Radiometric dating sedimentary rock Raven riley webcam online live
The half-life of this decay is 11.93 billion years.
The samples are crushed to sand and granule size, thoroughly mixed to homogenise the material and a smaller subsample selected.
In cases where particular minerals are to be dated, these are separated from the other minerals by using heavy liquids (liquids with densities similar to that of the minerals) in which some minerals will float and others sink, or magnetic separation using the different magnetic properties of minerals.
The amount of deflection will depend upon the atomic mass of the particles so different isotopes are separated by their different masses.
Detectors at the end of the tube record the number of charged particles of a particular atomic mass and provide a ratio of the isotopes present in a sample.
Radiometric dating of minerals in metamorphic rocks usually indicates the age of the metamorphism.