Carbon dating uranium Fan dating network
Absolute dates must agree with dates from other relative methods in order to be valid.
Carbon-based compounds are the basis for all living systems and comprise the structure of fossil fuels in the form of hydrocarbons. The International Union of Pure and Applied Chemistry designated the isotope C-12 as the basis for atomic weights, while the unstable isotope C-14, with a half-life of 5700 years, is used for carbon dating.If a certain kind of pollen is found in an archaeological site, scientists can check when the plant that produced that pollen lived to determine the relative age of the site.Absolute dating methods are carried out in a laboratory.These include the uranium-thorium method, the potassium-argon method, and the rubidium-strontium method. Thermoluminescence (pronounced ther-moeloo-mi-NES-ence) dating is very useful for determining the age of pottery.When a piece of pottery is heated in a laboratory at temperatures more than 930°F (500°C), electrons from quartz and other minerals in the pottery clay emit light.