about geologists about what they are. I recall a study from Loma Linda in which varves between 2 layers were counted and should have given the same count but didn't indicating they do not measure passage of time.

    As for radiometric dating, what mainly concerns me is dating of life and here there are not many places where dating can be done, maybe 800 in one reference I saw. Almost all of these are K Ar dating and so one mainly has K Ar dating agreeing with itself. Snelling had a very long article about circulation patterns of Ar that discussed this issue. It's not an easy matter to see what the pattern is among the dates because if a particular formation or mineral is considered to be unreliable for dating then fewer dates on it will be done, biasing the results.

    I am assuming when you say 'life' you are referring to human evolution?
    Ar-Ar dating is now used as is thermal ionization spectrometry, magnetostratigraphy for establishing the ages of hominid sites.

    Helen brought up a point about data stuck in a lab drawer because it was bad. Although never directly stated, the innuendo was that scientists hide bad data. As you also know, I have acknowledged that not everything in nature works (one reason for extinctions and dead ends in biology!). Since I am packing up my lab for a move, I thought I'd do a quick check of how much data I have sitting in a lab drawer. I have approximately 22 age determinations currently unpublished. Of those 22, only 8 are problematic and the others should get published next year if I get my booty in gear. The 8 problematic ages are simple problems (4 Ar-Ar and 4 Sm-Nd). The Ar-Ar data clearly show excess argon and the Sm-Nd are all over the place yielding ages ranging from futuristic to older than the solar system. These 8 ages are published in my dissertation, but not in the formal literature. However, these ages are now going to be discussed and presented in a paper that will be submitted in about 3 months. That means all my geochronologic data will be 'out of the drawer' in the next year or so. In terms of paleomagnetic studies, I have about 10 studies that yielded nothing but scattered data due to the magnetic mineralogies and domain sizes involved. These studies will likely remain in the drawer unless I can find someway to incorporate them into related studies that work. It is my general experience that we all attempt to publish the good, the bad and the ugly if for no other reason than to try and save the next person from repeating the same errors. I also did a quick estimate on the percentage of 'anomalous' ages I have worked on. It turns out to be less than 10%. I think a 90% success rate is pretty good for work in generally unexplored regions. How is success defined? Well, when different isotopic systems give consistent results and when those results are supported by independent methods (paleomagnetism) that do not violate stratigraphic or intrusive relationships--the results are successful.

    Joe, I can’t reference work I am editing and proofing for another author. So I asked for some help. Some has come in and there should be more tomorrow. But for tonight, this will suffice:

    McKee, B., Cascadia: The Geologic Evolution of the Pacific Northwest, McGraw-Hill, New York, p. 25, 1972.

    "One might imagine that direct methods [radiometric dating] of measuring time would make obsolete all of the previous means of estimating age, but these new "absolute" measurements are used more as a supplement to traditional methods than as a substitute. Geologists put more faith in the principles of superposition and faunal succession than they do in numbers that come out of a machine. If the laboratory results contradict the field evidence, the geologist assumes that there is something wrong with the machine date. To put it another way, "good" dates are those that agree with the field data."

    [Question -- what do you suppose happened to all the 'bad' dates?]

    from the Abstracts of the Eighth International Conference on Geochronology, Cosmology, and Isotope Geology, Jagoutz, E., "Isotopic systematics of metamorphic rocks," 1994, p. 156

    "Garnet and clinopyroxene form a common mineral association in metamorphic rocks. Sm/Nd is partitioned between these two minerals in a way that this isotopic system should give ideal possibilities for age measurements. Only in a few cases geologically meaningful ages were obtained. In the majority of cases the ages are clearly off and the data disappear in a lab-datafile."

    Prothero, D.R., and Schwab, F., "Sedimentary Geology", 1996, W.H. Freeman and Co., p. 575

    "The example of the Koobi Fora and related formations of East Africa points out a number of problems typical of this kind of study. The radiometric dates provide the numerical ages, but they are subject to many types of error and so had to be redone many times in several laboratories by three methods over 15 years before all the results were consistent and undisputed."

    [Question -- what do you suppose happened to all the 'wrong' dates?]
  3. Administrator2

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    Jun 30, 2000
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    re: McKee, B., Cascadia: The Geologic Evolution of the Pacific Northwest, McGraw-Hill, New York, p. 25, 1972.

    ANOTHER PUBLISHED REFERENCE?? You said you had evidence to show that dates were tossed prior to publication! It's interesting that this is from 1972! Where is the evidence showing that most bad dates are thrown out prior to publication!

