I. Absolute Dating Absolute dating any method of measuring the age of an event or object in years. Paleontologist can date many types of igneous rocks as well as recent organic fossils. Using Half-lives to Date Fossils

II. Radiometric Dating A. Radioactive Decay Process in which a radioactive isotope breaks down into a stable isotope of the same or another element.

II. Radiometric Dating B. Radiometric dating Scientist determine the age of an object by estimating the percentages of radioactive (parent) to stable isotopes (daughter). PBS Radiometric Dating Explanation

C. Half-life Half-life the time needed for half of a sample of radioactive substance to undergo radioactive decay.

Radioactive Decay To view this animation, click “View” and then “Slide Show” on the top navigation bar.

Using Half-lives to Date Fossils Evidence of Events in Earths history web simulation