INTERNAL FORCES OF THE EARTH

4 layers of earth 1-crust

Where people live; continents stuck into crust 2-mantle

“hot liquid rock-magma”; like hot caramel 3-outer core 4-inner core

PLATE TECTONICS

Crust is divided into stiff, moving plates

RING OF FIRE

AREA IN PACIFIC WHERE PLATE IS THINNER MORE EARTHQUAKES & VOLCANOES

VOLCANOEHTTP://WWW.VOLCANO.SI.EDU/WORLD/REGION.CFM?RNUM=13S BY REGION

3-MIDDLE OF PLATE

LESS INTERNAL FORCES—HEAT & PRESSURE MORE EXTERNAL FORCES-WIND & WATER

EXAMPLE OF SPREADING--

Plate APlate B

MidOceanic Ridge

“underwaterVolcano”Sea floorspreads

PLATE MOVEMENT

FOLDING

PLATES COLLIDING 2

FAULT- PLATE CRACKS & MOVES

TRENCH CREATION—SUBDUCTIONSMALLER PLATE GOES UP/BIG PLATE GOES DOWN

TRANSFORM—PLATES SLIDE PAST

EARTHQUAKE ZONESPLATES SLIDE PAST EACH OTHER

RESULTS OF INTERNAL FORCES

Types of landforms created Mountains, valleys, volcanoes, islands

What do they look like? Higher, jagged, steep slopes

Primary landforms Created by heat & pressure, plate movement

EXTERNAL FORCES

Rock weathering

Water -breaks rock down Transports rock

WIND

Transports rocks & minerals Breaks down rocks (2 rocks run into each

other0 Creates sand dunes

GLACIERS

Heavy ice Flattens land Picks up sediment Leaves some parts behind as it moves

Creates: Plains Fertile land Carves out rivers Leaves ice that will melt to become lakes

RESULTS OF EXTERNAL FORCES

TYPES OF LANDFORMS Plains, plateaus, alluvial fans, deltas,

LOOK LIKE? Lower in elevation, rounded, smaller

SECONDARY Created by external forces like wind, water,

glaciers

CONTINENTAL DRIFT THEORY

PANGAEA

Evidence #1-Jigsaw PuzzleAll continentsSeem to fittogether

EVIDENCE

2-fossil remains

EVIDENCE #3-SEA FLOOR SPREADINGHTTP://WWW.TECTONICS.CALTECH.EDU/OUTREACH/ANIMATIONS/DRIFT.HTML Sea floor spreading