    [Question -- what do you suppose happened to all the 'bad' dates?]

    What 'bad dates'? The author provides no examples of bad dates that are tossed out! Give it up Helen, you've made an accusation you cannot support.

    Re: the Abstracts of the Eighth International Conference on Geochronology, Cosmology, and Isotope Geology, Jagoutz, E., "Isotopic systematics of metamorphic rocks," 1994, p. 156

    You're getting better here, but once again this refers to a specific system and a specific accusation that the author does not back up with data. At best you are guilty of repeating idle gossip. One abstract does not qualify your statement, but I commend you for bringing forth something! I also hate to bring the bad news to you, but the Sm-Nd dating of garnet and cpx has improved considerably since 1994 when this ABSTRACT was written. I happened to work on Sm-Nd dating of cpx in 1992 under some of the people responsible for developing and refining the Sm-Nd method (Klaus Mezger, Alex Halliday and Gareth Davies). We produced a number of 'bad ages' that are reported in my dissertation and in a forthcoming paper discussing a whole suite of bad ages on the Kisii lavas. In fact, far from hiding these ages, we discuss the problems inherent in dating some rocks. How do we know there are problems? We can see it in the behavior of the systems.

    Here's a good example of that:

    Complex Sm-Nd and Lu-Hf isotope systematics in metamorphic garnets from the Isua supracrustal belt, West Greenland
    Author(s): Blichert-Toft, Janne (Ecole Normale Superieure de Lyon, Lyons, France); Frei, Robert
    Source: Geochimica et Cosmochimica Acta, September 2001, Vol. 65, Issue 18, pp. 3177-3189
    Publisher: Pergamon : Oxford, International
    Country of publication: International
    Publication date: September 2001
    Language: English
    Major Categories: (03) Geochronology
    Subject(s): absolute age; actinides; allanite; amphibolite facies; Archean; Arctic region; cerium; dates; epidote group; experimental studies; facies; garnet group; geochemistry; Greenland; inclusions; Isua Belt; Lu/Hf; metals; metamict minerals; metamictization; metamorphic rocks; metasomatism; mixing; nesosilicates; orthosilicates; Precambrian; rare earths; silicates; Sm/Nd; sorosilicates; supracrustals; thorium; trace elements; upper Archean; West Greenland
    Abstract: Combined Sm-Nd and Lu-Hf isotope analyses of metamorphic garnets from the Earth"s oldest oceanic crustal sequence (the Isua supracrustal belt, West Greenland) yield errorchrons with apparent late Archean (2.8 Ga) crystallization dates. This contrasts with field and other geochronological evidence that link garnet growth to an early Archean (3.7 Ga) metasomatic-metamorphic event, but agrees more closely with the timing of a regional thermal overprint known to have affected both the Isua supracrustal belt and adjacent gneisses. Sm-Nd geochronological evidence presented here shows that the garnets were never reopened after garnet growth. The apparent partial reopening of the Sm-Nd isotope system within bulk garnets is instead explained by variable resetting of metamict allanite inclusions and their differing relative abundances within the garnet hosts. Allanite precipitated from metasomatic alteration fluids that percolated through the rocks during the emplacement of tonalite sheets. While light-rare-earth-element-rich allanite inclusions can affect the Sm-Nd system of bulk garnet, its low heavy-rare-earth element and Hf contents produce no measurable effect on the Lu-Hf system. Rather, the abundant common Hf in zircon, also present as inclusions in the garnets, affected the Hf budget to the extent of significantly lowering apparent Lu-Hf garnet ages. Whether the zircon inclusions are older (i.e., inherited) or contemporaneous (i.e., metasomatic) with the host garnets cannot be resolved with the present data. Despite the complications caused by inclusions in the garnets analyzed here, this study shows evidence for a metasomatic event at 3.7 Ga and a widespread resetting event at 2.3 Ga, but no evidence for a meaningful geologic event at 2.8 Ga. The 2.8 Ga Sm-Nd and Lu-Hf correlation lines obtained for the Isua garnets are interpreted as mixing lines between, respectively, metamict allanite and metamict zircon, both reset at 2.3 Ga, and garnet crystallized at 3.7 Ga. This study emphasizes the need for caution in the interpretation of Sm-Nd and Lu-Hf geochronological data involving garnets. Highly resistant inclusions, such as zircon, are unlikely to re-equilibrate with their host mineral during later tectono-metamorphic overprints and can severely bias parent-daughter element budgets. Likewise, metamictization of Th-U-rich inclusions (such as allanite and some zircons) within host minerals (in this case garnet) renders the inclusions increasingly prone to open-system behavior during later thermal events, leading to apparent initial isotopic disequilibrium between the inclusion phase and its less affected host. Finally, an initial epsilon (sub Nd) value at 3.7 Ga of -14 for garnets not containing allanite inclusions suggests the presence in the Isua area of very early differentiated crust.

