Geological Survey Program
Geothermal Investigations in Missouri
Geothermal energy is a renewable resource that is underutilized. The State Geothermal Data project, organized by the Association of American State Geologists with funding from the United States Department of Energy, will bring data from all 50 states into the National Geothermal Data System (NGDS), in order to identify and characterize geothermal energy resources across the nation. The purpose of this site is to present data collected for this project as well as other geothermal investigations in Missouri.
Understanding the earth beneath our feet is the first step in understanding the world around us. Geologic maps are the most fundamental source of geologic information for the earth sciences. Geology affects everything from ecology to highway construction. Bedrock maps contribute to our knowledge of the likelihood of damage from earthquakes, landslides or sinkhole collapse and they are used for exploration and development of mineral, fuel and groundwater resources. Click on the map above to use the interactive geologic map of Missouri. Here you can explore the bedrock geology of the state. Use the map to zoom in to your home area and print a geologic map. Keep in mind that not all of the state has been mapped geologically in great detail. For much of the state, geologic map data will only be displayed up to a scale of 1:500,000.
Shapefiles created by staff were used to make the interactive map can be downloaded from the Missouri Spatial Data Information Service (MSDIS). Other geologic maps for Missouri are available from our Missouri Geology Store and may be located using the online geologic map index. The maps used to create the interactive geologic map of Missouri were those made since the Geological Survey Program began using a Geographic Information System. In the Future, older maps will be incorporates as well as new maps produced for ongoing projects.
Over a three year period the following maps and datasets will be produced to provide information about Missouri’s geothermal resources as well as information needed to develop it. Links to the data will be provided as it becomes available.
- Heat pump log dataset (indicates the current distribution of heat pump systems in Missouri and provides lithologic information) Excel File -- August 2011
- Geologic map (see above)
- Bottom hole temperature (derived from oil and gas well logs, the information will be used to create an updated aquifer temperature map) Excel File -- August 2011
- Depth to bedrock map (provides information critical to heat pump installation)
- Whole rock chemistry dataset (provides information for determining rock unit suitability for various construction and industrial purposes)
- Borehole lithology log dataset (lithologic descriptions of well cutting from water, oil and mineral test wells located throughout the state)
- Aquifer temperature map (last updated in 1981, aquifer temperature map may be used to indicate new geothermal resources)
- Trace constituent chemistry dataset (water quality reports from public water supply districts)
Geothermal Use in Missouri
Geothermal energy is generally thought of as reservoirs of hot water that exist at varying temperatures and depths below the Earth's surface. Deep wells can be drilled into underground reservoirs to tap steam and hot water that can be brought to the surface for use in a variety of applications, including electricity generation, direct use, and heating and cooling. In the United States, most geothermal reservoirs are located in the western states, however, people across the nation can take advantage of the relatively constant temperatures of the earth to heat and cool their homes with ground source heat pumps.
Though the state of Missouri does not have hot springs, fumeroles or any of the geothermal features found in some western states, Missourians use the moderating influence the earth to heat their homes in winter and cool them in summer. This is done through the use of ground source heat pumps. The Missouri Department of Natural Resources, Geological Survey Program regulates the construction of some types of heat pump systems and provides information online.
There are three basic types of ground source heat pump systems – closed loop vertical, closed loop horizontal and open loop. Geological considerations will play a role in determining what type of system is best. Other considerations, such as lot size, also play a role.
- Open loop systems use groundwater as the heat exchange fluid. The well is usually also used as a drinking water supply. Quality of groundwater for this type of system must be a consideration. The Missouri Department of Natural Resources, Water Resources Center provides information about groundwater provinces in Missouri.
- Closed loop horizontal systems require the installation of pipe filled with approved heat exchange fluid in trenches. Construction of trenches depends on type and thickness of unconsolidated earth material. The Geological Survey Program has applicable data in the form of surficial materials maps and thickness maps. The lithology log dataset, part of the State Geothermal Data Project, will be available for download soon.
- Closed loop vertical systems require the installation of pipe filled with approved heat exchange fluid in a vertical borehole. In most cases this borehole will be drilled into bedrock.