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
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).
percent modern carbon corresponds
to a computed age of 57,000