Continental Crust
The land on Earth is made from the continental crust and is comprised of mostly rock, specifically a rock called granite. The continental crust is anywhere from 8 kilometers to 70 kilometers thick, varying in thickness depending on elevation (National Geographic Kids, 2015). In contrast to the oceanic crust of Earth the continental crust is old and thick, as described by Alden (2015a). The crust is referred as old because they estimate the age of the continental crust to be roughly 2 billion years old and an estimated 50 kilometers thick. Because most of the continental crust lies above sea level this has allowed for the existence of life form to develop. The continental crust is the last and final portion of the crust layer that surrounds the Earth.
Though scientists are still exploring our complex planet Earth, we know there are many layers that make up the planet that we live on. With advancing technology we are getting closer and closer to discovering more about the Earth and its layers. There are ongoing studies to plunge deeper into the Earth past the few layers of the crust to discover more. Although there is still much to learn there is still much to discover. Simply put, these are the three layers that compose the third planet from the sun, Earth; the crust, mantle and core.