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Old 06-07-2010, 02:45 AM   #959182  /  #626
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You're back to being an arrogant prick again Dave.
Good to know that I haven't been one up to this point.
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Old 06-07-2010, 02:46 AM   #959184  /  #627
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You're back to being an arrogant prick again Dave.
Good to know that I haven't been one up to this point.
Make that an illiterate arrogant prick
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Old 06-07-2010, 02:49 AM   #959185  /  #628
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"still"?

You're new to the traveling Dave circus, aren't you Dr. L ?
I am trying to expect the best out of people.
Yet you accuse Humphreys of lying to Farley and cooking Magomedov's data?
I believe there is data out there that says he did. But, Loechelt prefers not to steal the fellow's thunder who proved this.

And, are you saying that you don't try to expect the best out of people? Because you routinely call people liars.
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Old 06-07-2010, 02:59 AM   #959194  /  #629
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"still"?

You're new to the traveling Dave circus, aren't you Dr. L ?
I am trying to expect the best out of people.
Yet you accuse Humphreys of lying to Farley and cooking Magomedov's data?
Dave, why did you lie about AND being a new topic for you?
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Old 06-07-2010, 03:25 AM   #959207  /  #630
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Dave,
This statement of yours makes zero sense.

Remember that the vacuum testing is used to measure the He diffusing out of a sample at different temperatures.

But in "real life" that He is in equilibrium with its surroundings. It's produced by U/Th decay and then diffuses out of the tight lattice structure of the zircon crystal. This is the tightly-bound area of zircons.
If the He produced appears in a defect then it diffuses fast-and-furious, through the defects and into the surrounding biotite which doesn't "hold onto" its He. This is the loosely-bound area of zircons.
There is ALSO He diffusing through the biotite from surrounding rock, which preferentially attaches itself to the surface of the zircon crystals. This is also loosely-bound.
But the AMOUNT of He in the loosely-bound regions is small because, well, its loosely-bound and diffuses out quickly.

So what does vacuum testing discover? That the tightly bound He in the zircon crystal only shows up at higher temperatures. And since in "real life" this is the flow of He we wish to measure then we only use the high temperature data.
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If you can arrive at Gentry's retention data with a 1.5 Ga time scale and 85C using Reiners data, then I will think that Humphreys is probably wrong. I would obviously give him a chance to defend himself, but you would have swayed me significantly.
Dave, please comment. I spent Friday and Saturday nights assembling these data per your request. I would like to know your thoughts. Do you still honor your word?
Actually, I figured out how to do the calculations myself (with Voxrat's help) and the calculations you made were not what I asked for but that's OK. I've figured out that the only way your old earth model has a chance at working is if you have very low temps (like 85C) and you extrapolate the high temp data and ignore the low temp data.
Well Dave, did you compare this result with the temperature history of Fenton Hill? Loechelt's paper has that history graph somewhere. Why don't you show that graph too while your trying to explain this.
Quote:
It seems doubtful to me that you can do this -- JonF has already admitted that vacuum testing is justified so this seems to mean that ANY data you get in a vacuum test is good ... you can't just cherry pick.
See my explanation above. To model "real life" you only use the high-temperature data. There is ANOTHER graph floating around that shows this quite clearly too. Your case is NOT supported with this graph.
Quote:
As for Reiners and Farley not doing low temp testing, I'm guessing that there is some reason other than "it's not valid" ... I do know that they are interested in (U-Th)/He chronometry and I'm pretty sure they have NO interest in He diffusion dating so I'm thinking the reason they don't take their tests lower maybe has something to do with this.
How about.... "Farley and Reiners were only interested in aquiring the high-temperature data because that is the only data required to model the diffusion at lower temperatures."

Does that sound like an echo? It should.
Quote:
You apparently don't know the reason yet you seem to be sure that this data should be ignored. So my challenge now is to try to figure out why Reiners and Farley don't test at lower temps and see if it has any relevance to the present discussion.
Dave,
No scientist that I know of "ignores" data. They may not utilize the data (because in this case the low-temperature diffusion data doesn't enter into the models they are constructing, for valid reasons) but they don't "ignore" the data.

