Tuesday, March 17, 2009

Radiometric Dating and Creationist Fraud

This is a post I provided to refute some arguments made by a YEC.
(This one helps with the Creationwiki web site.)
>> YEC:
>> No, Pasha. It is not disheartening at all. Not
>> when we already know that radiometric dating is
>> based on circular reasoning...
It's not circular reasoning at all!
Radioactive elements decay with a fixed half-life. Carbon-14, which has a relatively short half-life has been quite successfully correlated with tree rings. Certainly tests such as that confirm the validity of radiometric dating.
Moreover, radiometric half-lives don't change> in elements even when they are exposed to excessive heat, or even explosions.
Wikipedia explains it like this:
"In refutation of young-Earth claims of inconstant decay rates affecting the reliability of radiometric dating, Roger C. Wiens, a physicist specialising in isotope dating states:
"There are only three quite technical instances where a half-life changes, and these do not affect the dating methods [under discussion]":
"1. Only one technical exception occurs under terrestrial conditions, and this is not for an isotope used for dating. ... The artificially-produced isotope, beryllium-7 has been shown to change by up to 1.5%, depending on its chemical environment. ... [H]eavier atoms are even less subject to these minute changes, so the dates of rocks made by electron-capture decays would only be off by at most a few hundredths of a percent.
"2. ... Another case is material inside of stars, which is in a plasma state where electrons are not bound to atoms. In the extremely hot stellar environment, a completely different kind of decay can occur. 'Bound-state beta decay' occurs when the nucleus emits an electron into a bound electronic state close to the nucleus. ... All normal matter, such as everything on Earth, the Moon, meteorites, etc. has electrons in normal positions, so these instances never apply to rocks, or anything colder than several hundred thousand degrees. ...
"3. The last case also involves very fast-moving matter. It has been demonstrated by atomic clocks in very fast spacecraft. These atomic clocks slow down very slightly (only a second or so per year) as predicted by Einstein's theory of relativity. No rocks in our solar system are going fast enough to make a noticeable change in their dates. ..."
>> ...and an appalling lack of quality control that
>> would get a hospital laboratory shut down for
>> its pains.
Nearly all radiometric dating testing is done under very rigorous laboratory conditions.
As usual, you don't provide a reference but my guess is that you or some "creation-scientist" found one or a small handful of examples where the proper quality control procedures weren't followed and have assumed that ALL such testing> is flawed.
If so, that is a fallacious argument.
If you are going to make a valid argument, you must get a copy of the testing procedures from a reputable laboratory and show how they are flawed or show that they are typically not followed.
Of course you can't do that.
>> Steven A. Austin's "Excess Argon" paper told me
>> all I needed to know about radiometric dating
>> in current practice.
Typical fraudulent creationist argument noted.
First we need a little backgrond.
The Potassium - Argon radioactive decay sequence> has a half-life of 1.25 billion years. That's BILLION - 1,000,000,000 - years.
Any measurement system has an inherent error, generally based on the mechanism being used.
According to the University of Santa Barbara> at http://tinyurl.com/KARDATING, "the standard deviations for K-Ar dates are so large that resolution higher than about a million years is almost impossible to achieve."
So that's about a million years of variation based on a half-life of 1.25 BILLION years.
That's actually pretty good. It means that the error is less than 0.1% of the half-life. If you use this dating method in the way in which it is intended - VERY old rocks - and> you measure a rock of, say, 4.000 billion years you can be confident that the actual age falls between 3.999 and 4.001 billion years.
Note what happens if this error percentage is applied to dating methods using a different half-life. For example, C-14 has a half-life> of 5700 years. An error of 0.1% of that half-life would give an expected error of plus-or-minus only 5 to 6 years.
Radioactive decay is a process based on quantum mechanics it is therefore a random process. In large quantities, you can make quite accurate predictions. But that is not necessarily the case with small samples.
It's like what happens at a gambling casino. If you ask a casino owner to estimate the casino's gross profits over a long period of time such as a week or a month or more, the owner can do a surprisingly accurate job of that even if everything, including the slot machines, really are honest and yield truly random results.
But if you ask the owner of the casino if they will make a profit in the next five minutes, the answer is more problematic. The casino PROBABLY will make money over even such a short period of time, but it is a real possibility that a major payout due to a customer hitting a jackpot may have a significant impact over those few minutes. Over longer periods of time such things even out.
