As radioactive Parent atoms decay to stable daughter atoms (as uranium decays to lead) each disintegration results in one more atom of the daughter than was initially present and one less atom of the parent.The probability of a parent atom decaying in a fixed period of time is always the same for all atoms of that type regardless of temperature, pressure, or chemical conditions. The time required for one-half of any original number of parent atoms to decay is the half-life, which is related to the decay constant by a simple mathematical formula.Most people think that radioactive dating has proven the earth is billions of years old.Yet this view is based on a misunderstanding of how radiometric dating works.Radioactivity was discovered in 1896 by French physicist Henri Becquerel.By 1907 study of the decay products of uranium (lead and intermediate radioactive elements that decay to lead) demonstrated to B. Boltwood that the lead/uranium ratio in uranium minerals increased with geologic age and might provide a geological dating tool.There's a small amount of radioactive carbon-14 in all living organisms.When they die no new carbon-14 is taken in by the dead organism.
Paleontology seeks to map out how life evolved across geologic time.
All rocks and minerals contain long-lived radioactive elements that were incorporated into Earth when the Solar System formed.
These radioactive elements constitute independent clocks that allow geologists to determine the age of the rocks in which they occur.
It is based on a comparison between the observed abundance of a naturally occurring radioactive isotope and its decay products, using known decay rates.
It is the principal source of information about the absolute age of rocks and other geological features, including the age of the Earth itself, and it can be used to date a wide range of natural and man-made materials.
In many cases, the daughter nuclide is radioactive, resulting in a decay chain.