| USGS Digital Raster Graphic Description: USGS Digital Raster Graphic (DRG) format a scanned digital image, with minimum resolutions of 250 dpi up to 1000 dpi high-resolution
scanners, of a U.S. Geological Survey (USGS) topographic map georeferenced to the earth surface and fit to the Universal Transverse Mercator (UTM) projection. The average topographic digital image dataset size for a 7.5-minute digital raster graphic, supported by our 3D GIS mapping software Global Mapper, averages around 8 megabytes in Tagged Image File Format (TIFF 6.0) or an accompanying TIFF world file (TFW) according to the GeoTIFF standard, version 1.0. Digital Raster Graphic of USGS quadrangle topographic map series have been made for the the United States and its territories include: - 7.5-minute maps of United States, Hawaii, and Alaska (limited areas) 1:24,000 and 1:25,000 scale.
- 7.5 x 15-minute maps (limited areas) United States at 1:25,000 scale.
- Pacific Island maps at 1:20,000, 1:24,000, and 1:25,000 scales.
- Puerto Rico and the Virgin Islands at 1:20,000 scale.
- Culebra, its adjacent islands, and the Island of Vieques at 1:30,000 scale.
- Alaska at 1:63,360 scale.
- 30 x 60-minute maps of the conterminous United States at 1:100,000 scale.
- 1 x 2-degree maps of the United States at 1:250,000 scale.
USGS Digital Raster Graphic may be purchased on CD from USGS sales offices or organizations that have partnered with the USGS for distribution of USGS DRG topographic maps. We have provided DRG, TIFF and GeoTiff home page links for more information. Supported Web Pages and Sites: |