That's effectively the argument being made by these "creation-scientists". K-Ar dating has a half-life of 1.25 BILLION years. With a very young rock, even a few atoms can throw off the reading by hundreds of thousands of years or more.
With that background, let's look at Austin's> argument.
It is described in the article at> http://www.noanswersingenesis.org.au/blind_leading_blind_kh.htm titled "Blind Leading the Blind: Austin, Snelling and Swenson Misinterpret Dalrymple's K-Ar Dating of Historical Volcanics".
In summary the paper you cite relates to some data collected by G. Brent Dalrymple, a well-known geochronologist with 40 years experience, who is a pioneer in the identification of excess argon in igneous samples, and an outspoken critic of young-Earth creationism. As part of his seminal work on excess argon, Dalrymple (1969) dated 26 historical lava flows with K-Ar to determine whether excess argon was present. ("Historical" meaning> that they occurred within human history.) Of the 26 lava flows that were sampled and analyzed, 18 of them gave expected results - effectively an age of zero. That is, no excess 40Ar or 36Ar were present. Eight rocks yielded unrealistic dates, which were either too old because of the presence of excess 40Ar (5 of them) or too young (negative ages) because of the presence of excess > 36Ar (3 of them).
In seven of the eight cases, the error was on the> order of 100,000 years - hardly significant and well within the expected error of K-AR dating.
Only ONE reading had a larger error larger than that - 1.19 million years. That fell somewhat outside of the error expected for K-AR dating.
Even that one rock with the most significant error had very noticeable xenoliths (older rock contaminants that were incorporated into the magma as it rose through the Earth to the surface). These would be easily recognized by a trained geologist. Once the xenoliths were removed, the remaining matrix provided the expected date.
Note also that 3/8 of the errors resulted in readings that gave dates that were too YOUNG. Errors such as that would tend to favor YEC.
The fraud is evident. The conclusion of the paper, if anything, is that K-AR dating is BETTER than expected. After compensating for the xenoliths in the single anamolous rock, all of the rocks fell well within the expected error range for K-AR dating.
But, most people don't understand the expected error margin for K-AR dating. So if you tell them that some rocks relatively recently formed from volcanic eruptions had dates measured up to a MILLION years, they are astounded and immediately question the integrity of that testing.
Apparently YOU were fooled as well.
But, as they say, everything is relative.
The web site I referenced points to another example of the sort of carelessness so typical of "creation-scientists". It compared the papers from Snelling and Austin to the orginal data from Dalrymple and found numerous mistakes in both. For example, the rock with the largest error was listed at 1.19 million years in the original paper but at 1.4 million years in both "creation-science" papers.
As the article concludes:
"Because Austin's essay is older, we can probably assume that these copying errors originated with him. Rather than checking the accuracy and relevancy of Austin's quotations from Dalrymple (1969), Snelling and Swenson simply uncritically parroted and perpetuated Austin's mistakes in their later web essays. This is truly a case of the blind leading the blind!!"
I suggest that you find better resources to support your arguments.
"Creation-scientists" can be trusted to be frauds.
>> In case anyone has forgotten, or haven't read about
>> it yet, they sent five samples of dacite from the
>> Mount Saint Helens lava dome to Geochron Laboratories
>> and asked for a potassium-argon date. Geochron said
>> that those five samples were anywhere from five
>> hundred thousand to two point eight million years
>> old. Preposterous, of course; that dacite was ten
>> years old if it was a day.
You really need to provide specific references.
But the article that I believe you are referring to is refuted at> http://ncseweb.org/book/export/html/2519
The article identifies problems with Austin's work.
First, Austin sent young, low-potassium rocks to Geochron Laboratories. Such samples are very low in radiogenic argon, which is the isotope responsible for the radioactive decay that is the basis of the dating techniques. (This has already been explained above.) Although Geochron specifically stated that it did not want to deal with young, low-potassium samples, Austin sent them anyway and specifically stated in his paper that he did not reveal the origin of the samples. This "omission" can result in potentially large ranges of error in the results and also opens his research to ethical questions.
More importantly, Austin apparently dated some of the solid material that came up with the lava rather than the lava itself. Austin had mentioned that the lava contained xenoliths—pieces of solid rock that came up with the lava. As with the previous example cited above, such older rocks mixed in with young lava will,, unsurprisingly, skew the results to make them appear older than they really are.
