Radiometric dating a christian perspective by dr roger c wiens dating site for the unpopular
There are now well over forty different radiometric dating techniques, each based on a different radioactive isotope.Most dating techniques involve multiple tests using different methods and on different minerals within a rock (isochrons).This works because if there were no rubidium-87 in the sample, the strontium composition would not change.The slope of the line is used to determine the age of the sample.Atoms of a radioactive nuclide decays exponentially at a rate described by a parameter known as the half-life, usually given in units of years when discussing dating techniques.After one half-life has elapsed, one half of the atoms of the nuclide in question will have decayed into a “daughter” nuclide or decay product.The solid line drawn through the samples will thus progressively rotate from the horizontal to steeper and steeper slopes.
It’s such an important topic that I did not want to shoehorn it into the last lesson. The discussion today will be taken from Radiometric Dating – A Christian Perspective by Dr. Radiometric dating (often called radioactive dating) is a technique used to date materials such as rocks, usually based on a comparison between the observed abundance of a naturally occurring radioactive isotope and its decay products, using known decay rates.
All ordinary matter is made up of combinations of chemical elements, each with its own atomic number, indicating the number of protons in the atomic nucleus.
Additionally, elements may exist in different isotopes, with each isotope of an element differing in the number of neutrons in the nucleus.
My reason for giving it is (1) to be precise and complete and (2) to show you that the math is in fact simple algebra. Let’s say we are going to date a rock using the Rubidium-Strontium method. When a rock cools, all its minerals have the same ratio of strontium-87 to strontium-86, though they have varying amounts of rubidium.
As long as a lab can analyze the amount of parent isotope and daughter isotope, the amount of original daughter isotope can be calculated and the age of the rock from when it cooled from the last time it was molten can be calculated. Rubidium-87 decays to strontium-87 with a half-life of 48.8 million years; so it is a good method to date older rocks. As the rock ages, the rubidium decreases by changing to strontium-87, as shown by the dotted arrows.