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Author Topic:   Assessing the Radioisotopes and the Age of the Earth (RATE) Project
JonF
Member (Idle past 167 days)
Posts: 6174
Joined: 06-23-2003


(1)
Message 12 of 36 (563682)
06-06-2010 1:52 PM


In fact, it appears that one of the RATE results the YECs have trumpeted widely actually supports the old-earth radiometric dating! The ASA collection of relevant links includes links to several works by Dr. Gary Loechelt, who has applied mainstream diffusion analysis to the RATE work on helium in zircons, and found many errors. His work should be more widely known.
Helium Diffusion in Zircon: Flaws in a Young-Earth Argument, Part 1 (of 2) (non-technical blog post)
Helium Diffusion in Zircon: Evidence Supports an Old Earth, Part 2 (of 2) (non-technical blog post)
Fenton Hill Revisited: The Retention of Helium in Zircons and the Case for Accelerated Nuclear Decay (technical paper)
Helium evidence for a young world continues to confound critics ("response" by Dr. Humphreys)
Helium Diffusion in Zircon: A Response to Questions by the Rate Team (Dr. Loechelt's non-technical response to Dr. Humphreys)
A Response to the RATE Team Regarding Helium Diffusion in Zircon (Dr. Loechelt's more detailed response to Dr. Humphreys)
In adddition, Dr. Loechelt has been discussing his models and RATE at Helium in Zircons?, and has posted several additions and amplifications in that thread..

  
JonF
Member (Idle past 167 days)
Posts: 6174
Joined: 06-23-2003


(1)
Message 14 of 36 (563790)
06-06-2010 8:32 PM
Reply to: Message 13 by BobTHJ
06-06-2010 7:24 PM


The RATE project though does provide SOME evidence for a young-earth. The piece I am the most familiar with is the helium diffusion in zircon prediction - this was a blind study that resulted in an accurate prediction matching a 6,000 year old earth with accelerated decay at or near the beginning of that timespan. Here's a link to a more recent article Dr. Humphreys discussing/rebutting some of the criticisms of this experiment
Note that there's precious little discussion and no rebuttal. See below.
The biggest detractor to this experiment seems to be Dr. Gary H. Loechelt, whose most recent critical review of this experiment (that I could find) is here. Reading through Dr. Loechelt's response it appears he validly shows how the RATE experiment results could be off - but the percentage is miniscule. From my understanding we're talking 30% of the surface helium (which is 1-2%) remaining - so the results may be off by less than 1/2 a percent - well within tolerable error limits, and nowhere near the hundred thousand orders of magnitude required for the data to fit an old-earth model. I admit I'm not following the second half of his article very well - so perhaps I'm missing something.
Sorry, you're missing something. Dr. Loecholt demonstrated that correct use of mainstream diffusion theory, the real temperature history of Fenton Hill, and the RATE group's data, that the inescapable conclusion is an old Earth. See section 3.5 and 4 of the technical paper listed above. See also the thread linked to above, where he derives the same conclusion from data published by Reiners in 2005.
In addition, in re Humphreys' "rebuttal", I've checked the primary sources and there's no question that Humphreys (or whoever actually did it) read the temperature graphs in his references backward. Humphreys thinks that Fenton Hill was hotter in the immediate past than it is today, whereas it really was cooler. If anything Dr. Loechelt understated the case for Humphreys' making an error. I'm astonished, and I don't have a high opinion of YECs to start with. Incredibly enough this blunder doesn't affect Humphreys' analysis, but it does highlight the amateurish nature of the RATE project and the inadequacy (to say the least) of the "peer review".
The major issue is whether one extrapolates the volume diffusion line to the temperatures of interest (as Loechelt does) or extrapolates the defect diffusion line to the temperatures of interest. Loechelt makes a good case based on references to noble gas diffusion studies from the 1960s up to 2005. Humphreys makes no case at all, he just assumes his method is correct.
Is the RATE project's conclusion of accelerated decay a reasonable one?
Not a chance. See, for example, the thread linked to above. I'm somewhat proud of digging up the dose data showing that the proposed accelerated decay would have killed Noah and the gang from radiation poisoning from the 40K in their bodies. And another poster pointed out that the uranium decay series would not be in secular equilibriium anywhere, which it is in many places. The list of show-stopping problems with accelerated decay is virtually endless. See, for example, The Constancy of Constants and The Constancy of Constants, Part 2.

