Difference between revisions of "Talk:Carbon dating"

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Other isotopes with longer half-lives can also be used to date objects.  However, each method has its own drawbacks.
 
Other isotopes with longer half-lives can also be used to date objects.  However, each method has its own drawbacks.
  
[[Young Earth Creationism|Young-Earth creationists]] point out that the atmospheric ratio of carbon-12 to carbon-14 would have been affected by the [[Great Flood|global flood]], as the flood buried massive quantities of living things,<ref>Batten 2007, p. 71.</ref> thus invalidating dating results from that era as secular science does not allow for this.  As such dating results ''presume'' that there was no flood, the resulting dates are not ''proof'' that there was no flood, as anti-creationists often charge.
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[[Young Earth Creationism|Young-Earth creationists]] point out that the atmospheric ratio of carbon-12 to carbon-14 would have been affected by the [[Great Flood|global flood]], as the flood buried massive quantities of living things,<nowiki><ref>Batten 2007, p. 71.</ref></nowiki> thus invalidating dating results from that era as secular science does not allow for this.  As such dating results ''presume'' that there was no flood, the resulting dates are not ''proof'' that there was no flood, as anti-creationists often charge.
  
 
: The entire thing is important...-'''<font color="#007FFF">Ames</font><font color="#FF0000">G</font>'''<sub>[http://www.conservapedia.com/User_talk:AmesG yo!]</sub> 11:48, 6 May 2007 (EDT)
 
: The entire thing is important...-'''<font color="#007FFF">Ames</font><font color="#FF0000">G</font>'''<sub>[http://www.conservapedia.com/User_talk:AmesG yo!]</sub> 11:48, 6 May 2007 (EDT)
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* Quarternary Dating Methods, by M. Walker (Wiley & Sons, 2005).
 
* Quarternary Dating Methods, by M. Walker (Wiley & Sons, 2005).
 
*Isotopes: Principles and Applications, by G. Faure and T. Mensing (Wiley & Sons, 2005).
 
*Isotopes: Principles and Applications, by G. Faure and T. Mensing (Wiley & Sons, 2005).
[[Category:Earth science]]
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* Batten, Don et. al., [http://www.creationontheweb.com/images/pdfs/cabook/chapter4.pdf ''What about carbon dating?''], Chapter 4 of ''The Creation Answers Book'', Creation Book Publishers, 2007, ISBN 978-0949906625.
 
* Batten, Don et. al., [http://www.creationontheweb.com/images/pdfs/cabook/chapter4.pdf ''What about carbon dating?''], Chapter 4 of ''The Creation Answers Book'', Creation Book Publishers, 2007, ISBN 978-0949906625.
  
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How do you explain the fact that carbon dating methods were verified through many other methods of dating?  When Libby developed the method he checked his results using verified historical records pertaining to the life of Zoser during the thrid dynasty.  Carbon dating has also been proven effective through comparing results from other unrelated aging methods such as U/T dating, Optically Stimulated Luminescence (OSL), Thermoluminescence, Electron Spin Resonance, Dendrochronology, and Potassium-Argon dating.  I have personally tested the age of a buried hearth pit using carbon dating and OSL, and the results were he same. [[User:Prof0705|Prof0705]] 16:15, 13 May 2007 (EDT)
 
How do you explain the fact that carbon dating methods were verified through many other methods of dating?  When Libby developed the method he checked his results using verified historical records pertaining to the life of Zoser during the thrid dynasty.  Carbon dating has also been proven effective through comparing results from other unrelated aging methods such as U/T dating, Optically Stimulated Luminescence (OSL), Thermoluminescence, Electron Spin Resonance, Dendrochronology, and Potassium-Argon dating.  I have personally tested the age of a buried hearth pit using carbon dating and OSL, and the results were he same. [[User:Prof0705|Prof0705]] 16:15, 13 May 2007 (EDT)
  
