Carbon dating explanation
However, in either case, the background beta radiation has to be compensated for, and, in the older objects, the amount of C-14 they have left is less than the margin of error in measuring background radiation. Question: Creationists such as Cook (1966) claim that cosmic radiation is now forming C-14 in the atmosphere about one and one-third times faster than it is decaying.
When the organisms die, they stop incorporating new C-14, and the old C-14 starts to decay back into N-14 by emitting beta particles.Of course, species of tree tend to produce two or more growth rings per year.But other species produce scarcely any extra rings.Carbon from these sources is very low in C-14 because these sources are so old and have not been mixed with fresh carbon from the air.Thus, a freshly killed mussel has far less C-14 than a freshly killed something else, which is why the C-14 dating method makes freshwater mussels seem older than they really are.
ICR creationists claim that this discredits C-14 dating. Answer: It does discredit the C-14 dating of freshwater mussels, but that's about all.