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Posts Tagged ‘radiocarbon’

Chart of Conference. Well, So Far, Anyways

October 11, 2014 18 comments

An Abstract for Today

October 4, 2014 21 comments

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The chronology of long Upper Pleistocene loess sequences in Eurasia is based on combined pedostratigraphy and radiocarbon dating of high-quality charcoal. The accuracy of such a chronology depends on the reproducibility and precision of the 14C dates. However, certain dates may show discrepancies with regard to their chronostratigraphic context based on series of coherent dates. In order to evaluate the consistency and variation in the 14C dates obtained from small charcoal pieces, this question was tested on a set of spruce wood remains with well-preserved tree rings found in the Middle Pleniglacial loess-loam sequence of Kurtak (central Siberia). Tree-ring analysis of five fairly large wood pieces from three successive layers, dated to about 30.0, 30.8, and 32.2–32.5 ka BP previously, was done by continuous sampling of 90–150 rings on each wood piece. This enabled direct comparison of the succession of tree rings with the 14C dates. A total of 133 dates was obtained for the five wood pieces. The results show fluctuations in the 14C dates within a time range between 1000 and 2000 yr. Four possible causes for such variation will be discussed herein: (1) internal variability of the AMS dating method; (2) outliers; (3) variations in the 14C background; and (4) external factors such as past atmospheric 14C variations.

The paper is Variability in Radiocarbon Dates in Middle Pleniglacial Wood from Kurtak (Central Siberia) by P Haesaerts, F Damblon, N Drozdov, V Checha, J van der Plicht appearing in Radiocarbon, Vol 56, No 3 (2014).

Tell me again about how reliable carbon dating always is.

Hat tip to Joe Marino

Categories: Carbon 14 Dating Tags:

Photo Rich, Wonderful Presentation by Emanuela Marinelli

August 4, 2014 22 comments

imageYou must see, read and appreciate Emanuela Marinelli’s Valencia 2012 PowerPoint presentation, The setting for the radiocarbon dating of the Shroud, now easily found on the Valencia page at shroud.com. Writes, Joe Marino:

Another item Barrie added to the Valencia page that I think warrants a separate posting (instead of me just commenting on the previous post) is Emanuela’s Power Point slides to her excellent C-14 paper. . . .

Let’s be clear:

New Photographs of the Samples from Oxford

July 10, 2014 2 comments

imagePam has sent some new pictures.  You may recall that she applied to Oxford University (under the UK Freedom of Information Act 2007) to supply the photographs and data surrounding the 1988 tests. This exchange took place:

“Professor Ramsey has put most of it online. (one of the samples is missing but the Shroud data is there).

I wrote to her and asked her to explain what she meant when she said a sample was missing. Her next email to me stated:

“If you look at the whole sample of three of the tested cloths p2574_5; p2576_5 and p2575_8 you can see the first three samples. But the last one (I suspect it is Louis’ cloak) is missing.

“I’m fairly sure the Shroud is p2575 – the only herringbone weave and it looks like other related images we’ve seen of nearby samples. But on Monday I will go back to the compliance officer and question it.”

She has followed up. Yesterday she wrote to me:

Just to say that Professor Ramsey has posted some fascinating photos of the sample online. 

They are not the official University photos but they add substantially to Shroud knowledge. In particular the Shroud of Turin sample shows the underside/ reverse of the cloth.  Has that ever been photographed before?  I don’t remember seeing it.

The official set from early June

The latest showing the underside as a PDF file (or click on the image above)

Of Extreme and not so Extreme Anti-Authenticists

June 24, 2014 Comments off

imageHow many times can you use allegedly in a single paragraph? Stephen Jones continues with his theory in this latest installment of allegation that Arizona’s Timothy Linick was the alleged hacker who rigged the computerized consoles of all three AMS systems.

As part of my evidence that Arizona radiocarbon laboratory physicist Timothy W. Linick(1946-4 June 1989)[7] was allegedly the primary hacker, who: 1) allegedly wrote and installed on Arizona radiocarbon dating laboratory’s AMS control console computer a program which ensured that the Shroud of Turin samples’ actual radiocarbon dates would be replaced by dates which, when calibrated, clustered around 1325; and 2) allegedly passed that program on to the KGB, for which he was allegedly working, to be installed by confessed KGB hacker Karl Koch (1965–3 June 1989)[8] on the AMS control console computers at Zurich and Oxford’s radiocarbon dating laboratories; here is my evidence that Linick allegedly leaked Arizona’s 1350 radiocarbon date of the Shroud to the Rev. H. David Sox, an American Episcopalian (sic) priest, teaching at the American school in London[10]. And that Sox in turn leaked that date to the media through Luckett and others, well before the official announcement on 13 October 1988.

Not that it matters all that much, that I can see.

Anyway, Hugh Farey recently and significantly commented about Stephen’s previous posting:

Stop Press: A little while ago Stephen either read this blog, or someone told him of the post above, and he inserted a comment into his latest posting to the effect that he realised his dates and chart with its non-overlapping bands were based on BP dates and needed calibrating. This he has now done, and amended his blog to show a new set of dates and a new chart which, curiously, still shows that the Oxford dates do not overlap either of the others. By using the tiny calibration diagram published in the Nature paper rather than an established calibration program, he has enabled himself to reinforce his convictions. This cannot be allowed to go uncriticised.

