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In a recent creationist video, he oh-so-subtly mentioned that there was the isotope carbon-14 (14C) not only in all layers of strata, but in equal amounts too, and that this was somehow proof of a world-wide flood. I have attempted to find a peer-reviewed scientific article regarding old rocks with carbon, but I've yet to find one.

I cannot, for the life of me, seem to find the video. I'll try my best, but I did find one article by the same guy: http://creationsciencehalloffame.org/2013/05/08/science/carbon-dating-believers-true-friend/

Reinstate Monica -- notmaynard
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Goodies
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1 Answers1

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There is virtually no 14C in rocks more than a few hundreds of thousands of years old as 14C is radioactive with a half-life of only about 5,730 years. There is negligible 14C in fossil fuels (such as coal) for a start, which directly contradicts any claim that the 14C is the same in all strata.

Addendum: While the article linked in the question states that 14C is found in fossil fuels and rock strata, it is notable that there is no evidence or citation provided allowing this to be verified. There are however papers that would support this claim, for instance this one

Baumgardner, John R., et al. "Measurable 14C in fossilized organic materials: confirming the young earth creation-flood model." Proceedings of the fifth international conference on creationism. Vol. 2. Creation Science Fellowship, Pittsburgh, PA, 2003. (pdf)

However, I wouldn't regard this as being a peer-reviewed scientific conference. If it were published in a regular scientific journal it would be rather different.

Note also that (as pointed out by @DavePhD in the comments below), small amounts of 14C may be formed in some rock strata by other mechanisms.

Reinstate Monica -- notmaynard
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  • This is precisely what I thought. I'm somewhat familiar with radioactivity and decay, but this man (Russ Miller, by the way) claimed that there was 14C found in all layers of strata in equal amounts. – Goodies Nov 03 '14 at 17:36
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    well if by "equal amounts" he means "essentially zero" he is technically correct ;o) –  Nov 03 '14 at 17:37
  • @DikranMarsupial In the atmosphere, carbon-14 is formed by neutron capture of cosmic ray neutrons. Why would zero carbon-14 form underground; are you saying there is zero neutron flux underground? See Background neutron flux determination at a depth of 3200 mwe underground http://www.sciencedirect.com/science/article/pii/0168900294015279 and see Development of low-background vacuum extraction and graphitization systems for 14C dating of old (40–60 ka) samples http://www.sciencedirect.com/science/article/pii/S1040618206003235 where millions of years old Ceylon graphite is found to have C-14 – DavePhD May 02 '16 at 13:56
  • While there may be neutron fluxes in the ground, there isn't a lot of Nitrogen (unlike the atmosphere) which AIUI is what captures the neutron (I'm not a nuclear physicist, so I don't know the mechanisms involved). The half life of 14C is about 5000 years, so 40ka is only 8 half lives, which would be 0.00004% of the amount that is in the atmosphere (if that was the source, as it would be in coal). That may be in the range detectable by science, but it is still an extremely small amount. –  May 02 '16 at 16:31
  • I couldn't see the reference to millions of years for the Ceylon graphite, but only " The upper limit of 14C dating for our systems depends on the mass of the graphite target. For a 1 mg target, the practical limit of our system is ∼55 ka; for a 0.5 mg target, the practical limit is ∼50 ka." Would it be better if I wrote "negligible" instead of "virtually no"? –  May 02 '16 at 16:31
  • @DavePhD note a decline of atmospheric 14C is one of the lines of evidence that tells us that the post-industrial rise in atmospheric CO2 is anthropogenic (http://archiv.ub.uni-heidelberg.de/volltextserver/6862/1/LevinRAD2000.pdf). The fossil carbon (being essentially free of 14C) "dilutes" the 14C in the atmosphere from natural sources with lighter isotopes. –  May 03 '16 at 09:30
  • @DikranMarsupial The Ceylon graphite references says "background levels of 0.04±0.02 pMC based on analyses of Ceylon graphite, equivalent to a 14C 'age' of 62.8±5.6 ka ". So it has an amount of C-14 that is significantly different than zero. Ceylon graphite is used as a blank because it is millions of years old (see 450-650 million here: https://books.google.com/books?id=VOfsAAAAMAAJ&q=vein+graphite+%22million+years%22+sri+lanka&dq=vein+graphite+%22million+years%22+sri+lanka&hl=en&sa=X&ved=0ahUKEwisxdC1673MAhXJeD4KHXofCTIQ6AEIPDAE). – DavePhD May 03 '16 at 12:00
  • @DikranMarsupial C-14 can also form from C-13 (which is 1.1% of carbon) by neutron capture. So underground material would have some low but non-zero C-14 content regardless of age, the amount being a function of N-14 and C-13 present in the material and neutron flux. C-14 can also form from decay of radium. https://en.wikipedia.org/wiki/Cluster_decay – DavePhD May 03 '16 at 12:13
  • @DavePhD I wrote "virtually no 14C" rather than "no 14C" (an exponential decay only goes to zero asymptotically anyway). As I pointed out, if Ceylon graphite has background levels equivalent to 60Ka, then that really isn't very much. According to Wikipedia, 14C is present at a level of 1 part per 10^12 in the atmosphere, after 40K years it will be 0.0039 times less. Now take a stratum that is not pure carbon, and so doesn't favour the 13C route and it will have even less 14C at time progresses. Is this really relevant to the original question? –  May 03 '16 at 13:45
  • Ah I see, I was less equivocal in the second sentence, I'll fix that, +1 –  May 03 '16 at 13:53
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    @DikranMarsupial I think it's relevant to the OP because the source in the OP is talking about finding C-14 in 570 million year old material "570 million years old, not only contain C-14, but in the same range of amounts from the top strata to the lowest layer". This is 100,000 half-lives! So on that time scale very small amounts of C-14 not originating from atmospheric CO2 but formed in situ would be the overwhelming majority of the C-14 present. Basically there would be a very low, but age-independent, C-14 content for materials that are millions of years old. – DavePhD May 03 '16 at 14:01
  • O.K. well why not just answer the question yourself, so I can upvote it. If you are going to point out that an answer is wrong, then it is probably best to point it out directly, rather than elliptically such as "are you saying there is zero neutron flux underground? ". When you have posted your answer, I'll delete mine as incorrect and upvote yours. –  May 03 '16 at 14:13
  • Incidentally, there are plenty of papers that say fossil carbon is devoid of 14C (e.g. http://www.pnas.org/content/112/31/9542.full.pdf) which shows the problem with this sites approach to "scientific skepticsm" ;o) –  May 03 '16 at 14:14
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    Now I asked a question about it on Earth Science SE http://earthscience.stackexchange.com/questions/7949/rate-of-underground-formation-of-carbon-14-by-neutron-capture – DavePhD May 03 '16 at 15:53
  • good idea, I'll leave my answer for the time being so your comments are available until you post an answer here. –  May 03 '16 at 15:55
  • "There is virtually no 14C in rocks more than a few hundreds of thousands of years old as 14C is radioactive with a half-life of only about 5,730 years." This is begging the question. The creationist is claiming that the isotope is evenly prevalent, proving that there are no rocks that old. – Oddthinking May 04 '16 at 16:28
  • Its funny how Creationists say that 14C dating is bogus because you can't be sure that half lives have remained constant over time, and then claim that their measurements of 14C prove their claims. – Paul Johnson May 04 '16 at 20:36