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Author | Topic: Earth science curriculum tailored to fit wavering fundamentalists | |||||||||||||||||||||||||||||||||||||||||||||||
kbertsche Member (Idle past 2162 days) Posts: 1427 From: San Jose, CA, USA Joined: |
It is probably the best description of science that I have ever seen.
* drums fingers on desk, awaits dissent * If you (or anyone else here) has problems with MacKay's description of science, please explain what you disagree with. "Science without religion is lame, religion without science is blind." — Albert Einstein I am very astonished that the scientific picture of the real world around me is very deficient. It gives us a lot of factual information, puts all of our experience in a magnificently consistent order, but it is ghastly silent about all and sundry that is really near to our heart, that really matters to us. It cannot tell us a word about red and blue, bitter and sweet, physical pain and physical delight; it knows nothing of beautiful and ugly, good or bad, God and eternity. Science sometimes pretends to answer questions in these domains, but the answers are very often so silly that we are not inclined to take them seriously. — Erwin Schroedinger
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kbertsche Member (Idle past 2162 days) Posts: 1427 From: San Jose, CA, USA Joined: |
I know that C14 is produced by nitrogen being bombarded with radiation (layman description). I know that the most common impurity in diamonds is nitrogen. I know that decay in rocks produce measurable radiation. Do these puzzle pieces fit together? A: if I take a diamond with nitrogen impurities in it and bombard it with radiation (either lab, or take it to upper atmosphere or whatever) will it contain a fresh dose of measurable C14? B: If a diamond is positioned underground near a geological formation that is producing radiation, will there be a somewhat constant replenishment of C14 in the diamond? Again, I'm not trying to assert that this was the issue with the RATE diamonds, I'm just trying to figure out what would happen in the above scenarios.. I wouldn't expect much if any N in diamond. As a crystal crystallizes, it tends to push impurities away. Impurities generally mess up the crystal structure, so they end up at grain boundaries between crystals. (Coal is a different story; coal can have high levels of nitrogen.). {ABE: I misspoke here. N can be incorporated into the crystal lattice of diamond, so is not all pushed away.} N-14 has a high "cross section" for an (n,p) reaction, producing C-14. So if any nitrogen is present and there is a neutron source (e.g. Uranium or thorium) nearby, some C-14 will be created. I also highly recommend the Taylor & Southon paper. It's pretty terse; you'll need to read it a few times to get what they are saying. Throughout their paper they comment that the radiocarbon they measure does not actually come from inside the diamond, but from the surface of the diamond (due to ion source contamination) and from the instrument. In fact, this was the whole purpose of their experiment; since diamond is hydrophobic they reasoned that it would exhibit less ion source contamination than graphite does. (BTW, John Baumgardner of the RATE project finally commented on my explanations of "radiocarbon in diamonds" and the Taylor & Southon paper a few months ago. His comments were featured on the Answers In Genesis website just a few weeks back. I encourage you to read his comments next to the Taylor & Southon paper. You'll see that Baumgardner mischaracterizes and misinterprets what they wrote.) Edited by kbertsche, : Added correction about N in diamond and comments about neutron range in solids. Edited by kbertsche, : No reason given. Edited by kbertsche, : Corrected neutron range comments after coffee. Edited by kbertsche, : Deleted comments about neutron range after more coffee."Science without religion is lame, religion without science is blind." — Albert Einstein I am very astonished that the scientific picture of the real world around me is very deficient. It gives us a lot of factual information, puts all of our experience in a magnificently consistent order, but it is ghastly silent about all and sundry that is really near to our heart, that really matters to us. It cannot tell us a word about red and blue, bitter and sweet, physical pain and physical delight; it knows nothing of beautiful and ugly, good or bad, God and eternity. Science sometimes pretends to answer questions in these domains, but the answers are very often so silly that we are not inclined to take them seriously. — Erwin Schroedinger
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kbertsche Member (Idle past 2162 days) Posts: 1427 From: San Jose, CA, USA Joined: |
Interesting. Most of the literature I've seen indicates that Nitrogen and Boron can be incorporated into a diamond lattice, but rarely show up as interstitial impurities.
