Geological Survey (USGS) produces geospatial databases and topographic maps
for the United States of America.
SII is now seen as the authoritative source of not only framework data sets but also standard topographic map
symbolization and specifications for statewide topographic mapping.
Genuine USGS topographic maps
- 1:24,000 and 1:100,000 scales
This requires a surveyor's judgement to produce a good topographic map
The US Topo program began in November 2008 as the USGS embarked on a program to create an updated series of topographic maps
derived from The National Map databases.
This product depicts the standard topographic map
features such as roads, contours, rivers, lakes, built-up areas, towers, spot heights, etc.
High-resolution digital ortho-rectified imagery that provides some of the feature information content now symbolized on topographic maps
(see Figure 1).
Zone information is listed in the lower left-hand corner of your topographic map
Farsi GeoTech's addition to the World Topographic Map
consists of detailed feature and point of interest layers such as administrative boundaries, facilities (including parks and airports), railroads, and parcels.
This paper discusses the transition from analog to digital maps and the concept of the National Digital Cartographic Database (NDCDB); separating the topographic map
into individual theme-based data layers and their importance to the National Spatial Data Infrastructure (NSDI); the recombination of these data layers into a spatial data framework, with enhanced local data, monitoring, statistical descriptions, scientific assessments, analyses, and application capabilities to form The National Map (TNM).
5-minute series topographic map
and Tom Harrison Cartography's ``Trail Map of the Mammoth High Country.
The mathematical term "level set" refers to a contour, much like the curve linking points of equal elevation on a topographic map