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Geologic Monitoring

Geothermal Systems

Geothermal monitoring at Yellowstone National Park, Wyoming
Geothermal monitoring at Yellowstone National Park, Wyoming. (Click photo to enlarge)

What is a geothermal system?

Geothermal refers to any system that transfers heat from within the Earth to its surface. When the transfer of heat involves water, hydrothermal features representing the geothermal system may form on the Earth's surface. Examples of hydrothermal features include:

Why does the National Park Service monitor geothermal systems?

Development of geothermal energy has historically been found to have an adverse impact on geothermal features, particularly surface features such as geysers, hotsprings, and fumaroles. Care must be taken to prevent irreversible damage to these natural features, which are often culturally significant as well as being important tourist attractions.

Identifying the locations of hydrothermal features and monitoring their heat, water flow, and chemistry can provide land managers with data needed to make informed decisions about management options.

  • Monitoring Book
  • Resource Facts
  • Case Study

Geological Monitoring Book

Vital Signs Monitored

  1. Thermal feature location
  2. Thermal feature extent
  3. Temperature and heat flow
  4. Thermal water discharge
  5. Fluid chemistry

Chapter 5
Geothermal Systems and Monitoring Hydrothermal Features (PDF - 1.96MB)

The potential for geothermal systems exists over broad regions of the United States. Although most of the geothermal systems occur in the western United States, isolated geothermal features are also found in the eastern United States.

This chapter describes vital signs and contains options for monitoring surface and near-surface geothermal features, such as hot springs, geysers, mud pots, and fumaroles. Its focus is the description of techniques for detecting change in hydrothermal systems through time due to natural or human-related causes.

NPS Geothermal Resource Facts

52 parks contain geothermal systems

Yellowstone National Park is home to more than 10,000 thermal features, over 500 of which are geysers.

The Geothermal Steam Act of 1970 requires the NPS to establish and maintain a monitoring program for all units of the National Park System in which thermal features qualify as significant according to the provisions of the act. Currently, sixteen units of the National Park System are listed by Congress as containing significant geothermal features.

  1. Aniakchak National Monument and Preserve
  2. Bering Land Bridge National Preserve
  3. Big Bend National Park
  4. Crater Lake National Park
  5. Gates of the Arctic National Park and Preserve
  6. Haleakala National Park
  7. Hawaii Volcanoes National Park
  8. Hot Springs National Park
  9. John D. Rockefeller Jr Memorial Parkway
  10. Katmai National Park
  11. Lake Clark National Park and Preserve
  12. Lake Mead National Recreation Area
  13. Lassen Volcanic National Park
  14. Mount Rainier National Park
  15. Wrangell-St. Elias National Park and Preserve
  16. Yellowstone National Park

Monitoring Geothermal Systems in the National Park Service

Case study coming soon...

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Last Updated: January 03, 2017