Potassium argon dating limitations

Rated 4.67/5 based on 868 customer reviews

Absolute dating provides a numerical age or range in contrast with relative dating which places events in order without any measure of the age between events.In archaeology, absolute dating is usually based on the physical, chemical, and life properties of the materials of artifacts, buildings, or other items that have been modified by humans and by historical associations with materials with known dates (coins and written history).The potassium-argon dating method has been used to measure a wide variety of ages.The potassium-argon age of some meteorites is as old as 4,500,000,000 years, and volcanic rocks as young as 20,000 years old have been measured by this method.

Thus, the ratio of argon-40 and potassium-40 and radiogenic calcium-40 to potassium-40 in a mineral or rock is a measure of the age of the sample.Potassium-Argon Dating Potassium-Argon dating is the only viable technique for dating very old archaeological materials.Geologists have used this method to date rocks as much as 4 billion years old.Techniques include tree rings in timbers, radiocarbon dating of wood or bones, and trapped charge dating methods such as thermoluminescence dating of glazed ceramics.Coins found in excavations may have their production date written on them, or there may be written records describing the coin and when it was used, allowing the site to be associated with a particular calendar year.

Leave a Reply