The continents and ocean floor are part of Earth's _________ ?

Our Earth can be divided into three layers. The outermost layer of Earth is known as the crust. Continents and ocean floors are part of the crust. In fact, we divide the crust in terms of continental crust and oceanic crust, depending upon whether the continents exist on a particular portion of crust or not. Underlying the crust is the part of Earth known as the mantle and further underneath that is the core of Earth.

The crust is a thin layer of the Earth and its thickness varies from 20-30 miles in the case of continental crust and 3-6 miles in the case of oceanic crust. The crust is divided into a number of fragments known as tectonic plates. These tectonic plates are in constant motion and that is why continents are also always moving (although at an extremely slow pace). 

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