For high school and college students, and their instructors, this two-volume set presents 150 signed essays, arranged alphabetically. Each essay occupies about four pages and is structured with a brief initial summary, principal terms, clear subheadings, an annotated bibliography, and cross references. In the front matter is a listing of entries according to the following themes: continents and continental processes, crustal and surface features, earth history and stratigraphy, eruptions, geomorphology, glacial geology, mountains and mountain ranges, oceanic crust, paleontology and the fossil record, and volcanology and volcanic processes. Indexing is in the second volume along with a glossary, a bibliography, and some information in tables. Editor David K. Elliot is affiliated with Northern Arizona U. Annotation ©2012 Book News, Inc., Portland, OR (booknews.com)