For this geologic time worksheet, students review how fossils were formed and the events that mark the various geological eras and periods. This worksheet has 10 fill in the blank and 9 short answer questions.

This is a nice explanation of geologic time and Earth's major eras. Although this site is designed for younger students, it is mostly text with few images.

A comprehensive timeline of events in the prehistory and history of Ohio. Hyperlinks to the multitude of specific articles about Ohio's history.

An extensive biography of William Morris Davis (1850-1934 CE), often called "The father of American geography." He was one of the founders of the Association of American Geographers and a regular contributor to the National Geographic...

Earth's magnetic poles have reversed themselves throughout its long history. Find out what scientists know about these reversals. A geologic time line shows when the reversals occurred.