How does energy build up before a volcano erupts?

A volcano erupts when gases build to an inescapable high pressure. The gas pushes magma and ash through the cone of the volcano causing an eruption.

because the cynder, ashes and lava build around the volcano.and when the lava cools around it, it becomes a hard crust

Yes, when an underwater volcano erupts, the lava is cooled in the water forming stone, this can build up to form an island. The Hawaiian islands are a good example.

Pressure of gases and magma build up inside the volcano until it erupts.

When a volcano erupts, it then could build up more land, due to the lava drying up. Also it can damage the land, crops, vegetation, vice-versa. -TheBestAnswers.

1. Magma in the magma chamber begins to build up 2. Magma goes up into the pipe 3. The volcano erupts

When a volcano erupts and the lava hardens it can build up under water and over time, if enough builds up, the result will be an island

Before a Volcano "erupts" the mountain and surrounding areas will experience seismic activity (Earthquakes) for hours, days, weeks and even months before the initial eruption. Also Vulcanologist monitor gas emissions from the volcano to see if there is a build up gas. And of course there many be some steam/smoke coming from the volcano (Does not have to be from the cone of the volcano, can be from vents on the side or further down the volcano!) In the case of Mt St Helens - A "DOME" appeared on the side of the mountain, this was a build up of Magma further down the mountain slope in which grew larger by the day until the initial and catastrophic eruption.

Mountains are only formed around volcanoes that erupt quite often this is because when a volcano erupts it lets out volcanic bombs what solidify to create new land. By lots of volcanic bombs building up overtime around the volcano can create a mountain.EXTRA HELPFUL!

cinder cone volcanoes: consist of primarily erupted volcanic ash and rock fragments, or cinders. When the volcano erupts the ash and rock are ejected onto the mountain. As this process continues the volcano "grows" higher because of the debris build up.

A rhyolite volcano is a volcano that erupts rhyolitic lava or pyroclasitc material. Rhyolite is an igneous rock formed from the eruption of extremely viscous silica rich material. Eruptions involving rhyolite can be extremely large and violent. In some cases, however, rhyolite can build into lava domes or form thick, extremely slow lava flows.

If a volcano has not erupted in 600 years that probably means magma has been building up for all that time. If it erupts, it could eject all 600 years worth of material, which could amount to several cubic miles. Such and eruption would be very violent, producing enormous clouds of ash and pyroclastic flows. By contrast a volcano that erupts frequently has less of an opportunity tu build up a large volume of magma.

NO, it erupts because of the build-up of pressure in the magma containment. When the pressure becomes so strong that there is no other way to release it, the lava rushes up and blows off the top of the volcano.

A volcano forms a mountain as ash and/or lava build up over time from successive eruptions.

A build up of hot water forms underground and erupts ubruptly.

A volcano erupts because there is mass pressure under it. In a volcano there is hot, melted rock called lava. The hot lava produces gasses that build up underground until there is too much for the rock to contain, that makes the eruption. When there is too much, it bursts the volcano. There are two types of eruptions. Non explosive and explosive. When they are explosive, it is caused by clouds of hot debris and gases.

When the lava reaches the earth's surface it starts to cool and harden into rock. This happens every time the volcano erupts. Eventually the cooled down layers build up thus adding to the size of the volcano. To make it easier to understand, imagine grabbing a handful of sand and pouring it back onto the ground, grab another handful and pour it onto the existing mound, repeat this and then notice how it grows, this is the same principal as the volcano.

magma rises up out of a volcano by the build up of pressure

no they cant, it erupts because of the build-up of pressure

If a tall shield volcano has been built from many eruptions over thousands of years the magma that helped build this volcano contained

The ash and lava that a volcano erupts can build up the land, which include the mountain of the volcano itself. In the case of underwater volcanoes, this process can created new islands. At the same time, the slopes of volcanoes are often unstable and prone to landslides, which are destructive. Very large eruptions can form large explosion craters and may even result in the volcano collapsing to forma depression called a caldera.

They didn't know it was a volcano. So they just went on with their lives.

Deep beneath every volcano lies a reservoir of molten rock called magma chamber.Volcanoes erupt when the build-up of pressure in the chamber forces magma up a pipe or vent,to the surface ,where it erupts as lava.Solidified fragments of lava are ejected as clouds of ash.Succesive flows of lava and ash build up a volcano cone.Secondary cones occur at the exit of the side vents.Vents where steam and gas emerge are called fumeroles.Solidified magma forms dykes,laccoliths and sills.Superheated ash clouds occur during particularly explosive eruption.

Why electric? Cant people these days use the simple old-fasioned way of making a volcano?

There are six main types of volcanoes. Cinder cone, caldera, composite, shield, submarine and lava dome volcano. Basically though, a volcano forms when either a continental plate or oceanic plate subducts under another plate where, due to extreme temperaratures the rock melts. This forms cracks in the plate. Magma will forces its way up through cracks in the earths crust. When it reaches the surface it builds up slowly. when the volcano erupts ash, magma and debris fall around the volcanoes cone. these eruptions will slowly build up the volcano.