DIGITAL DEPTH TO BEDROCK MAP OF MISSOURI
Development of a depth to bedrock map for Missouri involved production of digital data in various formats as part of creation of the final published map. Geologically appropriate data from Missouri Department of Natural Resources, Geological Survey Program’s digital files for certified water wells and water well strip logs were evaluated for accuracy, spatial distribution and data variation. The depth to bedrock map was based on the first bedrock unit noted in well records that contained surficial material information, creating the first digital data set. A raster interpretation was generated from the depth data using ArcMapTM 10, ESRI Spatial Analyst Extension, and acted as the second digital data set. Contours were generated from the raster data set at 10-foot intervals, forming the third digital data set. The final digital data set created was the data for the final published open file map. Availability of these four digital data sets increases usability of the data for users with varying needs. Preservation of the files related to each stage allowed data to be used for other projects, such as liquefaction hazards maps, without requiring arduous reinterpretation of the original data.