Validity of Radiometric Dating

Someone with understanding and experience explained it here. I particularly liked the bit where they read the graph backwards.

That's a very reasonable question. I think you want whoever provided you with the answer to your question to back it up with some evidence. So what did you think of the answer given at the link JonF posted in Message 81? I note that you never responded to JonF.I highly recommend starting with the article at the link below.http://www.asa3.org/ASA/education/origins/helium-rw.pdfThe short answer is that the analysis shows that the assumptions used in coming up with accelerated escape of helium are unfounded and refutable using evidence from the original paper. In addition ages obtained from the same zircons using U-Pb give ages inconsistent with the "leaky zircon" dating.Now we can go back and forth about whose analysis is correct, but other evidence makes that kind of dickering unnecessary.Independently from that, there is plenty of evidence that radioactive decay have actually been constant over a relevant time interval. Data form supernova SN1987a indicates that decay rates for radioactive nuclides are the same today as they were hundreds of thousand of years. We also have evidence that the decay energy of some high mass alpha emitters was constant over hundreds of millions of years which leads to the conclusion that the decay rates were also constant.There has been lots of back and forth between scientists and the writers of the original study, and it might be worthwhile to try to form an opinion of who is the winner. But it turns out that there is lots of evidence that the earth, sun, and solar system are billions of years old. One debated study won't change that.

This is a PRATT (point refuted a thousand times) ... Claim CD015:

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Uranium and thorium in zircons produce helium as a by-product of their radioactive decay. This helium seeps out of the the zircons quickly over a wide range of temperatures. If the zircons really are about 1.5 billion years old (the age that conventional dating gives assuming a constant decay rate), almost all of the helium should have dissipated from the zircons long ago. But there is a significant amount of helium still inside the zircons, showing their ages to be 6,000 +/- 2,000 years. Accelerated decay must have produced a billion years worth of helium in that short amount of time.

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Source:

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Humphreys, D. Russell, Steven A. Austin, John R. Baumgardner, and Andrew A. Snelling, 2003. Helium diffusion rates support accelerated nuclear decay. Error | The Institute for Creation Research
Humphreys, D. Russell, Steven A. Austin, John R. Baumgardner and A. A. Snelling, 2004. Helium diffusion age of 6,000 years supports accelerated nuclear decay. Creation Research Society Quarterly 41(1): 1-16. The page you were looking for doesn't exist (404)

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Response:

