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Volcanoes: A Year of Earth's Fiery Spectacle

Key Facts

• Volcanoes, shaped by lava and ash eruptions, typically form cone-shaped mountains or hills.
• Magma, upon reaching the surface, transforms into lava, solidifying into rock upon cooling.
• Volcanic eruptions commonly occur at destructive and constructive plate boundaries, not at conservative boundaries.
• Some volcanoes emerge beneath water, along seabeds or ocean floors.

Different Stages of Volcanoes

• Active Volcanoes: Likely to erupt or currently erupting.
• Dormant Volcanoes: Not expected to erupt soon.
• Extinct Volcanoes: No anticipated future eruptions.

Reasons for Volcano Formation
Volcanoes originate from magma formation in the Earth's lower crust, driven by the movement of tectonic plates. Plate movement-induced friction leads to earthquakes and volcanic eruptions, creating new pathways for magma to reach the Earth's surface as lava.

Types of Volcanoes

1. Shield Volcanoes:

   • Largest active volcanoes, primarily composed of basalt.
   • Low explosivity, unless water enters the vent.

2. Composite Volcanoes:

   • Formed by cooler and more viscous lavas than basalt, leading to explosive eruptions.
   • Accumulation of pyroclastic material and ashes around vent openings.

3. Caldera:

   • Highly explosive, prone to collapse upon eruption, forming depressions known as calderas.

4. Flood Basalt Provinces:

   • Volcanoes emitting fluid lava covering extensive distances.

5. Mid-Ocean Ridge Volcanoes:

   • Erupt in oceanic areas, particularly along the extensive mid-ocean ridge system.

Major Volcanoes in India

Conclusion