PRODUCING DIGITAL SURFICIAL GEOLOGIC MAPS FOR DIVERSE AUDIENCES

A new mapping program at the Kentucky Geological Survey is generating digital maps of nonlithified geologic materials specifically designed for application by technical and non-technical end users. Prospective audiences include seismologists, geophysicists, land-use planners, transportation engineers, groundwater hydrologists, and producers of raw materials such as aggregate and clay. Increasing use of GIS software by these clients allows them to more easily utilize geologic information. Insufficient geological training commonly limits their ability to interpret raw technical data and make geologically sound decisions.

We are using standard geologic mapping techniques and process geomorphology to produce lithologically-based surficial geologic maps along the Ohio River valley in western Kentucky. Map unit characterizations are based upon landform mapping, subsurface lithologic logs, geophysical logs, grain size analyses, outcrop exposures, and soil data. The stratigraphic information collected for the geologic map units is being compiled with available geotechnical data, including shear wave velocities and various parameters of soil mechanics.

The resulting digital geologic maps have attribute tables which include both geologic and geotechnical information in formats which can be used or translated by a variety of end users. These data can be accessed to quickly and easily create various derivative maps related to seismic hazard assessment, municipal land-use planning, transportation planning, construction, and environmental issues. Regional geologic mapping of this type is useful for general planning or modeling purposes, and does not replace site specific studies. This new generation of 3D surficial geologic maps is in addition to the existing statewide set of vectorized, georeferenced, digital, bedrock geologic maps.