Search results
Results from the WOW.Com Content Network
The Libre Map Project was started by Jared Benedict and around 100 additional individuals contributing money to purchase (or "liberate") a full set of 1:24K scale USGS topographic maps in Digital raster graphic form. [1] The map files were then hosted by archive.org to ensure the map data will continue to be freely available to everyone ...
The USGS also utilizes data from The National Map Corps, which consists of volunteers who devote some of their time to provide cartographic information on structures. [ 4 ] The National Map is the official replacement for the USGS topographic map program .
Today's U.S. Topo quadrangle (1:24,000) maps are mass-produced, using automated and semiautomated processes, with cartographic content supplied from the National GIS Database. [34] In the two years from June 2009 to May 2011, the USGS produced nearly 40,000 maps, more than 80 maps per work day. [34]
The various features shown on the map are represented by conventional signs or symbols. For example, colors can be used to indicate a classification of roads. These signs are usually explained in the margin of the map, or on a separately published characteristic sheet. [17] [18] [19] Topographic maps are also commonly called contour maps or ...
Today, the United States Geological Survey Library's users have access to over 1.7 million items: over 980,000 books and journals, over 600,000 maps, over 8,000 electronic media items (DVDs, CDs), and subscribes to over 113,000 electronic journal titles and eBooks. Materials include USGS publications, as well as those produced by state and ...
The NED dataset is a compilation of data from a variety of existing high-precision datasets such as LiDAR data (see also National LIDAR Dataset - USA), contour maps, USGS DEM collection, SRTM and other sources which were reorganized and combined into a seamless dataset, designed to cover all the United States territory in its continuity.
In most European countries, the largest scale topographic map series is a 1:25.000 scale series. Notable exceptions are Austria (1:50,000) and Finland (1:20,000). Many non-European states limit the largest scale of their map series, usually to 1:50,000 scale, frequently due to the large size of the country covered (and hence for financial reasons).
A graphical or bar scale. A map would also usually give its scale numerically ("1:50,000", for instance, means that one cm on the map represents 50,000cm of real space, which is 500 meters) A bar scale with the nominal scale expressed as "1:600 000", meaning 1 cm on the map corresponds to 600,000 cm=6 km on the ground.