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

Get top class preparation for competitive exams right from your home: get questions, notes, tests, video lectures and more- for all subjects of your exam.

Get video tutorial on: Examrace YouTube Channel

Vulcanicity

• 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

Features

• 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

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

Effects of Volcano

Lava – Based on Texture

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

Lava – Based on Composition

The acidic and basic forms of lava are explained here.

Volcano Based on Form

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

Volcano Based on Mechanism

✍ Manishika