Highly viscous felsic magma causes the most violent volcanic eruptions.
This is because silica-rich magma is thicker. The thicker the magma, the chance for the dissolved gas in there to escape is less likely. This causes an explosion. When the gases do escape, they cause an even bigger explosion
If the rocks below the volcano melt, the liquid rock will gather in a chamber underground. As the pressure in this chamber increases the magma may be forced out. This is an eruption. Eruptions are more likely to be explosive if the magma contains a large amount of water or gas, as the expansion of the water or gas makes the magma explode as it is released.
Granitic rocks are intrusive, which means they crystallized underground. Basaltic rocks are extrusive, meaning they crystallized above ground. Also, basaltic rocks are more mafic, and granitic rocks are more felsic.
Low viscosity mafic magma.
No, quiet eruptions.
Not usually. Explosive eruptions are more often to magma with high or moderate silica levels.
Magma that tends to cause explosive eruptions is typically high in silica content, making it thick and viscous. This results in gas build-up and pressure within the magma chamber, leading to explosive eruptions.
The source of materials for volcanoes that erupt in both explosive and effusive ways is primarily the mantle beneath the Earth's crust. Magma is generated from the partial melting of the mantle rock, which can lead to either explosive eruptions (due to trapped gases) or effusive eruptions (due to low gas content). This is known through the study of volcanic rocks, gases emitted during eruptions, and monitoring of volcanic activity.
yes
Magma with high silica content (felsic magma) tends to produce explosive eruptions because it is more viscous and traps gases, leading to pressure build-up before they are released explosively. This type of magma commonly forms in subduction zones where oceanic plates are being subducted beneath continental plates.
Gas, primarily water vapor.
Yes. The gas is actually the primary driving force behind explosive eruptions.
Yes. The gas is actually the primary driving force behind explosive eruptions.
Silica-rich magma has high viscosity, which can trap gas bubbles. When pressure builds up, the gas can cause explosive eruptions as it tries to escape through the thick magma. The high silica content also promotes the formation of explosive pyroclastic materials during an eruption.
Kilauea is a shield volcano fed by gas-poor basaltic magma. It is the gas in the magma that makes eruptions explosive. Kilauea has occasionally produced explosive eruptions when magma cam in contact with water.
Viscosity of magma affects the explosiveness of volcanic eruptions. Magma with high viscosity traps gas bubbles, increasing pressure, leading to more explosive eruptions. In contrast, low viscosity magma allows gas to escape easily, resulting in less explosive eruptions.