By determining the number of tracks present on a polished surface of a grain and the amount of uranium present in the grain, it is possible to calculate how long it took to produce the number of tracks preserved.As long as the mineral has remained cool, near the earth surface, the tracks will accumulate.This method dates the formation or time of crystallisation of the mineral that is being dated; it does not tell when the elements themselves were formed.
Geological Time | Geologic Time Scale | Plate Tectonics | Radiometric Dating | Deep Time | Geological History of New Zealand | Radiometric Dating Radiometric measurements of time Since the early twentieth century scientists have found ways to accurately measure geological time.
The discovery of by the French physicist, Henri Becquerel, in 1896 paved the way of measuring absolute time.
Zircons will loose their tracks at higher temperatures of 200.
The tracks will then begin to accumulate when the rock begins to cool.
Shortly after Becquerel's find, Marie Curie, a French chemist, isolated another highly radioactive element, .
The realisation that radioactive materials emit rays indicated a constant change of those materials from one element to another.
Here are some of the materials that can be successfully dated using this method: Potassium-Argon Dating Potassium-Argon (K-Ar) dating is the most widely applied technique of radiometric dating.
Potassium is a component in many common minerals and can be used to determine the ages of igneous and metamorphic rocks.
U-Pb ages of metamorphic minerals, such as zircon or monazite are used to date thermal events, including terrestrial meteoritic impacts.