Let's take a look at another example of "junk" science by our YEC brothers.
http://www.icr.org/research/icc03/pdf/Helium_ICC_7-22-03.pdf
In this Humphreys, Austin, Snelling, and Peczkis... I mean ... and Baumgardner claimed that helium diffusion rates in zircons indicated a young earth. I'll just reproduce the abstract here.
The first problem is this. The base their claims on the assumption of how much helium would be produced by old earth assumptions of the age of the earth. If the earth really is 6000 years old, just why is there an appreciable amount of helium in the rocks to begin with? Their answer? Accelerated decay. They suppose that billions of years worth of decay happened in a very short time. Now, two problems. There is no known way to explain how the decay would have been accelerated. Second, such accelerated decay causes major problems in removing the accompanying heat release. But reality has never been an obstacle to the RATE group as shown in earlier posts. Not only that, but how was the formation of all these layers times just so making the apparent seem to show formation over long periods of time. Just how did those layers get sorted according to their ratios of radioactive isotopes?
Here is the next problem, and the biggie. What they are saying is that the zircons should not contain so much helium because it should have leaked out by now through diffusion. So they need to measure the diffusion rates. The temperatures of their samples were 105, 151, 197, 239, 277, and 313 Celcius. But at these low temperatures, the diffusion rate is too low to accurately measure. Diffusion rates increase with temperature. So they had the zircons tested at 300 - 500 C to see what the diffusion rates were there.
Now look closely what they do. As stated, diffusion rates increase with temperature. The higher the rate, the more easy it is to measure accurately. Now, they decide to only use the diffusion data from 300 - 440 C when extrapolating down to the lower temperatures. This is because if you include the higher temperatures, the ones that should be more accurate, you get ages that are much less favorable to their position.
But there is a related problem. The more of a substance that you have, the easier it is to measure it. In the case of their zircons, the samples at 239, 277, and 313 C were at or close to the detection limits for the lab and therefore have a very large potential error associated with them. In contrast the samples at 105, 151, and 197 C had high levels of He which would be easily measured and therefore more accurate. In fact, the highest two temperature zircons had only estimated given without even error ranges associated. The RATE group at least dropped the highest of these, the 313 C sample. Is this because they were trying to be honest with the data or was it was because the "age" they would then measure would be so young as to expose the problems of their method?
So for the remaining 5 samples, if you use their methodology to calculate ages, first with their limited diffusion data set and then with the whole range of the diffusion measurmentsm you get the following table.
Temp (C)....Age (all temp)......Age (440-300 C)
105........46,800,000..........3,400,000
151........1,350,000...........195,000
197........132,000.............11,000
239........16,600..............6,750
277 ........8,700..............4,850
So, even with their cherrypicking of data favorable to them, the ages range from 4800 years to 3.4 million. Which do you think they choose? With the better diffusion data added back in, the age estimates go up to 47 million years. And notice that the young ages are only with the smaples in which the level of He was the most difficult to measure and which had the largest potential error. The more reliable measurements yield much older ages. And these old ages are for the less deep and therefore younger rocks.
Besides the problem with their handling of the data, there are other potential pitfalls. One of the most important is that the area in which the samples were taken is known for having high enough levels of helium in the ground that it can be "mined." If these samples had abnormally high levels of helium around them, then the driving force for the diffusion is removed and in fact, the rocks could have helium diffusion into the rocks. In addition, radiocative decay proceeds through a number of intermediate steps. When the decay starts, it takes about 10 half-lives for the longest half-life intermediates to come to equilibrium. If the decay rates had been changed in the past, the isotopes in the rocks should not yet be back in equlibrium. This should be easy to test. Has it been done?
I used the following as a source for the result of calculations and as a general guide.
http://groups.google.com/groups?q=%22The+basic+science+involved+is+that+fact+that%22+group:talk.origins&hl=en&lr=&ie=UTF-8&group=talk.origins&selm=e4204a90.0404120335.61b0a055%40po sting.google.com&rnum=1
http://www.icr.org/research/icc03/pdf/Helium_ICC_7-22-03.pdf
In this Humphreys, Austin, Snelling, and Peczkis... I mean ... and Baumgardner claimed that helium diffusion rates in zircons indicated a young earth. I'll just reproduce the abstract here.
