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Old 05-25-2010, 05:33 AM   #942316  /  #1
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Default Helium in Zircons? (Continuation of "Why Do You Think the Earth is 4Byr old")

Quote:
Originally Posted by JonF View Post
It might be possible to model the Fenton Hill zircons with reasonable accuracy with a single-domain model, because there's so little "loosely bound" helium. I don't know. But it's certainly impossible to model the Fenton Hill zircons with a single-domain model based on measurements of helium outgassing from two domains in comparable quantities because the "loosely bound" helium skews the calculation of the model parameters, and skews them a lot. Loechelt has demonstrated that Humphreys did exactly that. Humphreys has not made any substantive response.
JonF has a good point here, namely that a properly extracted single-domain diffusion model should work. That is what Reiners was referring to when he said

Quote:
Although such modeling does not prove such a mechanism for these non-Arrhenius effects, it suggests that only a small proportion of gas resides in domains that exhibit anomalously high diffusivity, and therefore this phenomenon may not significantly affect the bulk closure temperature or He diffusion properties of most natural zircons.
The statement about not significantly affecting the bulk closure temperature or He diffusion properties of most natural zircons means that the effect can be neglected under most circumstances.

Where did the RATE study go wrong? The key is that if you are going to approximate a multi-domain diffusion system by a more simple single-domain model, you have to focus on the high-temperature part of the Arrhenius curve. In the RATE study, they incorrectly focused on the low-temperature part of the Arrhenius curve. (See for instance Humphreys, D.R., 2005a. Young helium diffusion age of zircons supports accelerated nuclear decay. In Vardiman et al. (2005), Chapter 2, pp. 41-45.) The justification for extrapolating from the high-temperature part of the Arrhenius down to the temperature of interest can be found in the seminal work by Fechtig and Kalbitzer

Quote:
... it is, therefore, allowed to extrapolate the straightline which represents the volume diffusion down to the temperatures investigators are most interested in. (Fechtig, H., Kalbitzer, S., 1966. The diffusion of argon in potassium-bearing solids. In Potassium Argon Dating, Schaeffer, O.A., Zähringer, J. (Ed.), Springer-Verlag, New York, p. 101.)
This insight opens up an entirely new possibility to our discussion. We can avoid the issue Humphreys has with Loechelt altogether by repeating the Fenton Hill analysis using diffusion data from another source, such as Reiners (2004). A single-domain diffusion model should be adequate as long as the kinetic parameters are extracted from the high-temperature part of the Arrhenius curve. For starters, let's compare the diffusion data between Humphreys (2004) and Reiners (2004).

Click image for larger version

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In addition to the Arrhenius curve given by the average activation energy and diffusion prefactor, I have also plotted the Arrhenius curve extracted from sample 01CS15z 66 um (Wallowa Mountains). This particular sample happened to have the best match to the Fenton Hill data. Note that in their experiments, Reiners et al. never took their samples below 300 C. (The line on the graph is just an exponential fit to the data. To see the actual temperature steps, refer to table 1 of their paper.) I would like to know why Humphreys and his RATE colleagues insisted on having diffusion data at lower temperatures when his own experts never did so in their own publications.

In any event, the diffusion simulations can be repeated for the Fenton Hill zircons using the kinetic data from Reiners (2004) and the same geomety, boundary conditions, and thermal history. The results are shown below.

Click image for larger version

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The Humphreys (2004) data were calculated using a multi-domain diffusion model based upon the RATE diffusion experiment, and the Reiners (2004) data were calculated using a single-domain diffusion model based upon the literature. Note that the diffusion simulations are robust in the sense that small changes in the diffusion kinetics do not drastically affect the outcome. The bottom line is that good agreement to the measured helium retention of Gentry is obtained for both experimental sources for the diffusion parameters, provided that the high-temperature data is used to extract the single-domain diffusion model. If one insists that the low-temperature data be included, as Humphreys did, then a multi-domain diffusion model must be used instead.

Let's now consider the implications of these results on Dave Hawkins' argument. His stand is that regardless of the other errors found in Humphrey's work, my work must be rejected because of this statement by Humphreys.

