Some Comments on Radiometric dating

From: allenroy (allenroy@peoplepc.com)
Date: Wed Jan 22 2003 - 19:12:06 EST

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    Allen wrote
    >1: There is a distinction to be understood between computing apparent
    >ages according to certain assumptions from scientific quantification of
    >an assortment of isotopes in rock, and the acceptance of those dates as
    >valid for the rock involved.

    Glenn Morton wrote:
    Allen, the very basis of dating is stratigraphy which involves the
    geometrical relationships between the various rock layers. Veins which
    cross-cut other rocks are emplaced after the rocks were in place. With
    sedimentary rocks, lacking geometrical evidence of overthrusting, the
    topmost rock is the youngest. Radioactivity can go wrong and does. If the
    dates violate the very laws of deposition, the laws of deposition take
    precedence. It is logical to do it that way.

    **[allen]Yes, Precisely; that is the heart of my thesis. Point 2 is
    "The dating process of rock units is subjective even when radiometric
    dates are available." Meaning subject to the laws of stratigraphy.
     And, being "subject to" means that isotopic dates are rejected or
    accepted depending upon other factors than the accuracy of the isotopic
    dating methods. (Point 1) And the fact that isotopic dates for the
    Uinkaret are rejected because they do not stratigraphically fit shows
    Point 3, "If any rock unit is believed to be young, then any old
    radiometric age is rejected, not as inaccurate, but as irrelevant to the
    age of the rock."

    I might make a note that the reason you know of bad dates is because the
    scientists do publish bad dates, contrary to many claims by the YECs.

    **red herring Whether scientists do or do not publish "bad" dates is
    irrelevant to my thesis. Whether YECs claim that or not is also
    irrelevant to my thesis.

    > I don't
    >know of any Creationary scientist who quarrels over the methodology,
    >accuracy and precision with which isotopes are measured and ages
    >computed. Most have, however, focused on the validity of assumptions of
    >radiometric dating.

    If they accept the validity of the measurements, then I would like to see a
    YEC explanation for why the ratios of various isotopes vary systematically
    with the stratigraphic position of the rock. Even when a young-earther goes
    through the literature looking for bad dates, one can still see this
    relationship. Isotope percentages vary according to the stratigraphic
    relations of the rocks.

    **I can do no better than Woodmorappe, 1999, "C. Stratigraphic Trends in
    Isotopic Dates," in Chapter 3 "Bogus Arguments for the Overall Validity
    of Isotopic Dating methods." in 'The Mythology of Modern Dating
    Methods," pages 18-23

    John Woodmorappe (1979) went through the scientific literature looking
    for radioactive dates which are 20% too old or too young. He specifically
    excluded from his search any date which matched the expected age. This
    type of selective editing is exactly what Young earth Creationists charge
    the Evolutionists with.

    **red herring What Woodmorappe did or didn't do and why is irrelevant
    to my thesis.

    http://www.glenn.morton.btinternet.co.uk/radchart.gif.
    [the] Above the 350 dates [from woodmorappe] are plotted . A perfect
    dating result should appear
    on the line. Note that there are more dates under the line than above the
    line. If radioactivity is producing dates which are too old, you would
    expect that there would be more dates above the line than below the line.
    What this proves is that if a radioactive date is wrong it is far more
    likely to be too young than too old! Young earth creationists need the
    dates to be too old if their viewpoint is correct.

    What is your explanation? Chemically, why is this?

    **First, your plot of computed verses expected ages illustrates Point 3
    -- if an isotopic date fits the expected date it is accepted, if not, it
    is rejected.

    **Second, Creationists completely reject all isotopic dates, so it is
    just as irrelevant for there to be too young of ages as too old of ages.
     We don't need for isotopic dates to be young, we don't need them at
    all--they are irrelevant.

    >This comes to my point. Just because the process of radiometric dating
    >is done with great precision and great care, that does not automatically
    >mean that the results are going to be accepted as valid. ... In the
    case of the
    >Uinkaret/Cardenas igneous rock, non-scientifically acquired data
    >actually takes precedence over the scientifically (technologically?)
    >acquired radiometric data. It is strictly observation and logic (not
    >scientific experiment) that shows that the Uinkaret must be younger than
    >the Cardenas. This fact outweighs the scientific data acquired through
    >the radiometric dating process.

    Why is it Allen, that when YECs like you claim great successes, you never,
    ever seem to acknowledge that someone has criticized the work you are
    presenting? Why is it that YECs only ever present one side of the question.
    You should be aware that Chris Stassen has written a critique of the methods
    Austin used to date the uppermost lavas and documented how Austin rigged the
    results.

    **I am fully aware of Stassen's article and as I noted in another reply
    to this thread, Stassen's criticisms are bogus. I remember when Stassen
    first wrote this article in part due to arguments we had been having on
    T.O. I wasn't impressed then and I'm not impressed now. He created a
    useless strawman [i.e. the rigged results] and appears to not have
    carefully read Austin's Grand Canyon book.

    Isochron methods apply to a single rock, or mineral in which
    several isotopic ratios are determined for that SINGLE mineral. Austin, it
    seems, used 4 different rocks from 4 different lava flows. This is not the
    correct way to do isochron dating.

    **As I noted elsewhere, the claim of the lava flows being non-cogentic
    is not based on the isotopic data. But simply because they are separate
    flows.

    Stassen says:
    "Before the Grand Canyon Dating Project began, in his 1988 Impact article,
    Austin admitted in print that the selected lava flows fell into two
    different stratigraphic stages. That is, the very information which he used
    to select the flows, also clearly indicates that they did not all occur at
    the same time. In his subsequent book (Grand Canyon: Monument to
    Catastrophe), Austin indicated that his five data points came from four
    different lava flows plus an extracted "phenocryst" (large mineral which
    likely formed in the magma chamber and was not molten in the lava flow). We
    had known from the Impact articles that Austin's samples were not all
    cogenetic; years later we find out by his own admission that no two of them
    are so. " http://www.talkorigins.org/faqs/icr-science.html#refaus88

    **As I pointed out elsewhere, Austin's five data points were not taken
    from Leeman, but were collected by Austin himself. Stassen is either
    ill informed or deliberately misleading.

    >So, Point 1 is: The acceptance or rejection of radiometrically acquired
    >ages for rock depends upon factors other than the science/technology of
    >radiometric dating. (The Uinkaret/Cardenas system is symptomatic of the
    >entire radiometric dating scheme).

    Point 1 through 3 should be the fact that YECs misrepresent things.

    **You have given no evidence that I have misrepresented the evidence.
     Lets see you take my arguments and expose them as illogical.

    Allen

    ---
    

    "I have been shown that, without Bible history, geology can prove nothing. Relics found in the earth do give evidence of a state of things differing in many respects from the present. But the time of their existence, and how long a period these things have been in the earth, are only to be understood by Bible history. It may be innocent to conjecture beyond Bible history, if our suppositions do not contradict the facts found in the sacred Scriptures. But when men leave the word of God in regard to the history of creation, and seek to account for God's creative works upon natural principles, they are upon a boundless ocean of uncertainty. Just how God accomplished the work of creation in six literal days, he has never revealed to mortals. His creative works are just as incomprehensible as his existence." Ellen Gould Harmon White, 1864



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