Re: carbon 14, potassium-argon

Bterr (
19 Oct 1996 15:57:53 -0400

It's been nearly 30 years since I taught archaeology. However, C14 is
based on radioactive decay of C14 to C12organic material. The most useful
range with C14 is approximately 4-50,000 years BP, although there now may
be some more advanced methods of analysis that push the date back farther.
K/Ar is based on radioactive decay in igneous rocks of volcanic origin
and, as I remember, it's most useful range was about 1-3 million years BP.
C-14 is most useful for dating finds that concern Homo Sapiens, Sapiens
and Neanderthalensis. K/Ar for early Homo Erectus and Homo Habilis. A
freshman text on archaeology will give you more exacting information.