Half life dating rocks
The half-life refers to the amount of time it takes for half the radiocarbon in a sample of bone or shell or any carbon sample to disappear.
Libby found that it took 5568 years for half the radiocarbon to decay.
During the period of a plant's life, the plant is taking in carbon dioxide through photosynthesis, which is how the plant makes energy and grows.
Animals eat plants, and some eat other animals in the food chain.
They thought that sites which had the same kinds of pots and tools would be the same age.
The C14 method has been and continues to be applied and used in many, many different fields including hydrology, atmospheric science, oceanography, geology, palaeoclimatology, archaeology and biomedicine.
All plants and animals on Earth are made principally of carbon.
The job of a radiocarbon laboratory is to measure the remaining amounts of radiocarbon in a carbon sample.
This is very difficult and requires a lot of careful work to produce reliable dates.