"I don't know" is not an explanation.
Don't misrepresent, please. They didn't say "I don't know" what's producing the readings, they said that contamination was producing it. For example:
Rather than deal with the issue of the nature of the 14 C intrinsic to the anthracite itself, the authors merely refer to it as “contamination of the sample in situ”, “not [to be] discussed further.”And:
This same approach of treating measurable and reproducible 14 C values in samples that ought to be 14 C dead, given their position in the geological record, as ‘contamination’ is found throughout the current literature.The fact that you apparently don't agree with their explanation or you consider it inadequate doesn't change the fact that they do, indeed, have one. And it appears to be the correct one -- see my next post.
The primary researcher's tried and tried to eliminate the anomalous result. They failed. The result was. "I don't know".
No, they did numerous things which would likely eliminate *surface* contamination (from the original site as well as during transport/testing) and contamination of the testing equipment, and concluded that the readings were thus coming from contamination *in* the sample itself. That's not "failure", that's successful elimination of other factors. The result was not "I don't know", it was "we now think that the contamination is likely from within the sample and not from *external* contamination".
Any of your hypothetical explanations fails to account for the tests used by the primary researchers and described by the "non-reading" current authors.
Oh? How do you figure that? You forgot to "show your work".
Now you might note that Giem is cited from [18] Giem, P., Carbon-14 Content of Fossil Carbon, Origins, 51(2001) pp.6-30. and these are the primary researchers on the case I mentioned [30] Nadeau, M.-J., Grootes, P.M., Voelker, A., Bruhn, F., Duhr, A., and Oriwall, A., Carbonate 14C Background: Does It Have Multiple Personalities?, Radiocarbon, 43:2A(2001), pp. 169-176.. Giem does not cite them.
Yes, I "might" note that, since I was the one to point that out to you in my prior post:
That refers *only* to citation #30, and describes their inability to explain why C14 levels would be correlated with species. It's not a summation of all the "primary researchers" [i.e., the dozen-plus cited by Giem].Is there any special reason you're repeating it back to me?
Finally, despite your aspersions, Uranium is not as ubiquitous as Nitrogen.
Red herring alert. Not only did I not claim that it was, but that's irrelevant to the point I made. I would be highly interested to hear why you thought it was.
What is relevant, however, is that Uranium is more ubiquitous than Carbon-14. The human body, for example, contains about a thousand times as many Uranium atoms as Carbon-14 atoms, and in long-dead organisms the disparity is even greater. Carbon-14 is present in only trace amounts even at the best of times (it comprises only 0.0000000002% of the Carbon in living tissue). It doesn't take much C-14 from other sources (internal or external) to contaminate things.
Furthermore, Carbon-14 can be produced in situ by muon capture by Oxygen nuclei -- and needless to say organic material has a lot of Oxygen. See for example In situ produced 14 C by cosmic ray muons in ablating Antarctic ice. Additional measurable C-14 was produced at depths of over 40 meters.
The authors of the PDF failed to examine either of these possible sources of de novo Carbon-14, among others, as well as the possibility that there may be others sources which we just haven't learned about yet (note that Ac-225's alternate decay mode into Carbon-14 was only discovered in 1993, for example).
However, it seems that the real explanation is simple surface contamination after all. See my next post.