Archaeology dating accuracy
The only other direct record of atmospheric carbon comes from tree rings, but this only goes back to 12,593 years ago.
The Lake Suigetsu record extends much further to 52,800 years ago, increasing the direct radiocarbon record by more than 40,000 years.
Before the publication of this new research, the longest and most important radiocarbon dating records came from such marine sediments or cave formations, but these needed to be corrected.
At last, the cores from Lake Suigetsu provide a more complete, direct record of radiocarbon from the atmosphere without the need for further correction.
For those researchers working in the field of human history, the chronology of events remains a major element of reflection.The cores are unique: they display layers in the sediment for each year, giving scientists the means of counting back the years.These counts are compared with over 800 radiocarbon dates from the preserved fossil leaves.'This record will not result in major revisions of dates.But, for example in prehistoric archaeology, there will be small shifts in chronology in the order of hundreds of years,' said Professor Ramsey.