== Headline text ==
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== Poor "reference" ==
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Reference stated as support for the "older than 50,000 years, carbon-dating is bad" is  [http://www.talkorigins.org/indexcc/CD/CD011.html]
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If you review that posting, it's sourced from someone's comment - not really good science. I think someone needs to volunteer to research the original Faure text on geochemistry
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== Inability to date carbonate rocks -- false? ==
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"Additional anomalous results from carbon dating, which reinforce its limitations, include the inability to date carbonate rocks, which by confound the science behind the dating technique."
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I don't want to remove the statement, in case someone has another reference, but in [http://www.arrhenius.ucsd.edu/pub/Precambrian.pdf This report] (watch out -- it's HUGE) clearly shows a carbon-dating experiment performed on carbonate materials. "We determined the carbon isotope ratio of carbonates on ground powders... by reacting them with concentrated H3PO4... and collecting the evolved CO2.... The evolved and frozen CO2 [was]... transferred to an Isogas precision isotope ratio mass spectrometer (PRISM) for isotopic determination. Error bars of measurements are 0.1‰" (page 336). Am I missing somehthing, or can I remove the statement? [[User:HelpJazz|Help]][[User talk:HelpJazz|Jazz]] 21:07, 5 January 2008 (EST)
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:Ok nobody is responding still, so I'll give 24 hours then remove the statement. [[User:HelpJazz|Help]][[User talk:HelpJazz|Jazz]] 11:43, 26 January 2008 (EST)
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:: I'll look into this.  Give me a day or so.  Thanks.--[[User:Aschlafly|Aschlafly]] 13:49, 26 January 2008 (EST)
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:::Alright. I'm sure there's something I'm missing, but I can't figure out what. [[User:HelpJazz|Help]][[User talk:HelpJazz|Jazz]] 16:01, 26 January 2008 (EST)
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::::Have you had time to take a look at it yet? [[User:HelpJazz|Help]][[User talk:HelpJazz|Jazz]] 16:48, 28 January 2008 (EST)
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== Removal of Information ==
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Why is information being removed from the content page here?--[[User:Aschlafly|Aschlafly]] 11:04, 21 January 2008 (EST)
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:The part about carbonate rocks I addressed two weeks ago (see the talk section directly above this one) and I thought I had waited sufficient time.
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:The other part I removed because the exact same information is presented in the section below, so I didn't think we needed to say the exact same thing twice. [[User:HelpJazz|Help]][[User talk:HelpJazz|Jazz]] 16:10, 21 January 2008 (EST)
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::We certainly don't need to say anything twice, but didn't you remove this essential paragraph:
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:The rate of decay of 14C is such that 50% of the 14C in the sample will decay in 5730 years ... For this reason, scientists do not generally attempt to carbon date material that is believed to be older than about 50,000-60,000 years old.--[[User:Aschlafly|Aschlafly]] 16:35, 21 January 2008 (EST)
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:: P.S. I waited also before reverting, by posting the first message above in this new section.--[[User:Aschlafly|Aschlafly]] 16:37, 21 January 2008 (EST)
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:::I did, because I thought that what was written later said the same thing:
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::::"Since the half-life of 14C is only 5715 years, after 50,000 years only about 1/500th of the 14C remains - and since even initially it is only present as a minute proportion of the whole (0.0000000001% of all Carbon atoms), measuring the exact quantity present with precision enough to be of use for dating purposes is extremely difficult. For this reason, scientists do not generally attempt to carbon date material that is believed to be older than about 50,000-60,000 years old. However, isotopes with longer half-lives may be used."
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:::Many of the phrases are the same and it looks like they were written using the same source.
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:::After I edited this morning I had class till 4, so I wasn't able to respond to the talk page in time. [[User:HelpJazz|Help]][[User talk:HelpJazz|Jazz]] 16:46, 21 January 2008 (EST)
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:::: OK, you're right, but the redundancy near the end is the one to remove, which I've done.  Thanks.--[[User:Aschlafly|Aschlafly]] 17:06, 21 January 2008 (EST)
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:::::Thanks. I thought it was better to remove the first paragraph, but it doesn't really matter eaither way.
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:::::What about the statement "Additional anomalous results from carbon dating, which reinforce its limitations, include the inability to date carbonate rocks, which confound the science behind the dating technique"? As I mentioned in the section above, scientists ''were'' able to date carbonate rocks. This origonally had a <nowiki>{{fact}}</nowiki> tag, and when I went to find a reference which shows that this statement is true, it turns out I couldn't, but I could find a reference which directly refutes it. [[User:HelpJazz|Help]][[User talk:HelpJazz|Jazz]] 17:22, 21 January 2008 (EST)
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== Calibration, Variable Rate of Intake & Atmospheric variability ==
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As I am sure the poster is aware of, this phenomenon is well-known and documented. However, I have seen this phenomenon used to cast aspersions on the effectiveness of radiocarbon dating. Please see the wealth of information on the topic of carbon intake and reservoir correction available online. I'm not sure what sites pass as credible here, so I will only offer the suggestion to search for "carbon reservoir correction" on your favorite engine. I don't want to violate the 90/10 rule, but I wanted to get some discussion on this before attempting to edit the page. Thanks, -- [[User:CWood|CWood]] 11:31, 2 January 2009 (EST)
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: What exactly in the article do you think needs changing?  [[User:Philip J. Rayment|Philip J. Rayment]] 19:04, 2 January 2009 (EST)
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I don't understand the point of mentioning these phenomena without also explaining the methods of accounting for them. So to answer your question, I believe an addition needs to be made explaining how and why intake rates vary and how and how and why they are corrected/calibrated. I understand that the point of the article is in fact to cast aspersion on radiocarbon dating, but I would not endorse doing so in a manner that is so easily controvertible by a quick google search. [[User:CWood|CWood]] 11:54, 13 January 2009 (EST)
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: The article already touches on your points, and doesn't really say a lot about the phenomena otherwise, but I guess that the article could do with some expansion in that regard.
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: The point of the article is to ''describe'' carbon dating, including its limitations.  I believe that it does that reasonably well.
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: [[User:Philip J. Rayment|Philip J. Rayment]] 04:06, 14 January 2009 (EST)
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I agree that the article describes carbon dating reasonably well and I understand that the target is a high school level audience. My point is that by not explaining how scientists attempt to cover the limitations of carbon dating Conservapedians highlighting these limitations may be caught off guard by the introduction of an unknown resource, for instance, reservoir correction tables. Conservapedian: "Carbon dating is limited by factors such as variable rate of intake." Liberal: "Not if you use reservoir correction." Conservapedian:"???" If you like, I will come up with something for your review.[[User:CWood|CWood]] 10:50, 15 January 2009 (EST)
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:: Please do.  [[User:Philip J. Rayment|Philip J. Rayment]] 16:58, 15 January 2009 (EST)
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== Don't censor info ==
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Please add or clarify, but don't [[censor]] info here.--[[User:Aschlafly|Andy Schlafly]] 23:06, 30 April 2009 (EDT)

