Carbon dating used determine age earth
Nuclear tests, nuclear reactors and the use of nuclear weapons have also changed the composition of radioisotopes in the air over the last few decades.
This human nuclear activity will make precise dating of fossils from our lifetime very difficult due to contamination of the normal radioisotope composition of the earth with addition artificially produced radioactive atoms.
Knowledge of radioactivity helps them understand how rocks can be dated, which helps them appreciate the scale of geologic time…
Scientific evidence indicates that some rock layers are several billion years old.
When scientists first began to compare carbon dating data to data from tree rings, they found carbon dating provided "too-young" estimates of artifact age.
This restriction extends to animals that consume seafood in their diet.
Carbon-14 cannot be used to date biological artifacts of organisms that did not get their carbon dioxide from the air.
This rules out carbon dating for most aquatic organisms, because they often obtain at least some of their carbon from dissolved carbonate rock.
______________________________________________________________ ____________________________________________________________________ ____________________________________________________________________________________________ _______________________________________________________________ Relative Ages of Rocks: WIki Books (Wiki Books: A project hosted by the Wikimedia Foundation for the creation of free content textbooks) Willard Libby and Radiocarbon Dating.
American Chemical Society A Framework for K-12 Science Education: Practices, Crosscutting Concepts, and Core Ideas (2012), from the National Research Council of the National Academies. Radioactive decay lifetimes and isotopic content in rocks provide a way of dating rock formations and thereby fixing the scale of geological time.