Monday, February 8, 2010

Helium diffusion and the age of the earth


For those of you who normally follow my blog, you may have noticed we have some new visitors among us. I made a comment on Ray Comfort’s blog, Atheist Central, today and many of my new friends found me there and came over for a visit. I hope you’ll join me in welcoming them. They’ve given me an opportunity to put into practice 1 Peter 3:15.

“But sanctify the Lord God in your hearts, and always be ready to give a defense to everyone who asks you a reason for the hope that is in you, with meekness and fear.”

To God be the glory! Now, back to helium diffusion.

I want to encourage those of you who are interested in a more thorough discussion of Helium diffusion and its implications for the age of the earth to read Radioisotopes and the Age of the Earth volume I pp. 344-351 and volume II pp. 25-95. I am not a geochemist or geophysicist so I’ll be highlighting the main findings of this study. You know where to go for more details.

There are a couple of things we need to understand before the results of this study will mean anything to us.

1. Helium is a byproduct of the radioactive decay of U238 to Pb206. For every one U238 that decays to Pb206, 8 He atoms are emitted.

2. Helium is a lightweight gas that diffuses readily through solids. In fact, helium leakage is fast enough that it is often used to test laboratory vacuum systems. Because of the relatively fast rate of He diffusion, it would not be expected to be found in significant quantities in rocks of the earth’s crust, if the earth is billions of years old. Even if the earth were only a million years old, He wouldn’t be expected to exist to a great degree in rocks of the earth’s crust.

So, we know the ratio of helium atoms emitted per U-Pb parent-daughter couple and we know that helium diffuses rapidly through solids. This information combines to suggest that a high content of helium still trapped within rock under the surface of the earth supports the theory of a young earth.

The first part of this study actually took place 25 years ago when scientists recovered zircons (crystals found in granite) from deep bore holes in a biotite formation embedded in hot Precambrian basement granite rock estimated to be 1.5 billion years old using Pb-Pb radioisotope dating. Exciting finding number 1 was that they found He, lots more than would have been expected had it indeed had 1.5 billion years to diffuse.

1. High percentage of He retention supports the theory of a young earth. It was especially surprising since these zircons were microscopic (smaller diffusion distance) and obtained from a very hot, volcanic area (heat increases diffusion rates).

So, the zircons came from rock estimated to be 1.5 billion years old. Given this age, evolutionary scientists would expect most of the He to have escaped the small zircons by diffusion. This result suggests that 1.5 billions years worth of decay occurred over a much shorter period of time. One or more episodes of accelerated nuclear decay could explain this finding.

The recent part of the study consisted in coming up with a mathematical model that would fit the zircon data discussed above. An evolutionary model of constant decay did not fit the data, so the creation scientists wanted to establish a model that would fit the data and help to more accurately estimate the age of the zircons and the rock sample they were obtained from. This leads us to exciting finding number 2.

2. Using the rate of He diffusion to estimate the age of the earth, an age of 6,000 years +/- 2,000 years was obtained. So, Pb-Pb radioisotope dating estimates the sample at 1.5 billion years, but that age is inconsistent with the vast amounts of He still trapped within the zircons. And the He diffusion rate dating estimates the earth is 6,000 years old, but doesn’t explain the amount of Pb-Pb decay required to emit that much He. So, I reiterate, it appears that 1.5 billions of years worth of radioactive decay occurred over a period of 6,000 years. This reinforces the creation scientist’s hypothesis of one or more periods of accelerated decay having occurred in the past, most likely during creation week and the flood.

I touched on this last time, but many of my visiting friends still insist that the excess energy release (yes, of cataclysmic proportions) is a stumbling block for accelerated decay. I know I don’t need to remind them of this, but the massive energy release for a 6 day creation already gives us this problem. So, again this is familiar territory for a creation scientist. However, rapid expansion of the cosmos (“stretching out the heavens” which occurs in 17 verses of the Bible) could dissipate this heat. There is also some evidence that rapid cooling coincided with periods of accelerated decay. For instance, the data in the He diffusion study “imply that after the zircons acquired their He, they were never very much hotter than they are now, nor were they hot for very long… In other words, our data and model are consistent with at most a short, moderate pulse of heating during and just after the accelerated decay episode.” (Radioisotopes and the Age of the Earth vol. II pp. 68-69) I’ll address another line of evidence for accelerated decay accompanied by rapid cooling in my next post, so stay tuned.

