KARST FEATURES MAPPING IN NEW JERSEY

The New Jersey Geological and Water Survey (NJGWS) has increased focus on karst features derivative mapping in the northern part of the state. Karst mapping is critical in New Jersey, which includes high population density areas with active development and an industrial history. The resulting karst features maps use field observations, aerial imagery, and remote sensing data to identify and characterize karst features, including sinkholes, springs, caves, and sinking and rising streams, throughout 7.5-minute quadrangles at 1:24,000 scale. The maps also describe regional impacts and topography due to karstification and incorporate past karst and geologic mapping activities and publications into the results. This presentation will showcase results of this karst mapping, as well as discuss methods for achieving these results, including field techniques and GIS software. New GIS tools have contributed positively to karst mapping efforts in New Jersey, especially in areas with limited access due to private property, and this presentation will pay particular attention to specific GIS tools successfully used in the karst features maps. These tools include those for identifying closed depressions from a LiDAR-derived Digital Elevation Model (DEM) and those for using multiband composite raster datasets from a DEM.