Climate records from a Japanese lake are set to improve the accuracy of the dating technique, which could help to shed light on archaeological mysteries such as why Neanderthals became extinct.
Carbon dating is used to work out the age of organic material — in effect, any living thing.
Marine records, such as corals, have been used to push farther back in time, but these are less robust because levels of carbon-14 in the atmosphere and the ocean are not identical and tend shift with changes in ocean circulation.
Bronk Ramsey’s team aimed to fill this gap by using sediment from bed of Lake Suigetsu, west of Tokyo.
As a rule, carbon dates are younger than calendar dates: a bone carbon-dated to 10,000 years is around 11,000 years old, and 20,000 carbon years roughly equates to 24,000 calendar years.
The problem, says Bronk Ramsey, is that tree rings provide a direct record that only goes as far back as about 14,000 years.
Carbon dating the Dead Sea Scrolls refers to a series of radiocarbon dating tests performed on the Dead Sea Scrolls, first by the AMS (Accelerator Mass Spectrometry) lab of the Zurich Institute of Technology in 1991 and then by the AMS Facility at the University of Arizona in Tucson in 1994-95.
There was also a historical test of a piece of linen performed in 1950 by Willard Libby, the inventor of the dating method.
She will lead efforts to combine the Lake Suigetsu measurements with marine and cave records to come up with a new standard for carbon dating.
The section of the calibration curve for the 14C age of the Habakkuk Commentary is complex, so that the 14C age of 2054 cuts through a few spikes on the curve, providing two date ranges.
The Great Isaiah Scroll 1QIsa has been tested three times, once by Libby, once at Zurich and once at Tucson.
The following table shows all the Qumran-related samples that were tested by Zurich (Z), Tucson (T) and Libby (L).
The column headed "14C Age" provides a raw age before 1950 for each sample tested.