    Furthermore, if Jagoutz is so down on the method, why would he continue to use it:

    The interrelation between core and rim of individual chondrules from the different meteorites in terms of Sm-Nd isotopic system Author(s): Krestina, N. (Max-Plank Institute of Chemistry, Department Cosmochemistry, Mainz, Federal Republic of Germany); Jagoutz, E.; Kurat, G. Monograph title: Lunar and planetary science, XXX; Papers presented to the Thirtieth lunar and planetary science conference
    Author(s): Anonymous
    Source: Abstracts of Papers Submitted to the Lunar and Planetary Science Conference, 1999, Vol. 30
    Publisher: Lunar and Planetary Science Conference : Houston, TX, United States
    Sm-Nd and Rb-Sr isotopic chronology and cooling history of ultrahigh pressure metamorphic rocks and their country rocks at Shuanghe in the Dabie Mountains, central China Author(s): Li Shuguang (University of Science and Technology of China, Department of Earth and Space Sciences, Hefei, China); Jagoutz, Emil; Chen Yizhi; Li Qiuli Source: Geochimica et Cosmochimica Acta, March 2000, Vol. 64, Issue 6, pp. 1077-1093
    Geochemistry and age of ultrahigh pressure metamorphic rocks from the Kokchetav Massif (northern Kazakhstan) Author(s): Shatsky, V. S. (United Institute of Geology, Geophysics and Mineralogy, Novosibirsk, Russian Federation); Jagoutz, E.; Sobolev, N. V.; Kozmenko, O. A.; Parkhomenko, V. S.; Troesch, M.
    Source: Contributions to Mineralogy and Petrology, November 1999, Vol. 137, Issue 3, pp. 185-205
    Publisher: Springer International : Heidelberg-New York, International
    Country of publication: International
    Publication date: November 1999
    Language: English
    Major Categories: (02A) General geochemistry; (05A) Igneous and metamorphic petrology Subject(s): absolute age; alkaline earth metals; Asia; Central Asia; chemical composition; Commonwealth of Independent States; dates; garnet group; high pressure; isotope ratios; isotopes; Kazakhstan; Kokchetav Massif; mantle; metals; metamorphic rocks; neodymium; nesosilicates; orthosilicates; P-T conditions; Precambrian; pressure; radioactive isotopes; rare earths; samarium; silicates; Sm-147/Nd-144; Sr-87/Sr-86; stable isotopes; strontium; U/Pb; Zerenda Series

    Re: Prothero, D.R., and Schwab, F., "Sedimentary Geology", 1996, W.H. Freeman and Co., p. 575
    They were published! This is why Prothero is able to discuss the issue! You claim they are all buried in a drawer and the best evidence you can come up with is an abstract that merely repeats gossip. Yes, bad ages are sometimes produced. However, your mistake is in thinking that 'a bad age' means it did not agree with the authors assumption about the age. Remember, there are bad watches and clocks manufactured every year, but we still rely on them and can tell when they are not working properly. You would say 'all watches are unreliable'. The rest of us would say 'nature and manufacturing' both have flaws, but in general they do a good job.

    And what if this relatively new radioisotope dating method (Sm-Nd) had failed it's experimental phase? In addition to what has already been said [the bad dates would be published, method's use would cease] a key point is that this failure would not seem to touch well-established radio dating methods. How could such failure be useful in a substantive YEC argument? Pavel

    Well, it would be if, among other things, nobody bothered to publish stuff showing that
    a) it was problematic and
    b) that its problematic nature could not be explained.

    The difficulty creationism has is that sooner or later, somebody is going to try and get a publication out of at least one of those two issues somehow. Research costs money, and the imperative to publish is quite real, and those two things together make sure that if there is a systematic problem, somebody (somewhere) will make hay out of it. In every field there are dozens of young bloods, all full of juice and trying to show that the fogeys are wrong: its the stuff that potential careers are made of.

    But the problem is, most of those fogeys were young bloods themselves, ya know? The only way you make it is to

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