Is high temperature magma more viscous?
Viscosity of Magmas Lower temperature magmas have higher viscosity than higher temperature magmas (viscosity decreases with increasing temperature of the magma).
Which magma erupts at the highest temperature?
Since andesitic lava has a lower level of aluminum and silica in its composition it is normally hotter with a range of 750-950° C. The last type of lava is mafic lava or basaltic lava. This is one of the hottest types of lava coming out at temperatures exceed 950 degrees Celsius.
What are three types of magma?
There are three basic types of magma: basaltic, andesitic, and rhyolitic, each of which has a different mineral composition. All types of magma have a significant percentage of silicon dioxide. Basaltic magma is high in iron, magnesium, and calcium but low in potassium and sodium.
What are the 4 types of magma?
Because many of the properties of a magma (such as its viscosity and temperature) are observed to correlate with silica content, silicate magmas are divided into four chemical types based on silica content: felsic, intermediate, mafic, and ultramafic.
What is high silica magma?
Magmas that have a high silica content will therefore exhibit greater degrees of polymerization, and have higher viscosities, than those with low-silica contents. The amount of dissolved gases in the magma can also affect it’s viscosity, but in a more ambiguous way than temperature and silica content.
What will happen if magma extruded at high temperature?
When this magma reaches the surface, the gas bubbles will have a high pressure inside, which will cause them to burst explosively on reaching atmospheric pressure. This will cause an explosive volcanic eruption.
Which type of volcano the magma content is high?
MAGMA COMPOSITION AND ROCK TYPES
| SiO2 CONTENT | MAGMA TYPE | VOLCANIC ROCK |
|---|---|---|
| ~50% | Mafic | Basalt |
| ~60% | Intermediate | Andesite |
| ~65% | Felsic (low Si) | Dacite |
| ~70% | Felsic (high Si) | Rhyolite |
What magma type is the most vicious?
Not surprisingly, supervolcanoes are the most dangerous type of volcano. Supervolcanoes are a fairly new idea in volcanology. The exact cause of supervolcano eruptions is still debated, however, scientists think that a very large magma chamber erupts entirely in one catastrophic explosion.
How does temperature affect magma composition?
Viscosity of magma, the resistance to flow depends on composition of the magma and temperature. Higher silica content means higher viscosity. But lower temperatures and low gas content mean higher viscosity. Hence, lower viscosity and low gas content mean higher temperature of magma.
How does high silica affect magma?
What happens if a volcano is high in silica?
Silica: Influences lava viscosity and overall shape of the volcano. Silica molecules form a strong bond that permits entrapment of volcanic gases and promotes explosive volcanic eruptions. Low-silican magmas allow rapid escape of gases and low-explosivity eruptions.