Latest revision as of 02:36, June 3, 2009

Huge errors on this page

Firstly, there is an claim that carbon dating had wrongly measured the age of some carbonate rocks, oil etc. Ofc it has, because no one in their right minds and knowing even the basics of carbon dating would try to measure those with this method... Offcourse the result is wrong, it's like saying one was trying to measure weight with measuring tape. The whole concept of giving false measurements as a "proof" that the method dosen't work is ridiculous. Who knows how many measuring errors has happened with measuring tape, but no one is claimin that because person "A" measured the lenght of an tree wrong using a measuring tape, that the measuring tapes arent reliable. Im deleting that whole section. Timppeli 10:47, 5 May 2007 (EDT)

This is factual and informative information. Why censor it? The only reason that "no one in their [sic] right minds ... would try to measure those with this method" is because of significant limitations in carbon dating, which is precisely the point. The math alone does not predict that dating rocks and oil should be as unreliable as the results show.--Aschlafly 11:01, 5 May 2007 (EDT)
So you really think there should be an collection of wrong results when trying to measure weight with measuring tape on the pages descriping the measuring tape? Just to prove that the measuring tape is limited on measuring the lenght? You can't measure things such as rocks, oil etc with carbon dating, from the basic reason that the carbon in it is from petroleum. So no one who knows anything about carbon dating would never even try that. And what do you have to say about the general measuring errors? Do you really think that we should now start to post diffrent wrong reasult people have gotten when they where using a volt meter, measuring tape or scales? That makes no sense at all, as said before, it would be ridiculous and would really like to hear why we should do this. Timppeli 11:20, 5 May 2007 (EDT)

