What is the difference between radiological and relative dating
Argon is gas that gradually builds up within rocks from the decay of radioactive potassium.It is initially formed in the molten rock that lies beneath the Earth’s crust.Only one sample is required for this method as both the argon-39 and argon-40 can be extracted from the same sample.In special cases, bones can be compared by measuring chemicals within them.Knowing when a dinosaur or other animal lived is important because it helps us place them on the evolutionary family tree.
Argon then starts to re-accumulate at a constant rate in the newly formed rock that is created after the eruption.This relatively new technique was developed in order to achieve more accurate dates than those obtained from the potassium-argon method.The older method required two samples for dating and could produce imprecise dates if the argon was not fully extracted.Instead, other methods are used to work out a fossil’s age.
These include radiometric dating of volcanic layers above or below the fossils or by comparisons to similar rocks and fossils of known ages.
This form of uranium usually decays into a stable lead isotope but the uranium atoms can also split – a process known as fission.