So, we start out with two isotopes of uranium that are unstable and radioactive.They release radiation until they eventually become stable isotopes of lead.All rocks and minerals contain tiny amounts of these radioactive elements.Radioactive elements are unstable; they breakdown spontaneously into more stable atoms over time, a process known as radioactive decay.Any dead material incorporated with sedimentary deposits is a possible candidate for carbon-14 dating.Radiometric dating has been used to determine the ages of the Earth, Moon, meteorites, ages of fossils, including early man, timing of glaciations, ages of mineral deposits, recurrence rates of earthquakes and volcanic eruptions, the history of reversals of Earth's magnetic field, and many of other geological events and processes.The methods work because radioactive elements are unstable, and they are always trying to move to a more stable state. This process by which an unstable atomic nucleus loses energy by releasing radiation is called radioactive decay.The thing that makes this decay process so valuable for determining the age of an object is that each radioactive isotope decays at its own fixed rate, which is expressed in terms of its half-life.
So, we rely on radiometric dating to calculate their ages.So, if you know the radioactive isotope found in a substance and the isotope's half-life, you can calculate the age of the substance. Well, a simple explanation is that it is the time required for a quantity to fall to half of its starting value.So, you might say that the 'full-life' of a radioactive isotope ends when it has given off all of its radiation and reaches a point of being non-radioactive.Radioactive decay occurs at a constant rate, specific to each radioactive isotope.Since the 1950s, geologists have used radioactive elements as natural "clocks" for determining numerical ages of certain types of rocks. "Forms" means the moment an igneous rock solidifies from magma, a sedimentary rock layer is deposited, or a rock heated by metamorphism cools off.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.As a member, you'll also get unlimited access to over 70,000 lessons in math, English, science, history, and more.Plus, get practice tests, quizzes, and personalized coaching to help you succeed.It's this resetting process that gives us the ability to date rocks that formed at different times in earth history.A commonly used radiometric dating technique relies on the breakdown of potassium (Ar in an igneous rock can tell us the amount of time that has passed since the rock crystallized.