Changing decay rates

Further corrections i would like to make are allso removing the following sentences: "First, it is impossible to prove scientifically whether the rate of decay of C-14 has remained constant over hundreds or thousands of years. Some scientists have suggested, based on experimental observations, that the laws of physics do change over time." Indeed, for this to happen laws of physics would have needed to change. And to claim that... Well, im speechles, who exactly is claiming that laws of physics have changed so dramatically during these few years and based on what experiments? Firstly, for it to be any help for the young earth creationists, it would have needed to happen during the last 10 000 years. And the laws of physics to change so much that it would change the half time of C-14 atom... Oh boy. I see no place for claim like this on encyclopedia. There is no evidence of anything like this ever happening, and even the idea of this is so strange to modern science that it's once again just absurd to offer that as an excuse for considering carbon dating not to be valid. If this excuse is accepted here, it can be used on every other scientific article here. They all rely on the fact that laws of physics arent changing around. Timppeli 11:33, 5 May 2007 (EDT)

You're "speechless" about a position of Nobel Laureate Paul Dirac and many physicists today??? Maybe what you meant to say is that you've never heard this. OK, most people (including physics majors) don't hear about this. But, please, let's be at least a little open-minded. I've updated the entry.--Aschlafly 12:36, 5 May 2007 (EDT)
First i would like to quote myself: "Well, im speechles, who exactly is claiming that laws of physics have changed so dramatically during these few years and based on what experiments?" You are claiming that Nobel Laurete Paul Dirac claimed so? It has been long known that for example at the time of the big bang, when scientists presume that the laws of physics where allso born, there might have been some changes. But the key here is that for some one to claim that the laws of physics would have changed so much on earth in so reasent history that the halftime of C-14 atom would have been cut down to 1/5th or something around that is just beyond what any scientist would ever claim. It would mean catastroph to other things here. And if claim like that would be accepted here to undermine the Carbon dating, it could, as said earlyer be used to undermine any scientific findings. Timppeli 13:01, 5 May 2007 (EDT)
You've gone from being "speechless" to saying "it has long [been] known." I'm only interested in an open-minded discussion here. If your mind is made up, and you'll treat anything contrary to your opinion with derision, then this is not productive for you or me. We're both better off working on other entries.
If the C-14 decay rate varies proportionately with the age of the universe, and if that age is, say 5,000 years rather than 10 billion years, then obviously the C-14 decay rate could have been many orders of magnitude larger a thousand years ago.--Aschlafly 13:51, 5 May 2007 (EDT)
It would offcourse help, if one would read why i was speechless, ill quote myself the thirth time: "im speechles, who exactly is claiming that laws of physics have changed so dramatically during these few years and based on what experiments?" But i do think you allready read that, and are just trying not to answer the questions itself. Those questions being. If something like that would have happened in the last 10 000 years, how would anything have survived it? If this is valid argument here, why can't it be used to question everything else in science? Timppeli 14:39, 5 May 2007 (EDT)
There is a circularity in your line of reasoning. You concede the decay rates may have changed, but implicity use the current decay rate to estimate the age of the universe.
Once one concedes that the decay rates may be declining, as one must, then the rates cannot be used to infer the age of the universe. If the universe is 5000 years old, then the decay rate first declined rapidly thousands of years ago. The half-life may have only been 100 years at the time of Christ. I don't see how such a half-life would make any difference to the sustenance of life.--Aschlafly 15:24, 5 May 2007 (EDT)
First off, there is no evidence that decay rates would be declining, as said, that would brake the laws of physics as we know them. Some scientist have speculated that in some special circustamses, like during the very first moments of Big bang those laws might have been under a change, other than that, its all highly speculative talk around fine-structure constant and the changing of the four fundamental forces gravity, electromagnetism, and the strong and weak nuclear forces. None of this has ever been proven to happen and for it to happen in a scale that would change the decay rates enough to make earth 6000 years old... One thing tho is "sure" if that would have happened, and the half time of C-14 had changed enought that it would make any diffrence in age measurements, it would have caused catastrohic consequenses for all life on earth. Mayby even for the whole universe. Simple reason for this is that you cant only change the half time of C-14 it would be more wide spread. This kind of change in laws of physics would make the existing unstable nucleids less stable, and will also make currently stable nucleids unstable. Which would be very very very bad thing. Timppeli 15:54, 5 May 2007 (EDT)

