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What natural phenomenon occurs when magma breaks through the earths crust?
Much of the planet’s mantle consists of magma. This magma can push through holes or cracks in the crust, causing a volcanic eruption. When magma flows or erupts onto Earth’s surface, it is called lava.
What happens when a magma bursts through the earth’s surface?
Lava cools to form volcanic rock as well as volcanic glass. Magma can also extrude into Earth’s atmosphere as part of a violent volcanic explosion. This magma solidifies in the air to form volcanic rock called tephra.
What causes volcanism?
How are volcanoes formed? Volcanoes are formed by eruptions of lava and ash when magma rises through cracks or weak-spots in the Earth’s crust. A build up of pressure in the earth is released, by things such as a plate movement which forces molten rock to exploded into the air causing a volcanic eruption.
What is the crack in Earth’s crust where magma pushes up through the crust?
1BVolcanoes
| Question | Answer |
|---|---|
| A crack in the earth’s crust through which molten rock comes to the surface. | volcano |
| A scientist who studies volcanoes. | volcanologist |
| Pockets of molten rock deep in the earth’s lithosphere. | magma chamber |
| Magma that has broken through the surface of the earth. | lava |
What happens to the magma after being pushed upward and exposed on the surface of the ocean floor?
When magma pressure builds up enough to force its way out to the seafloor, eruption occurs. Lavas pour from the fissure across the surface of the volcanic seafloor, adding a thin coat of new lava (typically <10 m thick) with each eruption. This process of magma ascending and lavas erupting is on-going and perpetual.
What is the main component of magma?
Oxygen
Oxygen, the most abundant element in magma, comprises a little less than half the total, followed by silicon at just over one-quarter. The remaining elements make up the other one-quarter. Magmas derived from crustal material are dominated by oxygen, silicon, aluminum, sodium, and potassium.