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1. Subsurface pressure and temperature conditions affect how quickly the helium diffuses out of zircons. D. R. Humphreys et al. selected a rock core sample from the Fenton Hill site, which Los Alamos National Laboratory evaluated in the 1970s for geothermal energy production. The area is within a few kilometers of the Valles Caldera, which has gone through several periods of faulting and volcanism. The rocks of the Fenton Hill core have been fractured, brecciated, and intruded by hydrothermal veins. Excess helium is present in the rocks of the Valles Caldera (Goff and Gardner 1994). The helium may have contaminated the gneiss that Humphreys et al. studied. In short, the entire region has had a very complex thermal history. Based on oil industry experience, it is essentially impossible to make accurate statements about the helium-diffusion history of such a system.
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2. Scientific studies, especially those with radical implications, do not mean much until the results have been replicated by others. Many scientific claims have disappeared entirely when others could not get the same results. Confidence in this particular paper is reduced by certain points:
   • Most measurement errors and variabilities are not reported. Therefore, we do not know how accurate the results are.
   • Humphreys et al. claimed that they studied zircons and biotites from depths of 750 and 1,490 meters in the Jemez Granodiorite. However, Sasada (1989) showed that at those depths, the samples came from a gneiss, an entirely different rock type.
   • Because of math errors, the Q/Q0 values (fraction of helium retained), used by Humphreys et al. to derive their dates, are too high.
   • Humphreys et al. (2003) failed properly to total their data in Appendix C, which means that they grossly underestimated the total amount of helium released by their 750-meter-deep zircons. The amount of helium in the zircons greatly exceeds the amount that would be expected from the radioactive decay of uranium over 1.5 billion years. The high helium concentration may be due to samples that were abnormally high in uranium and/or to the presence of excess helium.
   • Much is made of the fact that samples five and six retained the same amount of helium, even though the amounts are probably at the limit of what could be measured. The possibility of measurement error accounting for the results is never mentioned.
   • If one discounts sample five, which is likely at the limit of measurable precision, the conclusions of Humphreys et al. (2004) rest on just three samples. Such a small data set may be the basis for further research, but not for drawing firm conclusions.
   • Humphreys et al. (2003, note 9) referred to correcting "apparent typographical errors" in the raw data, casting suspicion on the validity of all the data.
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3. The helium results could easily be due to an aberrant sample. They could be an artifact of the experimental or collecting method (e.g., defects in the zircons caused by rapid cooling) or from just plain sloppiness. We cannot know for sure until others have looked at the issue, too.
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4. Producing a billion years of radioactive decay in a "Creation week" or year-long flood would have produced a billion years worth of heat from radioactive decay as well. This would pretty much vaporize the earth. Since the earth apparently has not been vaporized recently, we can be confident that the accelerated decay did not occur. (Humphreys recognizes this "heat problem" but is currently unable to provide a solution.)
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5. If helium concentrations stay high around the rocks, it is possible for helium to diffuse into voids and fractures in the zircons, or at least high helium pressures could reduce the rate at which helium diffuses out. Either of these scenarios would invalidate the helium diffusion calculations in Humphreys et al. (2003, 2004). Helium concentrations within the earth become high enough for commercial mining. The sample measured by Humphreys et al. came from an area that is probably helium enriched. Helium deposits are common in New Mexico, and excess helium has been found just a few miles from where the sample was taken (Goff and Gardner 1994). To test for the presence of excess helium in their zircons, Humphreys et al. should look for 3He.
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6. Uranium does not decay directly to lead; rather, it proceeds through a series of multiple intermediate radioactive elements (Faure 1986, 284-287). It takes about ten half-lives of the longest lived intermediate to achieve secular equilibrium (i.e., each intermediate having the same activity). The uranium decay series contains elements with half-lives well over 10,000 years. If the decay rates changed suddenly, we would not expect the various elements to be in a secular equilibrium. Humphreys et al. should test for this in their zircons. Other uranium ores are at secular equilibrium, indicating a constant decay rate for at least the last two million years.

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Links:

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Henke, Kevin R. 2005. Young-earth creationist helium diffusion "dates": Fallacies based on bad assumptions and questionable data. RATE's Ratty Results: Helium in Zircons

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References:

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1. Faure, G., 1986. Principles of Isotope Geology, 2nd ed. New York: Wiley.
2. Goff, F. and J. N. Gardner, 1994. Evolution of a mineralized geothermal system, Valles Caldera, New Mexico. Economic Geology 89: 1803-1832.
3. Sasada, M., 1989. Fluid inclusion evidence for recent temperature increases at Fenton Hill Hot Dry Rock Test Site west of the Valles Caldera, New Mexico, U.S.A. Journal of Volcanology and Geothermal Research 36: 257-266.

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So if someone wanted to intentionally look for a site that they would know before-hand would produce anomalous results, then this is exactly the kind of formation that they would (dishonestly) use. This type of "study" has been done by dishonest creationists before (McMurdo Sound Seal comes to mind).For instance if I do a google on high helium expected I get a number of results, including:

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Yellowstone thermal features produce unexpectedly high ...
Page not found | Yellowstone Gate

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As the Yellowstone hotspot has warped the earth’s crust, that helium has come floating out. Researchers discovered what they describe as the prodigious degassing ...

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Not surprisingly the Yellowstone hotspot area has the same kind of fractured rock conditions seen at the Fenton Hill site, and I would expect that any Zircons in that area would have higher than normal concentrations.Intentionally providing false information to deceive others is lying, by definition ... and the lie is in the phrase "than expected" not in the physical results.Here is the ICR article: Both Argon and Helium Diffusion Rates Indicate a Young Earth | The Institute for Creation Research It's already been done -- about 10 years ago, and we should not need to reinvent the wheel every time a creationist tries to foist off old debunked poppycock as something "new" ... because that too is dishonest.For some reason creationists seem to have a problem with honestly discarding discredited information (like piltdown man etc).Enjoy.Edited by RAZD, : ...

duplicateEdited by NoNukes, : No reason given.