What you're saying here is really that Humphreys, for some reason or another, is now JUSTIFIED in extrapolating the low-temperature lab data to model the "real world" scenario. While others in the field, since 1966, have published paper after paper after book after finding after conclusion to say quite clearly that you only use the high-temperature data. Talk about trying to overturn science. But Humphreys is incorrect in this case for the reasons I outlined above.
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Old 06-07-2010, 04:00 AM   #959233  /  #631
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I am trying to expect the best out of people.
Yet you accuse Humphreys of lying to Farley and cooking Magomedov's data?
I believe there is data out there that says he did. But, Loechelt prefers not to steal the fellow's thunder who proved this.

And, are you saying that you don't try to expect the best out of people? Because you routinely call people liars.
Routinely? Who have I called a liar? Can you name even one with no help from others?
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Old 06-07-2010, 04:16 AM   #959241  /  #632
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Meanwhile ... while I am waiting to figure out why Reiners and Farley don't care about low temp testing ...

LET'S PLAY WITH EQUATION 16

Q/Qo = a^2 / (15Dt)

What effect would a pulse of heat have? (Assuming for the moment that it's valid to extrapolate high temp data)

Well if the pulse is 100,000 years long and the temp = 300C (100 above present at 2900m), we get Q/Qo = 0.0002 ... MUCH smaller than that observed for Sample 3. (I picked Sample 3 because that's the temp Humphreys picked for his uniformitarian model)

Check my math, but it looks like a heat pulse like this would wipe out the helium.
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Old 06-07-2010, 04:21 AM   #959243  /  #633
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Yet you accuse Humphreys of lying to Farley and cooking Magomedov's data?
I believe there is data out there that says he did. But, Loechelt prefers not to steal the fellow's thunder who proved this.

And, are you saying that you don't try to expect the best out of people? Because you routinely call people liars.
Routinely? Who have I called a liar? Can you name even one with no help from others?
Ahem...

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Oh and dave, whenever you decide to come clean, post the receipt from the $500 check you'll send to a non-creationist charity institution. Since you clearly lost the bet.

Faid .... You are the biggest liar and welsher I've ever met. You said that there was no French influence except for a few loaner words. Which, of course, is preposterous. Do you deny that you said this?
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Why did you bother asking?
Because I wanted a good laugh. I think you're a liar. You wouldn't accept anything.
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Deal.
I need to be sure you understand what this "deal" means, Dave, before I go to this considerable effort.

It means not behaving as you did in the EE with MikePSS, where he went to considerable effort to dig up data that showed you (and Austin) were wrong. And you ended up, with no data to counter that, saying you "think Austin is right" anyway.

Do you understand that?
You're wrong again. You sure are wrong alot for a guy with a PhD. I DID come up with more data. And you know I did. So now you are a liar. And don't give me this nonsense about the science writer didn't know what he was talking about. That tired dog doesn't hunt with me.
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Old 06-07-2010, 04:32 AM   #959248  /  #634
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Routinely? Who have I called a liar? Can you name even one with no help from others?
Why the caveat Davie-doodles? If others point out cases of you calling people liars, does that somehow invalidate them?

Speaking of liars Dave, are you ever going to tell us why you lied about having never heard of AND? I'm really curious how you think you can get away with such blatant lying when everyone has access to the search function.
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Old 06-07-2010, 05:12 AM   #959264  /  #635
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"still"?

