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I do not understand why the information regarding the fact that there are groups that dispute the accuracy of carbon dating continues to be removed from this article. Please can those involved explain their actions? Many thanks, -- Rebroad 00:07, 5 February 2007 (UTC)
Removed:
In the Bible, the Hebrew word used for "day" is "yohm", which often means different lengths of time, such as the length of time it takes for a season, which takes a few months - much longer than a 24 hour day. It can be used to describe the period of time it takes for an event to occur, and thus if these "days" took millions or billions of years it would still be accurate to the meaning.
Responses to RfC
A sample covered by Noah's flood for a year or so would totally contaminate the sample. Considering everything was under water 4400 years ago, any sample that is analyzed has been contaminated. The dates assume that the samples are not contaminated and that the decay has been constant for the life of the sample, which cannot be proven. -- Ryanincabo ( talk) 15:33, 27 April 2010 (UTC)(UTC)
In order to address the "controversy" could someone include a discussion around why we are confident that the ratio of Carbon 12 to Carbon 14 in the atmosphere has remained a constant. I understand the issue is that the current ratio (100 Trillion to 1) when extrapolated back has remained fairly constant according to the "old age" camp and was much different according to the "young age" camp. If the focus was on the reasons for the accepted extrapolated ratio surely the "controversy" could be managed without turning the article into a discussion of religion etc — Preceding unsigned comment added by 86.26.184.88 ( talk) 21:03, 15 June 2011 (UTC)
In a section titled "Calibration" the last paragraph is:
As a consequence, the radiocarbon method shows limitations on dating of materials that are younger than the industrial era. Due to these fluctuations, greater carbon-14 content cannot be taken to mean a lesser age. It is expected that in the future the radiocarbon method will become less effective. A calibration curve must sometimes be combined with contextual analysis, because there is not always a direct relationship between age and carbon-14 content.[13]
I am not sure if ref 13 is supposed to support the whole paragraph or just the last sentence, but it does neither. The reference ("Coral corrects carbon dating problems.") is a 1990 Science News article describing how using ancient coral reefs, radiocarbon dating accuracy is improved. The article has no mention of industrial era or predictions for decreased assay accuracy in the future. The article concludes that, as common sense would dictate, a refined calibration curve for a particular assay improves the assay accuracy. Desoto10 ( talk) 04:45, 25 February 2011 (UTC)
I have a problem with this calculation. It seems like this method of dating postulate two truths.
These two claims are the result of an extrapolation, that although they might be used as a gauging measure, they might also, sometimes be ,way off the true age of the sample.-- Namaste@ ? 02:44, 8 July 2011 (UTC)
The Wiki article says, "He [Libby] first demonstrated the accuracy of radiocarbon dating by accurately estimating the age of wood from an ancient Egyptian royal barge for which the age was known from historical documents."
But according to source cited (source #2), it states the following:
"The next sample was furnished by John Wilson, of the Oriental Institute at the University of Chicago, and was a piece of wood from a mummiform coffin from Egypt, dated on stylistic grounds in the Ptolemaic period 332–30 B.C."
My contention?
The Wiki author's statement is misleading; it makes one think that there was some kind of manuscript evidence stating the date of an ancient Egyptian royal barge, when the source makes it abundantly clear that this barge's age was known through the use of stylistic dating. — Preceding unsigned comment added by 74.34.85.10 ( talk) 18:27, 18 August 2011 (UTC)
Anon has a point. I guess "royal barge" is from the museum site which is linked but now defunct. The linked paper of Libby et al was not his first on the subject, there is an earlier one (ref 10 in the linked paper, which is missing from that copy of it). The earlier paper refers to wood from two Egyptian tombs but there is no mention of barges and it doesn't say how the true ages were determined. I'll change the text shortly on the basis of Libby's two papers. Very likely there is more information about it in some reliably sources somewhere... Zero talk 00:53, 10 October 2011 (UTC)
I don't understand why this article uses British English. Radiocarbon dating was invented in the United States, and the -ize construction is used more than the British -ise in the article. I think we should change it. -- Serpinium ( talk) 15:46, 31 August 2015 (UTC)
It's not clear thru this article whether "cal" refers to "calendar" or "calibrated". The difference can be significant. Kortoso ( talk) 20:41, 7 July 2016 (UTC)
KLindblom, I have a couple of suggestions and questions about your changes to the history section.