Oops, maybe I spoke too quickly. Wikipedia has a nice discussion of impurities in diamond; apparently nitrogen can be incorporated into the crystal lattice in amounts up to about 1%. This is higher than I thought."Science without religion is lame, religion without science is blind." — Albert Einstein I am very astonished that the scientific picture of the real world around me is very deficient. It gives us a lot of factual information, puts all of our experience in a magnificently consistent order, but it is ghastly silent about all and sundry that is really near to our heart, that really matters to us. It cannot tell us a word about red and blue, bitter and sweet, physical pain and physical delight; it knows nothing of beautiful and ugly, good or bad, God and eternity. Science sometimes pretends to answer questions in these domains, but the answers are very often so silly that we are not inclined to take them seriously. — Erwin Schroedinger
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kbertsche Member (Idle past 2162 days) Posts: 1427 From: San Jose, CA, USA Joined: |
Thanks Coyote. All I can find is a paywall for that article. Anyone have a copy? TIA
I sent you a copy.JB "Science without religion is lame, religion without science is blind." — Albert Einstein I am very astonished that the scientific picture of the real world around me is very deficient. It gives us a lot of factual information, puts all of our experience in a magnificently consistent order, but it is ghastly silent about all and sundry that is really near to our heart, that really matters to us. It cannot tell us a word about red and blue, bitter and sweet, physical pain and physical delight; it knows nothing of beautiful and ugly, good or bad, God and eternity. Science sometimes pretends to answer questions in these domains, but the answers are very often so silly that we are not inclined to take them seriously. — Erwin Schroedinger
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kbertsche Member (Idle past 2162 days) Posts: 1427 From: San Jose, CA, USA Joined: |
The 14C detected levels correlate with radioactivity, varying widely for coals of the same approximate age.
I agree that U and other radiation can create C-14 in-situ. But according to my calculations, the amounts are quite small. I have not been able to find data on the relative amounts of U in diamond deposits (maybe someone can find some data on this?). Below are my calculations for C-14 production in coal. I welcome any corrections to either my data or my calculations. There is also information of 14C production in the carbon rods used in nuclear reactors (and spent rods have high radioactivity) And it should be obvious that any effect on one sample of old carbon can be applied to all others such samples (coal, oil, diamonds, etc) So there is a LOT of evidence of radioactivity causing 14C in old carbon. 1) simplifying assumption: we will assume that every neutron released ends up in an (n,p) reaction with an N-14 atom to produce C-14. This will somewhat overestimate the amount of C-14 produced. But it will be a reasonable approximation under the following conditions: 1) there is more than ~0.3% nitrogen in the coal, and 2) there is no more than ~6x as much hydrogen as nitrogen in the coal. {This is based on thermal neutron cross sections of about 5 mBarn for (n,gamma) on C-12, 300 mBarn for (n,gamma) on H-1, and 1.8 Barn for (n,p) on N-14. See http://www.iaea.org/...tionStore/_Public/28/060/28060364.pdf , The14N(n, p)14C reaction cross section for thermal neutrons | SpringerLink } 2) approach: the system will eventually come to a steady state condition where the rate of C-14 creation is the same as the rate of C-14 decay. Under our simplifying assumption, this will happen when the rate of C-14 creation is the same as the rate of neutron emission. So we need to calculate the rate of neutron emission, equate it to the rate of C-14 decay, and see how much C-14 this corresponds to. 3) U content: According to the USGS U.S. coal typically has about 1 ppm of uranium, and can rarely go as high as 20 ppm. In other parts of the world the content can occasionally be higher, up to 300 ppm or so . Let's assume for simplicity that the U content in coal is 1 ppm. Let's assume that the coal is nearly all carbon. Then for each coal atom, there is 1x10^-6 U atom. 4) neutron production: The normal decay mode for U is alpha decay. The spontaneous