A Digital Elevation Model (DEM) is a digital data file containing an array of elevation information over a portion of the earth's surface. This array is developed using information extracted from digitized elevation contours from Primary Base Series (PBS) maps. FSTopo or PBS are 1:24,000 scale topographic maps. This dataset is a digital elevation model grid at a resolution of 10 meters by 10 meters. The data was originated from 1:24,000 scale topographic maps (primarily contours). The base data is in the form of an esri lattice file. Derived datasets include generated contours at 10, 25, and 50 meter intervals, degree slope, aspects, and a hillshade for topographic visualization.
George W. Lienkaemper, Theresa J. Valentine
DEMs (Digital Elevation Model data) are used to support a wide range of geographic information system (GIS) applications, including: surface hydrologic modeling, slope and aspect determination, viewshed analysis, fire modeling, contouring, transportation route planning, and profile generation. DEMs are also used to rectify aerial photography in the production of Digital Orthophoto Quads (DOQs). The hillshade is used for visualization of topographic and geological features.