Giem [18] reviewed the literature and tabulated about seventy reported AMS measurements of 14C in organic materials from the geologic record that, according to the conventional geologic time-scale, should be 14C ‘dead.’ The surprising result is that organic samples from every portion of the
fossil record show detectable amounts of 14C. For the measurements considered most reliable, the 14C/C ratios appear to fall in the range 0.1-0.5 percent of the modern 14C/C ratio (percent modern carbon, or pmc).
0.1 percent modern carbon corresponds to a computed age of 57,000 years!