The complete "Paleontology and Dinosaurs" module takes approximately four weeks to teach. " activity is a 30-minute introduction to geologic time.INTRODUCTION Scientists have good evidence that the earth is very old, approximately four and one-half billion years old.Determining the Age of Rocks and Fossils, University of California, Berkeley. This 9-12-grade activity introduces students to age dating with exercises using relative and absolute dating. Links to various activities and lesson plans concerning relative and absolute dating. Content information about absolute and relative dating methods used by the U.
Scientists also use direct evidence from observations of the rock layers themselves to help determine the relative age of rock layers.
The idea of radioactive decay and half lives, a type of absolute dating, is shown through an activity using M&M's candy and graph paper. Sequencing Time, University of California, Berkeley. This 5-12-grade activity lets students place parts of their own life story into a time line so that they can better understand how geologic time is reconstructed by scientists.
Who's on First, University of California, Berkeley. This website is a book chapter about geologic time. This online version of their informative booklet contains short, content explanations about relative time, major geologic time divisions, index fossils for use in age dating, radiometric dating and the age of the earth.
On a larger scale, even between continents, fossil evidence can help in correlating rock layers.
The Law of Superposition, which states that in an undisturbed horizontal sequence of rocks, the oldest rock layers will be on the bottom, with successively younger rocks on top of these, helps geologists correlate rock layers around the world.