19 comments:

  1. Oh wow, it really is starting to get technical now isn't it. My sleep-starved brain has trouble processing all that information. But how great that the Creation scientists found that through their model the helium diffusion rate was consistent with a young earth. I love reading about that.

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  2. Again from from Perspectives on Science and Christian Faith, March 2008, pages 35-39 published by American Scientific Affiliation : A Fellowship of Christians in Science on the results of RATE.

    "The RATE team has honestly acknowledged that even if their technical claims were accurate, there remain unsolved problems that cannot be reconciled with any known scientific process. In his summary at the RATE conference in Denver on Sept. 15, 2007, Don DeYoung noted the need to invoke divine intervention in order to circumvent these problems. However, the oft-stated summary by the RATE team, that their results provide assurance of the biblical interpretation of a young earth, leaves the average listener with the mistaken impression that these problems are nonexistent, trivial, or soon to be resolved. Rather, the RATE team acknowledged overwhelming evidence for hundreds of millions of year’s worth of radioactivity and admitted that compressing this activity into a few thousand years would generate more than enough heat to vaporize all granitic rock. They state that no known thermodynamic process could dissipate such a large amount of heat Their expressed hope in solving heat dissipation by cooling via enhanced cosmological expansion has not been realized and is not consistent with our knowledge of the expanding universe. Thus, the RATE team has provided solid evidence that, scientifically, the earth cannot be thousands but must be billions of years old."

    You are, quite literally hand waving away a massive issue they acknowledge with their own results.

    That assuming their results are to be considered accurate.

    You can read the whole RATE dialogue with the American Scientific Affiliation : A Fellowship of Christians in Science, it's online for all to read, including a rebuttal from RATE. http://www.asa3.org/ASA/education/origins/rate-pscf.htm

    And of course there is a secular dismantling of the project.

    http://www.talkorigins.org/faqs/helium/zircons.html
    Very long someone else might like to summarize, I wouldn't know where to begin.

    I will also make this note. If you want to invoke variable/changing decay rates then you invalidate any sort of fine tuning argument later on.

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  3. "So, I reiterate, it appears that 1.5 billions of years worth of radioactive decay occurred over a period of 6,000 years. This reinforces the creation scientist’s hypothesis of one or more periods of accelerated decay having occurred in the past, most likely during creation week and the flood."

    What is the mechanism you propose for an acellerated decay rate that violates the laws of physics?

    "it appears that 1.5 billions of years worth of radioactive decay occurred over a period of 6,000 years." No, it does not. That is called shoehorning. You are essentially trying to make the argument that because the decay rate of He shows the earth to be billions of years old, it proves that the earth is only six thousand years old?

    That is fractured logic and a non-sequitur.

    You are starting with a supposition that the earth is six thousand years old, which of course is easily proven wrong.

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  4. What you have done here is analagous to this:

    I'm sitting in my house and hear thumping noises all alound on the outside walls. It goes on for several minutes and I finally go outside to see what's going on. I discover over a hundred aggs have been thrown at my house and are dripping every where.
    I look over nd see you standing there with a big basket with three egss in it. You hav eggshells stuck in your hair and yolk stains all over you, broken eggs at your feet.

    I say, "You egged my house!"
    You say, "No the fact that there are eggs stuck to your house and I have eggshells in my hair reinforces that it could not have been me that did it."

    To even begin to use the He decay argument, you must have the ohysical evidence of how it could be any different than what we observe, just as you would have to have some evidence, other than you didn't do it, to prove you didn't egg my house.

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  5. Bathtub and Froggie,

    You are very quick to point out criticism of the creation model, but the He diffusion data does fit the model. So, what you have to do, is explain why the He had not diffused out of the zircons if it had 1.5 billion years to do so.

