Plate TectonicsPlate TectonicsHow did a glacier form How did a glacier form

over hot, arid Australia? over hot, arid Australia?

Alfred WegenerAlfred Wegener Thought the earth’s climate had changed in Thought the earth’s climate had changed in

some areas.some areas. Noticed that the continents fit together like a Noticed that the continents fit together like a

puzzle.puzzle. Named all land Pangaea which means “ all Named all land Pangaea which means “ all

Earth”. Earth”. 1912 – proposed the hypothesis of continental 1912 – proposed the hypothesis of continental

drift.drift. Was not able to explain how the continents Was not able to explain how the continents

drifted.drifted. Theory was not accepted by scientists at that Theory was not accepted by scientists at that

time.time.

Evidence of Continental Evidence of Continental DriftDrift

Fossils Climate RocksFossils Climate Rocks

Fossil EvidenceFossil Evidence Fossils: LystrosaursFossils: Lystrosaurs Small ,squat, doglike reptile lived 200 Small ,squat, doglike reptile lived 200

million years ago.million years ago. Lived near fresh water rivers and Lived near fresh water rivers and

swamps.swamps. Found bones and teeth in South Found bones and teeth in South

Africa and Antarctica.Africa and Antarctica. If the animal could have swam from If the animal could have swam from

present day South Africa to present present day South Africa to present day Antarctica fossils would have day Antarctica fossils would have been found in other areas as well.been found in other areas as well.

Climate EvidenceClimate Evidence

Fossil – Glossopteris Fossil – Glossopteris Fern that grew in Africa, Fern that grew in Africa,

Australia, India, South Australia, India, South America, and Antarctica.America, and Antarctica.

Supports the idea that all Supports the idea that all these continents had a these continents had a similar climate at one time.similar climate at one time.

Rock EvidenceRock Evidence

Similar rock Similar rock structures are structures are found on different found on different continents.continents.

Appalachian Appalachian Mountains in United Mountains in United States match rocks States match rocks in Greenland and in Greenland and Western Europe.Western Europe.

Rocks in South Rocks in South America and America and Western Africa are Western Africa are similar in structure.similar in structure.

Pangaea PuzzlePangaea Puzzle

Cut out your Pangaea puzzle.Cut out your Pangaea puzzle. Assemble the puzzle.Assemble the puzzle. Color the land green and the Color the land green and the

water blue.water blue. Glue the puzzle to your Glue the puzzle to your

construction paper.construction paper. Put your name on the bottom of Put your name on the bottom of

the puzzle and bring it to me.the puzzle and bring it to me. Best looking puzzle gets a prizeBest looking puzzle gets a prize..

Ticket Out The DoorTicket Out The Door

In one paragraph (5 to 7 In one paragraph (5 to 7 sentences) and using your best sentences) and using your best cursive handwriting, answer the cursive handwriting, answer the EQ for today:EQ for today:

How did a glacier form over hot, How did a glacier form over hot, arid Australia?arid Australia?

Seafloor SpreadingSeafloor Spreading

How do continents move?How do continents move?

Harry HessHarry Hess 1960 – proposed the 1960 – proposed the

theory of seafloor theory of seafloor spreading as an spreading as an explanation of how explanation of how the continents drift.the continents drift.

Hot, less dense Hot, less dense material below the material below the Earth’s crust rises Earth’s crust rises toward the surface toward the surface at the mid-ocean at the mid-ocean ridges ridges

Flows sideways Flows sideways away from the ridge away from the ridge in both directions.in both directions.

Evidence of Seafloor SpreadingEvidence of Seafloor SpreadingAge of Rocks, Magnetic Clues, Life FormsAge of Rocks, Magnetic Clues, Life Forms

Evidence of Seafloor spreadingEvidence of Seafloor spreading

Rocks close to the mid-ocean ridge Rocks close to the mid-ocean ridge are younger than rocks further away are younger than rocks further away from the mid-ocean ridge.from the mid-ocean ridge.

Magnetic reversals in rocks show that Magnetic reversals in rocks show that new rock is being formed at mid-new rock is being formed at mid-ocean ridges.ocean ridges.

Heat and chemicals near mid-ocean Heat and chemicals near mid-ocean ridges sustain exotic life forms in ridges sustain exotic life forms in deep water.deep water.

How does sea-floor spreading add How does sea-floor spreading add material to the ocean floor?material to the ocean floor?

Find the center of your paper and using your ruler Find the center of your paper and using your ruler draw a line across the paper.draw a line across the paper.

Measure 3 inch sections from the center line on Measure 3 inch sections from the center line on both sides and draw a line across the paper.both sides and draw a line across the paper.

Continue to draw a line every 3 inches across the Continue to draw a line every 3 inches across the paper.paper.

Number the sections on both outside edges 1, Number the sections on both outside edges 1, and continue to number both sections the same and continue to number both sections the same across the paper.across the paper.

Fold the paper on the center line.Fold the paper on the center line. Place the folded paper between two tables.Place the folded paper between two tables. Pull both ends of the paper at the same time. Pull both ends of the paper at the same time.

QuestionsQuestions

1. What happens at the mid-ocean ridge?1. What happens at the mid-ocean ridge? 2. What forms when the molten material 2. What forms when the molten material

hardens?hardens? 3. What happens to the new ocean floor?3. What happens to the new ocean floor? 4. As shown by your model, how does the 4. As shown by your model, how does the

ocean floor close to the center line differ ocean floor close to the center line differ from the ocean floor near the side?from the ocean floor near the side?

5. What happens at deep-ocean trenches?5. What happens at deep-ocean trenches?

Ticket Out the DoorTicket Out the Door

In one paragraph (5 to 7 In one paragraph (5 to 7 sentences) and using your best sentences) and using your best cursive handwriting, answer the cursive handwriting, answer the EQ for today:EQ for today:

How do Continents move?How do Continents move?

What do Volcanoes, What do Volcanoes, Earthquakes and Earthquakes and

Mountains have in Mountains have in common?common?

Plate TectonicsPlate Tectonics

Plate TectonicsPlate Tectonics

Combines the theories of:Combines the theories of: Continental DriftContinental Drift Seafloor SpreadingSeafloor Spreading Crust of earth is broken into Crust of earth is broken into

plates that move.plates that move. Crust is destroyed and created Crust is destroyed and created

at the same rate.at the same rate.

Types of Plate BoundariesTypes of Plate Boundaries

Divergent – Plates Divergent – Plates move away move away

Example: Mid-ocean Example: Mid-ocean Ridge, Rift ValleysRidge, Rift Valleys

Transform – Plates Transform – Plates slide in the same or slide in the same or opposite directions opposite directions

Example:Example: EarthquakesEarthquakes

Types of Plate BoundariesTypes of Plate Boundaries Convergent – Plates Convergent – Plates

move togethermove together Subduction Zones:Subduction Zones: Ocean and Ocean and

continental plates continental plates collide, forms collide, forms volcanoes.volcanoes.

Continental plates Continental plates collide, formscollide, forms mountains.mountains.