How Does Silica Content Affect The Viscosity Of Magma?






How Does Silica Content Affect The Viscosity Of Magma? Viscosity depends on primarily on the composition of the magma, and temperature. Higher SiO2 (silica) content magmas have higher viscosity than lower SiO2 content magmas (viscosity increases with increasing SiO2 concentration in the magma).

How does silica content affect the viscosity of lava? The cooler the lava, the higher the viscosity (the thicker it is). Composition: he more felsic the lava (the more silica in the lava), the higher the viscosity because silica forms chains in the cooling lava even before it crystallizes. The more mafic the lava (the less silica in it), the lower the viscosity.

How does silica content affect the viscosity of magma quizlet? A more viscous (thick) magma will produce a more violent eruption This is controlled in part by the concentration of silica in the magma. A magma with low silica (<45%) will be runny and so the eruption will not be explosive. A magma with high silica (>60%) will be quite viscous and so the eruption will be violent.

How is viscosity affected by silica content? Magmas with a higher SiO2 content have a higher viscosity. Ultimately, the viscosity of a magma will determine the shape a volcano takes over continued eruptions. A magma’s silica content will not only control the rock type that forms, it also controls the relative viscosity of the magma.

How Does Silica Content Affect The Viscosity Of Magma? – Related Questions

How does low silica content affect the viscosity of magma?

The amount of silica in magma helps to determine its viscosity. The more silica magma contains the higher its viscosity. Magma that is high in silica produces light-colored lava that is too sticky to flow very far ex. … Low-silica magma flows readily and produces dark-colored lava ex.

What factors affect the viscosity of magma?

A magma’s viscosity is largely controlled by its temperature, composition, and gas content (see downloadable programs at the bottom of this page). The effect of temperature on viscosity is intuitive. Like most liquids, the higher the temperature, the more fluid a substance becomes, thus lowering its viscosity.

How would you describe magma with high silica content?

Magmas with high silica content have a high viscosity (resistance to flow) and are generally more explosive when eruptions occur. All magmas also contain some degree of trapped gasses (CO2 & H2O ). The more trapped gas the more violent the explosion. All magma that reaches the surface can be classified as Lava.

How does the silica content affect the behavior of magma?

The silica content of the magma determines how thick the magma is, how easily it flows and how easily dissolved gases within the magma can escape; therefore the silica content determines the characteristic of the volcanic eruption and the shape and size of the resulting volcanic cone.

What affects the viscosity of magma quizlet?

VISCOSITY is directly related to the amount of silica (sand) in the magma. As silica content increases, viscosity increases. The magma slows down.

What is the relationship between silica content and magma viscosity multiple choice question?

Viscosity increases with more silica.

How does temperature and silica content affect the viscosity of magma?

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.

Does silica have high viscosity?

The chemistry of the lava controls viscosity. Lavas with more silica (SiO2) have higher viscosity because silica forms lots of chemical bonds, making the lava very stiff and very “sticky.”

Which of the following increases the viscosity of magma?

The viscosity of magma increases with: high % silica and cooler temperatures.

What are the factors affecting the viscosity of magma Brainly?

Lower temperature magmas have higher viscosity than higher temperature magmas (viscosity decreases with increasing temperature of the magma).

Which of the following would decrease the viscosity of magma?

Which of the following would decrease the viscosity of magma? The more the silica in magma, the lower the viscosity.

What are the factors that affect viscosity?

Increase in temperature decreases viscosity. Increases in pressure increase viscosity in liquids. In water, it decreases whereas, in gases, it remains the same.
Increase in temperature decreases viscosity.
Increases in pressure increase viscosity in liquids. In water, it decreases whereas, in gases, it remains the same.

What are the three factors that affect the viscosity of a lava?

The three factors that influence the viscosity of a lava are temperature, the dissolved gases it contains, and its chemical composition.

What is the viscosity of magma?

Magma viscosity varies, with temperature, water content, and composition, between about 102 Pa s and about 1011 Pa s.

What happens when the lava that flows during volcanic eruption has less silica content?

GAS: In a volcano with low silica content gas escapes easily from the surface of the lava. It can also escape through cracks and crevices on the surface. In volcanoes with high silica lava gas becomes trapped in the viscous lava and cannot escape.

What is the relationship between the silica content of magma and the explosiveness of a volcanic eruption?

Magmas with higher silica concentration are more viscous, and thus move slower than magmas with less silica. Where tectonic plates come together, volcanoes often have thicker, viscous magma with high gas content. This combination is explosive because the gases cannot easily boil out.

What is the connection between the amount of silica in amount and how viscous it is?

What is the connection between the amount of silica in a melt and how viscous it is? Silica forms strong bonds, so higher amounts of silica make for more viscous magma.

Why is silica rich magma explosive?

Magma Composition:

Such magmas erupt as andesites and rhyolites or are intruded as granite masses. The more extensive silicate chain molecules render these magmas highly viscous, so when eruption occurs it is usually explosive (e.g. Mt St Helens).

Which of the following best explains why silica SiO2 increases the viscosity of a magma?

Atoms vibrate more vigorously at higher temperatures, breaking bonds and increasing fluidity. Which of the following best explains why silica (SiO2) increases the viscosity of a magma? Silicon and oxygen bond to form silicon-oxygen tetrahedra, which bond to each other, making flow more difficult.

What does it mean by lower viscosity magma?

Low viscosity magmas allow gases to escape easily whereas gas pressures can build up in high viscosity magmas – resulting in violent eruptions. (Blowing through a straw, it’s easier to get water to bubble than a milk shake)

Why is it important to determine the viscosity of magma?

Among these factors, magma viscosity should be one of the most important, because the viscosity determines whether a dike (magma-filled crack) can be propagated with a high enough ascent velocity to overcome solidification [e.g., Rubin, 1995]. It is of importance that the magma viscosities can be calculated.

How can you increase the viscosity of magma?

How can viscosity change
In magmas, viscosity (14) is created by the number of bonds between SiO2 tetrahedrons (11) (O-O bond). .
One way to change the viscosity of a magma is too add water. .
The content in bubbles and crystals is also an important parameter that controls viscosity.
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