Let me know what you think. -- Mike Christie ( talk - contribs - library) 03:11, 10 October 2016 (UTC)
A note in British Archaeology, the magazine of the Council for British Archaeology, states
Congratulations to Mike for his work in producing such an authoritative article. Dudley Miles ( talk) 19:49, 30 October 2016 (UTC)
I don't deny that Carbon-dating could be useful, but I feel that scientists might have made a mistake. Where did they get that half-life number, for instance, and are they sure that the radio-activeness rotted evenly? With (I hope) all due respect, I feel they should rethink their theory or mention the fact that they used carbon-dating whenever they did. With both respect and frustration, Myrrhfrankincensegold ( talk) —Preceding undated comment added 23:23, 21 December 2016 (UTC)
"The radiocarbon dating method is based on the fact that radiocarbon is constantly being created in the atmosphere by the interaction of cosmic rays with atmospheric nitrogen."
This could definitely use a reference or a sentence of explanation as it seems that this is saying that cosmic rays transmute nitrogen into carbon, which is rather amazing. — Preceding unsigned comment added by 75.173.77.201 ( talk • contribs)
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This section contained the phrase "... it was this paper that gave Libby the idea..." but the previous text in the wiki article didn't mention a particular publication. I've dug a little further to identify which paper was meant and found there were several papers by Korff but none quite stated that the interaction of slow neutrons with N14 in the atmosphere "was the main pathway". I've tweaked the text. Also Korff wasn't at NY Uni at the time.
Google preview allows me to see Taylor & Bar-Yosef 2014 on page 269 - and also Note 38 on page 325
- Aa77zz ( talk) 15:16, 6 January 2017 (UTC)
The page currently states, 'The 13C/12C ratio is used instead of 14C/12C because the former is much easier to measure, and the latter can be easily derived.' I am not a subject expert, but question whether this is incorrect. Should it read, 'The 14C/12C ratio is used instead of 13C/12C because the former is much easier to measure, and the latter can be easily derived.'? — Preceding unsigned comment added by AHDGraham ( talk • contribs) 07:15, 7 October 2017 (UTC)
Why is this written in British English when "the method was developed in the late 1940s by Willard Libby," an American? This should obviously be written in American English. 95.49.133.63 ( talk) 15:54, 21 November 2018 (UTC)
https://gizmodo.com/two-stalagmites-found-in-chinese-cave-are-a-holy-grail-1831074289
The above is interesting and the info from it should probably go into the article. 173.228.123.166 ( talk) 12:18, 15 December 2018 (UTC)
I've just read the article, and was going to add something like this:
That's a bit bare-bones and context-free, though. What I'd really like to say is something like "this data will be incorporated into the next INTCAL curve" and will help improve the accuracy of 14C dating", but I can't do that with just this article. Any thoughts on how to integrate this? Mike Christie ( talk - contribs - library) 11:49, 16 December 2018 (UTC)
A version of this article has been published in the WikiJournal of Science. I am about to go through the article and change some of the text to incorporate modifications made to that article during peer review. If anyone feels the changes are not an improvement, please comment here. Mike Christie ( talk - contribs - library) 20:16, 9 June 2018 (UTC)
Mike Christie. You may be interested in a new method of dating pottery by radiocarbon dating of milk fat residues reported in the latest edition of Current Archaeology. It is described as a "potentially revolutionary advancement" and the report is based on an article in Nature at [1]. Dudley Miles ( talk) 19:15, 12 May 2020 (UTC)
To editor Mike Christie: This article is stuck at IntCal13 and could use an update to the present. It's a bit peripheral to my expertise, so this is a friendly nudge in your direction. Zero talk 06:16, 9 September 2020 (UTC)
The term "apparent age" / "apparent date" is not introduced before its first use in the article. I kinda hope it will be clearly defined somewhere, but I am not an expert on the topic. Maybe this citation would help? "the 14
C relative to the time of death" (or when the primary activity ends).
