The Uranium–Lead (U–Pb) method in zircons is a geochronological technique used to determine the age of rock formation and geological events with extremely high precision.
It is one of the most important and reliable methods in the geosciences.
Radioactive uranium slowly decays into lead through known radioactive decay chains, the main ones being ²³⁸U and ²³⁵U.
By analyzing how much uranium remains and how much radiogenic lead was produced in the crystal, its age can be determined.
The U–Pb method can date:
Ages can range from a few million to more than 4,000 million years.
The most common techniques are:
U–Pb in zircons allows us to determine: