Oceanic crust is generally younger than continental crust, being less than 200 million years old. It is made of basaltic rock, which is denser and more mafic than the granitic rock found in continental crust. Oceanic crust is thinner and more dense than continental crust, with average thickness of about 6 kilometers compared to about 35 kilometers for continental crust. Oceanic crust is also less buoyant and more prone to subduction.
Continental crust is generally thicker and less dense than oceanic crust, and is composed mainly of granitic rock. It is much older than oceanic crust, having formed over billions of years, and is also more buoyant due to its lower density. Continental crust is less prone to subduction and therefore is more likely to form mountains and landforms. It is also much thicker, with an average thickness of about 35 kilometers.