The Earth’s Interior

Most of what we know is from geophysics

Evidence from Seismic Waves Seismic Reflection Seismic Refraction

Earth’s Internal Structure The Core P-wave Shadow Zone S-wave Shadow Zones Liquid Outer Core Solid Inner Core

S-Wave Shadow Zone

Earth’s Internal Structure The Earth’s Crust Continental crust- sial Less dense and thicker than oceanic crust Oceanic crust- sima Mohorovicic discontinuity

P-Wave Velocities & Boundaries Moho

Earth’s Internal Structure The Mantle Ultramafic Rock Lithosphere Crust & uppermost mantle Asthenosphere Low velocity zone Lower mantle

Earth’s Internal Structure Composition of the Core Made of metal The Core-Mantle Boundary Convection in both core and mantle