What is uranium 238 used for dating rocks

By comparing how much carbon-14 there is in the dead organism with the amount in a living one, the age of the dead organism can be estimated.The half-life of uranium-238 is 4500 million years.Each of them typically exists in igneous rock, or rock made from cooled magma.Fossils, however, form in sedimentary rock -- sediment quickly covers a dinosaur's body, and the sediment and the bones gradually turn into rock.Radiometric dating is also used to date archaeological materials, including ancient artifacts.Different methods of radiometric dating vary in the timescale over which they are accurate and the materials to which they can be applied.The dating method is usually performed on the mineral zircon.

what is uranium 238 used for dating rocks-72what is uranium 238 used for dating rocks-77what is uranium 238 used for dating rocks-39

To determine the ages of these specimens, scientists need an isotope with a very long half-life.The amount of carbon-14 in the atmosphere has not changed in thousands of years.Even though it decays into nitrogen, new carbon-14 is always being formed when cosmic rays hit atoms high in the atmosphere.Among the best-known techniques are radiocarbon dating, potassium-argon dating and uranium-lead dating.By allowing the establishment of geological timescales, it provides a significant source of information about the ages of fossils and the deduced rates of evolutionary change.

What is uranium 238 used for dating rocks