It is not clear that Stephen really understands the calibrating process, particularly when it comes to how to deal with quoted errors. Actually anybody can do it by using OxCal, which is online, easy to access, easy to use, and free. Stephen tried to do it using the tiny published calibration chart in the Nature paper, deriving his dates simply by adding and subtracting the error from the mean as published in the Nature paper, and attempting to read off the calendar date.

His results, and those from OxCal (to 95.4% probability) are as follows:

Arizona BP dates: 646 ± 31
Stephen’s calibration: 1290 – 1317
OxCal’s calibration: 1281 – 1396

Oxford BP dates: 750 ± 30
Stephen’s calibration: 1214 – 1266
OxCal’s calibration: 1222 – 1287

Zurich BP dates: 676 ± 24
Stephen’s calibration: 1286 – 1293
OxCal’s calibration: 1275 – 1388

Well, it’s only a few years here and there, what does it matter? But Stephen is a great pains to point out that by his calculation the Oxford dates still do not overlap either of the other two – which of course is untrue, and that the Arizona and Zurich dates only overlap by 25 years, which is also untrue. His finding of a minimum Oxford date of 1214 is grotesquely inaccurate and must surely be a typo, but his even more inaccurate maximum misreading has a serious effect on his later argument – I wonder if it could be deliberate fraud?

Stephen blazes on.  It doesn’t matter. A target date will do nicely. It seems, if I’ve understood Stephen correctly, Linick was not a mere anti-authenticist, he was an extreme anti-authenticist unlike Gove and Hall who were non-extreme anti-authenticists. In other words, Linick was like McCrone who had written (extremely, I guess),  "A date significantly later than the first century would be conclusive evidence the `Shroud’ is not genuine. A date placing the linen cloth in the first century, though not conclusive in proving the cloth to be the Shroud of Christ…":

Linick, you see, said something similar. He said: “If we show the material to be medieval that would definitely mean that it is not authentic. If we date it back 2000 years, of course, that still leaves room for argument. It would be the right age – but is it the real thing?’"

This is evidence, Stephen says. Linick agreed with what McCrone stated eight years earlier. So, because McCrone had theorized that the cloth was painted about 1355, Linick can use that as a target date. Almost. To be more plausible, the date had to be “well before” 1355 to account for harvesting of the flax. 1350 will do nicely.

After this there is a lot of who knew who or talked to who. I’m reminded of the Monte Carlo simulations in the 1960s and 70s trying to prove that every individual in the world was connected to another by no more than six degrees of separation. At one point, Stephen tells us that he has been told privately of a possible connection between three anti-something-or-others, Sox, Luckett and Rose. But he is not free to tell us that. He just did, of course. He just won’t tell you who told him.

In the end he tells us it is an irresistible inference, Linick leaked the 1350 date to Sox. Okay. And the point is?

Stay tuned. There is another installment coming next week.

Anticipating the Conference: Neutrons Released from Resurrecting Jesus?

June 15, 2014 1 comment

Robert Rucker  |  11-Oct-2014  |  11:30 -12:30 am

imageMCNP ANALYSIS OF NEUTRONS RELEASED FROM JESUS’ BODY IN THE RESURRECTION

A computer code called MCNP is used in the nuclear industry for analysis and design of nuclear reactors, radiation detectors, radiation shielding, and criticality safety.  In this study, MCNP was used for a detailed analysis of neutron absorption in the shroud.  This study is based on the hypothesis that a very small fraction of neutrons in the body of Jesus were emitted from the body as it disappeared in the resurrection.

[ . . . ]

4.  The Sudarium of Oviedo has been carbon dated to about 750 A.D.  MCNP results indicate that a piece of cloth placed anywhere on 28% of the area of the right or left bench in the tomb would have a C14 date between 700 and 800 A.D.  This would explain the C14 date for the Sudarium.

Click on the title to read the full abstract. Click here for the conference home page.

Conspiracy Theory Part 4

June 8, 2014 30 comments

imageStephen Jones has posted another article attempting to advance his conspiracy theory that the carbon dating results were manipulated at all three labs by computer hackers. Over and over he has charged one of the Arizona physicist with being part of a KGB led conspiracy to fake the results and make the shroud appear medieval.

Today is as close as he has gotten to providing evidence: He tells us that a skeptic, Dennis Dutton, in 1986 “predicted that if the cloth ever were to be dated using radiocarbon dating it would be shown to have been from about 1335, give or take 30 years.”  Moreover, Walter McCrone in 1981 suggested that the cloth wasd from about 1355.

And so Stephen writes in a very long rambling posting:

So a hacker would know what date to `give’ the Shroud for maximum effect: shortly before 1335-1355! And, as we shall see, there is evidence that Linick was at least familiar with McCrone’s prediction.

Linick was at least familiar with McCrone’s prediction. No, there is no more yet. Anyway, you might want to read it.

To be continued in part 5, he tells us. I can hardly wait.

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