GeoMiner Free earth-science tools

Built by a geologist

Permafrost identification and geology

Ground soil or rock that remains at or below 0°C continuously for at least two consecutive years, regardless of whether water is present. Permafrost underlies approximately 25% of the Northern Hemisphere's land surface and can extend to depths of over 1,500 m in Siberia. The active layer above the permafrost thaws seasonally, and its behavior has major implications for infrastructure, slope stability, and greenhouse gas release. Field: glacial geology. Example: Buildings in Dawson City, Yukon, must be built on pilings to prevent heat transfer into the underlying permafrost, which would cause melting, ground subsidence, and structural damage.. Related terms: Active layer, Thermokarst, Periglacial, Ground ice.

  • Browse all geology and mining glossary terms — Compare this entry with the complete GeoMiner glossary collection.
  • Previous: Peridotite — A coarse-grained ultramafic intrusive igneous rock composed primarily of olivine 40% with subordinate pyroxene and minor amounts of garnet, spinel, or…
  • Next: Phenocryst — A relatively large, conspicuous crystal embedded in a finer-grained groundmass in a porphyritic igneous rock.

Sources, scope & corrections

These authoritative resources support category-level nomenclature, terminology, identification methods, and safety. When a specimen-specific safety warning appears, the public-health source listed here directly supports that precaution. They are not line-by-line citations for every other property on this entry, and natural specimens vary.

Editorial owner
GeoMiner
Last updated
2026-03-30T15:19:42.055955+00:00
Review status
Published; not independently peer-reviewed
  • USGS Thesaurus — U.S. Geological Survey. Controlled earth-science terminology used to describe USGS information resources.
  • Glossary of Geologic Terms — U.S. National Park Service. Geologic definitions prepared by the NPS Geologic Resources Inventory.

Read GeoMiner's editorial methodology or report a content issue.

Common questions

What does Permafrost mean in geology?
Ground soil or rock that remains at or below 0°C continuously for at least two consecutive years, regardless of whether water is present. Permafrost underlies approximately 25% of the Northern Hemisphere's land surface and can extend to depths of over 1,500 m in Siberia. The active layer above the permafrost thaws seasonally, and its behavior has major implications for infrastructure, slope stability, and greenhouse gas release.
What is an example of Permafrost?
Buildings in Dawson City, Yukon, must be built on pilings to prevent heat transfer into the underlying permafrost, which would cause melting, ground subsidence, and structural damage.
Which earth-science field uses the term Permafrost?
Permafrost is used in glacial geology.
Which terms are related to Permafrost?
Related terms in this reference are Active layer, Thermokarst, Periglacial, Ground ice.

JavaScript is loading the interactive GeoMiner experience. The identification tools provide educational candidates, not laboratory confirmation.