Quick Answer: Why Do Some Volcanoes Erupt Violently While Others Erupt Quietly?

Do shield volcanoes erupt violently?

Eruptions at shield volcanoes are only explosive if water somehow gets into the vent , otherwise they are characterized by low-explosivity fountaining that forms cinder cones and spatter cones at the vent, however, 90% of the volcano is lava rather than pyroclastic material.

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Which lava has the highest viscosity?

rhyoliticThe magma that has the highest viscosity is rhyolitic magma.

Which type of magma erupts most explosively?

Explosive eruptions are favored by high gas content & high viscosity magmas (andesitic to rhyolitic magmas). The explosive bursting of bubbles fragments the magma into clots of liquid that cool as they fall through the air.

What is the most dangerous volcano in the world today?

Vesuvius volcanoThe quick answer: Vesuvius volcano in the Gulf of Naples, Italy. The reason is that Vesuvius’ typical eruptions are very explosive and the slopes of the volcano and immediate area surrounding the volcano are extremely densely populated; even the city of Naples is only about 20 km away from the volcano.

Why is the stratovolcano the most dangerous?

Of all the volcanoes on Earth, stratovolcanoes are the most dangerous. They can erupt with little warning, releasing enormous amounts of material. … As we saw with Mount Saint Helens, they can blast out material from the side, creating pyroclastic flows the hurtle down the volcano’s flanks at enormous speeds.

What causes a volcano to erupt violently?

In volcanology, an explosive eruption is a volcanic eruption of the most violent type. … Such eruptions result when sufficient gas has dissolved under pressure within a viscous magma such that expelled lava violently froths into volcanic ash when pressure is suddenly lowered at the vent.

Why do volcanoes erupt in different ways?

Volcanoes erupt when molten rock called magma rises to the surface. Magma is formed when the earth’s mantle melts. … If magma is thick, gas bubbles cannot easily escape and pressure builds up as the magma rises. When the pressure is too much an explosive eruption can happen, which can be dangerous and destructive.

Why are rhyolitic eruptions the most explosive?

Explosive eruptions are favored by high gas content and high viscosity (andesitic to rhyolitic magmas). Explosive bursting of bubbles will fragment the magma into clots of liquid that will cool as they fall through the air.

What are the characteristics of a quiet eruption?

Quiet Eruptions Volcanoes that have very hot, low-silica magma generally erupt quietly. In a quiet eruption, lava erupts in a stream of low-viscosity lava, called a lava flow. Lava flows from a quiet eruption can travel for great distances.

Which volcanoes are more likely to explode the ones with thick lava or thin lava?

The lava that flows from both types of eruptions is very hot, thin, and runny which allows for fast flowing lava flows. The main difference lies in the fact that most Hawaiian eruptions have the greatest quantity of lava pouring out of the main vent at the volcano’s summit, not along side fissures.

Which type of volcano is the most dangerous?

Because they form in a system of underground conduits, stratovolcanoes may blow out the sides of the cone as well as the summit crater. Stratovolcanoes are considered the most violent. Mount St. Helens, in Washington state, is a stratovolcano that erupted on May 18, 1980.