Radiocarbon dating—the most common chronometric technique in archaeological and palaeoenvironmental research—creates challenges for established statistical methods. The methods assume that observations in a time-series are precisely dated, but this assumption is often violated when calibrated radiocarbon dates are used because they usually have highly irregular uncertainties.
Our simulation experiments yielded three main findings regarding the impact of radiocarbon date uncertainty on the PEWMA method when it is used to identify correlations between a count-based archaeological time-series and a radiocarbon-dated palaeoenvironmental time-series:
The method’s true-positive rate ranges from 20–90%, with the most realistic rates being between 30 and 50%.
June 5, 2018 Cornell University
Radiocarbon dating is a key tool archaeologists use to determine the age of plants and objects made with organic material. But new research shows that commonly accepted radiocarbon dating standards can miss the mark -- calling into question historical timelines.
Archaeologist Sturt Manning and colleagues have revealed variations in the radiocarbon cycle at certain periods of time, affecting frequently cited standards used in archaeological and historical research relevant to the southern Levant region, which includes Israel, southern Jordan and Egypt. These variations, or offsets, of up to 20 years in the calibration of precise radiocarbon dating could be related to climatic conditions.
Radiocarbon helps date ancient objects—but it's not perfect
"There has been much debate for several decades among scholars arguing for different chronologies sometimes only decades to a century apart -- each with major historical implications. And yet these studies ... may all be inaccurate since they are using the wrong radiocarbon information," Manning said.
"Our work," he added, "should prompt a round of revisions and rethinking for the timeline of the archaeology and early history of the southern Levant through the early Biblical period."
Calibration presents another challenge. With the dawn of the Industrial Age, humans began emitting much more carbon dioxide, diluting the amount of radiocarbon in the atmosphere. Nuclear testing affects radiocarbon levels, too, and dramatically increased carbon-14 levels starting in the 1950s. Modern statistical methods and updated databases allow scientists to take humans’ effects on Earth’s atmosphere into account.
Radiocarbon dating isn’t a silver bullet: Context is everything, and it can be hard to determine if there’s a temporal relationship between two objects at an archaeological site.
Dr. John Baumgardner explains how the RATE team tested the different dating methods used to give the long ages, and they found carbon 14 where it shouldn’t be. They measured the helium diffusion rate in zircon, and set out to answer the following issue, how could most of 1.5 billion years’ worth of He (Helium) still be inside these zircons, when the direct laboratory measurements of the He migration rate show that most of that He ought to have escaped in just a few thousand years? Dr. Baumgardner gives a clear presentation on the dating methods and how the results corroborate the Biblical timescale.