Iowa Caves and Karst

Iowa landforms have been shaped by a range of processes, including multiple glacial incursions. Many of these diverse landforms harbor a variety of karst features, including numerous examples of caves formed by both solutional and mechanical processes acting on an array of dolostones, limestones, gypsum, and sandstones. Cave development has been noted in several geologic systems, ranging from upper Cambrian to Pennsylvanian sandstones and lower Silurian to middle Mississippian carbonates. Distributional patterns of cave and karst development in Iowa are examined as a function of distinct physiographic regions, respective lithologies, hydrogeologic settings, and structural morphologies illustrated by representative sites. Karst systems have played a significant role in shaping Iowa’s unique surficial and subterranean habitats as well as archaeological, historical, and modern landscape uses. Ongoing exploration and study of Iowa caves continues to improve our collective understanding of past climate patterns and modern water quality issues as well as supporting comparative models of karst development on a regional scale. This chapter provides an overview examining principal karst-associated landscapes and controls associated with paleokarst, pseudokarst, and karst cave occurrences in Iowa.