Radiocarbon dating is used to find the age of
After an organism dies, the radiocarbon decreases through a regular pattern of decay. The time taken for half of the atoms of a radioactive isotope to decay in Carbon-14’s case is about 5730 years.Half-lives vary according to the isotope, for example, Uranium-238 has a half-life of 4500 million years where as Nitrogen-17 has a half-life of 4.173 seconds!Radiocarbon is then taken in by plants through photosynthesis, and these plants in turn are consumed by all the organisms on the planet.So every living thing has a certain amount of radiocarbon within them.In 1949, American chemist Willard Libby, who worked on the development of the atomic bomb, published the first set of radiocarbon dates.His radiocarbon dating technique is the most important development in absolute dating in archaeology and remains the main tool for dating the past 50,000 years.
It is good for dating for the last 50,000 years to about 400 years ago and can create chronologies for areas that previously lacked calendars.Plankton absorbs, Carbon-14 from the ocean much like terrestrial plants absorb Carbon-14 from the air.Since plankton is the foundation of the marine food chain, Carbon-14 is spread throughout aquatic life.The extra neutrons in Carbon-14’s case make it radioactive (thus the term, radiocarbon).Radiocarbon is produced in the upper atmosphere after Nitrogen-14 isotopes have been impacted by cosmic radiation.
Limitations and calibration: When Libby was first determining radiocarbon dates, he found that before 1000 BC his dates were earlier than calendar dates.