What is radioactive carbon dating crete greece dating
Because the cosmic ray bombardment is fairly constant, there’s a near-constant level of carbon-14 to carbon-12 ratio in Earth’s atmosphere.
Organisms at the base of the food chain that photosynthesize – for example, plants and algae – use the carbon in Earth’s atmosphere.
Before we get into the details of how radiometric dating methods are used, we need to review some preliminary concepts from chemistry.
Recall that atoms are the basic building blocks of matter.
A detailed description of radiocarbon dating is available at the Wikipedia radiocarbon dating web page.
Bottom line: Radiocarbon dating is a technique used by scientists to learn the ages of biological specimens from the distant past.
On the other hand, atmospheric testing of nuclear weapons during the 1950s and 1960s is likely to have increased the Carbon 14 content of the atmosphere.
It can be used on objects as old as about 62,000 years. Atoms of the same element that have different numbers of neutrons are called isotopes. Most carbon on Earth exists as the very stable isotope carbon-12, with a very small amount as carbon-13.
Plants and animals absorb both C-12 and C-14 in the course of their natural lifetimes simply by carrying out these basic functions.
When they die, they cease to consume them, and the isotope of C-14 begins to revert back to its Nitrogen state at an exponential rate due to its radioactive decay.
This property makes it especially useful in a process known as “radiocarbon dating”, or carbon dating for short.
Radiocarbon enters the biosphere through natural processes like eating and breathing.
Here on Earth, Carbon is found in the atmosphere, the soil, the oceans, and in every living creature. C-12, so-named because it has an atomic weight of 12 – is the most common isotope, but it is by no means the only one.