Closure temperature

Closure temperature

In radiometric dating, closure temperature or blocking temperature is an idea that helps scientists learn when rocks and minerals formed. It is the temperature at which a mineral cools enough that certain atoms inside it stop moving. These atoms, called isotopes, can tell us the age of the rock or mineral.

The idea of closure temperature was first explained in a paper by Martin H. Dodson in 1973, and other scientists have added to our understanding since then. Different minerals have different closure temperatures.

Scientists can find out the closure temperature in a lab by heating up samples of minerals and then letting them cool. As the mineral cools, its structure changes, and at a certain temperature, the atoms stop moving. This temperature is the blocking temperature.

Closure temperatures are useful in geochronology and thermochronology. They help scientists date events and understand how quickly things happened in Earth's past.

Table of values

This table shows the closing temperatures of different materials. These temperatures are estimates and might change with more study.

Potassium-argon method

Uranium-lead method

Electron spin resonance dating