The image on this plaque depicts your view of the Konza Prairie and the Kansas River Valley. Looking from west to southwest, the view is typical of the Flint Hills in their natural state. Due west is the floodplain of the Kansas River and to the southwest, along the horizon, are two low rounded hills. The difference in elevation from the grass covered hilltops to the wooded stream valleys is about 400 feet. Given the opportunity to explore the landscape of the image, you would find clues to the underlying geology of the Flint Hills. A hike, along a stream valley or an eroded hillside, would allow you to see layers of exposed sedimentary rocks: limestones (some with chert/flint) and mudrocks. These exposed rocks are between 240 and 290 million years old. Geologists refer to rocks of this age as Permian. Originally described in the 1800s, the name "Permian" is taken from similar rock formations of the southern Ural Mountains located near the town of Perm, Russia.
Careful study of fossils and related features show that the region's sedimentary rocks were formed from sediments deposited on the bottom of an ancient shallow sea. The climate of this ancient marine environment was very dry, much like parts of the Persian Gulf during the twentieth century. Limestone layers (A, B, C, and E) and some thin mudrock layers record these marine conditions. Thicker mudrock layers (D) provide evidence of ancient soils. These ancient soils developed when sea level lowered and exposed the area to terrestrial processes in the present day climate, thick mudrock layers weathered (decompose or disintegrate) easily. The weathering of these layers form the hillsides and valleys of the view you now see. Limestones, with their numerous layers of chert/flint, are more resistant to weathering than the softer mudrock layers. It is the limestone layers which cap the hills or create prominent ledges in the hillsides. The chert/flint, found near the surface, is harder than steel, making it difficult to plow and cultivate the soil. It is this distinctive geologic feature which preserves the native conditions of the region and gives the region its name: THE FLINT HILLS.