This portal provides information on how we use water on an everyday basis. Users can choose from some general water-use topics on the left side of the graphic, or from the categories of water use on the right side. A text menu of the topics is provided below the graphic. Topics include groundwater, surface water, domestic versus commercial consumption, irrigation and livestock, and industrial uses. ... Full description.

This report discusses how natural processes and human activities affect the interactions of ground water and surface water, and the importance of considering ground water and surface water as a single resource. Topics include natural processes of ground- and surface-water interaction; chemical interactions; and the effect of landscapes on these interactions. There is also discussion of the effects ... Full description.

This site offers the online version of a book published by the United States Geological Survey (USGS). It is intended to provide a brief introduction to the concept of plate tectonics, highlighting some of the people and discoveries that advanced the development of the theory. It is the companion volume to the map, 'This Dynamic Planet', which shows the locations of major volcanic belts, fault systems, ... Full description.

This map generator takes longitude/latitude pairs as input and plots them on a Mercator projection map along with land/sea and political boundaries. The map bounds will be about 10 percent larger than the bounds of the entered data points. As an example, the generator is loaded with default values that yield a map of Cape Cod, Massachusetts, generated by supplying the longitude and latitude values ... Full description.

To commemorate the 200th anniversary of the Lewis and Clark Expedition and the 125th anniversary of the United States Geological Survey (USGS), the USGS National Center for Earth Resources Observation and Science (EROS) has assembled a collection of satellite images that provides a contemporary view of the route that Lewis and Clark took from St. Louis, Missouri, to the Pacific Coast. The twenty-two ... Full description.

This collection of 3D (anaglyphic) images is derived from photography that Major John Wesley Powell commissioned to document his Second Expedition (1871-1872) and later expeditions on the Colorado Plateau. Now-famous localities such as the Green River, Flaming Gorge, Dinosaur National Monument, Glen Canyon, and the Grand Canyon are documented. The images were created by modifying the original stereo ... Full description.

This United States Geological Survey (USGS) fact sheet provides information on USGS professional papers, bulletins, and circulars that deal with map projections. The information includes descriptions of common projections, additions of new projections, a bibliography, software for generating projections, and others. There is also a poster that summarizes basic information on map projections. Some ... Full description.

This interactive viewer provides access to satellite imagery for virtually any point on the Earth. Users can select a satellite and sensor and either type in latitude and longitude or click on a point on the index map. The viewer will show a mosaic of the most recent cloud-free satellite browse images around the point selected. It will appear in a new window along with some metadata, including path, ... Full description.

This poster features a portrait of Gerardus Mercator on one side and examples of the eighteen most common map projections on the other. Each example includes a description that explains the properties and uses of the projection. There are also summary tables of projection properties, general uses, and geographic areas most suitable for mapping with a given projection. The poster is viewable online ... Full description.

This article, published in the National Atlas, explains what latitude and longitude are and how they are used to define a location on Earth. It discusses Earth as a sphere and points out that latitude values are counted from the equator (0 degrees) to the poles (90 degrees) and that longitude lines divide the Earth equally into 360 degrees from east to west. Other topics include subdivision of degrees ... Full description.