Dating organic material
These include the uranium-thorium method, the potassium-argon method, and the rubidium-strontium method. Thermoluminescence (pronounced ther-moeloo-mi-NES-ence) dating is very useful for determining the age of pottery.When a piece of pottery is heated in a laboratory at temperatures more than 930°F (500°C), electrons from quartz and other minerals in the pottery clay emit light.By measuring the amount of carbon-14 remaining, scientists can pinpoint the exact date of the organism's death.The range of conventional radiocarbon dating is 30,000 to 40,000 years.The nucleus of every radioactive element (such as radium and uranium) spontaneously disintegrates over time, transforming itself into the nucleus of an atom of a different element.In the process of disintegration, the atom gives off radiation (energy emitted in the form of waves). Each element decays at its own rate, unaffected by external physical conditions.Dendrochronology: Also known as tree-ring dating, the science concerned with determining the age of trees by examining their growth rings.
Using thermoluminescence, pottery pieces as old as 100,000 years can be dated with precision. Known as dendrochronology (pronounced den-dro-crow-NOL-o-gee), tree-ring dating is based on the fact that trees produce one growth ring each year.When carbon-14 falls to Earth, it is absorbed by plants.These plants are eaten by animals who, in turn, are eaten by even larger animals.Radioactive decay: The predictable manner in which a population of atoms of a radioactive element spontaneously disintegrate over time.Stratigraphy: Study of layers of rocks or the objects embedded within those layers.