Key Earth Science Links
Maps (Topographic and Geologic)
Geologic Maps, American Geosciences Institute. Website to accompany their popular publication, "Meeting Challenges with Geologic Maps." Explains scales and symbols of maps, how geologic maps are made, their value, and what they are used for. PDF versions of parts of the publication showing how geologic maps are used with examples from around the United States are offered online.
What's a Topographic Map. U.S. Geological Survey. Provides easy-to-understand explanation of topographic maps, types of topographic map information, including a fact sheet about map scales, and a key to symbols used on topographic maps in the United States. Free teacher packets for map exercises are also available online. Map Adventures contains seven lessons about map legends, scales, and grids appropriate for grades K-3. What Do Maps Show? contains four lessons about topographic maps, appropriate for grades 5-8. Exploring Maps contains four lessons to improve map-reading skills and shows how maps can be used to answer fundamental geographic questions; appropriate for grades 7-12.
Topozone. This site features digital topographic maps for viewing or printing. A search engine lets you type in a place name and state name from anywhere in the United States. Then you choose from the selections found and view the part of the topographic map shown. Cursor arrows let you navigate between images. A target cursor allows you to zoom in or zom out by changing scales or to determine the specific location of a place of interest in various coordinate systems (degrees and minutes, decimal degrees, UTM). You can print the part of the map shown.
Color Landform Atlas of the United States. John Hopkins University Applied Physics Laboratory. This site lets you select any state in the United states. For each state there are various map options including a shaded color relief map, a shaded color relief map with county boundaries, a black and white shaded relief map, detailed maps of areas within the state, a satellite image, historic maps, and a post-script map. These maps are wonderful tools for illustrating geography or physiography within each state. Landforms and the manner in which landforms change across each state are wonderfully shown in shaded relief. Links are also provided to other web sites to provide more information and facts about the state chosen.
Tapestry of Time and Terrain, U.S. Geological Survey. 2000. A great site for visualizing the connection between bedrock geology and physiography (landscapes) and also for illustrating the distribution of rocks of different ages around the United States. The map on the front page is a combination of a 3-D shaded relief map and a geologic map. The Two Maps option shows each map separately and then merges them together using a Quicktime® plug-in. The Description of Features Option lets you zoom in on selected physiographic regions shown on the map and provides specific information about those regions. The Rock of Ages option shows the legend (explanation) for the geologic map (classified by intervals of geologic time). You can choose a time period to see where rocks of that age are exposed at the surface in the United States. There is a short description of the rocks and fossils from that time period, and a series of options for zooming in on specific regions. The web preview is also available on CD from the USGS for a low cost.