Date: 22 Feb 94 00:48:10 To: All Subject: Hovind on Radiometric Dating Here's another page

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Date: 22 Feb 94 00:48:10 From: Rich Fox, Univ To: All Subject: Hovind on Radiometric Dating From: (Rich Fox, Univ of South Dakota) Organization: The University of South Dakota Computer Science Dept. Here's another page of Hovind nonsense, for comment. Once again, I'll [Lippard] collect replies and send them to Babinski for his debate. Several Faulty Assumptions Are Used in all Radiometric Dating Methods. Carbon 14 is used for this example: 1. Atmospheric C-14 is in equilibrium. This assumption is wrong. It has been shown that the amount of C-14 in the atmosphere is still increasing. Libby in 1952 wrote (in _Radiocarbon Dating_) that cosmic ray intensity over the past ca. 20000 years probably fluctuated. He did assume that intensity averaged over ca. 1000 years had not fluctuated significantly. He therefore concluded that atmospheric C14 has been in equilibrium (production = decay). By 1958 the assumption was shown to incorrect and today there are detailed, refined corrections based on dendrochronology (discussed below) in place. The bottom line: equilibrium is not assumed and variation in equilibrium is adequately controlled. Hovind's "still increasing" is informative. Actually, variation in cosmic ray intensity over time has produced cyclical fluctuations in the C14 reservoir. Judging from "still", he sees the recent past as a moment in a uniform, linear accumulation of C14 from zero to equilibrium. Hovind's view is classic uniformitarianism, a view which most creationists decry (but, like Hovind, unkowingly use). 1 (con't ). It has been estimated that the C-14 in the earth's atmosphere would reach equilibrium (the formation rate would be equal to the decay rate) in about 30,000 years. Research indicates that the amount of C-14 is still increasing and is only 1/3 of the way to equilibrium. This evidently is an attempt to invalidate the alleged equilibrium assumption. So far as I can tell, the 30,000 "estimate" derives from Henry Morris's (Scientific Creationism, p. 161, 164) argument from incredulity, and nowhere else. Morris arbitrarily limits C14 dating to 29000 years ago, because at that point only 1/32 of the original C14 content remains in the dead organism. Morris thinks its "doubtful" that any smaller amount can be reliably measured. They can and have been - up to 40,000 years for conventional C14 dating, and 50,000 years for accelerator mass spectography (AMS). Isotopic enrichment offers potential to 70,000 years. 1 (con't). This indicates a young earth (less than 10,000 years). Nope. Even if true, it would only indicate a young atmosphere. 1 (con't). This also nullifies all dates obtained by C-14 decay. Using the putative water vapor canopy, most creationists argue that "pre-flood" C14 dating is bogus and that "post-flood" dating is legit. You may want to ask Hovind why they are wrong and he is correct? 1 (con't). As the earth's magnetic field decays, more cosmic radiation is allowed to penetrate into our atmosphere. 16 clicks (on a geiger counter) per minute per gram (16 DPM/Gc) is typical in living objects today. Plants and animals that lived on the earth a few thousand years ago would have had much less C-14 in their body to start with. This would make them appear to be thousand [sic] of years older than they really are. Here again Hovind implicitly uses uniformitarian reasoning. Scientists know that earth's magnetic field is decaying. Creationists take this to mean that the field has decayed linearly from a maximum value at the beginning. They ignore (suppress) the fact that periodic polarity reversals reset the field and decay starts in again. So decay is cyclical, not linear. There is a cause\effect relationship between magnetic field intensity and cosmic ray intensity (latitudinally as well as temporally). Basically, the weaker the field, the greater the cosmic ray intensity, thus more C14 in the atmosphere and hence in organisms. More C14 gives younger dates. The reverse is true for older dates. I have no idea how the geiger counter clicks bear on the issue, except perhaps as a smokescreen. In C14 dating, organic samples that are "a few thousand years" old most assuredly do not appear "older than they really are." Based on dendrochronological calibration, a post-1500 BC organic sample is actually _younger_ that its C14 date (up to a century). A pre- 1500 BC sample is actually _older_ than the C14 date derived from it (up to 800 years older). There is no doubt about this. 2. Decay rate remains constant. This assumption has been shown to be in error many times. Several factors affect the rate of C-14 decay. The 11 year solar sun spot cycle is one such factor. Since the rate of decay is not constant, no dates obtained by C-14 can be trusted. The decay rate of C14 has to be a constant. No one has ever shown the assumption to be in error, even using "sun spots". Ask for the sun spot citations. I know of none. However, the constant cannot be deduced from first principles. It must be measured by experimentation, and it has been. Experimental error results in various half-lifes (the exponential decay rate). Libby obtained a weighted average of 5568 +/- 30 from three measurements, namely 5580 +/- 45; 5589 +/- 75; 5513 +/- 165. Recent experiments have resulted in a weighted average of 5730 years, which by convention is used today. Nothing in these calculations renders the dating technique untrustworthy. 3. Initial amount of C-14 can be known. This assumption has been demonstrated to be wrong many times. Initial amount is not assumed. Dendrochronological calibration corrects for variations in initial amounts of the parent (C14). 3 (con't). Different parts of the same sample often yield different ratios. Various living samples give very different ratios. Though confused, Hovind here uses an argument from anomaly. The structure of this argument is > there are exceptions, therefore the technique is bogus. The premise is true, but the conclusion does not follow. Different parts of a mollusk shell, for example, yield varying dates. This is because mollusks ingest C12 mostly from a terrestial environment with much carbonate, thereby skewing the C14/C12 ratio (isotopic fractionation). Physicists are well aware of this, and they figured it out, not creationists. That is why archaeologists seldom use dates from shell (although the conchiolin portion of shell is useful). No such problem exists for charcoal because plants derive most of their carbon from photosynthesis (atmospheric carbon). 