Scientists use a technique called radiometric dating to estimate the ages of rocks, fossils, and the earth.Many people have been led to believe that radiometric dating methods have proved the earth to be billions of years old.This has caused many in the church to reevaluate the biblical creation account, specifically the meaning of the word “day” in Genesis 1.
Note that, contrary to a popular misconception, carbon dating is not used to date rocks at millions of years old.
Before we get into the details of how radiometric dating methods are used, we need to review some preliminary concepts from chemistry.
Recall that atoms are the basic building blocks of matter.
Atoms are made up of much smaller particles called protons, neutrons, and electrons.
Protons and neutrons make up the center (nucleus) of the atom, and electrons form shells around the nucleus.
The number of protons in the nucleus of an atom determines the element.For example, all carbon atoms have 6 protons, all atoms of nitrogen have 7 protons, and all oxygen atoms have 8 protons.The number of neutrons in the nucleus can vary in any given type of atom.So, a carbon atom might have six neutrons, or seven, or possibly eight—but it would always have six protons.An “isotope” is any of several different forms of an element, each having different numbers of neutrons.The illustration below shows the three isotopes of carbon.