4.2.5

Volcanic Hazards

Test yourself

Volcanic Hazards And Their Impacts

Volcanic hazards include lava flows, ash falls, lahars, pyroclastic flows, tephra, volcanic rocks, and toxic gases. Their impacts depend on speed, size, frequency, and spread.

Illustrative background for Lava flows and ash fallsIllustrative background for Lava flows and ash falls ?? "content

Lava flows and ash falls

  • Lava flows are streams of molten rock from volcanoes, destroying everything in their path.
  • Ash falls are fine volcanic particles that drift through the air and settle, causing roof collapse and health problems.
    • Lava and ash can also create fertile soils, benefiting farming in the long term.
Illustrative background for Lahars and pyroclastic flows Illustrative background for Lahars and pyroclastic flows  ?? "content

Lahars and pyroclastic flows

  • Lahars are volcanic mudflows formed when ash mixes with water, flowing rapidly and burying areas.
  • Pyroclastic flows are fast-moving currents of hot gas and volcanic matter that devastate large areas.
    • Lahars and pyroclastic flows can reshape landscapes, creating new landforms and attracting tourism.
Illustrative background for Toxic gases from volcanoesIllustrative background for Toxic gases from volcanoes ?? "content

Toxic gases from volcanoes

  • Volcanoes emit gases.
    • like sulfur dioxide, carbon dioxide, and hydrogen sulphide, posing serious health risks
  • Toxic gases can spread over large areas quickly.
    • causing respiratory problems and acid rain
  • Some gas emissions help scientists monitor volcanic activity and predict future eruptions.
Illustrative background for Speed, size, frequency, and spread Illustrative background for Speed, size, frequency, and spread  ?? "content

Speed, size, frequency, and spread

  • Speed affects how quickly volcanic hazards impact populated areas.
    • influencing damage and casualties
  • Size determines the volume of material or gas released.
    • affecting hazard scale
  • Frequency indicates how often eruptions occur.
    • influencing risk level over time
  • Spread shows how widely hazards affect regions.
    • shaping emergency response and recovery

Jump to other topics

1Paper 1 - Changing River Environnments

2Paper 1 - Changing Coastal Environments

3Paper 1 - Changing Ecosystems

4Paper 1 - Tectonic Hazards

5Paper 1 - Climate Change

6Paper 2 - Changing Populations

7Paper 2 - Changing Towns & Cities

8Paper 2 - Development

9Paper 2 - Changing Economies

10Paper 2 - Resource Provision

Unlock your full potential with Seneca Premium

  • Unlimited access to 10,000+ open-ended exam questions

  • Mini-mock exams based on your study history

  • Unlock 800+ premium courses & e-books

Get started with Seneca Premium