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You have seen the ways in which the volcanoes erupt?? Lets enter the world of volcano facts. Volcanoes are not always the simple cones that one usually associates with outpourings of red hot, molten rock. In fact, eruptions vary a great deal in the type of products that are spewed out, in their intensity, and in the form which the volcanic vent takes.
First of all, there is the type which is known as the fissure eruption. This is a simple one to describe. Here, a flood of lava pours out of a crack in the earth's crust and flows very freely. When it cools, it hardens into an almost flat sheet. This type is known as Icelandic type, because of the type of lava flows commonly found there.
In the Hawaiian type of volcano or the volcano in iceland, so called for obvious reasons, lava pours out of a pit like crater, and gas is quietly released most of the time. Occasionally, however, there is a sudden spurt of the volcanic gases blowing out a spray of glowing, burning droplets of lava. The well known Pele's hair is caused by these droplets being caught in the wind and stretched into threads.
Biggest Volcano Eruptions
If the lava cannot flow easily (and this occurs when the composition of the magma is ritcher in Silica), the gases have more difficulty in bubbling off. They are only released when the pressure builds up enough to force the gases out. In this kind of eruption, which is known as the Strombolian type after Stromboli, Sicily, the volcano erupts from time to time carrying lumps of lava or volcanic bombs. Sometimes, there are also lava flows.
If the lava is very thick and almost solid, great gas pressure is needed before it is released. When it does erupt, it does so with explosive and terrible force, so that hot ash and fragments of lava are thrown high into the air. This is known as the Vulcanian type, and the characteristic cone is developed. There are different types of central volcanic types, that is, where the eruptions are from one main centres.
Vulcanology is a very complex study, and for the most adventurous, can be extremely dangerous one, involving climbing to the very top of an active volcano. Under these conditions, even if the volcano is not actually erupting, the ground may be so hot that it burns the shoes of the scientists and the gases may be almost suffocating. Workers have actually lokked into open crates into the bubbling, burning lava below.