Sinkholes, caves, and springs: Karst development in central Butler County, Kansas.

Abstract

Research was conducted to study the geology and hydrology of sinkholes, springs, and caves formed in Lower Permian, Fort Riley Limestone, located in central Butler County, Kansas. This research project was undertaken to better understand the controlling factors of these karst features and the processes that produce them in a portion of Kansas that is undergoing rapid population growth and increased groundwater usage. Research was conducted in seven phases: literature search, locating karst features, measuring bedrock fracture joint trends, surveying and mapping the major caves, determining an estimated discharge of the spring Cave resurgence, dye tracing, and water chemistry analysis. Recognizable karst landforms within the defined study area were plotted onto a base map to demonstrate their geographic, geologic, and hydrologic relationships. Karst features identified were 125 sinkholes, a major cave system composed of at least three enterable segments (spring Cave, Smith Cave, and Windmill Cave), and one large spring. The karst terrain found within the study area is clearly a system of interrelated features and processes. Long-term solution of the bedrock allows karst features to form, joints and bedding planes to enlarge, and creates an efficient network of subsurface drainage. Factors controlling karst development in the study area are lithology, thickness, and dip of the bedrock; presence of well-defined fracture joints and bedding planes; relatively level topography; nearby entrenched river valleys; lack of thick surficial cover; and climate. Of these influences, solution's activity at joints plays a major role in the formation of sinkholes and cave passages; however, a complex combination of all the controlling factors is responsible for the present, unique, and dynamic karst system consisting of sinkholes, caves, and springs.