Quaternary dating methods wiley
When the carbon dioxide, containing C14 as well as stable C12 and C13, is taken in by plants it is no longer exposed to the intense cosmic ray bombardment in the upper atmosphere, so the carbon 14 isotope decays without being replenished.Measuring the ratio of C14 to C12 and C13 therefore dates the organic matter for periods back to about eight half-lives of the isotope, 45,000 years.
Sabretoothed Carnivores and the Killing of Large Prey.
Master of Science Thesis, Universite des Sciences et Techniques due Languedoc.
(ed.) - Zum Ober-Bathonium (Mittlerer Jura) im Raum Hildesheim, Nordwestdeutschland.
in pocket) with fossils (ammonites, ostracods, a.o.).
Carbon 14 is created by cosmic rays in the upper atmosphere.