Volcanoes

The volcano is known as one of the most destructive forces in human history. Yet we can not reject a vision of how the explosion of the volcano.

What is a volcano?

The volcano is an opening through which molten rock called magma rises from the earth's land surface. Magma eruption of the volcano lava is known, and is a material that creates a cone around the Vent.

The volcano is active, the eruption of lava, creating seismic activity or natural gas release. Sleeping volcano, cut a very long period, but may break out again in the future. If the volcano idling more than 10,000 years, is known to be extinct.

Volcanoes may be different in appearance, a perfect cone shape, and other deep pits filled with water. Volcanoes form shows the type and size of the volcano, which is governed by the properties and composition of magma. Size, style and frequency of outbreaks vary widely, but these factors help to create a volcano.

How volcanoes formed ?

Volcanoes occur where the majority of the two plates together. When two plates move, but is a gap, hot molten rock - called lava - is growing between them. The volcano is the nature of the sea and the most invisible. If the amount is large enough, excess magma of the ocean and the island created.If two plates collide and one plate forced under another plate, which makes its first cuimilte melt and rising magma. But after a few volcanoes in the world who made this, but their outbreaks are the most violent and dangerous. Sometimes it is also a volcano in the middle of the plate, so-called hotspots. These are things involved in a warm blanket.

Three main types of volcanoes listed below, which are made in various forms: --

Shield volcano

Shield volcanoes are almost entirely basalt. When the magma is very hot and liquid, and is ready to run gas to a wide range of magma to the Earth's surface is composed of lava flows. Shield volcanoes are broad, cruinneachán transitions-in the form of a series of fluid lava flows on the surface and cool. As the lava flow, which can easily move down the slope gradually significantly from volcanic vents.

Composite Volcano

Alternating layers of lava, forming a volcano. That is why they are called composite volcano. They are also known as strato-volcanoes. Composite volcanoes tend to erupt in an explosive manner. Blocked when the viscous magma rises to the surface, it usually clogs the crater and the crater pipelines. Lead to increased pressure, resulting in an explosive outbreak. Although Strato volcanoes are usually large and conical, we have several forms: a helmet concave, pyramidal, convex-concave shape, the disaster of nested caldera, more summits, elongated along the cracks.

Caldera

There is a huge magma breaks the surface of the sub-divisions of the magma. Magma away leaving cavities beneath the surface and the top collapses in the form of the caldera. Harbor is a continuation of the circular depression and, as a rule, the order of several kilometers or more in diameter. Lava erupted from the caldera of the volcano is very viscous and generally cold with temperatures between 650 ° C to +800 ° C and magma Rhyolitic. Although the caldera is rare, they are most dangerous. Volcanic hazards from this type of volcanic crater tsunami, large volcanic surges and ash wide.