While i remember, i would like to allso point out that the discussion about the "wrongly measured" Carbon rock/oil samples has no conclusion yet. If there is nothing you would like to add to it, i really think those examples should be removed on the basis off what i said on the discussion at the top of the page. Timppeli 16:05, 5 May 2007 (EDT)

For decay rates to change, you'd have to drastically change some of the laws of physics and/or the rest mass of several types of subatomic particles, if this were to happen, chances are entire solar systems will disintegrate and some chemical compounds would not be stable anymore, it is likely something as complicated as carbon based live would die: meaning ALL carbon based life in the universe.

Dirac's ideas about gravitation are highly speculative, highly criticized and deal only with small changes over billions of years, so minute they wouldn't even be detectable over the course of 60,000 years.

Speculation about changing laws of physics are a desperate attempt at creating confusion among those who have accepted evolution to be true. They were inserted here by the same person who argued that there was no way to figure out the CO2 concentrations in the atmosphere over hundreds of thousands of years (there are, and carbon dating is limited to 60,000 years anyway) in an attempt to discredit carbon dating.

Middle Man

That's really an answer here? Changing laws of physics? C'mon.... Will gravity be back tomorrow? I sure hope so. Flippin 16:08, 5 May 2007 (EDT)

the 50,000 year mark

The sentence "For this reason, scientists do not generally attempt to carbon date material that is believed to be older than about 50,000-60,000 years old" is factually incorrect. After 50,000 years carbon-14 would have undergone over 8 half-lives and essentially there rate of change has reached a screeching halt. It is the result of both the small amout of carbon-14 and the length of the half-life that prevent dating back to 50,000 years. Sterile 13:59, 5 May 2007 (EDT) This was addressed in the time I wrote the comment.

Creationwiki

I notice that one of the references used to support some of the stronger claims on this page is Creationwiki. Is that really a good source? Does it really belong here? --Reginod 15:24, 5 May 2007 (EDT)

Well, where else can you get references in support of creationism?

Middle Man

Feel free to find more neutral sites. I'll do it myself eventually. Nothing there is controversial. The first criticism of it, in fact, was that it was too obvious to include.
As to the other comments above, they are criticizing logic more than anything. Yes, many physicists (including Dirac) feel (have felt) that the laws of physics are not invariant over time. I'll find more cites but instead of distracting me on the talk page, you could find sites too. Someone said that life couldn't function unless C-14's half-life is constant. Really, do you think we need a 5000-year half life of C-14 to have life? None can exist without that fundamental decay rate? Physicists think other constants that are more fundamental have changed, so I don't attach much significance to a claim that C-14's decay rate cannot possibly change.--Aschlafly 21:17, 5 May 2007 (EDT)


I explained everything didn't I? Decay rates depend on rest-masses of subatomic particles among other things, these same rest-masses also determine which atomic particles and which chemical bonds can exist: imagine what would happen if all the nuclei in the universe would disintegrate...

I also explained Dirac's ideas were about minute changes over billions of years.

Do I have to explain myself again, or should I let a lawyer lecture me about Dirac's theories?

Middle Man

Yeah, you do have to lecture me if you think the laws of physics, including the decay rate for C-14, has never changed. And after you lecture me, lecture every physicist who ever studied the Big Bang, and all their students. And then lecture every one who has ever studied Karl Popper and understands what science is. And then nominate yourself for the Nobel Prize!--Aschlafly 00:01, 6 May 2007 (EDT)
Andy, the source you cites suggests that one law of physics has changed. However, Middle Man et al are right about how sweeping a change on the half life of carbon would be. In science, every piece interlocks with the other, such that a change to one implies a great change to the other. SO, changing the half-life of carbon to change would imply a change in the base atomic structure of carbon, which would prevent the ability of carbon to bond as readily as it does, which would destroy the reason that makes carbon the inherent building block of life. You can't just say "the laws of physics changed" without realizing the full extent of what you're saying - you're saying that the very nature of life, and the very structure of atoms, has changed within the past 6000 years. And I'm sure you realize that Karl Popper cuts against you - your little "theory" is unfalsifiable, aside from being absurd for the reasons stated above.-AmesGyo! 11:38, 6 May 2007 (EDT)
I implemented those changes, since the challenges had been posed & unanswered in a while.-AmesGyo! 11:48, 6 May 2007 (EDT)
It was my rebuttal that went unanswered.
There is no reason or evidence to think that life cannot function with a shorter half-life for C-14. Your comments reflect nothing more than a view that the world has to be a way that you believe it to be. More open-mindedness is expected of editors on this site. Yes, C-14 half's life may have been different, just as scientists are suggesting that many other aspects of the laws of physics were also different.--Aschlafly 12:02, 6 May 2007 (EDT)

