Extrusive Rock
Igneous rock that forms when lava cools on Earth's surface.
Video: Extrusive Rock simple definition.
Imagine you're baking a cake, and it overflows from the pan, creating a mess on the oven floor. This is similar to how extrusive igneous rocks form when molten lava spills out onto the Earth's surface and cools quickly. Just as the cake batter solidifies into a new layer on the oven floor, the lava hardens into rock, forming a crusty surface layer; both processes involve a hot, flowing substance spreading out and solidifying into a new form.
Extrusive Rock Simple Definition:
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