fission rate is much lower 5) C-14 content: In steady state, we will also have 1.7x10^-22 C-14 decays per year. Since the mean life of C-14 is 8267 years, we would then have 1.4x10^-18 C-14 atoms per atom of coal in steady state. The modern atmospheric ratio of C-14 to total C is about 1x10^-12. Thus, the steady state value for our assumptions is about 1.4x10^-4 percent modern carbon. If we assume 300 ppm U instead of 1 ppm U, we would get about 4x10^-2 percent (0.04%) modern carbon. This value is still pretty small; the RATE coal samples were 3x to 12x larger. So unless the RATE coal samples had 1000 to 4000 ppm of U, I can't see how in-situ production of C-14 from U accounts for their coal data."Science without religion is lame, religion without science is blind." — Albert Einstein I am very astonished that the scientific picture of the real world around me is very deficient. It gives us a lot of factual information, puts all of our experience in a magnificently consistent order, but it is ghastly silent about all and sundry that is really near to our heart, that really matters to us. It cannot tell us a word about red and blue, bitter and sweet, physical pain and physical delight; it knows nothing of beautiful and ugly, good or bad, God and eternity. Science sometimes pretends to answer questions in these domains, but the answers are very often so silly that we are not inclined to take them seriously. — Erwin Schroedinger
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kbertsche Member (Idle past 2162 days) Posts: 1427 From: San Jose, CA, USA Joined: |
bad argument. sorry.
I welcome any corrections that you can give to my argument!
What if the coal were near a vein/deposit of uranium? Your calculations are using just the numbers for the uranium that might be contained in coal.
Your suggestion sounds reasonable to me, but I'm not a geologist. This supposition would be much more solid if someone could find some experimental, observational data to back it up. Anyone?
... But why cannot there be sources of U nearby which are on the order of 1 percent?
Also there is boron-11 that emit neutrons after absorbing alpha particles. This could be a source of neutrons generated from U either within the coal or nearby. How common is boron in coal? Not sure, but I know that it is one of the elements that is found in coal ash that gets people upset. The issue here would be that the production of neutrons is tied to the alpha decay which is many times the rate of spontaneous fission.
Are you sure that you haven't mixed up these details? Do you have any references for the cross sections of an (alpha,n) reaction for B-11? I know that B-10 has a HUGE cross section (thousands of Barns) for the opposite reaction, (n, alpha). Natural boron is about 20% B-10 and 80% B-11. But the (n, alpha) cross section on B-10 is so large that natural boron is commonly used as a neutron absorber in nuclear reactor and particle accelerator development. (I knew a fellow building a small commercial proton accelerator who surrounded it with boxes of commercial borax to act as neutron absorbers.) I don't see how boron helps; any boron in the coal would tend to absorb neutrons and reduce the number available to make C-14 from N-14."Science without religion is lame, religion without science is blind." — Albert Einstein I am very astonished that the scientific picture of the real world around me is very deficient. It gives us a lot of factual information, puts all of our experience in a magnificently consistent order, but it is ghastly silent about all and sundry that is really near to our heart, that really matters to us. It cannot tell us a word about red and blue, bitter and sweet, physical pain and physical delight; it knows nothing of beautiful and ugly, good or bad, God and eternity. Science sometimes pretends to answer questions in these domains, but the answers are very often so silly that we are not inclined to take them seriously. — Erwin Schroedinger
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kbertsche Member (Idle past 2162 days) Posts: 1427 From: San Jose, CA, USA Joined: |
In fact, there are more abundant radioisotopes than those of uranium. Thorium is about 3 times as abundant, IIRC. Not only that, but we should probably be dealing with daughter products more than the uranium itself.
But we need neutrons to create C-14. I don't believe that Th or the U-Th daughter products can emit neutrons.