Dating an object from the early 20th century hence gives an apparent date older than the true date, for example (the preceding sentence in the article explains why this is). Can you say what would make this clearer to a reader? Mike Christie ( talk - contribs - library) 12:30, 16 November 2020 (UTC)
Coal and oil began to be burned in large quantities during the 19th century. Both are sufficiently old that they contain little or no detectable 14C and, as a result, the CO2 released substantially diluted the atmospheric 14C/12 C ratio. Dating an object from the early 20th century hence gives an apparent date older than the true date.What this means is that if you didn't know about effect of the coal and oil, and ran a radiocarbon date on a bone from 1940, it would give you a date much older than 1940 because the carbon released by burning coal and oil had changed the 14C in the atmosphere by 1940. So someone who didn't take this into account would come up with a date of, say, 1890 (I don't know what the actual error would be). That's the apparent date; the date it appears to be if you don't take the fossil fuel effect into account. The usage later in the article is similar -- if you use radiocarbon dating without understanding e.g. the marine offset, you're going to get radiocarbon dates that are wrong -- they are apparently date X, but if you apply the right correction you get the correct answer, Y. Is that clearer? Mike Christie ( talk - contribs - library) 17:35, 16 November 2020 (UTC)
Oops, didn't mean to flatter or something. Thanks for the explanation! In the article, it says The calculations involve several steps and include an intermediate value called the "radiocarbon age"
... an age quoted in radiocarbon years means that no calibration curve has been used
. So using the same example in your explanation above, a carbon dating result is calculated like this:
173.75.41.7 ( talk) 20:04, 17 November 2020 (UTC)
So, is there a need to change the article? Or a way to improve it slightly? -- Hob Gadling ( talk) 07:12, 22 November 2020 (UTC)
Under "Calibration", the sentence "For example, 'cal 1220–1281 AD (1σ)' means a calibrated date for which the true date lies between 1220 AD and 1281 AD, with the confidence level given as 1σ, or one standard deviation." - looks very convincing, interpreting the two dates as expressing ±1σ. In contrast, calibrating the age of Ötzi (the iceman) with given 4550 ±19 (= 1σ) BP, OxCal yields for all three confidence levels (68.3; 95.4; 99.7) naturally the same mean μ, however and surprisingly, also the same sigma =89, in spite of naturally different overall dates. For me, the OxCal output is logically contradicting the cited sentence. Any idea? HJHolm ( talk) 14:28, 15 June 2021 (UTC)
As just tested, CALIB confuses the input, taking the "BP" input as ID, and the sigma as BP-age. 2A02:8108:9640:AC3:70A7:CB14:FF18:1B02 ( talk) 08:07, 3 July 2021 (UTC)
The term redirects here (at the Calibration section) but the article doesn't even define what a plateau is, not to mention any kind of discussion, and neither does Radiocarbon calibration nor Wiggle matching. It took me a search at the archives of the talk page to find one (by Peter.steier, who is sadly not active for years):
Changes in ocean circulation can release large amounts of "old" marine CO2 into the atmosphere. This old CO2 will be incorparated by living organisms, which will reveal an older radiocarbon age than they "should". They might even have a lower C-14 concentration while they still live than their ancestors a few decades or centuries ago (and have already lost some of their initial C-14 by decay). These are the "wiggles", actually reverting the true and the apparent age.
