Continuous series of tree - ring dated wood samples have been obtained for roughly the past 10,000
years which give the approximate correct
radiocarbon age, demonstrating the general validity of the conventional
radiocarbon dating technique.Several long tree - ring chronologies have been constructed specifically for use in
calibrating the
radiocarbon time scale.Some may have mistaken this to mean that the sample had been dated to 20,000
radiocarbon years.The second characteristic of the measurement of
radiocarbon is that it is easy to contaminate a sample which contains very little
radiocarbon with enough
radiocarbon from the research environment to give it an apparent
radiocarbon age which is much less than its actual
radiocarbon age.