US TOPO PRODUCT STANDARD
This document defines a U.S. Geological Survey (USGS) digital topographic map. This map series, named “US Topo,” is modeled on what is referred to as the standard USGS 7.5-minute (1:24,000-scale) topographic map series that was created during the period from 1947 to approximately 1992. The US Topo map product has the same extent, scale, and general layout as the older standard topographic maps. However, unlike the previous maps, US Topo maps are published using Adobe Systems Inc. Portable Document Format (PDF) with a geospatial extension that is called Georeferenced PDF (GeoPDF), patented by TerraGo Technologies. In addition, the US Topo map products incorporate an orthorectified image along with data that was included in the standard 7.5-minute topographic maps. US Topo maps are intended to serve conventional map users by providing Geographic Information System (GIS) information in symbolized form in the customary topographic map layout. The maps are not intended for GIS analysis applications.
A full-size style sheet template in PDF that defines the placement of map elements, marginalia, and font sizes and styles accompanies this standard. The GeoPDF US Topo maps are fashioned to conform to this style sheet so that a user can print out a map at the 1:24,000-scale using the dimensions of the traditional standard 7.5-minute quadrangle. Symbology and type specifications for feature content are published separately. In addition, the GeoPDF design allows for custom printing, so that a user may zoom in and out, turn layers on and off, and view or print any combination of layers or any map portion at any desired scale.