those that form during chemical reactions without breaking down).
The unstable or more commonly known radioactive isotopes break down by radioactive decay into other isotopes.
The rate of decay (given the symbol λ) is the fraction of the 'parent' atoms that decay in unit time.
For geological purposes, this is taken as one year.
Each atom is thought to be made up of three basic parts.
The nucleus contains protons (tiny particles each with a single positive electric charge) and neutrons (particles without any electric charge).
Perhaps you have heard of Ice Man, a man living in the Alps who died and was entombed in glacial ice until recently when the ice moved and melted.
The atoms of each element may vary slightly in the numbers of neutrons within their nuclei.Find additional lessons, activities, videos, and articles that focus on relative and absolute dating.The technique of comparing the abundance ratio of a radioactive isotope to a reference isotope to determine the age of a material is called radioactive dating.Radioactive dating is a method of dating rocks and minerals using radioactive isotopes.This method is useful for igneous and metamorphic rocks, which cannot be dated by the stratigraphic correlation method used for sedimentary rocks. Some do not change with time and form stable isotopes (i.e.