Andy, you misunderstand. For carbon's half life isn't just a variable that gets changed like you change the value of X in algebra. Rather, it depends on subatomic masses of particles. So, to change C-14's half life, you'd have to change subatomic mass numbers. But if you change subatomic mass numbers, carbon can't bond as easily as it does, and life can't exist. I'm not saying "the world has to be my way" just because I like it that way - I'm saying "the world has to be my way" because otherwise there would be no life on earth. Finally, saying one law of physics might change doesn't mean that they're all up for grabs! And seriously, you're lecturing me on closed-mindedness?-AmesGyo! 12:05, 6 May 2007 (EDT)

Ames, I'm sorry, but it is close-minded to insist that life can only exist a certain way. You won't find a single credible scientist to make such a close-minded claim. Be more open-minded and admit the obvious: it's possible that life could have existed with different half-lives for C-14 and other differences as well.--Aschlafly 12:43, 6 May 2007 (EDT)

Andy, I'm telling you it's not. Part of the miracle of life in the universe is that it can only exist in a slim number of circumstances. Changing C-14 would change the whole thing. To analogize, it would not be "closed minded" to say that, if the charge of the electron were slightly larger or slightly less, life would cease to exist - it's just true (Hawking, Brief History of time). Do you have a cite supporting the idea that changing C-14 would not prohibit life from forming? I ask because mainstream science disagrees with you, and before making such an outrageous claim, I'm sure you must've done some research. If your whole argument depends on me being "closed-minded," and yet you refuse to look up the science on it, I think it's fairly clear who's won.-AmesGyo! 12:45, 6 May 2007 (EDT)

Please find a source that specifically speaks to a change of the half life of Carbon-14 within the past 6000 years. Your article discussing change in an unrelated matter of physics over billions of years just doesn't cut it. Then, discuss it here, and we'll include it after it's been fully discussed.-AmesGyo! 13:41, 6 May 2007 (EDT)

From radiocarbon dating

This is from an older entry entitled "radiocarbon dating". Please identify any information here that you feel might improve this entry. A redirect from radiocarbon dating is being inserted to send it to "carbon dating"

Radiocarbon dating is a method for estimating the age of organic material by measuring the ratio of carbon-14 to carbon-12 present.

The method is based on the fact that the carbon-12 isotope of carbon is more stable, and therefore more common, than the radioactive carbon-14 isotope. Most of the carbon in the earth is buried deep underground, where any carbon-14 decays, leaving behind carbon-12. Nitrogen-14 atoms in the stratosphere are often struck by neutrons, converting them to carbon-14 atoms. But carbon-14 in the atmosphere mixes with ordinary carbon-12 and finds it way into all living creatures. Therefore the concentration of carbon-14 is higher in living creatures and in the atmosphere than it is in dead or buried forms of carbon.

Thus, archaeologists use radiocarbon dating to measure the age of dead bodies, fossils, and burnt wood. If the concentration of carbon-14 is almost as high as in the atmosphere, then the specimen was recently alive. If it is much lower, then the specimen has been dead a long time. The mathematical formula that is used to figure the time since death depends on the the measured concentration of carbon-14 in the atmosphere, and also on the half-life of carbon-14 (the time it takes for half the carbon-14 in a given sample to decay). The half-live of carbon-14 is commonly given as 5730 ± 40 years; however a global standard half-life of 5568 ± 30 years is also often employed.

Obviously, this formula depends on the atmosphere remaining roughly constant in its composition over time. Insofar as the natural level and distribution of carbon-14 varies over time, due to to atmospheric disturbances, the formula will need to be adjusted. For example, in the last few decades, testing of nuclear weapons in the atmosphere has increased the concentration of carbon-14 in the Northern Hemisphere. To account for this, standard calibration curves are used to take account of known chronological fluctuations, and results can be obtained which are rarely more than 700 years out.