A "plateau" appears if, over a certain time interval, the change in the atmosphere (due to production changs, reservoir exchange, etc.) BY CHANCE matches the decay-driven change in already dead organisms. All samples from this time interval will finally reveal the same radiocarbon content. If all samples yield the same measurement result independent of their age, dating is impossible (i.e. the uncertainty is the length of the plateau, 800 years for the Hallstadt, independent of the precision of the C-14 measurement). Naturally, perfect plateaus never exist, but the Hallstadt and the Younger Dryas are relatively flat.
— User:Peter.steier
— /Archive 5#Hallstatt plateau 16:22, 13 February 2011 (UTC)
Could anyone please find some sources and incorporate that into the article body? Ain92 ( talk) 16:59, 8 August 2022 (UTC)
Footnote 12 now reads: because its gradual decay is cancelled out by a gradual temporary increase in the amount of 14C in the atmosphere.
– this is wrong - or at least very confusing. The plateau arises when the 14C/12C ratio of the atmosphere decreases at the same rate as the reduction in 14C/12C due to radioactive decay. To quote the cited article "For the duration of such a plateau, the 14C/12C ratio fell at a rate equal to that of radiocarbon decay." -
Aa77zz (
talk)
19:52, 11 August 2022 (UTC)
I've tweaked the footnote again. I didn't like when the level of 14
. New text: "A plateau in the calibration curve occurs when the ratio of 14
C in samples remains constant
C/12
C in the atmosphere decreases at the same rate as the reduction due to radiocarbon decay in the sample." -
Aa77zz (
talk)
08:19, 12 August 2022 (UTC)
![]() | This is an archive of past discussions. Do not edit the contents of this page. If you wish to start a new discussion or revive an old one, please do so on the current talk page. |
Archive 1 | ← | Archive 4 | Archive 5 | Archive 6 |
I do not understand why the information regarding the fact that there are groups that dispute the accuracy of carbon dating continues to be removed from this article. Please can those involved explain their actions? Many thanks, -- Rebroad 00:07, 5 February 2007 (UTC)
Removed:
In the Bible, the Hebrew word used for "day" is "yohm", which often means different lengths of time, such as the length of time it takes for a season, which takes a few months - much longer than a 24 hour day. It can be used to describe the period of time it takes for an event to occur, and thus if these "days" took millions or billions of years it would still be accurate to the meaning.
Responses to RfC
A sample covered by Noah's flood for a year or so would totally contaminate the sample. Considering everything was under water 4400 years ago, any sample that is analyzed has been contaminated. The dates assume that the samples are not contaminated and that the decay has been constant for the life of the sample, which cannot be proven. -- Ryanincabo ( talk) 15:33, 27 April 2010 (UTC)(UTC)
In order to address the "controversy" could someone include a discussion around why we are confident that the ratio of Carbon 12 to Carbon 14 in the atmosphere has remained a constant. I understand the issue is that the current ratio (100 Trillion to 1) when extrapolated back has remained fairly constant according to the "old age" camp and was much different according to the "young age" camp. If the focus was on the reasons for the accepted extrapolated ratio surely the "controversy" could be managed without turning the article into a discussion of religion etc — Preceding unsigned comment added by 86.26.184.88 ( talk) 21:03, 15 June 2011 (UTC)
In a section titled "Calibration" the last paragraph is:
As a consequence, the radiocarbon method shows limitations on dating of materials that are younger than the industrial era. Due to these fluctuations, greater carbon-14 content cannot be taken to mean a lesser age. It is expected that in the future the radiocarbon method will become less effective. A calibration curve must sometimes be combined with contextual analysis, because there is not always a direct relationship between age and carbon-14 content.[13]
I am not sure if ref 13 is supposed to support the whole paragraph or just the last sentence, but it does neither. The reference ("Coral corrects carbon dating problems.") is a 1990 Science News article describing how using ancient coral reefs, radiocarbon dating accuracy is improved. The article has no mention of industrial era or predictions for decreased assay accuracy in the future. The article concludes that, as common sense would dictate, a refined calibration curve for a particular assay improves the assay accuracy. Desoto10 ( talk) 04:45, 25 February 2011 (UTC)
I have a problem with this calculation. It seems like this method of dating postulate two truths.
