Similarly, pollen grains released by seed-bearing plants became fossilized in rock layers. If a certain kind of pollen is found in an archaeological site, scientists can check when the plant that produced that pollen lived to determine the relative age of the site.
Absolute dating methods are carried out in a laboratory. Absolute dates must agree with dates from other relative methods in order to be valid. The most widely used and accepted form of absolute dating is radioactive decay dating. Radioactive decay refers to the process in which a radioactive form of an element is converted into a nonradioactive product at a regular rate. 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. Hence the term radioactive decay. Each element decays at its own rate, unaffected by external physical conditions. By measuring the amount of original and transformed atoms in an object, scientists can determine the age of that object. Invisible, high-energy particles that constantly bombard Earth from all directions in space. Also known as tree-ring dating, the science concerned with determining the age of trees by examining their growth rings. Measurement of the time it takes for one-half of a radioactive substance to decay.
The predictable manner in which a population of atoms of a radioactive element spontaneously disintegrate over time. Study of layers of rocks or the objects embedded within those layers.
Dating Techniques | jemlasiconfo.cf
The age of the remains of plants, animals, and other organic material can be determined by measuring the amount of carbon contained in that material. Carbon, 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.
When carbon falls to Earth, it is absorbed by plants. These plants are eaten by animals who, in turn, are eaten by even larger animals. Eventually, the entire ecosystem community of plants and animals of the planet, including humans, is filled with a concentration of carbon As long as an organism is alive, the supply of carbon is replenished.