Magma is not explosive. It is however under pressure like water in hose.
If you increase the water pressure in hose it will eventually rupture, sometimes violently. Magma contained in the volcano acts the same way. There are often gases associated with magma and lava that may spew the ash and magma a considerable distance, this is not an explosion.
Magma sometimes flows over a pond of water or falls into the sea. The violent creation of steam looks explosive but again, it is just rapid expansion.
Lava can be classified into two main types: mafic lava, which is rich in magnesium and iron and tends to flow easily, creating broad shield volcanoes, and felsic lava, which is high in silica and more viscous, leading to explosive eruptions and the formation of stratovolcanoes.
Like many stratovolcanoes, Mount St Helens has produced material of mafic, felsic, and intermediate composition. Overall, much of the material is itermediate. The 1980 eruption and later activity have produced dacite, which has an intermediate-felsic composition
They can. Composite volcanoes vary in what they erupt. Many composite volcanoes are composed of a mixture of mafic, felsic, and intermediate rock. However, in most cases intermediated or felsic rock predominates.
A mafic lava flow will move faster than a felsic lava flow due to its lower viscosity. However, felsic magma tends to erupt explosively, producing fast-moving pyroclastic flows instead of lava flows.
Magma with high silica content (felsic magma) tends to produce explosive eruptions because it is more viscous and traps gases, leading to pressure build-up before they are released explosively. This type of magma commonly forms in subduction zones where oceanic plates are being subducted beneath continental plates.
Like many stratovolcanoes, Mount St Helens has produced material of mafic, felsic, and intermediate composition. Overall, much of the material is itermediate. The 1980 eruption and later activity have produced dacite, which has an intermediate-felsic composition
They can. Composite volcanoes vary in what they erupt. Many composite volcanoes are composed of a mixture of mafic, felsic, and intermediate rock. However, in most cases intermediated or felsic rock predominates.
Mafic lava is low in silica and high in iron and magnesium, which makes it less viscous and more fluid compared to felsic lava. It tends to flow easily and often forms basaltic rocks when it cools. Mafic lava eruptions typically result in gentle, effusive lava flows rather than explosive eruptions.
A mafic lava flow will move faster than a felsic lava flow due to its lower viscosity. However, felsic magma tends to erupt explosively, producing fast-moving pyroclastic flows instead of lava flows.
Magma with high silica content (felsic magma) tends to produce explosive eruptions because it is more viscous and traps gases, leading to pressure build-up before they are released explosively. This type of magma commonly forms in subduction zones where oceanic plates are being subducted beneath continental plates.
rhyolitic magma has a lot of silica and water vapors... thanks for asking answers.com ;)
Gas in lava can make it more explosive. When gas bubbles within the lava are trapped and then released during an eruption, it can lead to more violent explosions. The pressure from the gas causes the lava to fragment into smaller pieces, creating explosive eruptions.
Paricutin volcano in Mexico predominantly erupted mafic lava, which is rich in magnesium and iron and has a low silica content. This type of lava tends to flow more easily compared to felsic lava.
Oh, dude, Mt. Etna has both mafic and felsic lava. It's like a lava buffet up there! Mafic lava is low in silica and more runny, while felsic lava is high in silica and thicker. So, yeah, Mt. Etna serves up a mix of both, keeping things interesting for all the volcano enthusiasts out there.
Mt. Hood has lava with high silica content, resulting in a more viscous and explosive eruption compared to lavas with lower silica content. High silica lava tends to form more explosive eruptions due to its increased resistance to flow.
Mauna Loa exhibits non-explosive eruptions (like many in the Hawaiian islands) in the form of low viscosity (more fluid) lava due to poor silica content.
Eruptions involcing silicic or felsic magma are generally the worst. Eruptions of mafic material are usually effusive or only mildly explosive, producing cinders or lava flows. Eruptions of felsic material often produce large ash clouds and deadly pyroclastic flows.