Question #a29c9

1 Answer
Jan 23, 2018

No.
But, every rock on Earth has been formed from the cooling of semi-solid mantle at the crust.

Explanation:

Plate tectonics show us there are major continental and ocean plates with usually, pretty clear boundaries.
It is at the constructive plate boundaries between oceanic plates that a lot of 'new' rock is formed on the planet, this is however the place where new oceanic crust/rock is formed at the mid ocean ridges, however, at the destructive/convergent plate boundaries that oceanic crust is melted back into semi-solid magma below the continental plates.

We also have to remember that a lot of the rock on our planet is constantly recycled, being melted back down, eroded, compacted, heated, dissolved, moved.

Hope this helps.

-Charlie