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How are igneous rocks formed? hints how are igneous rocks formed? igneous rocks are formed only from material ejected during a volcanic eruption. igneous rocks are formed by the cooling and crystallization of molten rock. igneous rocks are produced by the weathering and transport of pre-existing rocks. igneous rocks are formed by the cooling of magma above earth's surface and lava below the surface. igneous rocks are formed by recrystallization due to i?

User Jinbo Wang
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Answer:

Igneous rock is formed by the melting and cooling of magma or lava.

Inside of Earth, magma slowly cools, creating rock with an irregular or rough texture and large crystals. Magma cooling inside Earth creates intrusive igneous rock. Outside of Earth, lava cools very quickly, creating rock with a fine, grainy look or texture and small crystals. Lava cooling outside of Earth creates extrusive igneous rock.

Examples: granite, basalt, and pumice

Step-by-step explanation:

Hope this is a help to you and others! :)

User Woody
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Igneous rock are formed by the cooling and crystallization of molten rock and are formed by the cooling of magma above earth's surface.

Let's look into the statements one by one:

Igneous rocks are formed only from material ejected during a volcanic eruption.

-This is not true because igneous rock can also be formed by the cooling down of magma inside a volcano or magma that was trapped in the crack of crust.

Igneous rocks are formed by the cooling and crystallization of molten rock.

-This is correct.

Igneous rocks are produced by the weathering and transport of pre-existing rocks.

-This is incorrect as igneous rock is formed by volcanism. The rock that are formed with the statement is sedimentary rock.

Igneous rocks are formed by the cooling of magma above earth's surface and lava below the surface.

-This is correct. Both intrusive and extrusive volcanic activity forms igneous rock after cooling down.

Igneous rocks are formed by recrystallization

-This is not true as recrystallization does not take place in the formation of the igneous rock. The rock formed by recrytillization is metamorphic rock.

Therefore,the igneous rock are formed by the cooling and crystallization of molten rock and are formed by the cooling of magma above earth's surface.

Hope it helps!

User Halena
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