The oceanic crust is composed of dark igneous rocks called ; whereas the upper continental crust has an average composition of a rock.

Basalt, sedimentary rock.

Explanation:

The reason why the continental crust differs from the oceanic crust is much different in its compositions. The continental crust is thin and less dense , is made of sedimentary and metamorphic rocks than the oceanic crust and is made of lighter elements. The tectonic plates move the composition to the rocks.

Answer carbon dioxide ice;