GEOLOGY

• Bibliography and Index of Geology. Alexandria: American Geological Institute, 1966–. A comprehensive index of more than 2.3 million bibliographic citations to articles, books, maps, papers, reports, and theses covering the geosciences internationally. This index is maintained and updated monthly by the AGI; the electronic version is called GeoRef. An earlier index of North American Geology covers publications back to 1907.

• Links for Mineralogistshttp://www.uni-wuerzburg.de/mineralogie/links.html A large directory of links to information on petrology, geochemistry, crystallography, materials science, and ore and mineral deposits. The site is maintained by Klaus-Peter Kelber at the Institute of Mineralogy, University of Würzburg.
• Minerals Informationhttp://minerals.usgs.gov/minerals Includes an online version of The Minerals Yearbook with profiles of over 90 minerals as well as international industry surveys and statistics, current and historical. From the U.S. Geological Survey.
• National Map: The Nation's Topographic Map for the 21st Centuryhttp://nationalmap.usgs.gov An amazing tool from the U.S. Geological Survey. The viewer allows users to zoom in on any part of the United States and choose map layers such as elevation, roads, water, land use, and even detailed aerial satellite images. Whether you're examining a region, a state, or a few city blocks, this tool offers access to a wealth of topographic information.
• Petroleum Engineering Reading Roomhttp://www.pge.utexas.edu/reading/info.cfm Offers digital collections of publications on petroleum worldwide as well as information about government and commercial sites and research centers. Part of the WWW Virtual Library and compiled by the Department of Petroleum and Geosystems Engineering at the University of Texas at Austin.
• Tour of Geologic Timehttp://www.ucmp.berkeley.edu/exhibits/geologictime.php A "journey through the history of the Earth," covering the history of the geologic time scale and details about each geologic era. Sponsored by the University of California Museum of Paleontology.
• U.S. Geological Surveyhttp://www.usgs.gov Since 1879, this federal project has provided the nation with geologic information and mapping services. Its Web site provides information about earthquakes, environmental and biological material, geospatial data and mapping projects, and other geologic resources.

• Encyclopedia of Earth Sciences Series. Ed. Rhodes W. Fairbridge et al. 20 vols. Boston: Kluwer Academic Publishers, 1966–99. Offers lengthy, scholarly articles on oceanography, atmospheric sciences and astrogeology, geochemistry, world regional geography, climatology, and structural geology. Each volume covers a different aspect of earth sciences.
• Encyclopedia of Paleontology. Ed. Ronald Singer. 2 vols. Chicago: Fitzroy Dearborn, 1999. Includes information on principles and methods of the field as well as on paleontologists and their findings throughout the world. Entries cover dinosaurs and other animals and plants found in the fossil record.
• Lexicon of Geologic Names of the United States (including Alaska). 2 vols. Washington: Government Printing Office, 1936. With supplements. Provides information from records kept since the 1880s by the Geological Names Committee of the U.S. Geological Survey. This work identifies the names of geological features by time period and location and provides reviews of the literature referring to the names. Supplements provide information on more recently named features. Most of the names from the print volumes are also provided online in the Geolex database: <http://ngmdb.usgs.gov/Geolex/geolex_home.html>.
• Macmillan Encyclopedia of Earth Sciences. Ed. Julius E. Dasch. 2 vols. New York: Macmillan, 1996. Offers nearly 400 accessible articles on all aspects of earth science, including solid earth, oceanographic, and atmospheric sciences, as well as some coverage of the place of the earth in the solar system.