A volcano’s explosiveness depends on the composition of the magma (molten rock) and how readily gas can escape from it. As magma rises and pressure is released, gas bubbles (mainly of water vapor and carbon dioxide) form and expand rapidly, causing explosions.
Which type of volcano is the most powerful and explosive?
What two substances in magma causes explosive eruptions?
The key to whether an eruption will be explosive lies in the silica, water, and gas content of the magma. C. Water and Magma Are an Explosive Combination If the water content of magma is high, an explosive eruption is more likely.
What is magma or lava?
Scientists use the term magma for molten rock that is underground and lava for molten rock that breaks through the Earth’s surface.
What happens if a volcano’s magma is high in silica?
Volcanic Eruptions: High Silica Lava with high silica content is thick and viscous and does not readily flow. Lava rises up toward the surface but is too thick to squeeze through the cracks and fissures in the Earth. As lava continues to rise upward, pressure continues to build.
Is Lava more explosive than magma?
They’re also cooler than mafic magmas. Rhyolite, an especially silica-rich type of lava, hits temperatures between only 1,200 degrees to 1,500 degrees Fahrenheit. This makes silicic magmas more dangerous: As more gas builds up in the magma, it becomes more explosive, like adding more and more carbonation to a soda.
What is the shortest volcano?
Is Taal volcano going to erupt again?
Taal volcano (Philippines): fears of possible new eruption trigger evacuation of residents. Ongoing elevated seismic activity under the volcano sparked fears that the volcano, which had a massive, devastating eruption little more than a year ago, in January 2020, might erupt again in the near future.