Ask USGS - U.S. Geological Survey's information resource. Mineralogy - List of minerals according to chemical formulas and classes. EurekAlert Reference Desk links to a variety of online ready reference tools. Illustrated Glossary of Geology is an alphabetical list of basic geologic terms. Martindale's Reference Desk is a collection of ready reference sources from all disciplines.
Earth resources observation systems.
Without Walls - University of California Museum of Paleontology online exhibits. Plate Tectonics - Animations of continental drift based on paleogeographic maps by Christopher Scotese of UT Arlington. The Virtual Geosciences Professor - A collection of online courses.