I think if we just look at the radon flux through coal beds for instance, we might come up with a very different viewpoint of what is happening.
If we could measure the Rn emission, we could get an independent estimate of the U content (and neutron flux) in the vicinity. This could be helpful."Science without religion is lame, religion without science is blind." — Albert Einstein I am very astonished that the scientific picture of the real world around me is very deficient. It gives us a lot of factual information, puts all of our experience in a magnificently consistent order, but it is ghastly silent about all and sundry that is really near to our heart, that really matters to us. It cannot tell us a word about red and blue, bitter and sweet, physical pain and physical delight; it knows nothing of beautiful and ugly, good or bad, God and eternity. Science sometimes pretends to answer questions in these domains, but the answers are very often so silly that we are not inclined to take them seriously. — Erwin Schroedinger
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kbertsche Member (Idle past 2162 days) Posts: 1427 From: San Jose, CA, USA Joined:
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Thanks RAZD.
I wouldn't be surprised if Libby decided, based in the data, that it really WAS in equilibrium, and then became somewhat stubborn in this conclusion. The claim that the atmosphere is in equilibrium is nearly true. If one assumes the Libby half-life and atmospheric equilibrium, I believe the errors over the past 40,000 years are no more than about 15%.I'm looking for that particular paper because the YEC folk I am dealing with insist that Libby stubbornly opposed the notion that the atmosphere wasn't in equilibrium. I've read everything I can get my hands on and of course nothing of the sort is true (the opposite is true in fact). I'm just trying to read his work all the way back to the beginning so I can be knowledgeable. JB
But with modern radiocarbon calibration to tree rings (which Erv Taylor calls a "second radiocarbon revolution"), atmospheric equilibrium is irrelevant. As YEC Gerald Aardsma says:quote: Though Aardsma is a YEC who was formerly on staff for ICR, he understands radiocarbon dating. The common YEC assertions that radiocarbon dating depends on "uniformitarian assumptions" of a constant decay rate and a constant atmospheric concentration are out of date by 40 years."Science without religion is lame, religion without science is blind." — Albert Einstein I am very astonished that the scientific picture of the real world around me is very deficient. It gives us a lot of factual information, puts all of our experience in a magnificently consistent order, but it is ghastly silent about all and sundry that is really near to our heart, that really matters to us. It cannot tell us a word about red and blue, bitter and sweet, physical pain and physical delight; it knows nothing of beautiful and ugly, good or bad, God and eternity. Science sometimes pretends to answer questions in these domains, but the answers are very often so silly that we are not inclined to take them seriously. — Erwin Schroedinger
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kbertsche Member (Idle past 2162 days) Posts: 1427 From: San Jose, CA, USA Joined:
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I have to admit that this just adds to my confusion on this matter.
It doesn't matter whether C-14 is produced by a decay chain or is cosmogenic. The C-14 concentration will build up at the same rate, with the same math, as a short-lived isotope formed from a long-lived parent. This situation absolutely does not apply to C12-C14. C14 is NOT produced by a decay chain, and I find it difficult to believe that Libby thought any such thing. Surely when Libby discussed equilibrium he did not mean secular equilibrium. On what basis could he even have calculated such a thing? What decay is claimed to be producing C-14? In short, there is no secular equilibrium situation for C-14 to be a part of. So when Libby claimed that C-14 was in secular equilibrium, what could he possibly have meant? Was he actually unaware of how C-14 was produced? And when people claim that C-14 is not at equilibrium are they making exactly the same error? The situation will never truly reach equilibrium. But in seven half-lives the level will be within 1% of the equilibrium value. In ten half-lives it will be within 0.1% of the equilibrium value."Science without religion is lame, religion without science is blind." — Albert Einstein I am very astonished that the scientific picture of the real world around me is very deficient. It gives us a lot of factual information, puts all of our experience in a magnificently consistent order, but it is ghastly silent about all and sundry that is really near to our heart, that really matters to us. It cannot tell us a word about red and blue, bitter and sweet, physical pain and physical delight; it knows nothing of beautiful and ugly, good or bad, God and eternity. Science sometimes pretends to answer questions in these domains, but the answers are very often so silly that we are not inclined to take them seriously. — Erwin Schroedinger
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kbertsche Member (Idle past 2162 days) Posts: 1427 From: San Jose, CA, USA Joined: |
It doesn't matter whether C-14 is produced by a decay chain or is cosmogenic. The C-14 concentration will build up at the same rate, with the same math, as a short-lived isotope formed from a long-lived parent.
