In the past couple of days there has been a lot of blame-game, back-and-forth banter about the 1988 radiocarbon dating. I though I would republish a posting from almost three years ago. It follows:
Joe Marino, Sue Benford and the Carbon Dating of the Shroud of Turin
January 19, 2011
Joe Marino writes:
*Paul Damon, head of the U. of Arizona laboratory
*Jacque Evin, French C-14 expert present at the 1988 sample-taking
*Gabrial Vial, French textile expert present at the 1988 sample-taking
*Franco Testore, Italian French textile expert present at the 1988 sample-taking
*Harry Gove, inventor of the C-14 method, who had literally bet a companion that the Shroud was medieval and was heavily involved in various aspects of the dating, including working to keep STURP from being involved in any testing
Do you think the deck was stacked against us?
Yes! But Benford and Marino prevailed. Big time!
What Joe Marino and Sue Benford accomplished is monumental. They proposed that the material used for carbon dating was from an area of the shroud that had been mended using a process called invisible reweaving. Of course, as everyone involved in shroud research now knows, Ray Rogers, a Los Alamos chemist, doubted they were right. According to Nature’s Philip Ball, “Rogers thought that he would be able to ‘disprove [the] theory in five minutes.’” (brackets are Ball’s). Inside the Vatican, an independent journal on Vatican affairs, reported:
Ludicrous was a mild way of putting it. Rogers words were stronger. He thought of the two researchers as part of a lunatic fringe. In the end, however, Rogers proved himself wrong. And he was honest and bold enough to admit it. In a letter to the editor of the Skeptical Inquirer magazine he wrote:
I accepted the radiocarbon results, and I believed that the "invisible reweave" claim was highly improbable. I used my samples to test it. One of the greatest embarrassments a scientist can face is to have to agree with the lunatic fringe.
It would have been nice to see something similar from Timothy Jull in the recent paper he coauthored with Rachel Freer-Waters. Granted, he did not think that he found corroborating evidence in support of Marino and Benford. By simply accepting the presence of cotton fibers by saying that Gilbert Raes had found cotton, too, he sent a clear, unintended signal to everyone who understood Marino, Benford and Rogers that he didn’t get it. To others, it was an unfortunate misrepresentation of the evidence because it suggests that Jull ignored recent literature on the subject. The cotton evidence is very meaningful.
The presence of cotton fibers is better described as a material intrusion than by the more common term contamination. It is important because the best evidence suggests that it is not present anywhere else than in the sampling area and the adjacent Raes area. And since there was evidence of reweaving including visible clues, madder dye, alum and cotton, then it is reasonable to conclude that there might be newer linen fiber used in reweaving. Cotton may have been used to enable dye to stick to the fiber. Dye was probably used to make newer thread appear yellowed like the older thread. It would have been nice if Jull had acknowledged this as a reasonable possibility.
What specific chemical analysis of the samples was done before carbon dating? Anyone who has read the 2008 article in Chemistry Today, authored by Benford and Marino, knows how important this should have been. Did the labs consider this or even know about existing evidence that suggested that the sampling area was chemically different from the rest of the shroud? Rogers was clear on this matter when he was asked if they were aware of this or simply ignored it.
[I]t doesn’t matter if they ignored it or were unaware of it. Part of science is to assemble all the pertinent data. They didn’t even try.
Jull missed an extraordinary opportunity to address this possibility.
Material intrusion is a big problem in carbon dating. Students of radiocarbon dating technology are familiar with classic examples. For instance, it is almost impossible to date a sample from a peat bog when it is a mixture of decayed newer plants that grew (materially intruded) into older decayed plant matter. And there is the known problem of dating snails living in an artesian spring in Nevada. They were found to be “27,000 years old” at the moment of death because their shells were formed from existing ancient bicarbonate (materially intruded) that was depleted of much of its carbon 14.
Not only had Benford and Marino provided a theory, if not proof, that the carbon dating of the shroud was invalid because of material intrusion, they provided a new, surely more famous, example of material intrusion for radiocarbon dating education. Call it an instant classic example. But the lesson is bigger than that. Students and practicing scientists of radiocarbon technology need to wonder how so many scientists didn’t anticipate the problem given that there were ample warning signs at the time. Jull missed an opportunity to address the need for learning from many, many mistakes.
Jull probably had no difficulties publishing his paper in Radiocarbon. The deck was certainly not stacked against him. He is the lab director, now. The Arizona Board of Regents on behalf of the University of Arizona holds the copyright. Jull in fact is the editor, which makes the paper he coauthored seem less a carefully reviewed scientific paper (was it at all?) and more of an op-ed. This is particularly so since Jull was involved with Arizona’s role in the carbon dating since the beginning.