Other isotopes with longer half-lives can also be used to date objects. However, each method has its own drawbacks.

Young-Earth creationists point out that the atmospheric ratio of carbon-12 to carbon-14 would have been affected by the global flood, as the flood buried massive quantities of living things,<ref>Batten 2007, p. 71.</ref> thus invalidating dating results from that era as secular science does not allow for this. As such dating results presume that there was no flood, the resulting dates are not proof that there was no flood, as anti-creationists often charge.

The entire thing is important...-AmesGyo! 11:48, 6 May 2007 (EDT)

See also

Radiometric dating methods

Bibliography

  • Quarternary Dating Methods, by M. Walker (Wiley & Sons, 2005).
  • Isotopes: Principles and Applications, by G. Faure and T. Mensing (Wiley & Sons, 2005).

Notes


I'm sure you have a good reason for reverting.

Please don't troll, and tell me why you reverted. The changes only made your science less misleading and wrong. As stated above...

  1. You give no source for the "carbon dating can only prove which is older."
  2. The carbon content of the atmosphere can be discerned by ice cores.
  3. Changing the C-14 half-life would require changing all of atomic physics in a very bad way.
  4. Carbon dating obviously doesn't work on oil, et al, and that shouldn't be portrayed as a "flaw."

I'm sure you have good answers to these points, or you wouldn't have reverted without using the talk page first, right?-AmesGyo! 12:01, 6 May 2007 (EDT)

Reference #2

The article used for reference 2 says that Dirac's theory still hasn't been proven and that there isn't strong enough evidence that the laws have changed. Maybe this reference and claim should be removed until a better source (if one exists) can be found. Jrssr5 14:56, 8 May 2007 (EDT)

To be honest, I'm really skeptical. If Dirac were right, he'd be the winner of a second Nobel Prize. And people usually listen to Nobel Prize winners. Sterile 19:06, 8 May 2007 (EDT)


Carbon dating verified through other methods

How do you explain the fact that carbon dating methods were verified through many other methods of dating? When Libby developed the method he checked his results using verified historical records pertaining to the life of Zoser during the thrid dynasty. Carbon dating has also been proven effective through comparing results from other unrelated aging methods such as U/T dating, Optically Stimulated Luminescence (OSL), Thermoluminescence, Electron Spin Resonance, Dendrochronology, and Potassium-Argon dating. I have personally tested the age of a buried hearth pit using carbon dating and OSL, and the results were he same. Prof0705 16:15, 13 May 2007 (EDT)

Poor "reference"

Reference stated as support for the "older than 50,000 years, carbon-dating is bad" is [1]

If you review that posting, it's sourced from someone's comment - not really good science. I think someone needs to volunteer to research the original Faure text on geochemistry

Inability to date carbonate rocks -- false?

"Additional anomalous results from carbon dating, which reinforce its limitations, include the inability to date carbonate rocks, which by confound the science behind the dating technique."

I don't want to remove the statement, in case someone has another reference, but in This report (watch out -- it's HUGE) clearly shows a carbon-dating experiment performed on carbonate materials. "We determined the carbon isotope ratio of carbonates on ground powders... by reacting them with concentrated H3PO4... and collecting the evolved CO2.... The evolved and frozen CO2 [was]... transferred to an Isogas precision isotope ratio mass spectrometer (PRISM) for isotopic determination. Error bars of measurements are 0.1‰" (page 336). Am I missing somehthing, or can I remove the statement? HelpJazz 21:07, 5 January 2008 (EST)

Ok nobody is responding still, so I'll give 24 hours then remove the statement. HelpJazz 11:43, 26 January 2008 (EST)
I'll look into this. Give me a day or so. Thanks.--Aschlafly 13:49, 26 January 2008 (EST)
Alright. I'm sure there's something I'm missing, but I can't figure out what. HelpJazz 16:01, 26 January 2008 (EST)
Have you had time to take a look at it yet? HelpJazz 16:48, 28 January 2008 (EST)

Removal of Information

Why is information being removed from the content page here?--Aschlafly 11:04, 21 January 2008 (EST)

