Magma & Lava
Magma is a combination of molten rock forming substance, gases, and water from deep within Earth's mantle. In the asthenosphere, magma forms while held down by tremendous pressure. Lighter than the surrounding rock, it rises up to the surface through cracks or gets stuck under rock layers. Lava is the term for magma once it has reached the surface. There are many different characteristics of magma and lava that determine outcomes such as the type of eruption of a volcano. New magma can also be created by subduction at convergent boundaries as a plate returns to the mantle.
Magma can be fluid and glide like water or be thick and move leisurely. These characteristics are influenced by the temperature of the magma and silica content. The strength of the eruption depends on the magma's dissolved gas, silica, temperature, and consistency. The lava and magma is more fluid if it is hotter.
Lava Flow
Lava flow is the area covered by lava after it erupts from the volcano or as it gushes from the vent. The consistency of the lava can determine how far the lava gets and how much damage it may cause.
Silica
Silica, a combination of oxygen and silicon elements, can affect both the consistency of magma and the intensity of the eruption. It is one of the most bountiful materials in Earth's crust and mantle. Thick, light-colored, and sticky magma is formed when the content of silica is very high. The more silica, the thicker the magma is. With thick magma, an explosive eruption is concocted and the lava becomes too sticky to flow far. Rhyolite, pumice, and obsidian are all rocks that are created when lava with high silica levels cool down. Rhyolite is similar to granite and is formed when the lava hardens. Obsidian is a glossy rock with a polished surface, fashioned when lava with a lot of silica cools. Pumice is an light rock with pockets of air, created when this lava cools while bubbles of gas are trapped in the cooled material.
Magma with low silica content produces quiet eruptions. This type of magma makes dark-colored, easily flowing lava. The result from this lava is rocks like basalt.
Gas
The gas in magma is very important to the eruption of a volcano. Along with silica, it can determine the intensity of the explosion. The volcanic gas dissolved in the magma is partially what helps create explosive eruptions. As read above, when the silica content is high, the magma is thick. If the magma is plugs the pipe, the dissolved gases want to escape desperately, but can't. The pressure then increases in the pipe and vent until the the volcano's gases erupt -- explosively. During a quiet eruption, the gas dissolved in the magma is released without a problem. The intensity of the eruption can also depend on how much gas is dissolved in the magma.
Since magma is under such great pressure in the mantle, as it rises the pressure decreases. The gases that have been dissolved in the magma begin to spread out into bubbles. Once the magma becomes lava, the gas is released.
Magma is a combination of molten rock forming substance, gases, and water from deep within Earth's mantle. In the asthenosphere, magma forms while held down by tremendous pressure. Lighter than the surrounding rock, it rises up to the surface through cracks or gets stuck under rock layers. Lava is the term for magma once it has reached the surface. There are many different characteristics of magma and lava that determine outcomes such as the type of eruption of a volcano. New magma can also be created by subduction at convergent boundaries as a plate returns to the mantle.
Magma can be fluid and glide like water or be thick and move leisurely. These characteristics are influenced by the temperature of the magma and silica content. The strength of the eruption depends on the magma's dissolved gas, silica, temperature, and consistency. The lava and magma is more fluid if it is hotter.
Lava Flow
Lava flow is the area covered by lava after it erupts from the volcano or as it gushes from the vent. The consistency of the lava can determine how far the lava gets and how much damage it may cause.
Silica
Silica, a combination of oxygen and silicon elements, can affect both the consistency of magma and the intensity of the eruption. It is one of the most bountiful materials in Earth's crust and mantle. Thick, light-colored, and sticky magma is formed when the content of silica is very high. The more silica, the thicker the magma is. With thick magma, an explosive eruption is concocted and the lava becomes too sticky to flow far. Rhyolite, pumice, and obsidian are all rocks that are created when lava with high silica levels cool down. Rhyolite is similar to granite and is formed when the lava hardens. Obsidian is a glossy rock with a polished surface, fashioned when lava with a lot of silica cools. Pumice is an light rock with pockets of air, created when this lava cools while bubbles of gas are trapped in the cooled material.
Magma with low silica content produces quiet eruptions. This type of magma makes dark-colored, easily flowing lava. The result from this lava is rocks like basalt.
Gas
The gas in magma is very important to the eruption of a volcano. Along with silica, it can determine the intensity of the explosion. The volcanic gas dissolved in the magma is partially what helps create explosive eruptions. As read above, when the silica content is high, the magma is thick. If the magma is plugs the pipe, the dissolved gases want to escape desperately, but can't. The pressure then increases in the pipe and vent until the the volcano's gases erupt -- explosively. During a quiet eruption, the gas dissolved in the magma is released without a problem. The intensity of the eruption can also depend on how much gas is dissolved in the magma.
Since magma is under such great pressure in the mantle, as it rises the pressure decreases. The gases that have been dissolved in the magma begin to spread out into bubbles. Once the magma becomes lava, the gas is released.