U.S. Geological Survey (USGS)
USGS Mission
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The
The mission is accomplished through data collection, research, comprehensive studies, and information services in the broad disciplines of hydrology, geology, biology, geography, and cartography. The National Mapping Program of the USGS provides geographic and cartographic data, information, and related research to meet the broad requirements of the resource managers and Earth scientists in solving national challenges such as disaster response and mitigation, land and resource development, pollution abatement, transportation planning, urban development, and recreational use. |
USGS Maps and Data
The USGS continues to provide the leadership to develop and maintain
the national standard for map production. The 
Western Geographic
Science Center (WGSC) located in Menlo Park, CA is part of the
National Mapping Discipline within the USGS. The WGSC strives to:
- Provide Earth science data and maps.
- Make data accessible to worldwide users.
- Help the public understand and use our data.
The USGS is making available a number of its digital geographic data products to aid in the study, management, and enjoyment of the Lake Tahoe Basin.
- Bathymetry -- A map of underwater terrain.
- Digital Elevation Model (DEM) - Digital records of terrain elevations for ground positions at 10- and 30-m intervals.
- Digital Orthophoto Quadrangle (DOQ) - A photographic map created from aerial photos corrected for distortion.
- Digital Line Graph (DLG) - Vector GIS layers extracted from USGS 7.5-minute topographic quadrangles. DLGs can contain a wide variety of information: hydrography, boundaries, roads, utility lines, etc.
- Digital Raster Graphic (DRG) - Scanned USGS 7.5-minute topographic quadrangles.
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Welcome Digital Data General |
