It is one of several radiometric dating techniques exploiting the uranium radioactive decay series, in which 238U undergoes 14 alpha and beta decay events on the way to the stable isotope 206Pb. Other dating techniques using this decay series include uranium–thorium dating and uranium–lead dating.

Is uranium-238 used for dating?

Uranium-234–uranium-238 dating, method of age determination that makes use of the radioactive decay of uranium-238 to uranium-234; the method can be used for dating of sediments from either a marine or a playa lake environment.

Why is uranium-238 good for dating the age of the Earth?

The long half-life of uranium-238 makes it possible to date only the oldest rocks. Although the half-life of rubidium-87 is even longer than uranium-238 (49 billion years or 10 times the age of the earth), it is useful because it can be found in almost all igneous rocks.

How uranium can be used for geological dating?

Each radioactive isotope has a known, fixed rate of decay. As its name suggests, uranium-series dating uses the radioactive decay of uranium to calculate an age. When uranium decays, it goes through a series of decays until it eventually reaches a stable isotope. These two parent isotopes have different decay chains.

How an isotope of uranium can be used to date the age of the Earth?

For example, about 1.5 percent of a quantity of Uranium 238 will decay to lead every 100 million years. By measuring the ratio of lead to uranium in a rock sample, its age can be determined. Using this technique, called radiometric dating, scientists are able to see back in time.

Why is U 235 better than u-238?

U- 235 is a fissile isotope, meaning that it can split into smaller molecules when a lower-energy neutron is fired at it. U- 238 has an even mass, and odd nuclei are more fissile because the extra neutron adds energy - more than what is required to fission the resulting nucleus.