Dating rocks and fossils and geologic events chat dating find friend new
The majority of the time fossils are dated using relative dating techniques.
Using relative dating the fossil is compared to something for which an age is already known.
So in order to date most older fossils, scientists look for layers of igneous rock or volcanic ash above and below the fossil.
Scientists date igneous rock using elements that are slow to decay, such as uranium and potassium.
For example if you have a fossil trilobite and it was found in the Wheeler Formation.
These isotopes break down at a constant rate over time through radioactive decay.
The universe is full of naturally occurring radioactive elements.
Radioactive atoms are inherently unstable; over time, radioactive "parent atoms" decay into stable "daughter atoms." When molten rock cools, forming what are called igneous rocks, radioactive atoms are trapped inside. By measuring the quantity of unstable atoms left in a rock and comparing it to the quantity of stable daughter atoms in the rock, scientists can estimate the amount of time that has passed since that rock formed.
Relative dating is used to determine a fossils approximate age by comparing it to similar rocks and fossils of known ages.
Absolute dating is used to determine a precise age of a fossil by using radiometric dating to measure the decay of isotopes, either within the fossil or more often the rocks associated with it.