A subset of the National Coal Resources Data System. Contains published coal-resource estimates for coal bearing states listed by state, county, coal field, geologic age, and formation, rank, coal thickness, and overburden thickness. Data sources and reliability are included. Full description.

This web site is an on-line warehouse of maps of the United States. For each state there are maps and images local to the site, and links to external web sites. Currently the following maps are available for most of the states: a shaded relief topographic map optimized to show the landforms; a map showing counties in a state; a black and white version of the shaded relief map; National Oceanic and ... Full description.

This site is the home page of the laboratory. Users may click to find descriptions of the Coastal Research Program which focuses on two key areas of coastal geology: the process-response systems of beaches, inlets, and tidal sand bodies; and the Holocene history and development of coastal barrier systems. Research projects are primarily concentrated on the west coast of Florida, with some projects ... Full description.

This web site is one of the world's largest online databases, providing access to a vast store of aerial photographs and digitized topographical maps of the United States, provided by the U. S. Geological Survey (USGS). TerraServer is designed to work with commonly available computer systems and web browsers over slow speed communications links. You can visit your own neighborhood or take a look at ... Full description.

The Island Information web site provides numerous facts and figures about the earth's islands. Island data is organized into the following categories: island superlatives, principal world islands and groups, 100 largest islands of the world, largest islands by continent, largest islands of selected countries, 35 largest islands of the United States, largest islands of selected U.S. states, 38 largest ... Full description.

This is a tool for converting degrees, minutes and seconds of latitude or longitude into decimal degrees, and vice-versa. It also gives the conversion formula, so users can try it themselves. Full description.

This resource describes what a topographic map is, how to read them, and what the symbols shown on maps and their legends mean. Contour lines, intervals, depth curves, and color meanings are discussed. There is also a legend showing examples of each symbol by category: elevation, boundaries, land surface features (mines, vegetation), water features (reefs, channels), buildings and related features ... Full description.

Using surveys and topographic maps, the United States Geological Survey (USGS) has determined distances between points and elevations of features, and put them into a data format at this website. Elevations of the 50 largest cities, highest and lowest points in each state, summits over 14,000 feet, summits east of the Rocky Mountains, geographic centers of each state, length of US boundaries, and ... Full description.

This website is a fact sheet of the United States Geological Survey's (USGS) Mapping Applications Center. It explains, with examples, why map scales are necessary, what they do, and how they work. It also discusses common scales that the USGS uses on their topographic maps. Full description.

This web-tool calculates the great circle distance between two points on the Earth's surface. Users enter the latitude and longitude of two locations in degrees, minutes, and seconds, and the tool calculates the distance in kilometers and miles between the two points. Full description.