You're new to the traveling Dave circus, aren't you Dr. L ?
I am trying to expect the best out of people.
Yet you accuse Humphreys of lying to Farley and cooking Magomedov's data?
Farley accused Humphreys of lying. His accusation is supported by Humphreys' own published writings.
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Old 06-07-2010, 05:32 AM   #959268  /  #636
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If you can arrive at Gentry's retention data with a 1.5 Ga time scale and 85C using Reiners data, then I will think that Humphreys is probably wrong. I would obviously give him a chance to defend himself, but you would have swayed me significantly.
Dave, please comment. I spent Friday and Saturday nights assembling these data per your request. I would like to know your thoughts. Do you still honor your word?
Actually, I figured out how to do the calculations myself (with Voxrat's help) and the calculations you made were not what I asked for but that's OK. I've figured out that the only way your old earth model has a chance at working is if you have very low temps (like 85C) and you extrapolate the high temp data and ignore the low temp data. It seems doubtful to me that you can do this -- JonF has already admitted that vacuum testing is justified so this seems to mean that ANY data you get in a vacuum test is good ... you can't just cherry pick. As for Reiners and Farley not doing low temp testing, I'm guessing that there is some reason other than "it's not valid" ... I do know that they are interested in (U-Th)/He chronometry and I'm pretty sure they have NO interest in He diffusion dating so I'm thinking the reason they don't take their tests lower maybe has something to do with this. You apparently don't know the reason yet you seem to be sure that this data should be ignored. So my challenge now is to try to figure out why Reiners and Farley don't test at lower temps and see if it has any relevance to the present discussion. As for the abstract you posted, I guess I'm not following what your point was for posting it. Could you restate that?
Several points Dave.

1. I explicitly asked if I could make the comparison using diffusion data from Reiners (2004), and you agreed. Now you are basically saying I can't use that data, even though it was published in a prestigious peer-reviewed journal. Why the change?

2. Your statement that I "don't know the reason" why the low-temperature data is not used in the analysis is a complete lie. I stated good reasons in my very first post to this thread, as has been pointed out to you now by several people on multiple occasions.

3. I think the burden lies with you or Humphreys to explain why obtaining the low-temperature data was so important, not the other way around. My challenge to you is to stop asking everyone questions and starting answering the legitimate ones others have raised.
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Old 06-07-2010, 05:45 AM   #959269  /  #637
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Quote:
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Meanwhile ... while I am waiting to figure out why Reiners and Farley don't care about low temp testing ...

LET'S PLAY WITH EQUATION 16

Q/Qo = a^2 / (15Dt)

What effect would a pulse of heat have? (Assuming for the moment that it's valid to extrapolate high temp data)

Well if the pulse is 100,000 years long and the temp = 300C (100 above present at 2900m), we get Q/Qo = 0.0002 ... MUCH smaller than that observed for Sample 3. (I picked Sample 3 because that's the temp Humphreys picked for his uniformitarian model)

Check my math, but it looks like a heat pulse like this would wipe out the helium.
Your math does not even have the respectability of being wrong. This equation is derived from the general diffusion equation in the steady-state limit. How do you propose to have a pulse of heat in a steady-state equation? That is pure nonsense. Why don't you look at the spreadsheet I e-mailed to you. I show you how to solve the diffusion equation a little more accurately.
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Old 06-07-2010, 06:17 AM   #959276  /  #638
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For those who are still interested in looking at some new data, I have read the recent paper.

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
As the title says, the paper covers both (U-Th)/He thermochronometry and helium diffusion. In their laboratory step-wise heating diffusion experiment, they do not explore temperatures below 400 C, which is higher than the 300 C used by Reiners. One of the goals of the paper is to test the validity of using high-temperature laboratory data to model diffusion in the field at lower temperatures over long periods of time. Here is a good quote.

Quote:
Conventional bulk He diffusion kinetics in zircon are determined by laboratory step-heating experiments employing steps with isothermal holding times between 0.5 and 12 h at temperatures between ∼400 and 700 °C and then extrapolated over several order of magnitude to geological time scales, assuming identical diffusion behavior.
In their introduction, they explain the motivation behind the study.

Quote:
... there are significant outstanding questions regarding He diffusion kinetics in zircon, such as ...