The part about carbonate rocks I addressed two weeks ago (see the talk section directly above this one) and I thought I had waited sufficient time.
The other part I removed because the exact same information is presented in the section below, so I didn't think we needed to say the exact same thing twice. HelpJazz 16:10, 21 January 2008 (EST)
We certainly don't need to say anything twice, but didn't you remove this essential paragraph:
The rate of decay of 14C is such that 50% of the 14C in the sample will decay in 5730 years ... For this reason, scientists do not generally attempt to carbon date material that is believed to be older than about 50,000-60,000 years old.--Aschlafly 16:35, 21 January 2008 (EST)
P.S. I waited also before reverting, by posting the first message above in this new section.--Aschlafly 16:37, 21 January 2008 (EST)
I did, because I thought that what was written later said the same thing:
"Since the half-life of 14C is only 5715 years, after 50,000 years only about 1/500th of the 14C remains - and since even initially it is only present as a minute proportion of the whole (0.0000000001% of all Carbon atoms), measuring the exact quantity present with precision enough to be of use for dating purposes is extremely difficult. For this reason, scientists do not generally attempt to carbon date material that is believed to be older than about 50,000-60,000 years old. However, isotopes with longer half-lives may be used."
Many of the phrases are the same and it looks like they were written using the same source.
After I edited this morning I had class till 4, so I wasn't able to respond to the talk page in time. HelpJazz 16:46, 21 January 2008 (EST)
OK, you're right, but the redundancy near the end is the one to remove, which I've done. Thanks.--Aschlafly 17:06, 21 January 2008 (EST)
Thanks. I thought it was better to remove the first paragraph, but it doesn't really matter eaither way.
What about the statement "Additional anomalous results from carbon dating, which reinforce its limitations, include the inability to date carbonate rocks, which confound the science behind the dating technique"? As I mentioned in the section above, scientists were able to date carbonate rocks. This origonally had a {{fact}} tag, and when I went to find a reference which shows that this statement is true, it turns out I couldn't, but I could find a reference which directly refutes it. HelpJazz 17:22, 21 January 2008 (EST)


Calibration, Variable Rate of Intake & Atmospheric variability

As I am sure the poster is aware of, this phenomenon is well-known and documented. However, I have seen this phenomenon used to cast aspersions on the effectiveness of radiocarbon dating. Please see the wealth of information on the topic of carbon intake and reservoir correction available online. I'm not sure what sites pass as credible here, so I will only offer the suggestion to search for "carbon reservoir correction" on your favorite engine. I don't want to violate the 90/10 rule, but I wanted to get some discussion on this before attempting to edit the page. Thanks, -- CWood 11:31, 2 January 2009 (EST)

What exactly in the article do you think needs changing? Philip J. Rayment 19:04, 2 January 2009 (EST)

I don't understand the point of mentioning these phenomena without also explaining the methods of accounting for them. So to answer your question, I believe an addition needs to be made explaining how and why intake rates vary and how and how and why they are corrected/calibrated. I understand that the point of the article is in fact to cast aspersion on radiocarbon dating, but I would not endorse doing so in a manner that is so easily controvertible by a quick google search. CWood 11:54, 13 January 2009 (EST)

The article already touches on your points, and doesn't really say a lot about the phenomena otherwise, but I guess that the article could do with some expansion in that regard.
The point of the article is to describe carbon dating, including its limitations. I believe that it does that reasonably well.
Philip J. Rayment 04:06, 14 January 2009 (EST)

I agree that the article describes carbon dating reasonably well and I understand that the target is a high school level audience. My point is that by not explaining how scientists attempt to cover the limitations of carbon dating Conservapedians highlighting these limitations may be caught off guard by the introduction of an unknown resource, for instance, reservoir correction tables. Conservapedian: "Carbon dating is limited by factors such as variable rate of intake." Liberal: "Not if you use reservoir correction." Conservapedian:"???" If you like, I will come up with something for your review.CWood 10:50, 15 January 2009 (EST)

Please do. Philip J. Rayment 16:58, 15 January 2009 (EST)

Don't censor info

Please add or clarify, but don't censor info here.--Andy Schlafly 23:06, 30 April 2009 (EDT)