What magma causes powerful and explosive volcanic eruptions?
Explosive eruptions are favored by high gas content & high viscosity magmas (andesitic to rhyolitic magmas).
Which of these magmas produce the most explosive eruptions?
The largest and most violent of all the types of volcanic eruptions are Plinian eruptions. They are caused by the fragmentation of gassy magma and are usually associated with very viscous magmas (dacite and rhyolite).
Which type of magma will produce the least explosive volcanic eruption quizlet?
A magma with low silica (<45%) will be runny and so the eruption will not be explosive.
What causes a volcanic eruption?
The melted rock, or magma, is lighter than the surrounding rock and rises up. This magma collects in magma chambers, but it is still miles below the surface. When enough magma builds up in the magma chamber, it forces its way up to the surface and erupts, often causing volcanic eruptions.
What volcanoes have explosive eruptions?
Hawaiian volcanoes have produced explosive eruptions ranging in size and vigor from relatively small lava fountains to large eruptions.
What are the 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 type of lava is the most explosive?
A Plinian eruption is the most explosive of the eruption types.
Which magma composition should lead to the most explosive volcanoes and why quizlet?
More viscous magmas tend to generate more explosive eruptions. List these three magmas in order from most silica rich to least silica rich, based on their compositions: mafic (basaltic), felsic (rhyolitic), intermediate (andesitic). The eruption of what type of magma may produce an eruption column?
Which magma type erupts most violently quizlet?
Rhyolitic– Highest Viscosity (thickest), causes the most violent explosive eruptions.
What are the three major types of magma?
It also contains small amounts of dissolved gases such as water vapor, carbon dioxide, and sulfur. The high temperatures and pressure under Earth's crust keep magma in its fluid state. There are three basic types of magma: basaltic, andesitic, and rhyolitic, each of which has a different mineral composition.
What causes a volcanic eruption Wikipedia?
A volcanic eruption occurs when hot materials from the Earth's interior are thrown out of a volcano. Lava, rocks, dust, and gas compounds are some of these "ejecta".
What type of magma is explosive?
Explosive eruptions are favored by high gas content and high viscosity (andesitic to rhyolitic magmas).
What causes volcanic eruption?
The melted rock, or magma, is lighter than the surrounding rock and rises up. This magma collects in magma chambers, but it is still miles below the surface. When enough magma builds up in the magma chamber, it forces its way up to the surface and erupts, often causing volcanic eruptions.
What are the causes of volcanic eruption?
Although there are several factors triggering a volcanic eruption, three predominate: the buoyancy of the magma, the pressure from the exsolved gases in the magma and the injection of a new batch of magma into an already filled magma chamber.
What type of eruption is the most explosive?
Plinian eruption A Plinian eruption is the most explosive of the eruption types.
What are 3 types of magma?
It also contains small amounts of dissolved gases such as water vapor, carbon dioxide, and sulfur. The high temperatures and pressure under Earth's crust keep magma in its fluid state. There are three basic types of magma: basaltic, andesitic, and rhyolitic, each of which has a different mineral composition.
What causes volcanic eruptions?
The melted rock, or magma, is lighter than the surrounding rock and rises up. This magma collects in magma chambers, but it is still miles below the surface. When enough magma builds up in the magma chamber, it forces its way up to the surface and erupts, often causing volcanic eruptions.
Which type of magma would you expect to produce the most explosive volcanic eruption quizlet?
More viscous magmas tend to generate more explosive eruptions. List these three magmas in order from most silica rich to least silica rich, based on their compositions: mafic (basaltic), felsic (rhyolitic), intermediate (andesitic).
What causes the most explosive volcanic eruption quizlet?
Silica-rich magma is stiff, and hardens in a volcano's vent and plugs the vent. As more magma pushes up, pressure increases, causing an explosive eruption.
Which is the most explosive type of volcanic eruption quizlet?
*NOTE: The Composite Volcano (Stratovolcano) is the most explosive.
What is the molten magma?
Magma is a molten and semi-molten rock mixture found under the surface of the Earth. This mixture is usually made up of four parts: a hot liquid base, called the melt; minerals crystallized by the melt; solid rocks incorporated into the melt from the surrounding confines; and dissolved gases.
What is cause of volcanic eruption?
The melted rock, or magma, is lighter than the surrounding rock and rises up. This magma collects in magma chambers, but it is still miles below the surface. When enough magma builds up in the magma chamber, it forces its way up to the surface and erupts, often causing volcanic eruptions.
What type of lava is explosive?
Effusive eruptions occur when hot, (1200oC) runny basalt magmas reach the surface. Dissolved gases escape easily as the magma erupts, forming lava that flows downhill quite easily.
Which type of lava is most explosive?
A Plinian eruption is the most explosive of the eruption types.
What is mafic magma?
Describes magma that contains lower amounts of silica and is generally less viscous and less gas-rich than silicic magma. Tends to erupt effusively, as lava flows. Includes andesites (57-63 percent SiO2), basaltic andesites (53-57 percent SiO2), and basalts (47-53 percent SiO2).
What are the 3 types of magma?
It also contains small amounts of dissolved gases such as water vapor, carbon dioxide, and sulfur. The high temperatures and pressure under Earth's crust keep magma in its fluid state. There are three basic types of magma: basaltic, andesitic, and rhyolitic, each of which has a different mineral composition.
What causes volcanic explosions quizlet?
Magma underground is under intense pressure, so water in magma stays dissolved. If the magma moves quickly to the surface, the pressure suddenly decreases and the water and other compounds become gases. As the gases expand rapidly, an explosion can result.
Which property of magma is important for determining how explosive an eruption will be?
CONTROLS ON EXPLOSIVITY The viscosity of the magma, however, is also an important factor in determining whether an eruption will be explosive or nonexplosive. A low-viscosity magma, like basalt, will allow the escaping gases to migrate rapidly through the magma and escape to the surface.
What type of volcano is explosive?
Stratovolcanoes are more likely to produce explosive eruptions due to gas building up in the viscous magma. Andesite (named after the Andes Mountains), is perhaps the most common rock type of stratovolcanoes, but stratovolcanoes also erupt a wide range of different rocks in different tectonic settings.
What is called magma?
Magma is a molten and semi-molten rock mixture found under the surface of the Earth. This mixture is usually made up of four parts: a hot liquid base, called the melt; minerals crystallized by the melt; solid rocks incorporated into the melt from the surrounding confines; and dissolved gases.