Definition of word from the Merriam-Webster Online Dictionary with audio pronunciations, thesaurus, Word of the Day, and word games.

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The National Geophysical Data Center (NGDC) is part of the US Dept of Commerce, National Oceanic & Atmospheric Administration, National Environmen...

This web site of Steve Reynolds, geology professor at Arizona State University, contains numerous color photographs, 3D perspectives, and informatio...

The best online resource for topographic (topo) maps and high-resolution aerial photos covering all of the United States (U.S.) and Canada.

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Shuttle Radar Topography Mission, Mapping the World in 3-D

State of Michigan - State of Michigan

IOPscience is a unique platform for IOP-hosted journal content providing site-wide electronic access to more than 130 years of leading scientific rese...