Quote:
Loechelt is right in claim (A), but wrong in claim (B). He overlooked part of one of his own quotes, in which an expert pointed out that loose helium would only affect the initial steps of the laboratory measurement, because after the initial steps the loose helium would be gone. That is one reason diffusion experts recommend ignoring the initial steps. Our experimenter recommended that, and that is exactly what we did. Thus he felt free to tell us that the rates he measured were accurate depictions of the leakiness for the other 98% of the helium. Ironically, our expert is one of those that Loechelt cites in his section about this issue. Loechelt either completely misunderstood the experts, or he deliberately distorted their meaning.
Regardless of whether one considers this statement by Humphreys to be right or wrong, this latest result renders it completely irrelevant. Humphreys cannot make any claim regarding my inappropriate use of a multi-domain diffusion model, because I have replicated the results of my original old-earth model with a simpler single-domain diffusion model. This model relies on the high-temperature steps of a diffusion experiment, and therefore makes no claims about the retention of loosely bound helium. Furthermore, regardless of what Humphreys' expert told him about the interpretation of his own experiment, that too is irrelevant, because I have now abandoned his work for a better dataset published in a credible academic journal by one of his own experts. And since Humphreys is no expert in the field of thermochronometry, he has no grounds to claim that I misinterpreted another persons work. I merely read the paper and used its results in my calculations. Humphreys objections are therefore rendered irrelevant. Are there any counter-arguments to this case? Dave, what are you thoughts?
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Old 05-25-2010, 05:41 AM   #942322  /  #2
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Run davey run!

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Old 05-25-2010, 05:49 AM   #942324  /  #3
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Quote:
Originally Posted by Dave Hawkins View Post
It appears that he read a really screwy graph backwards, but doing so appears to have had no impact on the study at all. It appears to me that Loechelt is interested in a much longer time period that what that graph covers. Loechelt talks about 1 billion years and I think that graph only went back 1 million IIRC.
It is not true that this mistake had no impact at all. Humphreys used it as the basis to determine the constant temperature in his uniformitarian model, which he extrapolated back 1.5 billion years. So essentially, he took the maximum temperature in a graph that covered a million years, and extended it by a factor of 1000X over a billion years without supplementing it with any data from that time period. In my model, I only use data over the time period of its validity. I think that is the better approach. Do you disagree?
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Old 05-25-2010, 07:03 AM   #942337  /  #4
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New thread on Evolution Gives You Tooth Decay starting in

3


2


1 . . .
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It's really nice to read something that actually explains some of this stuff in plain English. As opposed to the Reverse Swahili Pig Latin used by most scientists.
(2014) D. Hawkins BSc, Elec. Eng. (Cum Laude) U. Texas Arlington.
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Old 05-25-2010, 08:51 AM   #942344  /  #5
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In honour of all honest helium-diffusers, I am now going to obtain two handsome working ferrets, and call them "Fechtig" and "Kalbitzer". They will be royally treated their whole lives long.
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Old 05-25-2010, 10:05 AM   #942353  /  #6
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Quote:
Originally Posted by Dave Hawkins View Post
It appears that he read a really screwy graph backwards, ....
a really screwy graph? On what basis is the graph really screwy?
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Old 05-25-2010, 11:05 AM   #942375  /  #7
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Thank you Dr. Loechelt.
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Old 05-25-2010, 11:13 AM   #942377  /  #8
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Quote:
Originally Posted by Dave Hawkins View Post
It appears that he read a really screwy graph backwards, but doing so appears to have had no impact on the study at all.
Because we all know that Water electrolysis pulls H2 and O2 out of the air...
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Old 05-25-2010, 11:51 AM   #942388  /  #9
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I love this latest turn of events. Dave blaming the graph. That's a new one. I wonder when he will get round to doing that with 14C graphs.

"that screwy straight line graph"
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Old 05-25-2010, 01:02 PM   #942417  /  #10
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Welcome Dr. Loechelt. Very fine summary.