This message is a reply to:
 Message 13 by BobTHJ, posted 06-06-2010 7:24 PM BobTHJ has replied

Replies to this message:
 Message 16 by BobTHJ, posted 06-08-2010 9:44 PM JonF has not replied

  
JonF
Member (Idle past 167 days)
Posts: 6174
Joined: 06-23-2003


Message 15 of 36 (563802)
06-06-2010 9:24 PM


Science moves on ...
I can't resist posting an abstract that Dr. Loecholt posted a few hours ago:
quote:
Zircon (U—Th)/He thermochronometry in the KTB drill hole, Germany, and its implications for bulk He diffusion kinetics in zircon
Melissa R. Wolfe ⁎, Daniel F. Stockli
Earth and Planetary Science Letters 295 (2010) 69—82
This study presents new down-hole zircon (U—Th)/He (ZrHe) ages, laboratory He diffusion measurements, and numerical thermal modeling of ZrHe ages from the Continental Deep Drilling Project (KTB) in Germany to investigate He diffusion kinetics in zircon in nature over geologic timescales and to test the applicability of laboratory-derived He diffusion kinetics. Single grain laser (U—Th)/He ages, calculated using standard alpha ejection correction procedures assuming homogenous parent-nuclide distribution, display a systematic decrease in ZrHe ages from ∼112 to b1 Ma with increasing depth. Down-hole ZrHe results display consistent ages of ∼8515 Ma down to ∼4.7 km, in agreement with rapid Cretaceous cooling documented by previous thermochronometric studies from the KTB drill hole. Below ∼5 km, ZrHe ages systematically decrease in age and are completely reset (b1 Ma) below ∼7.2 km. The temperature range (∼130—200 C) in which ZrHe ages systematically decrease defines a well-behaved zircon helium partial retention zone (HePRZ). In addition, this study presents new, cycled step-heating experiments on zircon samples from the KTB drill hole. Results from these new KTB zircon diffusion experiments indicate an activation energy (Ea) of 160 kJ/mol and a frequency factory (Do) of 0.03 cm2 s−1 with an estimated closure temperature (Tc) of 181 C, which are in excellent agreement with published He diffusion kinetics for zircon. To compare the ZrHe results and bulk diffusion kinetics, we modeled diffusion parameters using the well-established thermal history of the KTB drill hole. The computed zircon HePRZ for the KTB drill hole is consistent with observed down-hole ZrHe ages and published and KTB-specific laboratory-derived He diffusion kinetics. Our results from ZrHe analysis from the KTB drill hole suggest that He diffusion of zircon in nature may not be controlled by anisotropic diffusion behavior, but rather behaves in accordance with laboratory-derived diffusion kinetics. The observed ZrHe ages from the KTB drill hole are in excellent agreement with predicted ZrHe age data and underscore the validity and applicability of ZrHe dating as a reliable thermochronometer.
{emphasis added}
The last bolded piece means extrapolating the volume diffusion line, as Loecholt does and Humphreys doesn't.
There's been no new RATE research on helium diffusion in zircons since 2005, the second RATE book, and most of the work was done before 2003. Meanwhile there's an explosion of real scientific studies of helium diffusion in zircons and dating samples using that.
Any bets on whether the RATE group will ever produce anything new on this subject? Or was their only purpose to provide sciency-sounding justification for their religious beliefs, and they've acheived their purpose?

  
JonF
Member (Idle past 167 days)
Posts: 6174
Joined: 06-23-2003


Message 22 of 36 (564930)
06-13-2010 7:45 PM


Why has Carbon 14 decayed at the same rate? Because that's what it does now.
Nope. Standard creationist error; you don't know the evidence for constant radioactive decay, so you assume that there is none.. See Message 13.

Replies to this message:
 Message 23 by Coyote, posted 06-13-2010 7:49 PM JonF has not replied

  
JonF
Member (Idle past 167 days)
Posts: 6174
Joined: 06-23-2003


Message 29 of 36 (565122)
06-14-2010 9:02 PM
Reply to: Message 26 by Jzyehoshua
06-14-2010 6:33 PM


Re: Another gross mistake
have brought up this same reservation dozens of times on similar forums before, and have yet to receive a solid answer on the subject of why half-lives can't decay faster.
I don't believe you. This sort of information is widely known.
Probably the best evidence is that we're here. Were decay rates increased enough to make a 10,000 year old earth possible, the earth would still be molten. Oh, I suppose God could magic the heat away. But then all life would be killed by radiation. Oh, I suppose God could magic the radiation away. But then so many astronomical observations would have to be adjusted. Oh, I suppose God could magically adjust the stars and galaxies. But then the Oklo reactor wouldn't have operated (the moderating water would have boiled away too fast, and many other problems). Oh, I suppose God could have magicked the Oklo reactor. But then all that we know about nuclear physics is wrong *and we know a lot. Oh, I suppose God could magically adjust the fundamentals of the Universe.
After a while the number of ad-hoc miracles get to be too much for any rational person. Here's a couple of pointers to some information on some ore of the things God would have to magic away:
The Constancy of Constants
The Constancy of Constants, Part 2
And there's some moderately technical discussion of more evidence that falsifies AND (Accelerated Nuclear Decay) interspersed with discussion of the RATE results on zircons, at Helium in Zircons?.

This message is a reply to:
 Message 26 by Jzyehoshua, posted 06-14-2010 6:33 PM Jzyehoshua has not replied

  
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