These two claims are the result of an extrapolation, that although they might be used as a gauging measure, they might also, sometimes be ,way off the true age of the sample.-- Namaste@ ? 02:44, 8 July 2011 (UTC)
The Wiki article says, "He [Libby] first demonstrated the accuracy of radiocarbon dating by accurately estimating the age of wood from an ancient Egyptian royal barge for which the age was known from historical documents."
But according to source cited (source #2), it states the following:
"The next sample was furnished by John Wilson, of the Oriental Institute at the University of Chicago, and was a piece of wood from a mummiform coffin from Egypt, dated on stylistic grounds in the Ptolemaic period 332–30 B.C."
My contention?
The Wiki author's statement is misleading; it makes one think that there was some kind of manuscript evidence stating the date of an ancient Egyptian royal barge, when the source makes it abundantly clear that this barge's age was known through the use of stylistic dating. — Preceding unsigned comment added by 74.34.85.10 ( talk) 18:27, 18 August 2011 (UTC)
Anon has a point. I guess "royal barge" is from the museum site which is linked but now defunct. The linked paper of Libby et al was not his first on the subject, there is an earlier one (ref 10 in the linked paper, which is missing from that copy of it). The earlier paper refers to wood from two Egyptian tombs but there is no mention of barges and it doesn't say how the true ages were determined. I'll change the text shortly on the basis of Libby's two papers. Very likely there is more information about it in some reliably sources somewhere... Zero talk 00:53, 10 October 2011 (UTC)
I don't understand why this article uses British English. Radiocarbon dating was invented in the United States, and the -ize construction is used more than the British -ise in the article. I think we should change it. -- Serpinium ( talk) 15:46, 31 August 2015 (UTC)
It's not clear thru this article whether "cal" refers to "calendar" or "calibrated". The difference can be significant. Kortoso ( talk) 20:41, 7 July 2016 (UTC)
KLindblom, I have a couple of suggestions and questions about your changes to the history section.
Let me know what you think. -- Mike Christie ( talk - contribs - library) 03:11, 10 October 2016 (UTC)
A note in British Archaeology, the magazine of the Council for British Archaeology, states
Congratulations to Mike for his work in producing such an authoritative article. Dudley Miles ( talk) 19:49, 30 October 2016 (UTC)
I don't deny that Carbon-dating could be useful, but I feel that scientists might have made a mistake. Where did they get that half-life number, for instance, and are they sure that the radio-activeness rotted evenly? With (I hope) all due respect, I feel they should rethink their theory or mention the fact that they used carbon-dating whenever they did. With both respect and frustration, Myrrhfrankincensegold ( talk) —Preceding undated comment added 23:23, 21 December 2016 (UTC)
"The radiocarbon dating method is based on the fact that radiocarbon is constantly being created in the atmosphere by the interaction of cosmic rays with atmospheric nitrogen."
This could definitely use a reference or a sentence of explanation as it seems that this is saying that cosmic rays transmute nitrogen into carbon, which is rather amazing. — Preceding unsigned comment added by 75.173.77.201 ( talk • contribs)
Hello fellow Wikipedians,
I have just modified one external link on Radiocarbon dating. Please take a moment to review my edit. If you have any questions, or need the bot to ignore the links, or the page altogether, please visit this simple FaQ for additional information. I made the following changes:
When you have finished reviewing my changes, you may follow the instructions on the template below to fix any issues with the URLs.
An editor has reviewed this edit and fixed any errors that were found.
