Geology

• Alexandria Digital Library Gazetteer--maps, including earthquake features, craters, reefs, etc...
• American Geological Institute--includes news, a data repository, a career information center, a book center, the GeoRef system, a publications list, and more.
• Ask a Geologist-- E-mail your questions here; a geologist from the US Geological Survey will e-mail you an answer. Basic information is linked in, as is a usenet FAQ file and a list of prime geological internet sites.
• Building the Digital Earth -- by Cornell University, great interactive datasets.
• Dynamic Earth--a complete textbook on plate tectonics from the US Geological Survey.
• Earth Science World Image Bank -- great images of all sorts of land, sea and air-scapes. A great way to see what the textbooks in class are talking about! Searchable and Browsable.
• Employment Resources in the Earth Sciences
• Geoindex--a search engine for the geological professional.
• Geological Maps  -- from the US government
• Geological Time Scale Chart
• Geology and the Environment--articles
• Geosphere -- Geological Society of America's first Open Access journal - full-text.
• Geotimes--the news magazine from the American Geological Institute.
• Global Change Master Directory--from NASA, a comprehensive data source of satellite data and earth science data, to which scientists can link their own data sets.
• Global Change Research Information Office-- provides access to data and information on global environmental change research, adaptation/mitigation strategies and technologies, and global change related educational resources.
• Great Globe Gallery-- More than 60 views of the globe, complete with geological data such as digital elevation models, sea surface temperatures, el Nino, ice caps and permafrost formation, crustal boundaries and ring of fire
• Green Map System -- "locally created maps that chart the natural and cultural environment. Using adaptable tools and a shared visual language of Green Map Icons to highlight green living resources"
• Guide to Meteorology--a multimedia resource, designed for students from elementary to college age.
• Iowa Geological Survey
• Mineralogy Database--includes definitions, some images, and minerals listed by name, by crystal system, by chemical composition; also links to other minerals sites.
• National Geophysical Data Center--basic climate, geophysical and environmental data from National Oceanic and Atmospheric Administration.
• OnLine Full Text Resources in Geology -- Scroll down the page 
• A Tapestry of Time And Terrain -- The Union of Two Maps - Geology and Topography, this digital tapestry outlines the geologic story of continental collision and break-up, mountain-building, river erosion and deposition, ice-cap glaciation, volcanism, and other events and processes that have shaped the region over the last 2.6 billion years.
• This Dynamic Planet--contains "text and figures depicting volcanoes, earthquakes, impact craters, and plate tectonics located around the world, as well as a 44 inch wide world map. The text explains the geological reasoning for the distribution of volcanoes and earthquakes (shown in the figures) and the formation of impact craters"
• U.S. Geological Survey
• Virtual Geosciences Professor--a guide to online teaching resources in the geosciences. The University of Houston has kept the site running even thought it's creator has died. Uncertain if it is being properly maintained, though the listserv is still active as of 1/04.
• Web Geological Time Machine--: choose your period and read (and view) all about it.
• World-Wide Web Virtual Library-Meteorology--a comprehensive meteorology site on the web.