 Digital Raster Graphics (DRGs) are digital copies of standard USGS map
series topographic maps. The Coweeta LTER collection covers the
southern Appalachian region and is available at 1:24,000, 1:100,000, and
1:250,000 scale.
The terms 'DRG', 'digital topographic map', and 'digital raster graphics'
describe the same product: a scanned USGS topographic map.
View
& Download Digital Topographic Maps
|
|
Metadata:
1:24,000 |
1:100,000 |
1:250,000
Guide
to mosaicing DRG's
Mosaicing is the process of stitching adjacent maps together to create a
larger geographic coverage. If you have questions, please contact Coweeta LTER directly for assistance
(706.542.5691).
Locating
maps
Enter COGENT and either navigate to the area of interest or if you know
the name of the quad, type the name into the search box.
File Formats
Files are offered in ERDAS IMAGINE .img format, directly readable in both
ERDAS IMAGINE and ESRI ArcView/ArcMap software. For users requiring other
formats, geotiff format can be made available by contacting Information
Management directly.
Download Times
Coweeta LTER DRG's have been converted to
4-bit data, reducing files sizes dramatically. Downloads are provided in
self-extracting zip files (no additional software is required by you),
and are normally 1-2 Mb per map. Actual download times depend on the
speed of your connection to the internet.
Georeferencing and Projection Information
All Coweeta LTER GIS files are georeferenced and projected to Universal Tranverse Mercator (UTM), Nad27, Zone
17.
Printed Topographic Maps
High quality prints of DRG's can be arranged by contacting Coweeta LTER
Information Management directly: Tel. 706.542.5691. |