THE DEVELOPMENT OF A KARST FEATURE DATABASE FOR SOUTHEASTERN MINNESOTA

A karst feature database of southeastern Minnesota has been developed that allows sinkhole and other karst feature distributions to be displayed and analyzed across existing county boundaries in a geographic information system (GIS) environment. The central Database Management System (DBMS) is a relational GIS-based system interacting with three modules: GIS, statistical, and hydrogeologic modules. Data tables are stored in a Microsoft Access 2000 DBMS and linked to corresponding ArcView shape files. The current Karst Feature Database of Southeastern Minnesota was put on a Windows NT server accessible to researchers and planners through networked interfaces. Initial spatial analyses and visualizations of karst feature distributions in Southeastern Minnesota were conducted using data extracted from the karst feature database. A series of nearest-neighbor analyses indicates that sinkholes in southeastern Minnesota are not evenly distributed (i.e., they tend to be clustered). ArcInfo, ArcView and IRIS ExplorerTM were used to generate a series of 2D and 3D maps depicting karst feature distributions in southeastern Minnesota using data exported from the GIS-based karst feature database. The resulting maps allow regional trends to be visualized and extend county-scale trends to larger state-wide scales.