4) the validity of laboratory diffusion experiments conducted at high temperatures and short time steps to geologically pertinent temperatures (< 250 °C) and timescales.
Their approach was to compare the helium content of zircons down the drill hole (similar to Gentry's experiment) to forward diffusion modeling (similar to what I did) using laboratory extracted diffusion parameters (similar to Farley's and Reiners' experiments). The only difference is that they express the comparison in terms of the effective He age instead of a Q/Qo ratio like Gentry. As they state in the abstract.

Quote:
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.
In other words, forward modeling results using a diffusivity extrapolated from the high-temperature steps of a laboratory experiment are a good predictor of the helium retained in field samples at low-temperatures over long periods of time.
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Old 06-07-2010, 06:18 AM   #959278  /  #639
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You're back to being an arrogant prick again Dave.
Good to know that I haven't been one up to this point.
Make that an illiterate arrogant prick
Again. As you indicated originally.

Again, as in have been, weren't so much so for a bit and are once more.

Illiterate is right. But just another characteristic of creaIDiots.
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Old 06-07-2010, 07:34 AM   #959288  /  #640
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JonF has already admitted that vacuum testing is justified so this seems to mean that ANY data you get in a vacuum test is good .
first of all, was that comment by JonF peer reviewed? If not, then why are you trusting it, after all he made a mistake before and you used that as a basis to ignore other comments of his.

Secondly, no it doesn't mean that all features from the graph will translate to the wild situation..

I ask you again; what does the instrinsic line mean, and what does the defect line mean?

Can you explain this: if the tightly bound helium takes a random walk through the zircon lattice, with the diffusion rate increasing with temperature, how will the temperature affect the walk through the lattice, and why?

I know you are ignoring me, and the repetition of this question is largely for the benefit of those who are asking you complicated questions. You are making statements that rely on your knowledge of the answers to these questions,and frankly I don't think you know. I am asking these so that hopefully others work out that you don't know the answers either and force you to try to answer them, and thus reveal the fundamental flaws in your thinking.
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Old 06-07-2010, 11:44 AM   #959317  /  #641
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Yet you accuse Humphreys of lying to Farley and cooking Magomedov's data?
I believe there is data out there that says he did. But, Loechelt prefers not to steal the fellow's thunder who proved this.

And, are you saying that you don't try to expect the best out of people? Because you routinely call people liars.
Routinely? Who have I called a liar? Can you name even one with no help from others?
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This would make a fascinating discussion, but I know that people here will simply turn this into an argument.
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Old 06-07-2010, 12:16 PM   #959323  /  #642
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Yup ... too much work ... love to tackle it, but not now.
So you have time to disparage the professionalism and integrity of the scientists who were willing to actually do the work in the first place but you aren't willing to do the work to back up your libel.

You aren't just ignorant; you're immoral.
Hey! That reminds me:
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bump.

Dave?
A year and a half and counting.
Aren't you being just a tad... what's the word I'm looking for? ... hypocritical here?
Bump, Dave.

Dave?
Oh, brother...

Bump, Dave.

Bump, Bump,, Bump, Bump!
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Old 06-07-2010, 12:43 PM   #959340  /  #643
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Meanwhile ... while I am waiting to figure out why Reiners and Farley don't care about low temp testing ...
Why are you waiting Dave?

People have answered this multiple times ITT.
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Old 06-07-2010, 12:48 PM   #959342  /  #644
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I am trying to expect the best out of people.
Yet you accuse Humphreys of lying to Farley and cooking Magomedov's data?
Farley accused Humphreys of lying. His accusation is supported by Humphreys' own published writings.
Where is this accusation written? How is it supported by Humphreys own writings?
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Old 06-07-2010, 01:05 PM   #959347  /  #645
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Dave, please comment. I spent Friday and Saturday nights assembling these data per your request. I would like to know your thoughts. Do you still honor your word?
Actually, I figured out how to do the calculations myself (with Voxrat's help) and the calculations you made were not what I asked for but that's OK. I've figured out that the only way your old earth model has a chance at working is if you have very low temps (like 85C) and you extrapolate the high temp data and ignore the low temp data. It seems doubtful to me that you can do this -- JonF has already admitted that vacuum testing is justified so this seems to mean that ANY data you get in a vacuum test is good ... you can't just cherry pick. As for Reiners and Farley not doing low temp testing, I'm guessing that there is some reason other than "it's not valid" ... I do know that they are interested in (U-Th)/He chronometry and I'm pretty sure they have NO interest in He diffusion dating so I'm thinking the reason they don't take their tests lower maybe has something to do with this. You apparently don't know the reason yet you seem to be sure that this data should be ignored. So my challenge now is to try to figure out why Reiners and Farley don't test at lower temps and see if it has any relevance to the present discussion. As for the abstract you posted, I guess I'm not following what your point was for posting it. Could you restate that?
Several points Dave.

