Digital Elevation Model Surficial Maps of Matthiessen and
Starved Rock State Parks in Illinois

The Illinois State Geological Survey (ISGS) will be celebrating its 100th anniversary in 2005. As part of the yearlong centennial celebration, a new series of publications focusing on the geology of selected Illinois state parks will be released. Many Illinois state parks have interesting or unique geologic features. In some cases, the parks exist because of the unique local geology. One of the products associated with the publications is a park map that shows the geologic aspect associated with the park. In the case of the Starved Rock and Matthiessen State parks, the deeply eroded canyons are the unique geologic features. One way to show these canyons on the new park maps was with a color-shaded relief map. Unfortunately, only 30-meter resolution digital elevation models (DEMs) were available, and these did not adequately illustrate the nature of the canyons. Therefore, a high-resolution DEM was required.

Through an internship program with the University of Illinois Department of Geography and ISGS, a geography student was hired to digitize contour lines from 1:24,000-scale topographic maps as well as park features such as scale roads and trails. The student created a five-meter DEM using the TOPOGRID function in ArcInfo. The intern assembled the resulting maps.