    Froggie- we're not talking about He decay, but diffusion. The physical evidence is the undiffused He still trapped within the microscopic zircons.

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  6. Helium trapped in rock strata is under pressure

    Diffusion rates on the planet's surface are going to be remarkably higher than rates found under hundreds or thousands of feet of rock. The RATE study extrapolated from HE diffusion in a vacuum, not under pressure.

    "researchers have already shown that the diffusion of noble gases in silicate minerals may decrease by at least 3-6 orders of magnitude at a given temperature if the studies are performed under pressure rather than in a vacuum."

    REF: McDougall, I. and T. M. Harrison, 1999, Geochronology and Thermochronology by the 40Ar/39Ar Method, Oxford University Press, New York.

    REF: Van Allen, J.A. and F. Bagenal, 1999, "Planetary Magnetospheres and the Interplanetary Medium," in J. K. Beatty, C.C. Petersen, and A. Chaikin (eds.) The New Solar System, 4th ed., Cambridge University Press, Cambridge, United Kingdom.

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  7. Yeah, it's funny how that study can't be replicated consistently in the laboratory.

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  8. From Reasons to Believe.

    http://www.reasons.org/helium-diffusion-zircon-flaws-young-earth-argument-part-1-2

    "The helium diffusion clock used by the RATE team was actually a complex mathematical model describing the process of helium diffusion from zircon crystals. One may legitimately ask, “How well did they read their diffusion clock?” After following their research for many years, I conclude that they read this clock poorly. The RATE study contained at least five specific flaws in the data analysis and modeling that were serious enough to invalidate their conclusions. Let’s focus on the two biggest errors."

    "First, the RATE model used a constant temperature over time. Several lines of geologic evidence indicate that the thermal history of Fenton Hill has been anything but uniform. Recent (geologically speaking) volcanic activity has raised the ground temperature at the site to over twice the typical value across the continent. These elevated temperatures have been sustained for a relatively short period of time on a geologic timescale. Therefore, the use of a constant temperature by the RATE team demonstrates a misunderstanding of the thermal history of the site."

    "The second error committed by the RATE research team was more subtle. The modeling of the helium diffusion clock required an underlying model for the helium diffusion kinetics (i.e. the manner in which temperature affects the motion of atoms). Using data from a laboratory experiment in which gas released from a zircon sample was measured at different temperatures, they extracted the parameters for a simple kinetic model. The problem with this model is that it treated all helium atoms the same, regardless of whether they were in the bulk crystal or near a defect. Most helium atoms will lie in portions of the undisturbed crystal, whereas only a small fraction will lie in the vicinity of a defect. At low temperatures, the small fraction of atoms near a defect will be mobile, whereas the vast majority of atoms will only begin to move at higher temperatures"

    There's more of course, the point is once again Scientist Christian's debunk this work.

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  9. In response to criticism of RATE's use of constant Temp:

    They cover this on pp. 52 and 61 of vol. II. The gist of it is that there is evidence (as one of you pointed out) of volcanic activity "and have past temperatures being higher, 110-190 degrees C higher than today's levels. This would put the samples well into the high-slope 'intrinsic' range of diffusion." Meaning- according to your dating, there would still have been millions of years at a high enough temp for diffusion coefficients to be 2-3 orders of magnitude above today's values...This makes our assumption of constant temperatures at today's values quite favorable to the uniformitarian scenario." p.52

    In response to criticism of RATE's model being performed in a vacuum: Here is Dr. Humphrey's explanation of why this doesn't influence the outcome. http://www.trueorigin.org/helium02.asp An exerpt from his explanation is as follows:

    "...vacuum measurements are standard procedure for all zircon diffusion researchers. None of them have considered pressure an important enough variable to include in their experiments. Henke does not seem to have asked himself why the experts have done so. The answer, as I will show below, is that these pressures aren't important for zircons...Zircon, being harder than steel, would be much less compressible than lead.[5] So pressure should affect diffusion rates much less than in lead, which for kilobar pressures had a reduction of only 20% in the rates, according to the paper above."