1. I explicitly asked if I could make the comparison using diffusion data from Reiners (2004), and you agreed. Now you are basically saying I can't use that data, even though it was published in a prestigious peer-reviewed journal. Why the change?

2. Your statement that I "don't know the reason" why the low-temperature data is not used in the analysis is a complete lie. I stated good reasons in my very first post to this thread, as has been pointed out to you now by several people on multiple occasions.

3. I think the burden lies with you or Humphreys to explain why obtaining the low-temperature data was so important, not the other way around. My challenge to you is to stop asking everyone questions and starting answering the legitimate ones others have raised.
1) I'm not sure why I agreed to that. At the moment, I don't see a justification for ignoring the low temp data.
2) Now I'm a liar in addition to Humphreys. Great. That's OK ... I'm used to being falsely accused around here ... I won't get mad like you did. Honestly, I do not remember you giving a reason for Reiners and Farley not doing low temp testing ... I remember you saying something like "they didn't so that should tell you something"
3) How can I answer questions if I don't know the answers? I'm trying to understand the Old Earth model here and the only way I know to learn is read and ask questions.
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Old 06-07-2010, 01:07 PM   #959348  /  #646
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Meanwhile ... while I am waiting to figure out why Reiners and Farley don't care about low temp testing ...

LET'S PLAY WITH EQUATION 16

Q/Qo = a^2 / (15Dt)

What effect would a pulse of heat have? (Assuming for the moment that it's valid to extrapolate high temp data)

Well if the pulse is 100,000 years long and the temp = 300C (100 above present at 2900m), we get Q/Qo = 0.0002 ... MUCH smaller than that observed for Sample 3. (I picked Sample 3 because that's the temp Humphreys picked for his uniformitarian model)

Check my math, but it looks like a heat pulse like this would wipe out the helium.
Your math does not even have the respectability of being wrong. This equation is derived from the general diffusion equation in the steady-state limit. How do you propose to have a pulse of heat in a steady-state equation? That is pure nonsense. Why don't you look at the spreadsheet I e-mailed to you. I show you how to solve the diffusion equation a little more accurately.
Fair enough. I'll have a look.
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Old 06-07-2010, 01:12 PM   #959349  /  #647
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For those who are still interested in looking at some new data, I have read the recent paper.

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
As the title says, the paper covers both (U-Th)/He thermochronometry and helium diffusion. In their laboratory step-wise heating diffusion experiment, they do not explore temperatures below 400 C, which is higher than the 300 C used by Reiners. One of the goals of the paper is to test the validity of using high-temperature laboratory data to model diffusion in the field at lower temperatures over long periods of time. Here is a good quote.

Quote:
Conventional bulk He diffusion kinetics in zircon are determined by laboratory step-heating experiments employing steps with isothermal holding times between 0.5 and 12 h at temperatures between ∼400 and 700 °C and then extrapolated over several order of magnitude to geological time scales, assuming identical diffusion behavior.
In their introduction, they explain the motivation behind the study.

Quote:
... there are significant outstanding questions regarding He diffusion kinetics in zircon, such as ...

