The outermost layer of rock on the earth is called
the crust, which includes the continental crust
and oceanic crust. Why is the oceanic crust
much thinner than the continental crust,
but much more dense?
A it's composed of silica which
is high in oxygen and silicon
B it's composed of basalt which
is high in iron and magnesium
C it's under the ocean
D it's younger
