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Why do eruptions in Hawaii differ from the Mt. St. Helen's eruption?
Wiki User
∙ 8y ago
The magma of the Hawaiian volcanoes has a basaltic composition, which means it has a low viscosity (it flows easily) and so can erupt easily without needing too much force behind it. This low viscosity magma cannot hold very much gas and so erupts effusively By contrast, the magma involved in the 1980 eruption of Mount St Helens had a dacitic composition, which has an extremely high viscosity. The high viscosity allows large mounts of gas to be stored in the magma under pressure. When the magma was exposed to lower pressure near the surface, the gas was released and expanded explosively, blasting the magma into ash and pumice.
Annabel Jacobs
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Why do eruptions in Hawaii differ from mt St. Helens eruptions?
The magma of the Hawaiian volcanoes has a basaltic composition, which means it has a low viscosity (it flows easily) and so can erupt easily without needing too much force behind it. This low viscosity magma cannot hold very much gas and so erupts effusively By contrast, the magma involved in the 1980 eruption of Mount St Helens had a dacitic composition, which has an extremely high viscosity. The high viscosity allows large mounts of gas to be stored in the magma under pressure. When the magma was exposed to lower pressure near the surface, the gas was released and expanded explosively, blasting the magma into ash and pumice.
Why do eruptions in Hawaii differ from Mt. St. Helens eruption?
The magma of the Hawaiian volcanoes has a basaltic composition, which means it has a low viscosity (it flows easily) and so can erupt easily without needing too much force behind it. This low viscosity magma cannot hold very much gas and so erupts effusively By contrast, the magma involved in the 1980 eruption of Mount St Helens had a dacitic composition, which has an extremely high viscosity. The high viscosity allows large mounts of gas to be stored in the magma under pressure. When the magma was exposed to lower pressure near the surface, the gas was released and expanded explosively, blasting the magma into ash and pumice.
How did the damage caused by the eruption of mt Pinatubo differ from the damage caused by the eruptions of mt st Helen?
Much of the damage caused by Mount St Helens was blast damage from the initial explosion. This explosion was projected northward out of the side of the volcano, unlike other explosions, which have most of their force directed upward.Most of Pinatubo's damage was caused by ashfall, which was exacerbated by heavy rain from Typhoon Yunya, which impacted the Philippines during the eruption.
How volcanic eruptions differ from earthquakes?
volcanic eruptions are hotter
Why do volcanic eruptions differ?
The main cause of differences in volcanic eruption characteristics is due to the viscosity of the magma. High viscosity magmas are high in sticky silica which traps gas and produces explosive eruptions. Low viscosity magmas are low in silica and produce eruptions with far less energetic characteristics.
How do two types of volcanic eruptions differ?
no
Why are eruptions deep in the ocean calmer than eruptions on land?
Eruptions in the deep ocean differ from eruptions on land for several reasons. The deep ocean eruptions are often tmes and depending on cause as well as location from basaltic magma. This type of magma is not known for its explosivity. The magma is the type that build the hawaiian volcanoes and more or less when erupting flows (Although it is capable of explosive eruptions). The other major factor is for an explosive eruption to be generated the magma must be very viscous to allow the build up of gas bubbles. The second half and what actually causes the explosive eruption is the explosive release of this gas. When an eruption occurs in the deep ocean it is not explosive due to the fact that the gas cannot decompress from the magma explosively due to the extreme pressures exerted by the water at such depth. Even if it were the right type of volcano that could generate explosive eruptions with the pressure it would be unable to do such a thing.
How is Hawaii differ from the other states?
It is the only state that is an island
How is Hawaii differ from other states?
It is a string of islands, not like other states! :) ^_^
How do you think the climates os Hawaii and Alaska differ?
Well Hawaii has tropical weather. Alaska has freezing temperatures. Did you mean of instead of os?
How does cider cone volcano and shield volcano differ?
Cinder cones are small and steep-sloped, composed of volcanic cinders, and have mildly explosive eruptions. Shield volcanoes are large and shallow-sloped with very runny lava and generally non-explosive eruptions.
What kind of you eruptions do composite volcanoes make?
Composite volcanoes can contain a wide variaty of magmas ranging from basaltic to rhyolitic.
