What are the Characteristics of a Volcanic Mountain?

The five characteristics of a Volcanic mountain are –

  1. Eruption
  2. Explosion
  3. Expansion
  4. Emulsification
  5. Crater

when the mountain is in an active state, the temperature is extremely hot with temperature ranging from 600-1000 Celsius . But when the mountain is dominant, there no reactions taking place. The internal temperatures between the plates and rocks within the stratosphere layers of such mountains are not as hot to cause any explosions or eruptions.

What are the definition of the characteristics of a volcanic mountain?  

Eruption: Occurs when a volcanic mountain becomes active and eject lava, ashes and chemical gases.

Explosion: Occurs when a volcanic mountain explodes with thrusts of rocks, fractured stratoplates, molten magma, and bombs producing extreme heats, red hot lava with a mixture of hot water, thick smoke forming combustion of mixed clouds, debris and ash bursting into the atmosphere.


Expansion: Occurs when a volcanic mountain expands due to molten magma, divided stratoplates, extreme heat, debris causing cooling of rushing lava to form solidified magmalike, expanding land surface of the mountain. During volcanic eruption, the temperature is very hot and can get up to 600oC. Expanded landform areas like this are common in Hawaii.


Uplift or Inflation: Occurs when a mass of new lava rises to the surface, it pushes the old rock aside and upward making a bulge or uplift on the surface. The process is often called inflation, because the expansion of a volcano due to the lava pushing up inside is similar to inflating a balloon by blowing new air into it. The inflation of a volcano is measured in several ways: by tilt meters that measure the angle of the ground surface, by laser ranging using mirrors placed on the mountain, and by precision surveys using aerial photographs.

Emulsification: Occurs when a volcanic mountain becomes active, fussing out molten lava which is combine with chemical gases and formation of aqueous fluids with a higher percent of oil. These emulsion fluids gets trapped within very cold layers of the landforms ready to be drilled and exported. An emulsion is a temporarily stable mixture of immiscible fluids, such as oil and water, achieved by finely dividing phase of oil from water. Common emulsions can be oil suspended in water or aqueous phase (o/w) or water suspended in oil (w/o). There also can be more complex systems, such as oil in water in oil (o/w/o). During instances like this, filtration of oil from the collected mixture water is then process to eliminate water.

Craters: Is a bowl-shaped depression formed by a volcanic eruption or impact of a meteorite.

Volcanic Craters

Volcanic activity often creates craters. Some volcanic craters are deep and have steep sides. Others are wide and shallow.

A crater is not the same thing as a caldera. Craters are formed by the outward explosion of rocks and other materials from a volcano. Calderas are formed by the inward collapse of a volcano’s magma chamber. Craters are usually much smaller features than calderas, and calderas are sometimes considered giant craters.

Craters at the top of volcanoes are called summit craters. Summit craters are where volcanic material is at or near the Earth’s surface. Volcanoes may have one summit crater, such as Mount Fuji in Japan. Or they may have several. Mount Etna, in Italy, has four.

Some volcanoes are calm enough that scientists can get close to the lava in the summit crater. Mount Erebus, a volcano in Antarctica, has a lava lake in its summit crater. Lava lakes are where magma has bubbled up to the surface. Volcanologists can fly over Mount Erebus’ summit crater to see how the lava lake is behaving and predict future behavior.

Volcanic material in some summit craters is near the surface, but not visible. Although Mount Fuji is an active volcano and magma and gases sit below the summit crater, the risk of an eruption is very low. Mount Fuji, Japan’s highest mountain, is one of the most popular places in the country to hike.

Craters that form on the sides of volcanoes are called flank craters. Eruptions from flank craters can be much more dangerous than eruptions from summit craters. Flank craters can form at lower altitudes than summit craters, near hillside towns. Lava, gas, rocks, and other material ejected from a flank crater can rush down the side of a mountain in a phenomenon called a pyroclastic flow. Mount Etna, one of the most active volcanoes in Europe, has had a number of dangerous eruptions. In 1928, the eruption of a flank crater completely destroyed the village of Mascali.

Over a long period of time, small and non-explosive eruptions may fill a volcanic crater with new material. At Mount St. Helens, in the U.S. state of Washington, for example, a large crater formed when a major eruption in 1980 tore off 400 meters (1,300 feet) of the mountaintop. Soon after, smaller eruptions began piling up lava and volcanic ash on the crater floor, slowly rebuilding the mountain.

Volcanoes can also create craters when the magma comes into contact with water. Magma flowing or bubbling beneath a volcano can sometimes interact with groundwater in the area. When this happens, a small explosion occurs and a crater forms around the explosion. This type of volcanic crater is called a maar.

Often, a maar will fill with water and become a shallow crater lake. The thin floors of these lakes are actually the roofs of volcanic vents, waiting to come into explosive contact with water once again. The Seward Peninsula, in the U.S. state of Alaska, is filled with maars that form as magma encounters not groundwater, but permafrost.

Explosion Craters

A third type of crater is formed by an explosion. When materials or chemicals explode, the explosion displaces all the material around it. The debris often lands in a circular pattern around the site of the explosion, creating a crater.

Explosions can be natural or artificial. The explosion that creates a maar, for example, occurs naturally when water interacts with superhot magma from a volcano. Maars are a type of explosion crater as well as a volcanic crater.

Artificial explosions that form craters usually happen underground. The explosion pulverizes or vaporizes material underground, and the earth above sinks. Craters formed by underground explosions are called subsidence craters. (Craters formed by explosions at or near the surface of the Earth are simply called explosion craters.)

Drilling underground for oil and natural gas can lead to explosions and subsidence craters. Machinery can sometimes encounter a pocket of natural gas that is under extremely high pressure. When drilling machinery punctures the pocket of natural gas, the overlying rock layers may not be able to contain it. Like an enormous balloon, the gas pocket pops. As the gas is released in the explosion, a crater forms in the empty space.

A specific type of subsidence crater is formed by an underground nuclear explosion. Most nuclear testing is conducted in underground facilities. As the explosion displaces massive amounts of material, the earth above it sinks. In fact, subsidence craters caused by underground nuclear explosions are sometimes called sinks. The Nevada Test Site, in the remote deserts of the U.S. state of Nevada, is pockmarked with nuclear subsidence craters.

The debris in and around nuclear subsidence craters often comes into contact with radioactive material. For this reason, access to these sites is restricted.

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