Earth science curriculum tailored to fit wavering fundamentalists

Yep that's the claim I have seen before. Because Libby said it then it must be true ...Here's some information on equilibrium, where I picked the case that would come closest to 14C decay because the production is relatively constant:

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Radioactive Equilibrium
Radionuclide Has a Much Longer Half-Life

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When the half-life of the original radionuclide is much longer than the half-life of the decay product, the decay product generates radiation more quickly. Within about 7 half lives of the decay product, their activities are equal, and the amount of radiation (activity) is doubled. Beyond this point, the decay product decays at the same rate it is produced a state called "secular equilibrium.

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And 7 times 5568 = ~38,976 years. (Change that to 5730 and you get ~40,110 years ...)But now we know that 14C production is not steady, and the variation is enough to cause the disequilibrium we see.Another interesting take is this (from John Mackay, Creation Research):

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CARBON 14 dating proves things are too old for Genesis to be true. What’s your argument against it?

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Limitations

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... However, if the level of C14 in the atmosphere has not reached equilibrium there is a serious problem.

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To put it in technical terms, according to radioactivity expert Curt Sewell: The Specific Production Rate (SPR) of C14 is known to be 18.8 atoms per gram of total carbon per minute. The Specific Decay Rate (SDR) is known to be only 16.1 + / — 0.5 disintegrations per gram per minute. (see article by Sewell here)

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What’s the significance?

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We put this to former Los Alamos Nuclear Physicist Dr Tom Hayward and asked him to calculate how long it would take to build C14 up to its current level starting from zero, and to graph the results for us. His results and graphs are as follows:

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1: Time for formation rate to be in equilibrium with decay rate is 30,000years.

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2: Time needed to reach current position of disequilibrium is between 13 and 16,000 years, assuming rates of C14 formation/decay are the same today as they have always been.

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Notice the palming of the pea to extend the level down to 15.3 disintegrations per gram per minute in order to get the theoretical age from constant 14C production down to ~13,000 years ... and that even then this is still significantly older that the standard ~6500 YEC age by a factor of 2.And the logic is :: gosh it's not 16,000 years old, so therefore it must be 6500 years old?It gets more amusing as he explains old 14C dates by assuming that the preflood 14C was minimal:

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Radioactive carbon may not rate a mention in Genesis, but the Bible does tell us that when God finished creating the world it was very good. As radioactive carbon causes genetic mutations, it is not very good, so the air Adam and Eve breathed in and the plant food they ate did not contain it. It is most likely that the combination of the waters above (see Genesis 1:6-9) and seemingly stronger magnetic field would have kept out the radiation that constantly makes C14 in today’s atmosphere. However, after Noah’s Flood the protection of the waters above was removed, and the magnetic field is continuing to decay even as you read. Therefore radioactive carbon is building up in the atmosphere, and will continue to do so should the earth endure to 30,000 yrs of age.

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So now we must have 16,000 years back to the flood (circa 4500 years ago?) to reach todays atmospheric levels ... It would be interesting to take the 14C atmospheric levels known from the tree ring ages and integrate what the current atmosphere level should be.ExperimentYou can discuss this aspect with an experiment. One of the ways to visually model radioactive decay is with a leaky bucket ... lets start with this image:

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Carbon-14 Dating Confirms Earth is Young

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(Of course we know the level is NOT constant, but this show that the more 14C you have (inflow) the more decay you have (outflow), and when decay = production you would have equilibrium.)Use a rain barrel and meter the flow through a drain hole, use constant inflow at several different rates and see how full the barrel gets. Then change it to half on and half off inflow and see how that affects the output.The output is ∝ depth, so this would model the change in decay with atmospheric concentration. You can show what equilibrium is, that it is different for different inflow rates, and that it tends to average fluctuations -- the fuller the barrel is the less the effect of variation has. Note that Sewel states:

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... No one knows this answer, so they assume that the atmosphere has always been like it was in 1950. But this is known to be wrong!

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The Specific Production Rate (SPR) of 14C is known to be 18.8 atoms per gram of total carbon per minute. The Specific Decay Rate (SDR) is known to be only 16.1 + / - 0.5 disintegrations per gram per minute. The difference between these two numbers shows that the buildup in the biosphere hasn't had time to catch up with production in the stratosphere. In other words, the earth's atmosphere must be less than some fifty thousand years old! This, in itself, is a strong evidence of creationist claims. But the 14C establishment's response is that it's merely a problem not yet solved.