Oh, and I enjoyed reading your papers.
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Old 05-25-2010, 01:07 PM   #942419  /  #11
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Quote:
Originally Posted by Dave Hawkins View Post
It appears that he read a really screwy graph backwards, but doing so appears to have had no impact on the study at all. It appears to me that Loechelt is interested in a much longer time period that what that graph covers. Loechelt talks about 1 billion years and I think that graph only went back 1 million IIRC.
So, now we understand that Humphreys read the temperature graph backwards, and remembering that we have Dr. Loechelt directly contributing to the discussion.

Would you then agree that Humphreys use of his "fixed" temperature for diffusion was too high for the past 800 million years?

< also remember that the model for build-up of the He in the Zircons is only over the last 800 million years. before that the temperature was higher and the zircons were "open" and no He retention was implied so we can ignore the first 700+million years of activity on the Fenton Hill site >
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Old 05-25-2010, 01:59 PM   #942464  /  #12
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Quote:
Originally Posted by Jet Black View Post
Quote:
Originally Posted by Dave Hawkins View Post
It appears that he read a really screwy graph backwards, ....
a really screwy graph? On what basis is the graph really screwy?
Some people couldn't figure it out.

Most people did, but some people couldn't.
Or wouldn't.
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Old 05-25-2010, 02:51 PM   #942533  /  #13
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Quote:
Originally Posted by Loechelt View Post
Quote:
Originally Posted by JonF View Post
It might be possible to model the Fenton Hill zircons with reasonable accuracy with a single-domain model, because there's so little "loosely bound" helium. I don't know. But it's certainly impossible to model the Fenton Hill zircons with a single-domain model based on measurements of helium outgassing from two domains in comparable quantities because the "loosely bound" helium skews the calculation of the model parameters, and skews them a lot. Loechelt has demonstrated that Humphreys did exactly that. Humphreys has not made any substantive response.
JonF has a good point here, namely that a properly extracted single-domain diffusion model should work. That is what Reiners was referring to when he said

Quote:
Although such modeling does not prove such a mechanism for these non-Arrhenius effects, it suggests that only a small proportion of gas resides in domains that exhibit anomalously high diffusivity, and therefore this phenomenon may not significantly affect the bulk closure temperature or He diffusion properties of most natural zircons.
The statement about not significantly affecting the bulk closure temperature or He diffusion properties of most natural zircons means that the effect can be neglected under most circumstances.

Where did the RATE study go wrong? The key is that if you are going to approximate a multi-domain diffusion system by a more simple single-domain model, you have to focus on the high-temperature part of the Arrhenius curve. In the RATE study, they incorrectly focused on the low-temperature part of the Arrhenius curve. (See for instance Humphreys, D.R., 2005a. Young helium diffusion age of zircons supports accelerated nuclear decay. In Vardiman et al. (2005), Chapter 2, pp. 41-45.) The justification for extrapolating from the high-temperature part of the Arrhenius down to the temperature of interest can be found in the seminal work by Fechtig and Kalbitzer

Quote:
... it is, therefore, allowed to extrapolate the straightline which represents the volume diffusion down to the temperatures investigators are most interested in. (Fechtig, H., Kalbitzer, S., 1966. The diffusion of argon in potassium-bearing solids. In Potassium Argon Dating, Schaeffer, O.A., Zähringer, J. (Ed.), Springer-Verlag, New York, p. 101.)
This insight opens up an entirely new possibility to our discussion. We can avoid the issue Humphreys has with Loechelt altogether by repeating the Fenton Hill analysis using diffusion data from another source, such as Reiners (2004). A single-domain diffusion model should be adequate as long as the kinetic parameters are extracted from the high-temperature part of the Arrhenius curve. For starters, let's compare the diffusion data between Humphreys (2004) and Reiners (2004).

Attachment 2023

In addition to the Arrhenius curve given by the average activation energy and diffusion prefactor, I have also plotted the Arrhenius curve extracted from sample 01CS15z 66 um (Wallowa Mountains). This particular sample happened to have the best match to the Fenton Hill data. Note that in their experiments, Reiners et al. never took their samples below 300 C. (The line on the graph is just an exponential fit to the data. To see the actual temperature steps, refer to table 1 of their paper.) I would like to know why Humphreys and his RATE colleagues insisted on having diffusion data at lower temperatures when his own experts never did so in their own publications.

