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Volcanic Activity

Volcanoes appear when magma is forced up through cracks in the Earth's crust. Learn about different types of volcanoes and their activities.

Volcanoes are one of the fascinating geological features on Earth, and their volcanic activity fascinates scientists and the general public alike. From the explosive eruptions that make headlines to the ongoing geothermal activity at some volcanoes, volcanoes constantly change and surprise us. 

Volcanoes are a natural part of the Earth’s landscape, and they are responsible for some of the world’s most scenic settings. However, volcanoes can also be dangerous – and knowing what to do in the event of a volcanic eruption is essential.

What is a Volcano?

When magma and ash escape through a crack on Earth’s surface, a volcano is formed. The molten rock becomes solid as they cool, making a volcano. Volcanoes can produce mountains over millions of years. There are three types of volcanoes: cinder cone, composite cone, and shield volcano.

How do scientists study Volcanoes?

Scientists study volcanoes in some ways, including direct observation, studying records of past eruptions, and monitoring seismic activity. By studying the behaviour of volcanoes, scientists can learn about the inner workings of these mountains and better predict when they might erupt. 

Scientists study volcanoes by looking at their records of past eruptions. It can tell us how often they erupt and what kind of damage they can cause. Scientists also monitor seismic activity around volcanoes. It can help them predict eruptions and assess the level of danger a volcano poses to people and property.

What are the dangers of Volcanic eruptions?

Volcanoes can pose a serious threat to both humans and their environment. One of the biggest dangers is the release of ash and gas into the atmosphere. These can cause respiratory problems and other health issues and disrupt air travel and cause other economic damage. 

Another danger is the release of lava, which can incinerate anything in its path. Volcanic eruptions can also trigger mudslides and flooding. It’s important to be aware of these dangers and be prepared if a volcano is located near you.

Effects Of Volcanic Activities

There are numerous effects of volcanic activity, some more immediate and some more long-term. Immediate effects of volcanic activity can include ashfall, which can block sunlight and cause respiratory issues, and lahars, which are dangerous fast-flowing rivers of mud and water. Long-term effects of volcanic activity can include the loss of homes, crops, and infrastructure and the release of harmful gases and particles into the atmosphere.

Volcanic activity can also have significant social and economic effects. For example, it can lead to the displacement of populations, loss of access to resources, and loss of income. In some cases, it can also cause a humanitarian crisis. Given the potential for such widespread damage, it is important to be aware of the signs and symptoms of volcanic activity and take appropriate safety precautions.

How can you prepare of a Volcanic eruption?

There’s no way to 100% prepare for a volcanic eruption, but there are some steps you can take to help minimise the risks. Follow news reports and heed any warnings or evacuation orders issued. Keep an emergency kit packed and ready to go, and have a plan for what you’ll do if an eruption occurs. If you live in an area near a volcano, be aware of the dangers and know what to do if an eruption is detected.

Types of Volcanic activities

There are many types of volcanic activity, but the three most common are 

  • Explosive eruptions 
  • Effusive eruptions 
  • Lahar flows

Explosive Eruption – Explosive eruptions release large amounts of ash, rocks, and hot gas. They can cause significant damage to people and property and be deadly if not prevented.

Effusive Eruption – Effusive eruptions are less violent than explosive eruptions and are typified by the eruption of a lava flow that is thick, dense, and has a high viscosity. This eruption is often accompanied by a roar and is often more impressive than an explosive eruption.

Lahar Flows – Lahar flows are a type of volcanic activity characterised by a fast-moving flow of water, mud, and rock that can reach speeds of up to 250 mph. They can be destructive and can cause significant damage to property and communities.

Conclusion –

The biggest volcanic eruption in history was the colossal eruption of Mount Tambora on Sumbawa Island in Indonesia on April 10, 1815. This eruption was one of the largest recorded histories, with a Volcanic Explosivity Index (VEI) of 7. The eruption ejected an estimated 100 cubic kilometres (24 cubic miles) of dacite magma and created a caldera 6 kilometres (3.7 miles) wide and 1 kilometre (0.6 miles) deep. 

The force of the eruption caused a tsunami that killed an estimated 10,000 people in Sumbawa and neighbouring Java. The eruption also had a significant impact on world weather, causing what is known as the “year without a summer” in North America and Europe in 1816.

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Frequently Asked Questions

Get answers to the most common queries related to the UPSC Examination Preparation.

How long does it take for a volcano to erupt?

Ans. Activity at a volcano varies from day to day, but it can take up to two weeks for the volcano to become active....Read full

What are the types of volcanic eruptions?

Ans. Volcanic eruptions can be classified into two main types: explosive and effusive. Explosive eruptions are chara...Read full

How does a volcano work?

Ans. Volcanics are formed when the Earth’s mantle melts. Magma rises to the surface and forms a volcano when i...Read full

How often do volcanoes erupt?

Ans. The Earth’s volcanoes erupt on average every 500,000 years.

What is a lava flow?

Ans. A lava flow is a volcanic eruption characterised by a slow-moving, thick stream of molten rock, ash, and someti...Read full