What Are The Earth’s Layers ? • Inner Core • Outer Core • Mantle • Crust
Characteristics of The Inner Core • Solid ball due to high pressure (most dense layer) • 1540 miles across • 3700°C = VERY HOT! • Iron and nickel • Intense pressure keeps it • from liquefying
Characteristic of The Outer Core • Dense liquid molten rock • 1400 miles thick • Mainly iron and nickel • Some silicon • Between mantle and inner core • Gives Earth its magnetic field
Characteristics of The Mantle Parts are semi-molten (silly putty) 1800 miles thick Mantle rock is more dense than crustal rock Flows in sluggish currents Between crust and outer core
The Crust Earth’s outer rocky surface 4 miles thick under oceans Up to 40 miles thick under mountain ranges Consists of mostly “light” rocks (granite – below continents) (basalt – below oceans) Oceans cover 71% of the crust(oceanic crust is very dense) Continental crust is less dense
Oceanic and Continental Crust Note: the directions of movement
Tectonic Plates • Earth’s crust is broken into about 19 pieces • These plates move on top of the asthenosphere
Earth’s Layers Are Earth’s layers similar to a hard boiled egg?
The Yolk =core , inner & outer core Egg white =mantle The Shell =crust How Are Earth’s Layers Similar To a Hard Boiled Egg?
Other Physical Structures of the Earth’s Layers • Lithosphere- includes the crust and the upper most portion of the asthenosphere. This area glides over the rest of the upper mantle. Zone of earthquakes/volcanoes. • Asthenosphere- top layer of the upper mantle which consists of highly viscous rock that flows slowly (like hot asphalt)