In any event, the diffusion simulations can be repeated for the Fenton Hill zircons using the kinetic data from Reiners (2004) and the same geomety, boundary conditions, and thermal history. The results are shown below.

Attachment 2024

The Humphreys (2004) data were calculated using a multi-domain diffusion model based upon the RATE diffusion experiment, and the Reiners (2004) data were calculated using a single-domain diffusion model based upon the literature. Note that the diffusion simulations are robust in the sense that small changes in the diffusion kinetics do not drastically affect the outcome. The bottom line is that good agreement to the measured helium retention of Gentry is obtained for both experimental sources for the diffusion parameters, provided that the high-temperature data is used to extract the single-domain diffusion model. If one insists that the low-temperature data be included, as Humphreys did, then a multi-domain diffusion model must be used instead.

Let's now consider the implications of these results on Dave Hawkins' argument. His stand is that regardless of the other errors found in Humphrey's work, my work must be rejected because of this statement by Humphreys.

Quote:
Loechelt is right in claim (A), but wrong in claim (B). He overlooked part of one of his own quotes, in which an expert pointed out that loose helium would only affect the initial steps of the laboratory measurement, because after the initial steps the loose helium would be gone. That is one reason diffusion experts recommend ignoring the initial steps. Our experimenter recommended that, and that is exactly what we did. Thus he felt free to tell us that the rates he measured were accurate depictions of the leakiness for the other 98% of the helium. Ironically, our expert is one of those that Loechelt cites in his section about this issue. Loechelt either completely misunderstood the experts, or he deliberately distorted their meaning.
Regardless of whether one considers this statement by Humphreys to be right or wrong, this latest result renders it completely irrelevant. Humphreys cannot make any claim regarding my inappropriate use of a multi-domain diffusion model, because I have replicated the results of my original old-earth model with a simpler single-domain diffusion model. This model relies on the high-temperature steps of a diffusion experiment, and therefore makes no claims about the retention of loosely bound helium. Furthermore, regardless of what Humphreys' expert told him about the interpretation of his own experiment, that too is irrelevant, because I have now abandoned his work for a better dataset published in a credible academic journal by one of his own experts. And since Humphreys is no expert in the field of thermochronometry, he has no grounds to claim that I misinterpreted another persons work. I merely read the paper and used its results in my calculations. Humphreys objections are therefore rendered irrelevant. Are there any counter-arguments to this case? Dave, what are you thoughts?
Well first of all, since you expressed concern to me about some of my postings, let me apologize publicly for being a little rough on you and for being a little hasty in asserting that you are wrong about various issues. I also want to make it clear that I don't think you are intentionally trying to deceive people ... it may have sounded like I did think this when I complained about the misleading temperature graph. I believe that we all should treat each other with respect and I think we all fail to do this at times.

Secondly, I think it's important to focus on what the most critical issues are first, rather than pointing out this or that error which ultimately don't matter (for example, the temperature graph issue).

So what is the most important issue? My understanding is that it is the "leakiness of helium in zircons." Just how leaky is helium in zircons? That seems to be a good layman's way of framing the most important question. I had assumed that the answer was "very leaky" but I'm willing to consider your reasons for why you think this is not so. Be patient though ... it may take me some time.
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Old 05-25-2010, 02:52 PM   #942535  /  #14
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This is shaping up to be a classic. Like the time Supersport was misrepresenting a paper on epigenics, and the author of the paper showed up to tell SS he was full of shit.

Welcome Dr. Loechelt.
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Old 05-25-2010, 02:55 PM   #942537  /  #15
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Quote:
Originally Posted by Dave Hawkins View Post

Secondly, I think it's important to focus on what the most critical issues are first, rather than pointing out this or that error which ultimately don't matter (for example, the temperature graph issue).
There's the crux of the matter right there Dave. Science thinks the critical issue is to get the explanation right. You think the critical issue is to defend your religious dogma despite the evidence.

