Vulcanicity, Volcanoes-Types and 5 Basis for Classification YouTube Lecture Handouts

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Vulcanicity, Volcanoes - Types and 5 Basis for Classification


  • It is the process through which gases and molten rock are either extruded on the earth՚s surface or intruded into the earth՚s crust.
  • Refers to the ways by which magma is imposed into the earth՚s crust
  • Types of Volcanoes:
    • Active
    • Dormant
    • Extinct

Causes of Volcanic Activities

  • Increased quantity of magma in the mantle.
  • Presence of fissure and cracks allowing magma.
  • Increase in the temperature of magma.

Structure of Volcano

Structure of Volcano


  • Lopoliths these are saucer - shaped features
  • Sill, a horizontal sheet of rock
  • Dyke, this is sheet of rock
  • Batholith, is large body of intrusive igneous rock
  • Laccolith, this is a sheet intrusion
  • Phacolith, this is lens shaped pluton
Features of Volcano

Benefits of Volcano

  • Soil Enrichment
  • Volcanic Land Formations
  • Volcanic Minerals and Stones
  • Global Cooling
  • Hot Springs and Geothermal Energy
  • Outgassing and Atmospheric Formation

Distribution of Volcano

Volcanoes are distributed mainly along the Pacific Ring of Fire in Pacific Ocean

Distribution of Volcano

Effects of Volcano

Lava – Based on Texture

Lava is based on texture life Aa, pahahoe and so on.

Lava - Based on Texture

Lava – Based on Composition

The acidic and basic forms of lava are explained here.

Lava - Based on Composition

Volcano Based on Form

Based on form volcanoes are: fissure, shield, dome, ash-cinder, composite and caldera volcano

Volcano Based on Mechanism

Volcano Based on Mechanism


Frequently Asked Questions (FAQs)