4) the validity of laboratory diffusion experiments conducted at high temperatures and short time steps to geologically pertinent temperatures (< 250 °C) and timescales.
Their approach was to compare the helium content of zircons down the drill hole (similar to Gentry's experiment) to forward diffusion modeling (similar to what I did) using laboratory extracted diffusion parameters (similar to Farley's and Reiners' experiments). The only difference is that they express the comparison in terms of the effective He age instead of a Q/Qo ratio like Gentry. As they state in the abstract.

Quote:
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.
In other words, forward modeling results using a diffusivity extrapolated from the high-temperature steps of a laboratory experiment are a good predictor of the helium retained in field samples at low-temperatures over long periods of time.
Wonderful. But nothing in there about WHY it's justified to extrapolate the high temp data. Only a statement that is IS. Notice their vageness ...
Quote:
... there are significant outstanding questions regarding He diffusion kinetics in zircon, such as ...

4) the validity of laboratory diffusion experiments conducted at high temperatures and short time steps to geologically pertinent temperatures (< 250 °C) and timescales.
They don't get specific at all ... they just question the validity.

Please get specific Dr. Loechelt!
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Old 06-07-2010, 01:13 PM   #959350  /  #648
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I have a theory for why these folks keep insisting that low temp testing is invalid but won't tell us why ...

THEY KNOW THE IMPLICATIONS!
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Old 06-07-2010, 01:16 PM   #959351  /  #649
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Actually, I figured out how to do the calculations myself (with Voxrat's help) and the calculations you made were not what I asked for but that's OK. I've figured out that the only way your old earth model has a chance at working is if you have very low temps (like 85C) and you extrapolate the high temp data and ignore the low temp data. It seems doubtful to me that you can do this -- JonF has already admitted that vacuum testing is justified so this seems to mean that ANY data you get in a vacuum test is good ... you can't just cherry pick. As for Reiners and Farley not doing low temp testing, I'm guessing that there is some reason other than "it's not valid" ... I do know that they are interested in (U-Th)/He chronometry and I'm pretty sure they have NO interest in He diffusion dating so I'm thinking the reason they don't take their tests lower maybe has something to do with this. You apparently don't know the reason yet you seem to be sure that this data should be ignored. So my challenge now is to try to figure out why Reiners and Farley don't test at lower temps and see if it has any relevance to the present discussion. As for the abstract you posted, I guess I'm not following what your point was for posting it. Could you restate that?
Several points Dave.

1. I explicitly asked if I could make the comparison using diffusion data from Reiners (2004), and you agreed. Now you are basically saying I can't use that data, even though it was published in a prestigious peer-reviewed journal. Why the change?

2. Your statement that I "don't know the reason" why the low-temperature data is not used in the analysis is a complete lie. I stated good reasons in my very first post to this thread, as has been pointed out to you now by several people on multiple occasions.

3. I think the burden lies with you or Humphreys to explain why obtaining the low-temperature data was so important, not the other way around. My challenge to you is to stop asking everyone questions and starting answering the legitimate ones others have raised.
1) I'm not sure why I agreed to that. At the moment, I don't see a justification for ignoring the low temp data.
2) Now I'm a liar in addition to Humphreys. Great. That's OK ... I'm used to being falsely accused around here ... I won't get mad like you did. Honestly, I do not remember you giving a reason for Reiners and Farley not doing low temp testing ... I remember you saying something like "they didn't so that should tell you something"
3) How can I answer questions if I don't know the answers? I'm trying to understand the Old Earth model here and the only way I know to learn is read and ask questions.
Quite so, Dave -. . but frequently you fail to read the posts posted and the links given. I'm not sure if it's laziness, or inattention to detail, or fear of what you might see.
And you certainly seem reluctant to question the likes of Humphreys and Baumgardner in the way you question non-creationists - although I do realise that it is very difficult to winkle any detail out of the creo-heroes.

Ever wondered why they are so reluctant to engage in a public debate like this one? I think it's because, on the very few occasions they have, they are shown to be wrong. What do you think, Dave?
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Old 06-07-2010, 01:21 PM   #959354  /  #650
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2) Now I'm a liar in addition to Humphreys.
Yes Dave, you are a liar. Demonstrably so.
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