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How are extrusive and intrusive rocks formed ? Explain.​

User Semao
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Answer:

Extrusive rocks are formed on the surface of the Earth from lava, which is magma that has emerged from underground. Intrusive rocks are formed from magma that cools and solidifies within the crust of the planet. ... If lava cools almost instantly, the rocks that form are glassy with no individual crystals, like obsidian.

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User Osman Mamun
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Extrusive rocks are formed on the surface of the Earth from lava, which is magma that has emerged from underground. Intrusive rocks are formed from magma that cools and solidifies within the crust of the planet. ... If lava cools almost instantly, the rocks that form are glassy with no individual crystals, like obsidian.
User Artem Klevtsov
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