A volcano is a land-form, a mountain, where molten rocks erupt through the surface of the planet. The volcano mountain opens downwards to a pool of molten rocks below the surface of the earth. When the pressure builds up in the earth’s crust, eruptions occur. Gasses and rock shoots up through the opening and spill over or fill the air with lava fragments. The volcano eruption can cause lateral blasts, hot ash and lava flow etc.

There are about 1,500 potentially active volcanoes worldwide, aside from the continuous belts of volcanoes on the ocean floor at spreading centers like the Mid Atlantic ridge. About 500 of those 1,500 volcanoes have erupted in historical time. Many of those are located along the Pacific Rim in what is known as the “Ring of fire.” In the United States, volcanoes in the Cascade Range and Alaska are part of the Ring, while Hawaiian volcanoes form over a ‘hot spot’ near the center of the Ring. There are 169 Potentially active volcanoes in the United States. The U.S. Geological Survey assesses and monitors hazards at volcanoes within the United States and its territories.



Mauna Loa is the biggest volcano on Earth. It is 9,170 meters tall. It is a shield volcano. Mauna Loa shares is a hot spot in the Pacific plate. It is Situated in Hawaii Volcanoes National Park, Mauna Loa is the world’s largest volcano. It’s outrageously active, chalking up 33 eruptions since 1843 when it had a big blow out. Neighbouring Kilauea is smaller but just as energetic. You can drive around the summit, as long as there are no active lava flows.


Mount Fuji has a symmetric cone and for a few months its summit is covered in snow. It is an active volcano. Mount Fuji is a stratovolcano. It is 3,776 meters tall. It is the tallest peak in Japan. It lies on the Eurasia tectonic plate. The lava from Mount Fuji’s eruption is basaltic. A perfectly shaped volcano with a conical form and pretty snow-capped peak, Mount Fuji is japan’s most popular and visited tourist attraction, and it’s one of the most famous volcanoes around the world. It’s currently active, though last erupted in 1708, so should be safe enough to scale – as many do in summer months. If you’re feeling nervous check it out from the security of a bullet train between Tokyo and Yokohama.

Yoshida, Mount Fuji, Japan


Mayon Volcano is an active stratovolcano in the Philippines. It has steep slopes that form a symmetrical classic volcano. It is 8,081 feet tall. It is located on a convergent boundary between the Eurasian and Philippine plate. The lava from Mayon Volcano is pyroclastic.


Mount St. Helens erupted in 1980 and was one of the most devastating eruption in the USA. It is an active stratovolcano located in Skamania County, Washington. Mount St. Helens is part of the Cascade Mountain range. It’s 8,366 feet tall. It consists of lava rock interlayered with ash, pumice, and other deposits. The mountain includes layers of basalt and andesite through which several domes of dacite lava have erupted. Mount St Helens is on the plate boundary between the Juan de Fuca plate and North American plate. Mount St Helens is responsible for the most catastrophic eruption in the US: in 1980, the side of the mountain blasted out over miles and miles of expensive timberland, destroying towns, highways and bridges and killing over 50 People.


Mount Bromo and Mount Semeru, East Java, Both volcanoes are active and located in Bromo Tengger Semeru National Park, creating a landscape of a different planet. Semeru is taller and expels smoke, while Bromo fumes constantly. Mount Bromo is 7,641 feet tall and Mount Semeru is 12,060 feet tall. Mount Bromo is a small but active volcanic cinder and Mount Semeru is an active stratovolcano. They are both on the Eurasian plate. Mount Semeru is made up of layers of andesitic deposits. Mount Bromo is a small pyroclastic cone and all recent lava flows are andesitic.


Etna, Catania, Sicily. Mount Etna is Europe’s tallest and the most popular volcano. Roman poet Virgil said it is a home of a mythological god Hephaestus and a one-eyed monster Cyclops. Etna is an active stratovolcano on the east coast of Sicily, Italy, in the Metropolitan City of Catania. It is 10,991 feet tall. It rests on the subduction boundary where the African tectonic plate is being pushed under the Eurasian plate. It has been for active for 500,000 years and creates eruptions of Basaltic lava. Sicily harbours Europe’s tallest active volcano, Etna,is located outside the city of Catania. Visitors can make their way to the steaming, smoking summit.The temperature at the top drops considerably, so take a few layers with you. Mount Etna erupted as recently as in February 2021 and left a shower of ash that reached Catania, adding to the fact that it is one of the most active volcanoes in the world.

Mount Etna, Italy

Types of Volcanoes :

Volcanoes are grouped into four types:

  • Cinder cones
  • Composite volcanoes
  • Shield volcanoes
  • Lava volcanoes

Cinder Cones:

Cinder cones are circular or oval cones made up of small fragments of lava from a single vent that have been blown up. Cinder cones result from eruptions of mostly small pieces of scoria and pyroclastics that build up around the vent.

Cinder cones

Composite Volcano :

Composite volcanoes are steep-sided volcanoes composed of many layers of volcanic rocks, usually made from high-viscosity lava, ash and rock debris. These types of volcanoes are tall conical mountains composed of lava flows and other ejects in alternate layers. Composite volcanoes are made of cinders, ash, and lava. Cinders and ash pile on top of each other, lava flows on top of the ash, where it cools and hardens, and then the process repeats.

Composite volcanoes

Shield Volcano :

Shield volcanoes are volcanoes shaped like a bowl or shield in the middle with long gentle slopes made by basaltic lava flows. These are formed by the eruption of low-viscosity lava that can flow a great distance from a vent.They generally do not explode catastrophically. Since low-viscosity magma is typically low in silica, shield volcanoes are more common in oceanic than continental settings. The Hawaiian volcanic chain is a series of shield cones, and they are common in Iceland.

Shield volcanoes

Lava Domes :

Lava domes are formed when erupting lava is too thick to flow and makes a steep-sided mound as the lava piles up near the volcanic vent. They are built by slow eruptions of highly viscous lava. They are sometimes formed within the crater of a previous volcanic eruption. Like a composite volcano, they can produce violent, explosive eruptions, but their lava generally does not flow far from the originating vent

Lava domes


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