Radioactive isotopes used for dating
Radiocarbon dating is one kind of radiometric dating, used for determining the age of organic remains that are less than 50,000 years old.For inorganic matter and for older materials, isotopes of other elements, such as potassium, uranium, and strontium, are used.The amount of the isotope in the object is compared to the amount of the isotope's decay products.The object's approximate age can then be figured out using the known rate of decay of the isotope.Radioactive isotopes have a variety of applications.Generally, however, they are useful because either we can detect their radioactivity or we can use the energy they release.
A is a substance that can be used to follow the pathway of that substance through some structure.
These ions are accelerated in an electric field through collimating slits and subject to a magnetic field which causes the ions to follow a curved path. By adjustment of the strength of the magnetic field and suitable placement of an ion collector, the different isotopes can be measured with precision.
There are some things that affect these measurements.
Simply counting the number of rings will give one a fairly good idea of the age of the tree.
Periods of heavy rain and lots of sunshine will make larger gaps of growth in the rings, while periods of drought might make it difficult to count individual rings. When a given quantity of an isotope is created (in a supernovae, for example), after the half-life has expired, 50% of the parent isotope will have decomposed into daughter isotopes.