It's not quite that simple. The calculations work for a constant production rate, but the cosmogenic production of C14 is not constant. And there are other factors, human activity has upset the balance with nuclear testing, and with the release of old carbon from burning fossil fuel."Science without religion is lame, religion without science is blind." — Albert Einstein I am very astonished that the scientific picture of the real world around me is very deficient. It gives us a lot of factual information, puts all of our experience in a magnificently consistent order, but it is ghastly silent about all and sundry that is really near to our heart, that really matters to us. It cannot tell us a word about red and blue, bitter and sweet, physical pain and physical delight; it knows nothing of beautiful and ugly, good or bad, God and eternity. Science sometimes pretends to answer questions in these domains, but the answers are very often so silly that we are not inclined to take them seriously. — Erwin Schroedinger
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kbertsche Member (Idle past 2162 days) Posts: 1427 From: San Jose, CA, USA Joined: |
You are correct that the cosmogenic production rate of C-14 is not constant. However, our atmosphere provides a huge buffer of CO2 which tends to greatly smooth out the variations in C-14 production. Hence one can treat the cosmogenic production rate as nearly constant, at the average production rate.
That's completely wrong. The amount of CO2 in the atmosphere has nothing at all to do with the production rate of C-14 from Nitrogen-14. The large amount of carbon can only buffer the decay rate of C-14. I suppose that this is a good argument that C-14 is generally not in equilibrium. I believe that when Libby and most other radiocarbon experts talk about "equilibrium" they usually mean "equilibrium" the way that I have explained it, that the radiocarbon decay rate is approximately equal to its average production rate."Science without religion is lame, religion without science is blind." — Albert Einstein I am very astonished that the scientific picture of the real world around me is very deficient. It gives us a lot of factual information, puts all of our experience in a magnificently consistent order, but it is ghastly silent about all and sundry that is really near to our heart, that really matters to us. It cannot tell us a word about red and blue, bitter and sweet, physical pain and physical delight; it knows nothing of beautiful and ugly, good or bad, God and eternity. Science sometimes pretends to answer questions in these domains, but the answers are very often so silly that we are not inclined to take them seriously. — Erwin Schroedinger
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kbertsche Member (Idle past 2162 days) Posts: 1427 From: San Jose, CA, USA Joined: |
Whether or not such a calculation is acceptable depends on whether you care about or choose to ignore the inaccuracies such a calculation produces. If you care about 20% errors then you have to parse out that 'nearly'.
But with modern radiocarbon dating, equilibrium is irrelevant. Calibrated dates do not depend on equilibrium. There are no errors of calculation due to assuming equilibrium.
Well here you are just wrong.
