12CrustThe plates move along smoothly but sometimes they get stuck and pressure builds up.
13The pressure builds and causes an Earthquake as rocks break and crack. CrustSan Francisco City Hall after the 1906 Earthquake. (from Steinbrugge Collection of the UC Berkeley Earthquake Engineering Research Center)The pressure builds and causes an Earthquake as rocks break and crack.
14Mantle The mantle is the largest layer of the Earth. It is made of hot, dense rock. The rock in the mantle flows like asphalt because of the temperature differences found in the mantle.
15MantleThe movement of the mantle create the movement of the Earth’s plates.
16CoreThe core of the Earth is much like a ball of very hot metals. The inner core is surrounded by a fluid iron outer core.