NSSS1.1

toc =1.1 Earth's Crust in Motion=

Vocabulary

 * Geologists:** scientists who study the forces that make and shape the earth
 * Geology**: the study of planet Earth
 * Constructive forces**: forces that build up landmasses like mountains
 * Destructive forces**: forces that slowly wear away mountains and surface such as what an ocean does
 * Continents**: seven large landmasses on earth
 * Seismic waves**: waves that move through the Earth's interior
 * Pressure**: force pushing on a surface or area
 * Crust**: layer of rock that makes up the Earth's outer skin
 * Basalt**: dark, dense rock that forms the oceanic crust
 * Granite**: rock with larger crystals that is less dense than basalt and makes up the continental crust
 * Mantle**: layer of hot rock below the crust
 * Lithosphere**: means "**stone**" and is the mantle and crust together
 * Asthenosphere**: means "**weak**" soft rock material that can flow slowly
 * Outer core**: layer of **molten** metal that surrounds the inner core
 * Inner core**: dense ball of **solid** metal

Science of Geology

 * studying surface changes
 * surface always changing
 * finding indirect evidence
 * cannot see inside earth
 * use seismic waves
 * speed of waves tells the material

Center of the Earth

 * temperature
 * surface rock is cool
 * 20 meters/warmer
 * every 40 meters 1 degree celsius hotter
 * boy that's hot
 * pressure
 * deeper you the greater the pressure

The Crust

 * continental
 * granite
 * light colored rock
 * oceanic
 * basalt
 * dark colored rock

The Mantle

 * 40 meters below, you cross the crust's boundary and into the mantle.
 * Crust and uppermost part of mantle are part of lithosphere
 * Lower part of mantle is called asthenosphere
 * Mantle is 3,000 meters deep

The Core

 * Outer core
 * made of molten iron and nickel
 * behaves like a thick liquid
 * Inner core
 * a dense ball of metal
 * under immense pressure so atoms can't expand and become liquid
 * Misc.
 * core makes one third of Earth's mass, but only 15% of its volume
 * together slightly smaller than the Earth's own moon

Earth's magnetic field

 * Currents in outer core force inner core to spin creating a magnetic field.