what physical layer of earth is broken into tectonic plates
The Earth's Crust, Lithosphere and Asthenosphere. Crust, the upper layer of the Earth, is not always the same. Crust under the oceans is only about 5 km thick while continental crust can be up to 65 km thick. Also, ocean crust is made of denser minerals than continental crust. The tectonic plates are made up of Earths crust and the upper part of the mantle layer underneath. Together the crust and upper mantle are called the lithosphere and they extend about 80 km deep. The lithosphere is broken into giant plates that fit around the globe like puzzle pieces.