The Central Region's Mineral Resource Surveys Understanding Our Planet Through Chemistry Web site shows how chemists and geologists use analytical chemistry to determine the age of the Earth. The various topics covered include: elements, isotopes, and radioactivity; global change in the geologic past; cleaning up coal burning; and mapping stream sediments for resource exploration, among others....

The University of California-Berkeley Museum of Paleontology (last mentioned in the June 16, 1995 Scout Report) has recently updated its Web Geologic Time Scale, an online feature that helps users learn about the geologic timeline and explore related museum exhibits. The familiar geologic timeline appears on the main page of the Web site, with hypertext links for each division of time. Every page...