MAPPING COLORADO'S GEOLOGY AND GROUNDWATER RESOURCES ON A COUNTY-WIDE SCALE

GIS provides a useful tool for displaying Colorado’s geology and groundwater resources on a county-wide scale. The Colorado Geological Survey (CGS) has thus far completed three counties (Douglas County, Park County, and Chaffee County) with more counties planned for the future. These studies compile the most recent geologic mapping and interpretations focusing on groundwater occurrences in the various geologic formations found in the area. Map projects emulate 3-D models with layers representing each hydrogeologic unit. Each unit is mapped by outcrop, subsurface extent, and connections with surface water through alluvial systems.

The results have been developed into web-based geologic maps with downloadable geodatabases. The web-based maps allow the viewer to alternate between layers to understand the 3-D characteristics of the regions. The geodatabases contain feature datasets of the geologic units, thickness contours, faults, and water wells attributed to the geologic units.

These studies represent a unique combination of the latest detailed geologic mapping and GIS techniques to assess geology and hydrogeology on a regional scale. These data are useful in planning future development.