Cheers.— InternetArchiveBot ( Report bug) 14:59, 11 November 2017 (UTC)
This section contained the phrase "... it was this paper that gave Libby the idea..." but the previous text in the wiki article didn't mention a particular publication. I've dug a little further to identify which paper was meant and found there were several papers by Korff but none quite stated that the interaction of slow neutrons with N14 in the atmosphere "was the main pathway". I've tweaked the text. Also Korff wasn't at NY Uni at the time.
Google preview allows me to see Taylor & Bar-Yosef 2014 on page 269 - and also Note 38 on page 325
- Aa77zz ( talk) 15:16, 6 January 2017 (UTC)
The page currently states, 'The 13C/12C ratio is used instead of 14C/12C because the former is much easier to measure, and the latter can be easily derived.' I am not a subject expert, but question whether this is incorrect. Should it read, 'The 14C/12C ratio is used instead of 13C/12C because the former is much easier to measure, and the latter can be easily derived.'? — Preceding unsigned comment added by AHDGraham ( talk • contribs) 07:15, 7 October 2017 (UTC)
Why is this written in British English when "the method was developed in the late 1940s by Willard Libby," an American? This should obviously be written in American English. 95.49.133.63 ( talk) 15:54, 21 November 2018 (UTC)
https://gizmodo.com/two-stalagmites-found-in-chinese-cave-are-a-holy-grail-1831074289
The above is interesting and the info from it should probably go into the article. 173.228.123.166 ( talk) 12:18, 15 December 2018 (UTC)
I've just read the article, and was going to add something like this:
That's a bit bare-bones and context-free, though. What I'd really like to say is something like "this data will be incorporated into the next INTCAL curve" and will help improve the accuracy of 14C dating", but I can't do that with just this article. Any thoughts on how to integrate this? Mike Christie ( talk - contribs - library) 11:49, 16 December 2018 (UTC)
A version of this article has been published in the WikiJournal of Science. I am about to go through the article and change some of the text to incorporate modifications made to that article during peer review. If anyone feels the changes are not an improvement, please comment here. Mike Christie ( talk - contribs - library) 20:16, 9 June 2018 (UTC)
Mike Christie. You may be interested in a new method of dating pottery by radiocarbon dating of milk fat residues reported in the latest edition of Current Archaeology. It is described as a "potentially revolutionary advancement" and the report is based on an article in Nature at [1]. Dudley Miles ( talk) 19:15, 12 May 2020 (UTC)
To editor Mike Christie: This article is stuck at IntCal13 and could use an update to the present. It's a bit peripheral to my expertise, so this is a friendly nudge in your direction. Zero talk 06:16, 9 September 2020 (UTC)
The term "apparent age" / "apparent date" is not introduced before its first use in the article. I kinda hope it will be clearly defined somewhere, but I am not an expert on the topic. Maybe this citation would help? "the 14
C relative to the time of death" (or when the primary activity ends).
