Call Us Now

+91 9606900005 / 04

For Enquiry

253 viewsAll GS PapersGS Paper 2
on 0 Answers


  • A volcano is a crack in the crust of a planet, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber beneath the surface. Volcanism is a process that has been occurring on Earth since the early stages of its evolution over 4 billion years ago.
  • After 38 years, the world’s largest active volcano, Mauna Loa, erupted, spewing ash and debris.


A volcanic eruption’s process

  • The deeper one goes beneath the Earth’s surface, the hotter it becomes.
  • A geothermal gradient is the amount by which the temperature of the Earth increases with depth.
  • A geothermal gradient is the flow of heat from the Earth’s warm interior to its surface.
  • At a certain depth, this heat begins to melt the rocks, resulting in what geologists refer to as’magma.’
  • Because magma is lighter than solid rock, it rises and collects in magma chambers.
  • These magma chambers, which are found at a relatively shallow depth of 6-10 km below the surface, have the potential to cause volcanic eruptions.
  • As magma accumulates in these chambers, it forces its way up through cracks and fissures in the Earth’s crust, causing volcanic eruption.
  • Lava refers to the magma that surfaces on the Earth’s crust; this lava can be explosive at times.
  • Chambers with the potential to cause volcanic eruptions are found at a relatively shallow depth of six to ten kilometres below the surface.
  • As magma accumulates in these chambers, it pushes its way through cracks and fissures in the Earth’s crust. This is referred to as a volcanic eruption. Lava is the name given to magma that rises to the surface of the Earth’s crust.

Hawaiian volcanoes are distinct from other volcanoes.

  • The majority of the world’s volcanoes form along the boundaries of Earth’s tectonic plates, which are massive expanses of our planet’s lithosphere that constantly shift and collide.
  • When two tectonic plates collide, one often sinks deep beneath the other, creating a subduction zone.
  • Temperatures and pressures rise as the descending landmass sinks deeper into the Earth, releasing water from the rocks.
  • The water slightly lowers the melting point of the overlying rock, resulting in magma that can rise to the surface—the spark of life that can reawaken a dormant volcano.
  • Not all volcanoes are caused by subduction. Another type of volcano formation is known as hotspot volcanism.
  • In this case, a hotspot of magmatic activity in the middle of a tectonic plate can push up through the crust and form a volcano.
  • Although the hotspot itself is thought to be mostly stationary, the tectonic plates continue their slow march to the surface, forming a line of volcanoes or islands. This mechanism is thought to be the driving force behind the Hawaiian volcanic chain.

Reasons for the explosive nature of some eruptions

  • Runny magma produces less explosive volcanic eruptions, which are typically less dangerous.
  • Because the magma is runny, gases can escape, resulting in a steady but relatively gentle flow of lava from the volcano’s mouth. This is the type of eruption that occurred at Mauna Loa.
  • Thick and sticky magma makes it difficult for gases to escape consistently. This causes pressure to build up until a breaking point is reached.
  • At this point, the gases all escape violently and simultaneously, resulting in an explosion.
  • Lava blasts into the air, breaking up into tephra-like fragments. Mount Vesuvius, which destroyed Pompeii, is an example of an explosive volcano.


As urbanisation and globalisation increase, volcanoes have a greater impact on man and material. The effects have an impact on flora, fauna, and global warming, which can hasten climate change.