in quiet eruptions, the magma or lava contains more silica than explosive eruptions. in explosive eruptions magma has less silica because lava becomes less dense and can shoot out of an volcano
The textbook answer would be that a composite volcano is composed of high-silica material. In reality composite volcanoes are highly variable. Mount St Helens, a composite volcano, has erupted material ranging from low-silica basalt to high-silica dacite.
The textbook answer would be that composite volcanoes erupt high-silica material. In reality they are highly variable, sometimes erupting different types of material at different times. Mount St. Helens, for example, has primarily erupted high-silica dacite in modern times, but layers of moderate-silica andesite and low-silica basalt have been found.
In general, the silica content of lava in less explosive more "quiet" eruptions will be low, with a higher temperature and lower gas content as all these parameters act to reduce the viscosity of the lava making it flow more easily and so less likely to form a viscous "plug" that can result in an explosive eruption as well as reducing the tendency for rapid exsolution of gas which can also make an eruption more explosive.
The reciprocal of this is also true, whereby If the temperature of the lava is decreased or the silica content increases then the viscosity of the lava will increase making an explosive / noisy eruption more likely to occur.
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Quiet volcanoes usually have a low viscosity, low silica magma.
sence it has very low viscosity it would have low silica, i think....not for sure.
I am sorry to disappoint you... But there are currently no reasonable answers for this question. Go ask a real scientist!
Very low amount of silica.
low silica
Andesite
They feature magma with very high silica content.
Not usually. Explosive eruptions are more often to magma with high or moderate silica levels.
Occasionally, yes. Most of Kilauea's eruptions are effusive, however.
The more silaceous the lava, (higher silica content), the more explosive the eruption.
Andesite
They feature magma with very high silica content.
Not usually. Explosive eruptions are more often to magma with high or moderate silica levels.
The more silaceous the lava, (higher silica content), the more explosive the eruption.
Occasionally, yes. Most of Kilauea's eruptions are effusive, however.
silica rich magma associated with explosive eruptions because it tends to trap water and gas bubbles :)
An explosive eruption is caused by magma with a high content of water and silica. Non-explosive eruptions are caused by either lava because it is a thicker consistency, or magma with a low content of water and silica.
Magma with high silica, high viscosity, and higher gas content.
yes
Because Mount Rainier is a Strato Volcano it has both quiet and explosive eruptions. Explosive(pyroclastic) flows have a high silica level. Quiet have low silica levels. The more silica the thicker the magma.
Many have rhyolitic magma, which is high in silica. Magma with higher viscosity and higher gas content is the most explosive when released.
Yes it is high in silica because composite volcanoes are known for being explosive. Composite volcanoes, sometimes referred to as stratovolcanoes, one of Earth's most common type.They form by explosive eruptions of pyroclastic material followed by quieter outpourings of lava. This usually indicates high silica content. High silica makes for thicker magma that can clog up the vent from the volcanoe's last eruption. Which makes the next eruption far more explosive because the magma has to free its self out of the vent, and with tremendous force it succeeds sky rocketing billions of pieces of pyroclastic material out of its vent. (this is known as an explosive eruption.)