    In response to the allegation that no one has been able to replicate these results: Below is another study also on He diffusion in zircons which obtained similar results.

    P. W. Reiners, K. A. Farley, and H. J. Hickes, "He diffusion and (U-Th)/He thermochronometry of zircon: Initial results from Fish Canyon Tuff and Gold Butte, Nevada," Tectonophysics 349(1-4):297-308, 2002.

    Summary of Humphrey's defense: The diffusion rates are nearly 100,000 times higher than the maximum rates the "Evolution" model could allow. That leaves no hope for the 1.5 billion years. For most of that alleged time, the zircons would have to have been as cold as liquid nitrogen (196ºC below zero) to retain the observed amount of helium. Such a "cryogenic Earth" model would not help uniformitarians, because it would violate uniformitarianism!

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  10. "In response to the allegation that no one has been able to replicate these results: Below is another study also on He diffusion in zircons which obtained similar results."

    I didn't say no one could replicate the results. I said the results are inconsistent meaning the amount of He diffusion is dependent upon rock formation and pressure. Misidentified zircons could produce effects similar to Humphrey's results, which is exactly what happened. They mistook gneisses for granodiorites.

    For example, this study gives very different results than Humphrey's work.

    Magomedov, Sh. A., 1970, "Migration of Radiogenic Products in Zircon," Geokhimiya, v. 2, p. 263-267 (in Russian). English abstract: Geochemistry International, v. 7, n. 1, p. 203.

    "P. W. Reiners, K. A. Farley, and H. J. Hickes, "He diffusion and (U-Th)/He thermochronometry of zircon: Initial results from Fish Canyon Tuff and Gold Butte, Nevada," Tectonophysics 349(1-4):297-308, 2002."

    Unfortunately, this paper requires a fee to download, so I'm in no position to properly critique the results. However, from the extract and index, nothing appears anomalous about the amount of He diffusion they recorded. They would have mentioned something if they found more He than they were expecting.

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  11. My brain is spinning from trying to read and understand all the comments here. It seems that whether you take the view of Special Creation or the view of Evolution you need to have faith that what you believe is true. People who believe in the Theory of Evolution have to just as much faith in their "model" as those who believe in 6 Day Creation. The problem, as I see it, is in the central focus. I choose to believe that God created me and gave the Bible as His word, so my focus is on seeking evidence to support Creation. People who choose to believe that their existence was a {very, extremely} random chance, and that they don't need to acknowledge God, focus on proving that evolution is true. The part I love is this - as a Christian I don't need scientific proof to believe Creation. I know it's true in my heart. And I know that, one day, everyone will know that it is true. Evloutionists, however, must continue to try and prove their theory - their belief system ... their faith - not only to the world but to themselves.

    Bless you for (1) being able to understand all this scientific stuff,(2) explaining it to those (me) who find it difficult to understand, and (3)faithfully persisting in finding the evidence that exists to support Creation.

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  12. "People who believe in the Theory of Evolution have to just as much faith in their "model" as those who believe in 6 Day Creation."

    No, you just need to understand a little science. Ignoring science and then claiming it is too hard to understand so you have to have faith is lazy. Evolution is based on a convergence of evidence. Multiple lines of different biology specializations all point to the same thing. The age of the Earth, is also based on multiple lines of evidence. Different dating techniques all point to the same age. It is not perfect, but neither is most evidence that goes into convicting a criminal. Just like a court case, multiple lines of evidence are taken and then different people in different labs see where they point. It is about convergence of evidence. Also, like a court case, it is not about doubt but reasonable doubt. The only difference between Evolution, the age of the Earth and a normal court case is the amount of evidence. There is more evidence for Evolution and the age of the Earth than for any court case.

    I am blessed! I have a question for you. What, to you, is the best evidence for Young Earth Creationism?

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  13. Stay tuned, Beamstalk, After posting on radioisotope dating, which has long been the friend of evolution and enemy of creation science, I'll post on other "clocks". I chose the most controversial for the young earth creationist to begin with.

