What Is the Word for a Volcano That Is Never Going to Erupt Again

What is a Volcano?
A volcano is an opening in the Globe'due south crust that allows magma, ash and gasses to erupt from beneath the surface. It is made up of a magma chamber, a vent, a crater and a cone shaped mountain made of layers of ash and lava.

Magma chamber → Magma from the Earth's mantle collects in a large underground pool. The magma in a magma chamber is nether great force per unit area trying to forcefulness its way upwards to the surface.

Vent → The magma forces its way upwards through the vent which is like a chimney for the volcano. There is the main vent simply there tin also be secondary vents on the side or flank of the volcano. These secondary vents produce secondary cones on the flank of the volcano.

Crater → The crater or caldera  is the basin shaped feature on top of the volcano that the magma from the vent erupts form.

Cone shaped mount → The majority of volcanoes are cone shaped mountains. They are formed of alternating layers of lava and ash from multiple eruptions. Equally the volcano erupts a layer of lava forms, the ash cloud formed during the eruption later cools and falls, this is known every bit pyroclastic menstruation. This forms a layer of ash on superlative of  the lava. This process is repeated each fourth dimension the volcano erupts.

What is the difference betwixt magma and lava? Magma is molten stone below the surface of the Earth'south crust, when this molten rock reaches the surface of the globe is is and so chosen lava.

Stages of a Volcano's life.
There are 3 types of volcano based on the different stages in the volcano'due south life. These are Agile, Dormant and Extinct.

Active → Agile volcanoes erupt regularly examples of active volcanoes are Kīlauea in Hawaii, Mount Etna in Italian republic and Mount Stromboli as well in Italy which has been erupting almost constantly for the last 2000 years.
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Fallow → Fallow volcanoes are volcanoes that have not erupted in a long time but are expected to erupt again in the time to come. Examples of fallow volcanoes are Mount Kilimanjaro, Tanzania, Africa and Mount Fuji in Japan.
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Extinct → Extinct volcanoes are those which take not erupted in human history.  Examples of extinct volcanoes are Mount Thielsen in Oregon in the Usa and Mountain Slemish in Co. Antrim.

Where do Volcanoes occur?
The bulk of volcanoes occur at plate boundaries. They tin occur where plates carve up, an example of this is Iceland. Here volcanoes are formed by the North American and Eurasian plates pulling apart. (see divergent plate boundaries)

 They can besides occur where plates collide. Mountain Etna is formed by the subduction of the African plate under the Eurasian plate. The melting of the subducted plate causes an increment in pressure which leads to the formation of a magma sleeping room and in plow a volcano.

Image credit: National Geographic

    Volcanoes can also form at areas known every bit Hot-Spots. Hotspots are caused by magma of increased temperature from a drapery plume. This hot magma melts through the rock of the Earth's crust and rises through the cracks to form a volcano.

 452 of the world'due south volcanoes can exist found in what is known as the Pacific Band of Fire. this is an area of intense volcanic activity due to plate tectonics. 75% of the world agile and dormant volcanoes tin be found here.

What causes volcanoes to erupt?
Rock from subducted plates melts to form molten magma which pushes its way towards the surface forming a magma chamber. Gasses that have been dissolved in the magma aggrandize causing a massive increase in pressure level. This increment in pressure causes the magma to rise and force its mode through cracks/fissures in the volcano above. As information technology reaches the surface the pressure level is released and an eruption occurs. During an eruption volcanic ash, rock particles, dust, gasses and lava are all ejected.

 How violent the eruption is depends on the amount of silica present in the magma. Silica produces a thicker magma that is better at trapping gasses. The more than gas present the greater the pressure. Therefore the more silica present in the magma the more than tearing the eruption volition be.

Types of lava and their effect on the volcano construction
There are two types of lava, acidic and bones.
Acidic lava has a high silica content and this makes it thicker. This thick lava doesn't travel far and due to the high level of dissolved gas it has violent eruptions. Combined these cause the volcano to have a steep sided cone. These are known as Cone Volcanoes.

Basic lava contains less silica, this allows the gasses to escape and gives a runny lava. Eruptions of this type of lava a gentler and this along with it being runny allows the lava to menstruation further. Volcanoes of this type of lava volition have gently sloping sides. They are known as Shield volcanoes.
For more than information on the types and shapes of volcanoes see Tulane Academy website

How can we forecast volcanic activity?
By studying the type of materials and distribution of deposits geologists tin larn a lot about the activeness of volcanoes.
Eruptions tin can be predicted in a number of ways:
Tiltmeters are very sensitive devices that are used to identify any bulging of the sides of a volcano. Increased pressure that causes the volcano'south sides to bulge out indicating an eruption may be about to happen.

Gases or steam coming out of vents in the volcano or the appearance of geysers could suggest an eruption will soon follow.
Seismometers are used to discover vibrations in the rock. These could exist acquired past the motion of the magma or the not bad of rocks due to increased hea both of these would indicate an eruption being imminent.
For real time monitinrg of the worlds volcanoes see the Globe Organisation of Volcanic Observatories website

 Ireland and Volcanoes
Ireland is not known for its high level volcanic activeness in recent history simply past studying the landscape volcanoes from hundreds of millions of years ago can be withal be seen.

 There are a number of extinct volcanoes in Republic of ireland these include Slieve Gullion in County Armagh, Croghan Hill in Canton Offaly, Mountain Slemish in Canton Antrim, Lambay Isle in Dublin and Loch Na Fooey in Canton Galway. These volcanoes are all extinct with the last eruption was approximately sixty million years agone.

 Today the Geological Survey continues to place previously undiscovered volcanoes subconscious beneath the surface of Republic of ireland. To learn more well-nigh these Geophysical surveys visit the Tellus folio.

  Other volcanic activity can also exist identified here in Republic of ireland. One of the world's nearly famous Geoheritage sites The Giant's Causeway, is a event of volcanic activity. Approximately lx one thousand thousand years ago Antrim was at the heart of intense volcanic activity, magma from below the Earth's surface forced its way up through fissures in the stone and formed a huge lava plateau. As this lava apace cooled it contracted forming the famous hexagonal columns.
To larn more on the Giant's causeway website.

Image credit: Ireland.com

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Source: https://www.gsi.ie/en-ie/geoscience-topics/natural-hazards/Pages/Volcanoes.aspx