Types of radioactive dating methods
If the rock containing these minerals is heated, the tracks will begin to disappear.If the rock is heated high enough, 120C for apatite, all tracks will disappear.By measuring the C concentration or residual radioactivity of a sample whose age is not known, it is possible to obtain the number of decay events per gram of Carbon.By comparing this with modern levels of activity (1890 wood corrected for decay to 1950 AD) and using the measured half-life it becomes possible to calculate a date for the death of the sample. As a result of atomic bomb usage, C ages of objects younger than 1950.
U-Pb geochronology of is used for determining the age of emplacement of igneous rocks of all compositions, ranging in age from Tertiary to Early Archean.
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.
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 should also be applied only to minerals that remained in a closed system with no loss or gain of the parent or daughter isotope.