Description: These data represent digital GIS sinkhole coverage for all of Kentucky. The highest elevation, closed, topographic contour of each mapped sinkhole was digitized as a GIS polygon. The second highest elevation contour was also digitized where very large, shallow, karst valleys were so expansive that the area covered by the polygon obscured patterns in sinkhole distribution. These karst valleys are mostly confined to the Western Pennyroyal. The spacing of contour intervals on the topographic maps of the state vary in from 40 foot to 10 foot. No attempt was made to use a constant elevation, standardize the outline to a uniform contour interval, or record the elevation of the digitized contour. Digitization was done onscreen using digital raster graphic files of the 7 ½ minute
topographic contours, registered and projected to the Kentucky State Plane coordinate system.