Now let's begin to look at the claims in detail.Two decades ago, Robert Gentry and his colleagues at Oak Ridge National Laboratory reported surprisingly high amounts of nuclear-decay-generated helium in tiny radioactive zircons recovered from Precambrian crystalline rock, the Jemez Granodiorite on the west flank of the volcanic Valles Caldera near Los Alamos, New Mexico [9]. Up to 58% of the helium (that radioactivity would have generated during the alleged 1.5 billion year age of the granodiorite) was still in the zircons. Yet the zircons were so small that they should not have retained the helium for even a tiny fraction of that time. The high helium retention levels suggested to us and many other creationists that the helium simply had not had enough time to diffuse out of the zircons, and that recent accelerated nuclear decay had produced over a billion years worth of helium within only the last few thousand years, during Creation and/or the Flood. Such acceleration would reduce the radioisotopic time scale from megayears down to months.
The first problem is this. The base their claims on the assumption of how much helium would be produced by old earth assumptions of the age of the earth. If the earth really is 6000 years old, just why is there an appreciable amount of helium in the rocks to begin with? Their answer? Accelerated decay. They suppose that billions of years worth of decay happened in a very short time. Now, two problems. There is no known way to explain how the decay would have been accelerated. Second, such accelerated decay causes major problems in removing the accompanying heat release. But reality has never been an obstacle to the RATE group as shown in earlier posts. Not only that, but how was the formation of all these layers times just so making the apparent seem to show formation over long periods of time. Just how did those layers get sorted according to their ratios of radioactive isotopes?
Here is the next problem, and the biggie. What they are saying is that the zircons should not contain so much helium because it should have leaked out by now through diffusion. So they need to measure the diffusion rates. The temperatures of their samples were 105, 151, 197, 239, 277, and 313 Celcius. But at these low temperatures, the diffusion rate is too low to accurately measure. Diffusion rates increase with temperature. So they had the zircons tested at 300 - 500 C to see what the diffusion rates were there.
Now look closely what they do. As stated, diffusion rates increase with temperature. The higher the rate, the more easy it is to measure accurately. Now, they decide to only use the diffusion data from 300 - 440 C when extrapolating down to the lower temperatures. This is because if you include the higher temperatures, the ones that should be more accurate, you get ages that are much less favorable to their position.
But there is a related problem. The more of a substance that you have, the easier it is to measure it. In the case of their zircons, the samples at 239, 277, and 313 C were at or close to the detection limits for the lab and therefore have a very large potential error associated with them. In contrast the samples at 105, 151, and 197 C had high levels of He which would be easily measured and therefore more accurate. In fact, the highest two temperature zircons had only estimated given without even error ranges associated. The RATE group at least dropped the highest of these, the 313 C sample. Is this because they were trying to be honest with the data or was it was because the "age" they would then measure would be so young as to expose the problems of their method?
So for the remaining 5 samples, if you use their methodology to calculate ages, first with their limited diffusion data set and then with the whole range of the diffusion measurmentsm you get the following table.
Temp (C)....Age (all temp)......Age (440-300 C)
105........46,800,000..........3,400,000
151........1,350,000...........195,000
197........132,000.............11,000
239........16,600..............6,750
277 ........8,700..............4,850
So, even with their cherrypicking of data favorable to them, the ages range from 4800 years to 3.4 million. Which do you think they choose? With the better diffusion data added back in, the age estimates go up to 47 million years. And notice that the young ages are only with the smaples in which the level of He was the most difficult to measure and which had the largest potential error. The more reliable measurements yield much older ages. And these old ages are for the less deep and therefore younger rocks.
Besides the problem with their handling of the data, there are other potential pitfalls. One of the most important is that the area in which the samples were taken is known for having high enough levels of helium in the ground that it can be "mined." If these samples had abnormally high levels of helium around them, then the driving force for the diffusion is removed and in fact, the rocks could have helium diffusion into the rocks. In addition, radiocative decay proceeds through a number of intermediate steps. When the decay starts, it takes about 10 half-lives for the longest half-life intermediates to come to equilibrium. If the decay rates had been changed in the past, the isotopes in the rocks should not yet be back in equlibrium. This should be easy to test. Has it been done?
I used the following as a source for the result of calculations and as a general guide.
http://groups.google.com/groups?q=%22The+basic+science+involved+is+that+fact+that%22+group:talk.origins&hl=en&lr=&ie=UTF-8&group=talk.origins&selm=e4204a90.0404120335.61b0a055%40po sting.google.com&rnum=1