Dating an object from the early 20th century hence gives an apparent date older than the true date, for example (the preceding sentence in the article explains why this is). Can you say what would make this clearer to a reader? Mike Christie ( talk - contribs - library) 12:30, 16 November 2020 (UTC)
Coal and oil began to be burned in large quantities during the 19th century. Both are sufficiently old that they contain little or no detectable 14C and, as a result, the CO2 released substantially diluted the atmospheric 14C/12 C ratio. Dating an object from the early 20th century hence gives an apparent date older than the true date.What this means is that if you didn't know about effect of the coal and oil, and ran a radiocarbon date on a bone from 1940, it would give you a date much older than 1940 because the carbon released by burning coal and oil had changed the 14C in the atmosphere by 1940. So someone who didn't take this into account would come up with a date of, say, 1890 (I don't know what the actual error would be). That's the apparent date; the date it appears to be if you don't take the fossil fuel effect into account. The usage later in the article is similar -- if you use radiocarbon dating without understanding e.g. the marine offset, you're going to get radiocarbon dates that are wrong -- they are apparently date X, but if you apply the right correction you get the correct answer, Y. Is that clearer? Mike Christie ( talk - contribs - library) 17:35, 16 November 2020 (UTC)
Oops, didn't mean to flatter or something. Thanks for the explanation! In the article, it says The calculations involve several steps and include an intermediate value called the "radiocarbon age"
... an age quoted in radiocarbon years means that no calibration curve has been used
. So using the same example in your explanation above, a carbon dating result is calculated like this:
173.75.41.7 ( talk) 20:04, 17 November 2020 (UTC)
So, is there a need to change the article? Or a way to improve it slightly? -- Hob Gadling ( talk) 07:12, 22 November 2020 (UTC)
Under "Calibration", the sentence "For example, 'cal 1220–1281 AD (1σ)' means a calibrated date for which the true date lies between 1220 AD and 1281 AD, with the confidence level given as 1σ, or one standard deviation." - looks very convincing, interpreting the two dates as expressing ±1σ. In contrast, calibrating the age of Ötzi (the iceman) with given 4550 ±19 (= 1σ) BP, OxCal yields for all three confidence levels (68.3; 95.4; 99.7) naturally the same mean μ, however and surprisingly, also the same sigma =89, in spite of naturally different overall dates. For me, the OxCal output is logically contradicting the cited sentence. Any idea? HJHolm ( talk) 14:28, 15 June 2021 (UTC)
As just tested, CALIB confuses the input, taking the "BP" input as ID, and the sigma as BP-age. 2A02:8108:9640:AC3:70A7:CB14:FF18:1B02 ( talk) 08:07, 3 July 2021 (UTC)
The term redirects here (at the Calibration section) but the article doesn't even define what a plateau is, not to mention any kind of discussion, and neither does Radiocarbon calibration nor Wiggle matching. It took me a search at the archives of the talk page to find one (by Peter.steier, who is sadly not active for years):
Changes in ocean circulation can release large amounts of "old" marine CO2 into the atmosphere. This old CO2 will be incorparated by living organisms, which will reveal an older radiocarbon age than they "should". They might even have a lower C-14 concentration while they still live than their ancestors a few decades or centuries ago (and have already lost some of their initial C-14 by decay). These are the "wiggles", actually reverting the true and the apparent age.
A "plateau" appears if, over a certain time interval, the change in the atmosphere (due to production changs, reservoir exchange, etc.) BY CHANCE matches the decay-driven change in already dead organisms. All samples from this time interval will finally reveal the same radiocarbon content. If all samples yield the same measurement result independent of their age, dating is impossible (i.e. the uncertainty is the length of the plateau, 800 years for the Hallstadt, independent of the precision of the C-14 measurement). Naturally, perfect plateaus never exist, but the Hallstadt and the Younger Dryas are relatively flat.
— User:Peter.steier
— /Archive 5#Hallstatt plateau 16:22, 13 February 2011 (UTC)
Could anyone please find some sources and incorporate that into the article body? Ain92 ( talk) 16:59, 8 August 2022 (UTC)
Footnote 12 now reads: because its gradual decay is cancelled out by a gradual temporary increase in the amount of 14C in the atmosphere.
– this is wrong - or at least very confusing. The plateau arises when the 14C/12C ratio of the atmosphere decreases at the same rate as the reduction in 14C/12C due to radioactive decay. To quote the cited article "For the duration of such a plateau, the 14C/12C ratio fell at a rate equal to that of radiocarbon decay." -
Aa77zz (
talk)
19:52, 11 August 2022 (UTC)
I've tweaked the footnote again. I didn't like when the level of 14
. New text: "A plateau in the calibration curve occurs when the ratio of 14
C in samples remains constant
C/12
C in the atmosphere decreases at the same rate as the reduction due to radiocarbon decay in the sample." -
Aa77zz (
talk)
08:19, 12 August 2022 (UTC)