SOIL GEOMORPHOLOGY - THE MidContinent BEYOND THE ROCKIES

Landscapes, both past and present, are everywhere capped with soils. As part of a landscape study, the soil, its properties, and its relationship to the landscape are investigated. Soil geomorphology is the study of the processes of landscape evolution and the influence these processes have on the formation of soils on that landscape. A soil-geomorphic study usually consists of three investigative aspects: a) surficial stratigraphy and parent material b) landscape form and process defined in time and space and c) correlation of soil properties to landscape features. In the MidContinental US, soil geomorphology emerged as an essential component discipline of the geological sciences in the early 1950’s. Researchers began to demonstrate the close interdependence of soils and landscapes and the importance of subsurface investigation of paleosols and paleo-landscapes to Quaternary research. Chief among those responsible for advancing the discipline of soil-geomorphology in the central US was Robert Ruhe. Ruhe influenced the thinking of a generation of scientists including Peter Birkeland. Ruhe’s constant adherence to the soil-geomorphic investigative approach set a precedent for landscape models that today provides the fundamentals for reconstructing geomorphic and Quaternary history throughout the MidContinent and generally, the USA. A few studies from the MidContinent that reflect this approach and have led to the establishment of regional Quaternary stratigraphic frameworks will be presented.