By "decay rate" I mean the same thing that is normally meant by the term as used in the radioisotope dating community. The decay rate is the rate at which a radioisotope decays. The decay rate can be expressed as half life, mean life, time constant, or decay constant. The decay rate is constant. It is a function only of the stability of the nucleus. It does not depend on the amount of material or anything else. In fact the amount of C-14 in the atmosphere does affect decay rate. The decay rate of C-14 is proportional to the product of the amount of C-14 and the decay constant of C-14. The decay constant lambda is of course constant, and as you've argued, the amount of variation in the amount of C-14 is swamped by the amount already in the atmosphere. Just what do you mean when you refer to the decay rate? Edited by kbertsche, : No reason given."Science without religion is lame, religion without science is blind." — Albert Einstein I am very astonished that the scientific picture of the real world around me is very deficient. It gives us a lot of factual information, puts all of our experience in a magnificently consistent order, but it is ghastly silent about all and sundry that is really near to our heart, that really matters to us. It cannot tell us a word about red and blue, bitter and sweet, physical pain and physical delight; it knows nothing of beautiful and ugly, good or bad, God and eternity. Science sometimes pretends to answer questions in these domains, but the answers are very often so silly that we are not inclined to take them seriously. — Erwin Schroedinger
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kbertsche Member (Idle past 2162 days) Posts: 1427 From: San Jose, CA, USA Joined: |
By "decay rate" I mean the same thing that is normally meant by the term as used in the radioisotope dating community. The decay rate is the rate at which a radioisotope decays. The decay rate can be expressed as half life, mean life, time constant, or decay constant. The decay rate is constan My reason for asking is that I was pretty sure you were making that mistake. I recommend that you check the definitions. Decay rate means the number of disintegrations over a period of time. The half life, time constant and decay constant are actually constants although some of those things (namely the decay constant) have reciprocal relationships to the half life. But the decay rate depends on how large the sample is. The decay rate is constant per gram of material. But for an amount of material, such as the C-14 in the atmosphere, the rate of removal, which is essentially the decay rate is given by -N * lambda, where lambda is the decay constant and N is the amount. It's also pretty clear that N*lambda is the value that must be in equilibrium with the production rate, which ought to be enough to remove any ambiguity from what I posted. Perhaps a source of confusion is that lambda is sometimes called 'the decay rate constant' because it is the constant factor used to calculate the decay rate. For example, see Thomas Higham (The method):
quote:or Beta Analytic (What is Carbon-14 (14C) Dating? Carbon Dating Definition): quote:or Cook, Southon, and Wadsworth (http://www.tms.org/pubs/journals/JOM/0305/Cook-0305.html) quote: I understand the physics behind the situation at a level approaching your own. Apparently there are a few things about the subject where I know more than you do.
I am willing to discuss principles and concepts with any here who are truly interested in discussion and learning. But I am NOT interested in semantic arguments with folks who arrogantly claim to know more than everyone else."Science without religion is lame, religion without science is blind." — Albert Einstein I am very astonished that the scientific picture of the real world around me is very deficient. It gives us a lot of factual information, puts all of our experience in a magnificently consistent order, but it is ghastly silent about all and sundry that is really near to our heart, that really matters to us. It cannot tell us a word about red and blue, bitter and sweet, physical pain and physical delight; it knows nothing of beautiful and ugly, good or bad, God and eternity. Science sometimes pretends to answer questions in these domains, but the answers are very often so silly that we are not inclined to take them seriously. — Erwin Schroedinger
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kbertsche Member (Idle past 2162 days) Posts: 1427 From: San Jose, CA, USA Joined: |
Back to the thread topic and JB's questions:
I'm looking for that particular paper because the YEC folk I am dealing with insist that Libby stubbornly opposed the notion that the atmosphere wasn't in equilibrium. I've read everything I can get my hands on and of course nothing of the sort is true (the opposite is true in fact). I'm just trying to read his work all the way back to the beginning so I can be knowledgeable.
