2. 1. Crust- outermost layer of Earth’s interior that consists of solid rock.

3.  Continental crust is thicker and less dense than oceanic crust.  Continental crust is mostly granite and oceanic crust is mostly basalt.  Density:  Continental Crust: 2.7 g/cm 3  Oceanic Crust: 3.0 g/cm 3

4. 2. Mantle – the layer below the crust that is also mostly solid rock  Parts of the mantle are liquid and capable of flowing like a plastic.  Makes up 80% of Earth’s volume

5. 3. Core – inner part of Earth’s interior that is made of iron and nickel.  The core is subdivided into two layers the outer core and the inner core.  The inner core is solid and the outer core is liquid

6.  The boundary between the mantle and the crust is known as the mohorovisic discontinuity, or moho.  This boundary is based on sudden change in density.

7.  Earth’s interior can also be divided in a way useful to further understanding 1. Lithosphere – solid rock consisting of the crust and the uppermost part of the mantle.

8. 2. Asthenosphere – found below the rigid mantle and is mostly solid but slowly moving  Similar to silly putty

9.  Most of what we know about Earth’s interior comes from the behavior of seismic waves which are generated by earthquakes.