NoNukes,
Thank you! I really appreciate the professionalism you replied with. I will look into those articles more and get back to you. You did a great job of explaining it. Again, thank you.

I had nice long post composed to explain some of the basics and hit some wrong key and the browser closed. Good thing I have a spare keyboard.This is a discussion board, not a tutorial-on-demand site. Your questions have been answered by people with understanding and experience and you haven't bothered to read them, and you've been given links to those explanations. Why should e\we reinvent the wheel? I have read all the available creationist and mainstream literature on the subject and you've not lifted a finger to read the easily available mainstream explanations.The explanations are long and many, and involve pictures and graphs and (some) equations. It is a significant effort to condense those explanations and maintain accuracy. Why should we make that effort for someone too lazy to click and read a link?Do your homework and then we'll be glad to explain specific questions and issues you may have, and discuss the situation in general.

How can one be sure as to what atomic one is looking at? Are there more useful and powerful radioactivity detection devices which give away the radioactive source?What is to say that noble gas in hard rock is not radioactive?Edited by OS, : No reason given.

You need a lot more knowledge before you will be able to ask meaningful questions.Scientists prepare and analyze the contents of their samples. No noble gas is radioactive under any conditions. It is not possible to identify from what isotope a decay particle came, but it is possible and easy and always done to prepare samples containing a significant amount of only one isotope.

When you use a geiger counter alone, you cannot be sure. That's why methods of that type are not used to do radiometric dating.Something to consider. Each radioactive decay emits a particle of a characteristic type and energy. We can confirm the type of decay by measuring that energy and by looking for the daughter products produced by the decay. For example, Cobalt 60 decays by beta decay. Each decay emits gamma radiation of about 1.3 Mev and a low energy beta particle. The daughter product is a stable isotope of Nickle. One method for analysis is as follows.Instead of simply sticking a Geiger counter next to a bulk sample and learning absolutely nothing useful for determining the age of a sample, we instead use a mass spectrometer to determine the exact composition of isotopes in a sample. There is absolutely no question about what isotopes are being measured.What you are attempting, namely looking for issues in radiometric dating by asking random questions that are unrelated to the processes and methods actually used is unlikely to result in stumbling upon anything of real interest. Might I suggest doing some research into what techniques are actually being used, and then repeating the attempt after having done that?

Very helpful, thanks See NoNukes reply for a helpful post.Edited by mram10, : No reason given.Edited by mram10, : No reason given.

To answer your question directly: a lab could melt a sample and collect the gases that were released. Some of that gas would be argon, most likely. Feeding the gas to a mass spectrometer wouldshow that argon to be the isotopes -36, -38, and -40, all non-radioactive. Any of the other (radioactive) isotopes of argon have short enough half-lives that they would be completely decayed after sitting in a rock for just the 6000 years that Faith would give you since the world formed.One radioactive inert gas you can find in rocks is radon. If there is uranium in the rock, it will decay (very slowly) and continuously supply traces of radon - though the radon itself then decays, finally ending up as lead.

Generally, I think the answers were good, though I tend to think noble gases having lots of neutrons could be more radioactive in the rock, than out of it. But it maybe easily the other elements before transmutation. But thinking about this, I have to conclude you need in the rock what you need in a lab for there to be transmutation of elements.Edited by OS, : No reason given.Edited by OS, : No reason given.

This doesn't make any sense. Do you even know what radioactivity is?

(I am not sure if it is even radiation or light.) It's the activity of the nucleus from which radiation is emitted.Edited by OS, : To state clearly what isn't clear from wiki.

Why don't you put together a post with three or more sentences in it and tell us exactly what your objection is? Between your tendency to express yourself in vague ways and your frequent departures from conventional science, I cannot even guess at what your point is. Maybe you've raised an important issue here, but what is it?