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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:
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