Scientists calculate ages by measuring how much of the isotope remains in the substance.
Continue Reading The key to an age of a substance is the decay-product ratio.
This process begins as soon as a living thing dies and is unable to produce more carbon-14.
Plants produce carbon-14 through photosynthesis, while animals and people ingest carbon-14 by eating plants. Scientists determine the ages of once-living things by measuring the amount of carbon-14 in the material.
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.
Radioactive elements were incorporated into the Earth when the Solar System formed.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.If an igneous or other rock is metamorphosed, its radiometric clock is reset, and potassium-argon measurements can be used to tell the number of years that has passed since metamorphism.Carbon-14 is a method used for young (less than 50,000 year old) sedimentary rocks.The ratio of the original isotope and its decay product determines how many half-lives have occurred since the sample formed.A half-life measures the time it takes for one half of a radio isotope's atoms to break down into another element.and is now the principal source of information about the absolute age of rocks and other geological features, including the age of fossilized life forms or the age of the Earth itself, and can also be used to date a wide range of natural and man-made materials.Together with stratigraphic principles, radiometric dating methods are used in geochronology to establish the geologic time scale.Among the best-known techniques are radiocarbon dating, potassium–argon dating and uranium–lead dating.By allowing the establishment of geological timescales, it provides a significant source of information about the ages of fossils and the deduced rates of evolutionary change.