Carbon 14 dating organic material
Rates of radiocarbon production vary through time, in a quasi-periodic manner. It is therefore necessary to distinguish between radiocarbon years ( against a chronology of calendar years.
Thus, it is possible (and, given the Flood, probable) that materials which give radiocarbon dates of tens of thousands of radiocarbon years could have true ages of many fewer calendar years. The shells of live freshwater clams have been radiocarbon dated in excess of 1600 years old, clearly showing that the radiocarbon dating technique is not valid.
The shells of live freshwater clams can, and often do, give anomalous radiocarbon results.
This carbon is therefore present in their bodies and bones.
Upon death, no more C means that it does not work for organisms that died after about 40,000 years ago. Palaeoglaciology of the Alexander Island ice cap, western Antarctic Peninsula, reconstructed from marine geophysical and core data.
The problem with freshwater clams arises because these organisms derive the carbon atoms which they use to build their shells from the water in their environment.