Planet Earth: An Introduction to Earth Sciences - Online text by Roger N. Anderson of Columbia University. Covers origins of the earth and life, plate tectonics, and formation and deformation of continents. - http://www.ldeo.columbia.edu/res/pi/4d4/planet/
Earth Science World - American Geological Institute resources for teachers and students. Includes searchable database of earth images, geologic time scale, and interactive features. - http://www.earthscienceworld.org
Geography Site: Physical Geography - Illustrated descriptions and explanations of earthquakes, plate tectonics, glaciers and glacial landforms, and volcanoes and volcanic deposits, intended for students up to age 16, but suitable for a wider audience. - http://www.geography-site.co.uk/pages/physical.html
Strata: William Smith on the Web - Publications of the father of modern geology, who first drew a chart of the strata under the surface of the earth. Printable version of Smith's famous geologic map of England. - http://www.unh.edu/esci/wmsmith.html
Wieczorek, Jozef - Research on the geology of the Tatra mountains and other publications by this researcher. - http://www.geo-jwieczorek.ans.pl/
Evolving Earth Foundation - Earth science and natural science resources, articles and online education. - http://www.evolvingearth.org/
Walter Geology Library - Listing of virtual and on-line geologic field trip guidebooks. - http://www.lib.utexas.edu/geo/onlineguides.html
Photo Geo Gallery - Image gallery of European geology. - http://www.fotogeo-jwieczorek.ans.pl/
Geoscapes Photography - Geologic and natural history landscape photography of the western United States and Pacific islands. - http://www.geoscapesphotography.com/
Pangaea - An information system aimed at archiving, publishing and distributing data from global change research with special emphasis on geological, marine and environmental sciences. - http://www.pangaea.de/