Two kinds of GIS databases were compiled. The first of these was a general raster grid that covers most of the study area, T. 16 S. to T. 30 S. and R. 3 E. to R. 21 E. (fig. 2). This grid is based on the township-and-range system divided into quarter-section (1/2 mile by 1/2 mile) cells and covers about 26,000 km2 (10,000 mi2). The second GIS database was a detailed vector database for Allen, Anderson, Coffey, Neosho, Wilson, and Woodson counties, referenced to the UTM coordinate system (fig. 2).
The raster database for Olpe and Olpe-complex soils was created with gravel elevation as the value for each cell. Although this grid system has many shortcomings for accurate cartographic work, it is convenient to use, and for the purpose of this database, small locational anomalies are of little significance. The key attribute for this database is actual elevation of chert gravel, not accurate areal limits. County metric topographic maps (1:100,000) were used for determining the grid and transfering data from soil survey reports. Elevation data for Olpe cells were entered into the database if the Olpe soil covered at least 10 acres (4 hectares) or 1/16th of the quarter section, as estimated from the soil maps. The elevation of the soil was given as the highest elevation contour (nearest 5 m).
The detailed vector database was created for a six-county area in the middle and lower Neosho basin (Byerley, 1995). Geographic data were entered by manual digitizing in vector format from 7.5-minute topographic quadrangle maps. The vector database contains all main rivers and their principal tributaries, reservoirs, county boundaries, and selected cities, as well as geomorphic distribution of alluvial soils and chert gravel. Other kinds of GIS databases were utilized, including various digital elevation models (DEM) and Landsat multispectral scanner (MSS) images from the 1988 growing season (Aber et al., 1997).
Kansas Geological Survey
Web version March 18, 1998
http://www.kgs.ku.edu/Current/1997/aber/aber6.html
email:lbrosius@kgs.ku.edu