4. The sample being tested has not been contaminated. This assumption is very difficult, if not impossible to prove. Parent or daughter products could have leached in or out of the sample. Many lab tests have confirmed that this does happen. No lab ever assumes a sample is uncontaminated. The sample is closely examined. If contaminated, various procedures are available to clean the sample. Rarely does contamination prevent an accurate assay. When a C14 date is considered anomalous, it is usually so because the archaeologist has been careless (e.g., misread the stratigraphy). 5. Accurate measurement of C-14 in sample. This is not reasonable to assume. The amount of C-14 in the atmosphere today is less than one part per million. Claiming to be able to measure accurately to 7 decimal places is not reasonable. This is the argument from incredulity. It is meaningless. The fact that Hovind's mind can't conceive of several more decimal places than usual is his problem. 6. Shape of the curve of the line is known. This assumption is not rational. The oldest sample of independently known age is Hemaka, the Egyptian mummy from 2700-3100 B.C. To base a graph on such a small section of the curve is not wise. (Secular writers of antiquity tend to exaggerate ages so even these dates are suspect) Evidently Hovind thinks C14 dates are calibrated on a sequence (curve) of historical dates. They are not (though Libby originally tested his method, in part, with considerable success on historical objects of known age). They are calibrated from tree ring master charts (dendrochronology). An annular growth ring of known age is C14 dated. The discrepancy, if any, between the known date and the C14 date is noted. Many comparisons are obtained, and eventually a calibration curve can be constructed. Actually, the "curve" in detail is characterized by wiggles, the wiggles charting short term fluctuations in cosmic ray intensity, the curve charting the long term average variation. Further, Hovind seems to think that his historical curve is not "long" enough to establish a reliable "curve". But the length (in years) of a calibration curve, whether based on historical objects or tree rings, has nothing to do with reliability. If a reliable curve spans only 3000 years, it is accurate for those 3000 years. In any case, the oldest sample of known age is not Hemka (not to mention that a 2700-3100 range is not a calendrical age). The oldest sample of known calendrical age is an annular tree ring (bristlecone pine) which is 8681 calendrical years old. The bristlecone pine sequence is tied to the South German Oak sequence to obtain a calendrical date of 9209 +/- 10 years ago. Correlation of the tree ring sequences to adjusted Swedish varve dates provides a tentative calendrical date useful for C14 calibration at 13,300 years ago. 7. The geologic column is a base to calibrate the C-14 dates. This assumption is not wise. Here we find that Hovind has no clue about dendrochronological calibration. Either that, or he is, as creationists often are, guilty of supression. Whatever, the geologic column has nothing to do with C14 dating (although archaeologists use stratigraphy on a fine scale). 7 (con't). The entire geologic column is based on the assumption that evolution is true. This fictitious column (invented in the 1800's to discredit the Bible) does not exist anywhere in the world except in textbooks. Column based on evolution? Exactly the opposite occurred. The entire geologic column was in place decades before Darwin published his theory. His theory provided a satisfactory explanation for the nature of the column. Prior to that, all manner of non-Darwinian explanations were advanced, the most popular being catastrophism. Many devout and pious Christians (e.g., John Ray, Charles Lyell, William Smith, James Hutton, Georges Cuvier, Nicholas Steno, etc.) helped figure out the geological column. They certainly were not trying to discredit the Bible. They saw in nature another record of their God's handiwork, and they set out to read that record. The geologic column, or timescale, is constructed from regional and local sequences worldwide. Hovind's implicit claim that the geologic column must exist outside of textbooks in order to accurately represent earth history is entirely his. No geologist has ever made that claim (even John Morris) - or ever will. 7 (con't). Poly-strata fossils, missing layers, layers out of order, misplaced fossils, and layers in reverse order all invalidate the geologic column. (Watch seminar tapes #4-6 by Dr. Kent Hovind for more information.) Henry Morris also uses the "poly-strata fossil" argument. Sponges, for example, exist today and they are found as fossils in deep time. Therefore, fossils cannot be used to date (relatively) strata. This completely ignores at least two factors, 1) experts can and do detect variation in what look to be the same fossils distributed across multi-strata, and 2) the fact of index fossils - organisms of limited temporal duration and wide distribution. Missing layers, inversions, etc. are understood and recognizable by geologists, and have been for nearly two centuries. Phenomena not presently understood are not understood. Nothing more. The inability to understand does not invalidate earth history as known. Even more to the point, it doesn't prove Hovind's world view. So far I am not inclined to watch seminar tapes #4 thru #6 by Dr. Kent Hovind. I think I'd rather go down to the service station and watch the boys change tires. 7 (con't). _The assumed age of the sample will dictate which dating method is used since each will give a very different result._ Decidedly wrong. The nature of the material to be dated usually determines the method used. For example, organic remains can only be reliably dated by C14. Potassium argon dating is only useful on volcanic rocks. A given rock may be dated by several techniques (e.g., uranium series, strontium/thorium, KAr), each of which is independent of the other. In such cases, the independent techniques regularly yield statistically consistent dates. Who, pray tell, is Kent Hovind, and what does the Dr. before his name mean? Rich Fox, Anthro, Usouthdakota


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