First use of radiocarbon dating sasha cohen skater dating
These values should correspond exactly to normal historical years BC and AD.
The term cal BP means the number of years before 1950 and can be directly compared to calendar years.
This is very useful as a record of the radiocarbon concentration in the past.The pair of blue curves show the radiocarbon measurements on the tree rings (plus and minus one standard deviation) and the red curve on the left indicates the radiocarbon concentration in the sample.The grey histogram shows possible ages for the sample (the higher the histogram the more likely that age is).Radiocarbon measurements are always reported in terms of years `before present' (BP).
This figure is directly based on the proportion of radiocarbon found in the sample.To give an example if a sample is found to have a radiocarbon concentration exactly half of that for material which was modern in 1950 the radiocarbon measurement would be reported as 5568 BP.