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Is "atoms per gram of total carbon per minute" the same as "disintegrations per gram per minute" - they would appear to be: one 14C atom produce from 14N + cosmic ray and one atom 14N produced from 14C with beta decay.You will note that sources for these numbers are not given. Is 18.8 the level in 1950? today?Carbon-14 - Wikipedia

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As of 2008, the rate of carbon-14 production was poorly known — while the reaction can be modelled or the current concentrations and the global carbon budget can be used to backtrack, attempts to directly measure the production rate had not agreed with these models very well. Production rates vary because of changes to the cosmic ray flux incident, such as supernovae, and due to variations in the Earth's magnetic field. The latter can create significant variations in carbon-14 production rates, although the changes of the carbon cycle can make these effects difficult to tease out.[10]

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The natural atmospheric yield of carbon-14 has been estimated to be about 22 000 atoms 14C per meter square of the surface of the earth per second, resulting in the global production rate of about 1 PBq/a.[11] Another estimate of the average production rate[12] gives a value of 20 500 atoms m−2s−1. Occasional spikes are possible; for example, there is evidence for an unusual 10-fold increase of the production rate in AD 774—775.[13]

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(Note they also talk about other sources)Curiously I have difficulty translating "atoms/m^2/s^1" to "atoms per gram of total carbon per minute" -- might want to talk to Los Alamos Nuclear Physicist Dr Tom Hayward (or others)EnjoyEdited by RAZD, : clrty

I have to admit that this just adds to my confusion on this matter.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?Edited by NoNukes, : No reason given.

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.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.

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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.

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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.

Let's explore that idea of the 'same math' and its relevance to the question I have asked.Assuming that C-14 builds up from a decay chain from which the top of the decay chain is not being replenished, but is long lived compared to C-14. In that case, one could calculate a secular equilibrium value and then make statements about whether the current amount of C-14 is or is not at that value. That's the case for example for the U-Th decay chain, right?Now, let's consider the actual case where C-14 is produced cosmogenically. In that case, the 'equilbrium value' varies cosmogenically. In that case, to say that C-14 is or is not in equilibrium is to say that it is the correct proportion based on the current comsogenic rate? The cosmogenic rate depends not only on the amount of N-14 in the atmosphere, but also the neutron flux, with the latter depending on stuff like earth's magnetic field, perhaps the sun, and the perhaps the occurrence of super nova's that happened in the remote past.I disagree that the math is the same, except for the principle that equilibrium occurs when the rate of production is equal to the rate of C-14 decay. In the cosmo case described above, there is no single equilibrium value to 'oscillate around' as RAZD described. The equilibrium value itself varies. And given that value, the C-14 may or many not be in equilibrium.I'd appreciate being pointed out where my logic is incorrect, but I'm pretty sure that I have pointed out an issue with the discussion here. I don't believe the math does turn out to be exactly the same.

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.Edited by NoNukes, : No reason given.

Maybe I was unclear, or you misunderstood me? The atmosphere greatly smooths out the effects of C-14 production variations. I.E. it smooths out changes in the atmospheric concentration of C-14 and makes the atmospheric concentration of C-14 nearly constant. Even if the production rate were to change significantly, the atmospheric concentration would not change very much. (Note that the atmosphere does NOT affect or "buffer" the decay rate.)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.

I think that we can agree that, as a practical matter, the atmosphere is close enough to equilibrium that radiocarbon dating will produce reasonable results without correcting for the differences.However, corrections are needed - to account for historic variations as well - if we want really accurate dates. And the argument that the Earth must be young because the atmosphere is not in equilibrium is just plain wrong.

Perhaps I misunderstood you, but you helped. To wit: 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'. It is not clear to me what they meant. I'm asking what Libby meant and what the non-experts meant when they had their dispute with Libby. Well here you are just wrong.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 NoNukes, : No reason given.

