National Land Imaging (NLI) was an interagency effort (begun in 2006) to develop a long-term plan to achieve technical, financial, and managerial stability for operational land imaging. In August 2007, the working group released the recommended plan in a...
The water cycle, also known as the hydrologic cycle, describes the continuous movement of water on, above, and below the surface of the Earth. For a summary go to water cycle.Learn more: Georgia Water Science Center 
The Gap Analysis Program (GAP) is a state-based cooperative effort to map major indicators of biodiversity over states, along with the existing network of conservation lands. The indicators of biodiversity that the GAP state projects map using geographic...
This massive database updates our knowledge of the Nation’s land cover and documents precisely where land cover change has occurred between 2001 and 2006. NLCD is used for thousands of applications in such diverse investigations as ecosystem status and...
Landsat image data processing takes 1 to 5 days. Once a request is submitted and the data is processed, an email notification containing the direct download URL is sent.After Landsat scenes are processed, they are also made available for immediate...
The USGS provides access to water-resources data collected at approximately 1.5 million sites in all 50 States, the District of Columbia, and Puerto Rico. Online access to this data is organized around the categories listed to the left.The USGS...
A rock is an aggregate of one or more minerals; or a body of undifferentiated mineral matter. 
Forest Visitor Maps are best used to view an entire National Forest. They are great for driving through or planning a trip to the forest, showing recreational sites, campgrounds, public information sites and other attractions in the forest.Wilderness...
Gas hydrates are found in sub-oceanic sediments in the polar regions (shallow water) and in continental slope sediments (deep water), where pressure and temperature conditions combine to make it stable. Learn more: Gas Hydrates 
The U.S. Food and Drug Administration and States regulate bottled water. For general information about bottled water, some sources are the International Bottled Water Association and NSF International.