Structure and Movement Structure and Movement of the Earthof the Earth

Structure, Shape, and Internal Structure, Shape, and Internal Systems of the EarthSystems of the Earth

Three Main Layers of the EarthThree Main Layers of the Earth

• Core-center of the earth– divided into two layers: Iron and Outer

• Mantle-Layer of the earth that is between the Earths core and crust– about 1800 miles thick– divided into two layers: upper and lower

• Crust- Thin layer of rock at the earths surface– contains the lithosphere (Plate tectonics)

Core, Mantle, Crust DiagramCore, Mantle, Crust Diagram

On and Above the EarthOn and Above the Earth

• Atmosphere: layer of gases surrounding earth• Lithosphere: upper part of crust (solid rock)

forming continents and ocean floors• Hydrosphere: water elements on earth (rivers,

oceans, lakes and water in atmosphere)• Biosphere: where people/animals and plants

live (atmosphere+lithoshere+hydrosphere)

Internal Forces Shaping the Internal Forces Shaping the EarthEarth

• Continental Drift: The idea that all of the continents were once joined together as one super-continent called Pangaea, which spread apart into 7 continents over 200 million years (p 29)

D:\assets\interactives\wgy29.html

PangaeaPangaea

Internal Forces Shaping the Internal Forces Shaping the EarthEarth

• Earthquakes– Caused by the collisions and movement of

Tectonic Plates(p37) (Moving pieces of the Earths lithosphere)

– The line where plates meet is called a Fault Line(p 39)

– The Richter Scale(1-10…10 being worst) uses information collected by Seismographs to determine the strength of an earthquake

– The point on the surface directly above the source of the quake is called the epicenter.

D:\assets\interactives\wgy37.html

Fault LinesFault Lines

TsunamiTsunami

• When an earthquake occurs under the ocean, it can create a large wave which is called a tsunami,

• These waves can be 50-100 ft tall, and can travel at 450 mph

VolcanoesVolcanoes

• Most Volcanoes found along tectonic plate boundaries

• Ring of Fire- a zone around the rim of the Pacific ocean which is the location of the majority of active volcanoes in the world (map on page 37)

D:\assets\interactives\wgy37.html