geohazards
Natural geological threats
Geohazards are natural phenomena that pose risks to human life, property, or infrastructure.
The term covers earthquakes, volcanic eruptions, landslides, tsunamis, sinkholes, and similar earth-based threats.
Engineers and planners assess geohazards when siting buildings, pipelines, or roads: The coastal region faces multiple geohazards including erosion and subsidence.
Sudden ground movement
- fault linesFractures between rock masses
- tremorsSlight shaking movements
- liquefactionConversion to liquid state
- ground shakingEarth's surface vibrating
aftershocks · seismic waves · tectonic activity · magnitude · epicenter · foreshocks · plate boundaries · seismic risk
Earthquake-generated ocean waves
- storm surgeWind-driven coastal flooding
- coastal erosionLand loss at sea edges
- sea level riseIncreasing ocean surface height
- wave actionMotion of ocean swells
cliff collapse · tidal flooding · beach erosion · overwash · rip currents · cyclone damage
Ground collapse cavities
- groundwater depletionExcessive withdrawal from underground reserves
- mine collapseUnderground excavation failure
- permafrost thawPermanently frozen soil melting
- compactionReducing volume through pressure
Reduction of severity
- early warning systemsMonitors that signal approaching threats
- disaster preparednessPlanning for potential crises
- exposure assessmentEvaluating contamination intake levels
- building codesLaws governing structure safety
emergency response · risk reduction · remote sensing · instrumentation · forecasting
Sudden forceful discharges
- lava flowsMoving volcanic rock
- pyroclastic flowsVolcanic gas-debris surge
- ashfallAirborne volcanic debris descending
- laharsVolcanic debris flows
magma · calderas · volcanic gases · tephra · volcanic bombs · stratovolcanoes · fumaroles · sulfur dioxide
Falling mountain debris
- mudslidesWet earth mass movements
- avalanchesMassive snow collapses
- slumpsFalls or droops suddenly
- rock slidesMass wasting of stone
talus · scarp · steep terrain
earthquakes
Sudden ground movement
- fault linesFractures between rock masses
- tremorsSlight shaking movements
- liquefactionConversion to liquid state
ground shaking · aftershocks · seismic waves · tectonic activity · magnitude · epicenter · foreshocks · plate boundaries · seismic risk · active faults
tsunamis
Earthquake-generated ocean waves
- storm surgeWind-driven coastal flooding
- coastal erosionLand loss at sea edges
- sea level riseIncreasing ocean surface height
wave action · cliff collapse · tidal flooding · beach erosion · overwash · rip currents · cyclone damage
sinkholes
Ground collapse cavities
- groundwater depletionExcessive withdrawal from underground reserves
- mine collapseUnderground excavation failure
- permafrost thawPermanently frozen soil melting
mitigation
Reduction of severity
- early warning systemsMonitors that signal approaching threats
- disaster preparednessPlanning for potential crises
- exposure assessmentEvaluating contamination intake levels
building codes · emergency response · risk reduction · remote sensing · instrumentation · forecasting
eruptions
Sudden forceful discharges
- lava flowsMoving volcanic rock
- pyroclastic flowsVolcanic gas-debris surge
- ashfallAirborne volcanic debris descending
lahars · magma · calderas · volcanic gases · tephra · volcanic bombs · stratovolcanoes · fumaroles · sulfur dioxide · ejecta
rockfalls
Falling mountain debris
- mudslidesWet earth mass movements
- avalanchesMassive snow collapses
- slumpsFalls or droops suddenly
rock slides · talus · scarp · steep terrain
geohazardsweather hazards
Dangerous atmospheric phenomena
space weather · biohazards · storms · hurricanes · tornadoes
geohazardsindustrial hazards
Dangers in manufacturing settings
industrial accidents · pollution · chemical spills · nuclear accidents
hazard, geography, hazardous, geology, hazards, geometric, hazarded, geologist, hazarding