Have you been able to get a copy of Libby's paper? (I don't have a copy, unfortunately.) JB
Have you looked at Libby's book "Radioactive Dating" (Chicago: University of Chicago Press, 1952, 1955)? Curt Sewell claims that Libby expressed concern in this book that the specific decay rate did not seem to be equal to the specific production rate. (But Sewell's quote from Libby's book does not support his claim very well.) FYI, Dave Matson has looked into some of the YEC non-equilibrium claims. These are similar to the ones that I've heard, that we are only 1/3 of the way to equilibrium, or are 60% out of equilibrium. Matson traces these claims back to Henry Morris and others in the 1960's."Science without religion is lame, religion without science is blind." — Albert Einstein I am very astonished that the scientific picture of the real world around me is very deficient. It gives us a lot of factual information, puts all of our experience in a magnificently consistent order, but it is ghastly silent about all and sundry that is really near to our heart, that really matters to us. It cannot tell us a word about red and blue, bitter and sweet, physical pain and physical delight; it knows nothing of beautiful and ugly, good or bad, God and eternity. Science sometimes pretends to answer questions in these domains, but the answers are very often so silly that we are not inclined to take them seriously. — Erwin Schroedinger
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kbertsche Member (Idle past 2162 days) Posts: 1427 From: San Jose, CA, USA Joined:
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You might also find some useful comments on equilibrium from Libby's Nobel lecture:
Willard Libby writes:
To return to radiocarbon dating - knowing that there are about 2 neutrons formed per square centimeter per second, each of which forms a carbon-14 atom, and assuming that the cosmic rays have been bombarding the atmosphere for a very long time in terms of the lifetime of carbon-14 (carbon-14 has a half-life of about 5,600 years) - we can see that a steady-state condition should have been established, in which the rate of formation of carbon-14 would be equal to the rate at which it disappears to reform nitrogen-14. This allows us to calculate quantitatively how much carbon-14 should exist on earth (see Fig. 1); and since the 2 atoms per second per cm2 go into a mixing reservoir with about 8.5 grams of carbon per cm2, this gives an expected specific activity of living matter of 2.0/8.5 disintegrations per second per gram of carbon. The mixing reservoir consists not only of living matter which dilutes the radiocarbon, but of the dissolved carbonaceous material in the oceans which can exchange carbon with the atmospheric carbon dioxide and thus dilute it. In fact, the ocean is the larger part of the diluting carbon reservoir (see Table I). For each square centimeter of the earth’s surface, there are about 7.25 grams of carbon dissolved in the ocean in the form of carbonate, bicarbonate, and carbonic acid, and the biosphere itself contains about 0.33 gram per square centimeter of surface. Adding all the elements of the reservoir, we get a total of 8.5 grams of diluting carbon per cm2, and the 2.0 carbon-14 atoms disintegrating every second should be contained in 8.5 grams of carbon. Thus, the specific activity of living carbon should be that number. We find this to be the actual value observed to within about 10 percent (see Table 2). Of course, the times for mixing of all parts of the reservoir must be short compared to the average lifetime of radiocarbon, 8,000 years. The time for mixing of the oceans is the longest, about 1,000 years on the average. This is interesting, for it means the following : The present intensity of the cosmic radiation (unless there have been canceling errors in our calculations) corresponds to the average intensity over the last 8,000 years, the average life of carbon-14. It says also that the ocean is mixed nearly perfectly to its bottom depths in 8,000 years. This we know because we included all of the dissolved carbon in the sea. Also, direct measurement of the carbonate and bicarbonate in deep ocean water confirms this. These conclusions could be false if errors in the very different quantities - the intensity of the cosmic rays and the mixing rate and depths of the oceans - should happen just to cancel one another. Being so unrelated, we believe this to be very unlikely and conclude that the agreement between the predicted and observed assays is encouraging evidence that the cosmic rays have indeed remained constant in intensity over many thousands of years and that the mixing time, volume, and composition of the oceans have not changed either.
"Science without religion is lame, religion without science is blind." — Albert Einstein I am very astonished that the scientific picture of the real world around me is very deficient. It gives us a lot of factual information, puts all of our experience in a magnificently consistent order, but it is ghastly silent about all and sundry that is really near to our heart, that really matters to us. It cannot tell us a word about red and blue, bitter and sweet, physical pain and physical delight; it knows nothing of beautiful and ugly, good or bad, God and eternity. Science sometimes pretends to answer questions in these domains, but the answers are very often so silly that we are not inclined to take them seriously. — Erwin Schroedinger
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