    Also, I do agree with Mum-me that both theories require some degree of faith, however I'm grateful that God does not ask us to have a blind faith. We can look around and see the testimony of God.

    However, though I believe there is good evidence for a young earth and my position is that of young earth creationism, should the earth be absolutely proven beyond a shadow of a doubt to be old, my faith would still be unshaken. I think it's possible due to an application of Einstein's principle Relativity that God could have created the world in 6 literal days, but that much more time elapsed on earth. Again, I don't believe this is the case, but Biblically and scientifically it's within the realm of possibility. So, if I'm right about a young earth, your system crashes to the ground with no basis of support. If you're right, mine remains unshaken. So I completely understand how vehemently you're fighting for this. It means everything to the evolutionary model. I don't mind debating, in fact it's given me a chance to read a bunch of arguments and rebuttals that I probably wouldn't have otherwise. Thanks for that. I need accountability to keep on studying. I'm praying specifically for you guys that God will use this to soften your hearts toward Him.

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  14. I don't believe this is the case, but Biblically and scientifically it's within the realm of possibility.

    It's funny how mainstream peer-reviewed journals disagree with you and never print articles espousing a young earth creationist perpestive. I wonder why...

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  15. That is a dodge. I asked what you feel is the best evidence for Young Earth Creationism.

    "So, if I'm right about a young earth, your system crashes to the ground with no basis of support."

    Actually whoever proved that would win a Nobel prize. They would also have to put forth a new model of the Earth and Universe and explain why the old model worked so well, much like Einstein did with Newtonian gravity. Turning over old theories is a sure fire way to become in famous in the science community.

    I am not sure you quite understand the scope of what you are attempting (I also don't think you understand relativity but that is another thing altogether). You are suggesting that science itself is fundamentally flawed. I am not saying it perfect, but it is the best tool we have for determining the truth. If it is as flawed as you are claiming then we would need to reevaluate all our advances.

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  16. Beamstalk,

    I love science and am not suggesting it is fundamentally flawed. Pure science is about discovery and truth. What I've learned, yes first hand, is that EVERYONE has a vested interest in science, at least that's been my observation. No one is above bias. You have yours and I have mine and so does every scientist. How do scientists make a living? They can't just research whatever they're interested in, they have to have NIH funding and a body of literature to support what they want to investigate to even hope for a big grant. I would love to see more scientists like Dr. Art Robinson of the Oregon Institute of Science and Medicine fund their own research. I was very disillusioned by this in academia. Even within cancer research each lab wants, no "needs" to prove themselves right, more than they seem to need the truth. I think everyone starts out just wanting to cure cancer, but then you have to make a living and it turns into a competition about which labs are right and which ones are wrong. Which labs will get the grants and patents and which ones will be left behind. In contrast to this, pure science is the search for the truth. I love this version of science. There have been many who have violated it on both sides of the fence, which is why we have to look critically at the evidence for a young versus an old earth.

    As for what I feel is the best evidence, I asked you to hang on because I have a purpose for the order in which I'm writing these posts. Thank you for allowing me to do that.

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  17. Yeah like how Dr. Andrew Snelling does real geology Monday to Friday to sell to corporations & mainstream folk and and then on Sundays he does YEC geology to sell to churchfolk.

    Google "Will the Real Dr Snelling Please
    Stand Up?"

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  18. I get it now! The reason why evolution is so widely accepted in scientific circles is because there is a giant conspiracy of self-interested scientists. All the 99%+ biologists who espouse a evolutionary viewpoint are in on it. It all makes sense now.

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I'm an on-the-run mom to 6 kids who studied and taught exercise science in a previous life. I love all things running, nutrition, and health-related. I usually run at zero dark thirty in the morning and am often quite hungry before, during, and after my run, but I live a rich, full, blessed life with my children, family, and friends. My faith in God is my anchor, and looking to Him and His promises allows me to live fully even when life circumstances are difficult. While running gives me an appetite, my desire is to hunger and thirst for righteousness more than for physical food.