What substance determines whether magma is chunky or flowy?

The higher the amount of silica in the magma, the higher is its viscosity. Viscosity is a liquid’s resistance to flow. Viscosity determines what the magma will do.

What substance determine the viscosity of magma?

Viscosity of Magmas

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).

What determines how thick or thin magma is?

Temperature, composition, and volatile (gas) content largely determine the viscosity of lava. Temperature: The hotter the lava, the lower the viscosity (the thinner it is). The cooler the lava, the higher the viscosity (the thicker it is).

What makes magma runny?

As magma approaches the surface, the pressure exerted on it decreases. Gas bubbles start to form, and the more gas there is in the magma, the more bubbles form. If the gas content is low or the magma is runny enough for gases to rise up through it and escape to surface, the pressure will not become excessive.

What factors determine magma composition?

Different minerals within a rock melt at different temperatures. The amount of partial melting and the composition of the original rock determine the composition of the magma. The words that describe composition of igneous rocks also describe magma composition.

Which of the following characteristic of magma determines its explosiveness?

The amount of dissolved gas in the magma provides the driving force for explosive eruptions. The viscosity of the magma, however, is also an important factor in determining whether an eruption will be explosive or nonexplosive.

What is the chemical composition of magma?

Magmas can vary widely in composition, but in general they are made up of only eight elements; in order of importance: oxygen, silicon, aluminum, iron, calcium, sodium, magnesium, and potassium (Figure 3.2. 1).

What are three ways that magma changes composition during cooling?

What are three ways that magma changes composition during cooling?

• Geothermal Gradient.
• Decompression Melting.
• Flux Melting.
• Heat-Induced Melting.
• References.

What are the three composition of magma?

Magma collects in magma chambers in the crust at 160 kilometers (100 miles) beneath the surface of a volcano. The words that describe composition of igneous rocks also describe magma composition. Mafic magmas are low in silica and contain more dark, magnesium and iron rich mafic minerals, such as olivine and pyroxene.

Which of the following determines how easily magma flows?

The two primary factors that determine how magma erupts is its viscosity and gas content.

What provides the force that causes magma to erupt the surface?

Magma contains dissolved gases, which provide the driving force that causes most volcanic eruptions. As magma rises towards the surface and pressure decreases, gases are released from the liquid portion of the magma (melt) and continue to travel upward and are eventually released into the atmosphere.

What makes magma different from lava?

Magma is composed of molten rock and is stored in the Earth’s crust. Lava is magma that reaches the surface of our planet through a volcano vent.

Which of the following materials from a volcano determines its explosiveness?

Which of the following materials from a volcano determines its explosiveness? The amount of dissolved gas in the magma provides the driving force for explosive eruptions. The viscosity of the magma, however, is also an important factor in determining whether an eruption will be explosive or nonexplosive.

Which characteristic of magma mainly determines?

Which characteristics of magma mainly determines its explosiveness? Viscosity, together with the amount of gas dissolved in magma, can determine the explosivity of the eruption. More viscous magma with volatiles is more explosive than less viscous magma, where gases can bubble out relatively easily.

What chemical and physical characteristics of magma are most important?

The chemical composition of the Magma determines whether the Magma will erupt explosively or mot. Explanation: There are a variety of gases that are present and very high pressure in the centre of the earth. Certain gases like oxides of nitrogen when present in high amount in the Magma makes it explosive.

Which ingredient in magma determines whether an eruption is explosive or quiet?

The viscosity, temperature and composition of the magma determine whether the explosion is explosive or effusive. 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.

Which ingredient in magma determines whether an eruption is explosive or quiet Quizizz?

Q. Which ingredient in magma determines whether an eruption is explosive or quiet? Amount of rock.

How does magma influences the explosiveness of an eruption?

More crystals in the magma enable more gas bubbles to form, and so they make an eruption more explosive. The rate at which pressure is reduced also affects the explosiveness. If magma moves slowly toward the surface, gases in the magma have more time to escape.

What determines how explosive an eruption is?

Volcanic eruptions can be explosive, sending ash, gas and lava high up into the atmosphere, or the magma can form lava flows, known as effusive eruptions. Whether an eruption is explosive or effusive largely depends upon the amount of gas in the magma.

How is magma formed?

Magma forms from partial melting of mantle rocks. As the rocks move upward (or have water added to them), they start to melt a little bit. These little blebs of melt migrate upward and coalesce into larger volumes that continue to move upward. They may collect in a magma chamber or they may just come straight up.