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magma
[mag-muh]
noun
plural
magmas, magmataGeology.molten material beneath or within the earth's crust, from which igneous rock is formed.
any crude mixture of finely divided mineral or organic matter.
Chemistry, Pharmacology.a paste composed of solid and liquid matter.
magma
/ ˈmæɡmə, mæɡˈmætɪk /
noun
a paste or suspension consisting of a finely divided solid dispersed in a liquid
hot molten rock, usually formed in the earth's upper mantle, some of which finds its way into the crust and onto the earth's surface, where it solidifies to form igneous rock
magma
The molten rock material that originates under the Earth's crust and forms igneous rock when it has cooled. When magma cools and solidifies beneath the Earth's surface, it forms what are known as intrusive rocks. When it reaches the Earth's surface, it flows out as lava and forms extrusive (or volcanic) rocks.
Other Word Forms
- magmatic adjective
- magmatism noun
- ˈپ noun
Word History and Origins
Word History and Origins
Origin of magma1
Example Sentences
The size of Strombolian eruptions can vary but are often characterised by intermittent explosions, which occur due to the presence of gas in the magma chamber within the volcano.
“Mt. St. Helens, Mt. Rainier, Mt. Hood, Crater Lake — those kind of volcanoes have a lot more gas and are more explosive in general. The magma is more viscous,” Chadwick said.
“You just have to make sure you don’t get burned by the magma.”
So far, no-one has been able to work out if a volcano becomes more or less explosive when sea water in these vents mixes with magma.
Indeed, the fact that there were so many hot spots spaced so closely together suggests that there is a vast underground magma chamber system.
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When To Use
Magma is what molten (melted) rock is called when it’s under the earth’s surface. Lava is what molten rock is called when it flows out of a volcano or volcanic vent.To be clear, in popular use, magma and lava are essentially different names for the same liquid-hot, charred orange ooze—which name is used depends on whether it is above or below the surface.However, geologists and volcanologists have their reasons for using the two different terms to distinguish between forms of what is the same substance.Magma doesn’t always become lava—sometimes it cools and solidifies beneath the earth's surface. Sometimes, it collects in what’s known as a magma chamber. When it does reach the surface, it flows out as lava. The rock that’s formed when it hardens and cools can also be called lava, though this use of the term is uncommon outside of technical, scientific contexts.The word lava is perhaps the more well-known of the two because that’s the one we see when volcanoes erupt (or when the floor turns into it).Here is an example of magma and lava used correctly in the same sentence.Example: Lava began flowing from the volcano three days after scientists detected movement of magma underground.Want to learn more? Read the full breakdown of the difference between magma and lava.
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