Describe one method of relative dating
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.
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.The age of the remains of plants, animals, and other organic material can be determined by measuring the amount of carbon-14 contained in that material.Carbon-14, a radioactive form of the element carbon, is created in the atmosphere by cosmic rays (invisible, high-energy particles that constantly bombard Earth from all directions in space).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.Dating techniques are procedures used by scientists to determine the age of an object or a series of events.
The two main types of dating methods are relative and absolute.
By measuring the amount of original and transformed atoms in an object, scientists can determine the age of that object.
Cosmic rays: Invisible, high-energy particles that constantly bombard Earth from all directions in space.
Dendrochronology: Also known as tree-ring dating, the science concerned with determining the age of trees by examining their growth rings.
Half-life: Measurement of the time it takes for one-half of a radioactive substance to decay.
Absolute dates must agree with dates from other relative methods in order to be valid.