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.
With sensitive instrumentation, this range can be extended to 70,000 years.
In addition to the radiocarbon dating technique, scientists have developed other dating methods based on the transformation of one element into another.
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.
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.
Eventually, the entire ecosystem (community of plants and animals) of the planet, including humans, is filled with a concentration of carbon-14.
As long as an organism is alive, the supply of carbon-14 is replenished.
Relative dating methods are used to determine only if one sample is older or younger than another.
Absolute dating methods are used to determine an actual date in years for the age of an object.
Dating techniques are procedures used by scientists to determine the age of an object or a series of events.