Why is the amount of silica in magma important




















This provides the flux needed to lower the melting temperature. The magma produced, being less dense than the surrounding rock, moves up through the mantle, and eventually into the crust.

As it moves toward the surface, and especially when it moves from the mantle into the lower crust, the hot magma interacts with the surrounding rock. This typically leads to partial melting of the surrounding rock because most such magmas are hotter than the melting temperature of crustal rock. In this case, melting is caused by an increase in temperature. Again, the more silica-rich parts of the surrounding rock are preferentially melted, and this contributes to an increase in the silica content of the magma.

As the temperature drops, usually because the magma is slowly moving upward, things start to change. Silicon and oxygen combine to form silica tetrahedra, and then, as cooling continues, the tetrahedra start to link together to make chains polymerize.

As the magma continues to cool, crystals start to form. This is an experiment that you can do at home to help you understand the properties of magma. It will only take about 15 minutes, and all you need is half a cup of water and a few tablespoons of flour.

Add 2 teaspoons 10 mL of white flour this represents silica and stir while the mixture comes close to boiling. It should thicken like gravy because the gluten in the flour becomes polymerized into chains during this process.

Take another 4 teaspoons 20 mL of flour and mix it thoroughly with about 4 teaspoons 20 mL of water in a cup and then add all of that mixture to the rest of the water and flour in the saucepan. Stir while bringing it back up to nearly boiling temperature, and then allow it to cool.

This mixture should slowly become much thicker — something like porridge — because there is more gluten and more chains have been formed see the photo. This is analogous to magma, of course.

See Appendix 3 for Exercise 3. Figure 3. Oxygen However, its melting point is dependent on the temperature and pressure the rock is under. Dry mantle rock under extreme pressure requires a much higher temperature to melt than dry mantle rock under less pressure. When liquid is added to dry mantel rock at a pressure and temperature point in which wet mantle rock would be melted, flux melting occurs.

Waves form on the ocean and on lakes because energy from the wind is transferred to the water. The stronger the wind, the longer it blows, and the larger the area of water over which it blows the fetch , the larger the waves are likely to be.

The important parameters of a wave are the wavelength the horizontal distance between two crests or two troughs , the amplitude the vertical distance between a trough and a crest , and the wave velocity the speed at which wave crests move across the water Figure The typical sizes and speeds of waves in situations where they have had long enough to develop fully are summarized in Table In other words, not only are large waves bigger than small ones, they are also generally more than twice as steep, and therefore many times more impressive—and potentially dangerous.

It is important to recognize, however, that amplitudes decrease with distance from the area where the waves were generated. Waves on our coast that are generated by a storm near Japan will have similar wavelengths but lower amplitudes than those generated by a comparable storm just offshore. This table shows the typical amplitudes and wavelengths of waves generated under different wind conditions. See Appendix 3 for Exercise As a wave moves across the surface of the water, the water itself mostly just moves up and down and only moves a small amount in the direction of wave motion.

As this happens, a point on the water surface describes a circle with a diameter that is equal to the wave amplitude Figure This motion is also transmitted to the water underneath, and the water is disturbed by a wave to a depth of approximately one-half of the wavelength. If you look carefully at that animation, and focus on the small white dots in the water, you should be able to see how the amount that they move decreases with depth.

Explosive bursting of bubbles will fragment the magma into clots of liquid that will cool as they fall through the air. Volcanic Smog vog is produced from SO2 gas and is a hazard in Hawaii. Granite, the equivalent of its extrusive volcanic rock type rhyolite, is a very common type of intrusive igneous rock.

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.

Silica is an important trace mineral that provides strength and flexibility to the connective tissues of your body — cartilage, tendons, skin, bone, teeth, hair, and blood vessels. Silica is essential in the formation of collagen, the most abundant protein found in your body. While research has turned up no clear benefit to supplements, consuming too much of certain vitamins can be harmful.

Too much calcium and vitamin D are associated with an increased risk of cardiovascular disease, Miller says. China is the most polluted nation on the planet by far , yet many fruits, vegetables and herbs are grown in China and exported to North America for use in our natural products.

Silica affects magma because it makes the magma thicker. Silica is the MAIN ingredient of magma. It is made up of oxygen and silicon.

I hope this helps:. High silica magma is more viscous sticky than low silica magma, so low silica magma lows easier. The higher the silica content, the higher the viscosity of magma and lava. Silicate magma is magma with high levels of silica in it.

Silica is found in the Earth's crust and often mixes with magma. High silica magma is light in color, thick, sticky and less dense than basalt magma. The magma that forma volcanoes is rich in silica. High silica magma have low temperatures because magma that is high in silica have the lowest temperatures.

Silica rich magma builds a tall cone shaped volcano, a Stratovolcano. Magma that is high in silica resists flowing, so expanding gases are trapped in it. Pressure builds up until the gases blast out in a violent, dangerous explosion. Log in. See Answer. Best Answer.

Study guides. Q: Why is the amount of Silica in magma important? Write your answer Related questions. Which magma has silica in it? Is andesitic magma silica rich?

How does the amount of silica affect how magma flows? What factors determine the viscosity of magma? What is the difference between basaltic magma and silicic magma? What is silica in magma? What does the amount of silica in a volcano's magma determine about its eruption? Which type of magma contains the most amount of silica?



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