Radiocarbon dating, or carbon-14 dating, is a technique for determining the age of organic materials by measuring their carbon-14 content. Carbon-14 is a radioactive isotope of carbon. Radiocarbon dating is possible because carbon-14 is absorbed by living organisms from the atmosphere, and when they die, they stop taking in the carbon-14 that they had previously absorbed. That means carbon-14 begins to decay at a known rate (a half-life of approximately 5,730 years), and scientists can use the remaining carbon-14 in a sample to estimate the amount of time that has passed since the organism died.
- How it works:
Living things (plants and animals) take in carbon-14 from the atmosphere during their life, but when they die, they stop taking in that carbon-14, and it decays at a known rate. The carbon-14 in organic materials can be measured to indicate the remaining amount of carbon-14, and scientists can then estimate how long ago the organism was alive. - Accuracy and limitations:
Radiocarbon dating is accurate for sample ages of approximately 50,000 – 60,000 years old. It is widely used in archaeology, geology, and other fields. Accuracy can be affected by other isotopes or other factors such as calibration. - Calibration:
Calibration is important because the amount of carbon-14 that existed in the atmosphere has not always remained the same. Calibration is done using various sources, often tree ring data or lab standards. - Applications:
Radiocarbon dating is used for a variety of applications, some include: - Archaeology: Dating artifacts, tree rings, shells, pottery shards, bones, and other organic materials related to human history.
- Geology: Dating sediments, fossils, and other geological materials.
- Environmental science: Dating the omitted days of peat bogs, ice cores, and other environmental samples.
- Forensics: Dating organic materials relevant to forensic investigations.