There is of course no decay producing 14C in our atmosphere. What I was looking at was the situation where a radioactive isotope is produced at an assumed constant rate, and the lower curve would match that situation.We know that production is not constant but varies over a (iirc) 19 year cycle and some longer cycles due to variations in solar activity and variations in the earth magnetic field.We also know that a lot of old 12C has been released into the atmosphere from fossil fuel use since the dawn of the coal age, which would depress the current concentration level of 14C/12C in the atmosphere.And we know that current production of 14C is above pre-atomic age numbers.So if you skew which data you use with this situation you can have a current concentration level below what an assumed constant level high input production should give for equilibrium. If you assume a constant production and a decay amount ∝ to the concentration level then you will get an exponential curve.Just like you will get from a rain barrel with a hole in the bottom and constant inflow from a hose.EnjoyEdited by RAZD, : clrty

Except that the assumption of constant production rate is incorrect. And, as you have indicated the assumption does not account for the depression of C-14 by the release of old carbon. You've only begun to tell the story here. The variations in the earth's magnetic field are not periodic.What is important is that over the range of time, the amount of C-14 in the atmosphere, when averaged over quite some time, has not fluctuated by huge amounts over 50,000 years. But even over 10,000 year periods, the amount has varied enough to need correcting. My question is simply what definition of equilibrium did Libby argue for and was he correct or incorrect. Why would I want to skew the data? The truth is that even if you use real data, the production rate of C-14 in the atmosphere often does not match the current rate of depletion. In fact, given the long half life of C-14 compared to say, the solar cycle, the product rate and the removal rate may be different more often than not.Henry Morris (and Hovind) argued that the earth could not be old because equilibrium would have been reached long ago. Morris's argument is wrong not because equilibrium has been reached, but because there are good reasons why equilibrium does not exist. Hovind of course is a convicted liar and felon.Edited by NoNukes, : No reason given.

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. 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.Edited by kbertsche, : No reason given.

Nonetheless, given that this was a controversy about equilibrium in Libby's time that I want to understand, I am still asking about equilibrium. I understand the calibration of dates. Those things have been expounded on here at length in this very thread. I am not challenging the concept of C-14 dating.Telling me that equilibrium is irrelevant for dating is not helpful here. It is also the case the expounding on the basic physics of nuclear decay and glossing over variations by talking about 'average rates', might be reasonable in another context. But that is not helpful to me either. 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. 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.http://formulas.tutorvista.com/...rate-of-decay-formula.html

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"The rate of decay is the number of nuclei that decay each second. It is measured in becquerel(Bq) where 1Bq = 1 decay/s."

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Radioactive Decay Rates - Chemistry LibreTexts

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Decay Rates
Due to the smaller size of the nucleus compared to the atom and the enormity of electromagnetic forces, it is impossible to predict radioactive decay. The atomic nucleus which is in the center of the atom is buffered by surrounding electrons and external conditions. Because of this, the study of decay is independent of the element's environment. In other words, the decay rate is independent of an element's physical state such as surrounding temperature and pressure. For a given element, the decay or disintegration rate is proportional to the number of atoms and the activity measured in terms of atoms per unit time. If "A" represents the disintegration rate and "N" is number of radioactive atoms, then the direct relationship between them can be shown as below:

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A∝N
or mathematically speaking

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A=λN
where

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A is the Total activity and is the number of decays per unit time of a radioactive sample.
N is the total number of particles in the sample.
λ is the constant of proportionality or decay constant.

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Hope this helps...Edited by NoNukes, : No reason given.Edited by NoNukes, : Provide references

Exactly, so when creationists start talking about this we know they are starting from an invalid position. Like I said it would be interesting to plot our the 14C levels versus time from the tree ring data to show that it is not a smooth curve as these articles (note they were from two creationist sites, except the secular decay curve I posted). Neither is the cosmic ray strictly speaking. We do know that sun activity has some periodic behavior, and it shows up like clock ticks on the tree ring data. And we know these ancient levels from artifacts of known age, like tree rings, Without reading the paper I don't have a clue what he said, all I am doing is pushing back on the creationist claims, where it doesn't really matter what Libby said as equilibrium cannot be expected from a variable input.What I do know is that we don't really appear to have a good idea of the rate of production or it's transportation to surface organisms: I found a number of papers with quite different results. We don't. The creationists do, and it is SOP for many of them to do so. Indeed. Sometimes more, sometimes less (once you correct for fossil fuel 12C and atomic reaction 14C, etc). Morris is wrong because the earth is easily countably older (Age Correlations and An Old Earth, Version 2 No 1) than this purported age to equilibrium, as documented by mountains of data. Hovind is a used-car\snake-oil salesman.It's typical creationist hogwash, down to the appeal to old science\authority and misrepresentation of facts.Enjoy