Science wins this one Dave, every time.
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Old 05-25-2010, 03:04 PM   #942545  /  #16
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Quote:
Originally Posted by Dave Hawkins View Post
Secondly, I think it's important to focus on what the most critical issues are first, rather than pointing out this or that error which ultimately don't matter (for example, the temperature graph issue).
do you understand the context in which Loechelt says that various things don't matter?

and why is that graph "screwy"?
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Old 05-25-2010, 03:22 PM   #942571  /  #17
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Quote:
Originally Posted by Dave Hawkins View Post
...Well first of all, since you expressed concern to me about some of my postings, let me apologize publicly for being a little rough on you and for being a little hasty in asserting that you are wrong about various issues.
"a little hasty"?
Quote:
I also want to make it clear that I don't think you are intentionally trying to deceive people ... it may have sounded like I did think this when I complained about the misleading temperature graph.
Now, are you making a distinction here between Dr. Loechelt and all those teachers and textbook authors whom you routinely accuse of lying to kids about biology and geology? If so, what exactly is that distinction?

Quote:
I believe that we all should treat each other with respect and I think we all fail to do this at times.

Hey, Dave. Do you know the definition of unctuous?
Quote:
Secondly, I think it's important to focus on what the most critical issues are first, rather than pointing out this or that error which ultimately don't matter (for example, the temperature graph issue).
You know, one of the minimum requirements of "respect" in a dialog is to pay attention to the other participants' input. It's been explained to you over and over and over - most recently by Dr. Loechelt - why the temperature graph issue is important.
You just ignored it.
Not respectful.
At all.
Quote:
... Be patient though ... it may take me some time.


Yeah.
If the obvious answer is not consistent with Dave's YECism, it will take an infinite amount of time.
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Old 05-25-2010, 03:25 PM   #942579  /  #18
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I wish dave kissed my ass that much when I make a long post which destroys his arguments....

...hmm, dave kissing my ass? on second thoughts, maybe not.
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Old 05-25-2010, 03:59 PM   #942658  /  #19
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Quote:
Originally Posted by Dave Hawkins View Post
It appears that he read a really screwy graph backwards, but doing so appears to have had no impact on the study at all. It appears to me that Loechelt is interested in a much longer time period that what that graph covers. Loechelt talks about 1 billion years and I think that graph only went back 1 million IIRC.
As both Loechelt and I pointed out and demonstrated before, Humphreys' misreading blows his old-earth model out of the water. It removes its foundation completely. Humphreys now has no old-earth model. That's a big impact, Davetie-wavetie. Humphreys' claims that his old-earth model is realistic and his young-earth model is better are falsified.

Loechelt's model demonstrates that the Fenton Hill zircons fit a realistic old-earth model quite well.

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Old 05-25-2010, 04:09 PM   #942671  /  #20
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Quote:
Originally Posted by Dave Hawkins View Post
So what is the most important issue? My understanding is that it is the "leakiness of helium in zircons." Just how leaky is helium in zircons?
The leakiness of healium in zircons depends. Mostly it depends on temperature. Dr. Loechelt's diffusion model describes how leaky helium is in zircons. See the first figure he posted, in his first message on the preceding page.

That's your answer. If you can't understand it, I'm not going to try to teach you a course in what diffusion is and how to read a logarithmic graph in this medium. Bestir your lazy ass and learn it yourself. ETA: start with Diffusion. ETA again: Note thaqt Humphreys reccomends Atomic migration in crystals .

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Old 05-25-2010, 04:16 PM   #942684  /  #21
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One request of the admins.

If you have to split this thread due to length (exceeding the 2,500 post limit) into part 2 then please split it BEFORE Dr. Loechelt joined.

Page 98 or 99 please.

Thanks,
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Old 05-25-2010, 04:21 PM   #942695  /  #22
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Quote:
Originally Posted by JonF View Post
Quote:
Originally Posted by Dave Hawkins View Post
So what is the most important issue? My understanding is that it is the "leakiness of helium in zircons." Just how leaky is helium in zircons?
The leakiness of healium in zircons depends. Mostly it depends on temperature. Dr. Loechelt's diffusion model describes how leaky helium is in zircons. See the first figure he posted, in his first message on the preceding page.