>> But Austin didn't stop there.
He should have. He hasn't proven anything yet.
>> He and Humphreys and Vardiman and Snelling and
>> several other workers formed the "Radioisotopes
>> and the Age of The Earth" (RATE) Group. They
>> have published two volumes of their work. Now
>> if anyone here is genuinely interested in what
>> they found, you can buy those volumes at any
>> time from the online store at the Northwest
>> Creation Network.
Wikipedia has an article that refutes the claimsin this book as well. (See> http://en.wikipedia.org/wiki/Creation_geophysics)
Here's how it summarizes things:
"The scientific community points to numerous flaws in these experiments, to the fact that their results have not been accepted for publication by any peer-reviewed scientific journal, and to the fact that the creationist scientists conducting them were untrained in experimental geochronology.
The RATE project is seriously flawed in many other ways. The web site http://www.talkorigins.org/faqs/helium/zircons.html provides a detailed, if technical, refutation of each and every one of their claims.
>> For everyone's information, 770,000 years is not
>> much older than the apparently "youngest" rock
>> that the US Geological Survey has records of.
>> Haven't I already shared with everybody Snelling's
>> paper about the finding of the fossilized tree
>> buried in basalt in the Crinum Coal Mine
>> in Australia? Snelling and his team sent samples
>> of the wood to one lab and samples of the basalt
>> to two other labs (including Geochron). Guess
>> what? The tree "dated" at 40,000 years, and
>> the rock "dated" at over a million years.
Typical fraudulent creationist argument noted.
Here we have a common sense answer: lava comes out of the ground typically at 2000 degrees F. It has to be at LEAST 1500 degrees because that is the temperature at which basalt melts. If such lava surrounded a living tree, then the tree would not just instantly burn up, it would vaporize.
If you watch movies of Hawaiian and other lava flows, you see this sort of thing happen all of the time. When the lava hits the tree, it instantly bursts into flames and the tree is destroyed by that fire in a very short period of time.
Lava can't surround a living tree!! It simply isn't possible.
Clearly the only explanation is that the tree grew from a seed some time after the lava cooled. We should certainly expect the tree to be younger (and possibly MUCH younger) than the lava.
Note that the tree MUST be younger than the lava. There is no other rational explanation.
Without pictures or anything else to refer to it is difficult to surmise precisely what happened. But it is surely not impossible for a million-year old lava flow to have a hole in it through which a tree couldgrow. Clearly that is what happened.
>> Again for everyone's information, Geochron doesn't
>> do potassium-argon dating anymore. I'll let
>> everyone guess why.
I doubt that it has anything to do with these examples of creationist fraudulence.
>> More to the point: no one has ever, and I mean
>> ever, reported the date of any rock younger
>> than 700,000 years. As far as I'm concerned,
>> conventional radiometric dating methods would
>> not be able to give a reliable date for the
>> eruption of Mount Vesuvius and the destruction
>> of Pompeii and Herculaneum, did we not have
>> the eyewitness account of Pliny the Younger
>> to go by.
Measuring the age of rocks just a few hundred thousand years old would be sort of like using a yardstick to measure the width of a human hair.
People don't do that. But that is not because yardsticks aren't accurate. Instead it is because they are not that PRECISE.
You really should check out the different definitions of "accuracy" and "precision" some time.
Would a reading of 770,000 plus-or-minus 1 million years mean much to anyone?
That's the problem with all of your examples. They try to measure very, very young rocks with a procedure known ahead of time to have an error of plus-or-minus a million years. Then when the error falls within the expected million years, they cry "foul".
It really is like trying to measure a very small things with a yardstick.
But that doesn't demonstrate that there are errors when calculating the age of rocks that are BILLIONS of years old. A yardstick, properly used, can measure distances of a football field or longer with relatively small error percentages.
>> Disheartened? No. Disappointed, yes. Disappointed
>> that what we call science has now been
>> thoroughly politicized.
Disheartened? No.
Surprised? Not that either.
Creationists ALWAYS engage in fraud in order to make their points.
Your examples provide excellent supporting evidence for those claims.
There is NO evidence supporting a young Earth.
The Earth is 4.5 billion years old.
Deal with it.

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