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Our transcription: Oceanic crust represents material, which has come to the Earth's surface directly by magmatism out of the Earth's mantle. As the most common type of magma to come out of the Earth's mantle, it comes out as a composition of basalt, which is a silica magnesium rich rock. The continents represent material that has been recycled numerous times by igneous activity, metamorphism, sedimentation, deformation, melted, mountain building, deposition into basins, and recycled recycled. It basically came from proto-oceanic crust, but it has undergone many different changes through these processes through time to make it distinct and compositionally much lighter, which is a composition more similar to granite.
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