That's your answer. If you can't understand it, I'm not going to try to teach you a course in what diffusion is and how to read a logarithmic graph in this medium. Bestir your lazy ass and learn it yourself.
Ah, healium. The best medicine evah!
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Old 05-25-2010, 04:33 PM   #942703  /  #23
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Dave Hawkins in full deflection mode....
Quote:
Originally Posted by Dave Hawkins View Post
Secondly, I think it's important to focus on what the most critical issues are first, rather than pointing out this or that error which ultimately don't matter (for example, the temperature graph issue).
But he's replying to someone who has done their homework...
Quote:
Originally Posted by Loechelt View Post
Where did the RATE study go wrong?
...you have to focus on the high-temperature part of the Arrhenius curve. In the RATE study, they incorrectly focused on the low-temperature part of the Arrhenius curve.
....
A single-domain diffusion model should be adequate as long as the kinetic parameters are extracted from the high-temperature part of the Arrhenius curve.
....
Note that in their experiments, Reiners et al. never took their samples below 300 C. (The line on the graph is just an exponential fit to the data. To see the actual temperature steps, refer to table 1 of their paper.) I would like to know why Humphreys and his RATE colleagues insisted on having diffusion data at lower temperatures when his own experts never did so in their own publications.
....
The bottom line is that good agreement to the measured helium retention of Gentry is obtained for both experimental sources for the diffusion parameters, provided that the high-temperature data is used to extract the single-domain diffusion model. If one insists that the low-temperature data be included, as Humphreys did, then a multi-domain diffusion model must be used instead.
....
Humphreys cannot make any claim regarding my inappropriate use of a multi-domain diffusion model, because I have replicated the results of my original old-earth model with a simpler single-domain diffusion model. This model relies on the high-temperature steps of a diffusion experiment, and therefore makes no claims about the retention of loosely bound helium.
....
Are there any counter-arguments to this case? Dave, what are you thoughts?
No Dave. That temperature graph error is minor and sure doesn't matter at all.
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Old 05-25-2010, 04:43 PM   #942710  /  #24
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Quote:
Originally Posted by Loechelt
Quote:
Originally Posted by Dave Hawkins View Post
It appears that he read a really screwy graph backwards, but doing so appears to have had no impact on the study at all. It appears to me that Loechelt is interested in a much longer time period that what that graph covers. Loechelt talks about 1 billion years and I think that graph only went back 1 million IIRC.
It is not true that this mistake had no impact at all. Humphreys used it as the basis to determine the constant temperature in his uniformitarian model, which he extrapolated back 1.5 billion years. So essentially, he took the maximum temperature in a graph that covered a million years, and extended it by a factor of 1000X over a billion years without supplementing it with any data from that time period.
Perhaps being overly pedantic, but it appears to me that Humphreys read a change in temperature from Figure 9 of Harrison et. al. and added that to today's temperature to obtain a higher temperature. He then said (but see below)that this represented a "recent" heat pulse which lasted several million years and was preceded by 1.5 billion years of temperature so low that no significant diffusion took place. This justified his using a constant temperature at today's value to effectively obtain an upper bound (although he never explicitly stated this was his intention) on retained helium, which is much smaller than the measured helium, and therefore (in Humphreys' flawed model) the data could not be explained by an old-earrth model:

Quote:
Originally Posted by Humphreys, 2003
The effect of such heat pulses would be great. For several million years, the diffusion coefficients would have been about two to three orders of magnitude higher than today’s values. During the previous 1.5 billion years, supposedly at lower temperatures than today, the diffusion rates would have been on the “defect” line [Figure 4(a]) and therefore not much below today’s levels. Thus the long time at lower temperatures would not compensate for high losses during the few million years at higher temperatures. This makes our assumption of constant temperatures at today’s values quite favorable to the uniformitarian scenario.
In his calculation of uniformitarian diffusion coefficients (Table 3) he states he's integrating over 1.5 billion years, and it's not obvious to me what temperature variation with time that he's actually using.

Given that the model's foundation is so flawed, I doubt it's worth much effort ot figure it out.

Last edited by JonF; 05-25-2010 at 04:47 PM.
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Old 05-25-2010, 04:50 PM   #942716  /  #25
SomecallmeTim
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Get ready for the standard Hawkins bail-out:

"There's still lots of controversy about this, so we should wait until scientists investigate this more which I'm sure will confirm Humphreys was right!"
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