ChemEurope just this morning posted an interesting article, Fossil fuel emissions will complicate radiocarbon dating, warns scientist:
Fossil fuel emissions could soon make it impossible for radiocarbon dating to distinguish new materials from artefacts that are hundreds of years old. Carbon released by burning fossil fuels is diluting radioactive carbon-14 and artificially raising the radiocarbon ‘age’ of the atmosphere, according to a paper published in the PNAS.
Radiocarbon measurements have a range of uses, from analysing archaeological finds, to detecting fraudulent works of art, to identifying illegal ivory trading, to assessing the regeneration of brain cells in neurological patients. The new study suggests that some of these current uses will be affected over this century, depending on how much fossil fuel emissions increase or decrease.
The online Daily Times Gazette picked up the story and added this:
One of famous radiocarbon dating investigation is the Shroud of Turin, which allegedly has the image of Jesus Christ.
However, Scientists found that it was originated from 13th century, 1,200 years after the Death of Christ.
Of course.
Okay, but what does this has to do with the Shroud of Turin 1988 Radiocarbon 14 testing ?
Nothing. It is just interesting.
Thank you Dan. I appreciate that.
Interesting! Now the question is that we know that the shroud was in a fire do we know if any burning wood was around that fire? If so would this cause a problem with the C-14 dating?
Fluctuations in atmospheric C14 are nothing new, and, as Willy Wolfli observed nearly 40 years ago, have the effect of making 20th century artefacts indistinguishable in radiocarbon terms from 17th century ones. Even in the 14th century, there was a significant blip in atmospheric C14 such that an object with a radiocarbon reduction amounting to 600 years could actually date to almost any time in the 14th century.
But, no, John, being in a wood fire has no effect on the radiocarbon date of something. Firstly, any CO2 produced by the fire would not be taken up by the artefact (although experiments to try to see if it might have been carried out), but secondly, the wood itself would still have almost all its radiocarbon still intact. The ChemEurope article refers to the burning of fossil fuels, which, having been buried for millions of years, have no residual C14 left.
Paradoxically, so far the decrease in C14 due to fossil fuel burning has just about matched the increase due to nuclear weapons testing, although it seems it will overcome it shortly. Paradoxically also, the bigger the discrepancy the better from a dating point of view; if they carbon dated the same, to distinguish a 2015 shirt from a 1975 shirt could be quite difficult, but to distinguish a 2015 shirt from a 1075 shirt should be considerably easier.
Thanks Hugh for clearing that up for me.
The Daily Times Gazette should go back to sleep.