APES 11/30 and 12/1

• Please take out your plate tectonics lab and map

• Log in to a computer

• Grab your folder

• Got a soil sample? Label it and put in by the fume hood

Folder Grading

1. 2 current events (both stamped): 20 pts.

2. Unit 3 FRQs: 10 pts.

3. Wolf FRQ: 5 pts.

4. Biome Spreadsheet: 5 pts.

- Graded (mostly!) on completion since you correct your FRQs in class

Learning Targets

Plate Tectonics HW Review

• 5 min: check in with your group to get questions answered. I’ll be circulating!

• Put your gold lab in the inbox and your map in your folder.

What is on AP test:

I. Earth Systems and Resources (10-15%)

A. Earth Science Concepts (Geologic time scale; plate tectonics, earthquakes, volcanism; seasons; solar intensity and latitude)

B. The Atmosphere (Ch. 4)

C. Global Water Resources/Use (after break)

D. Soil and Soil Dynamics (later this week)

What’s Inside the Earth?

Earth Profile by TextureLITHOSPHERE• Hard & brittle• Earth’s Crust +Upper-

most mantle • “Plates”

ASTHENOSPHERE• Highly Viscous • 2nd Upper-most mantle• Convection current

that carries the plates

Ocean and Continental CrustOCEAN crust• Denser• Thinner• Eventually subducted• Relatively young

CONTINENTAL crust• Less dense• Thicker• Rarely/never

subducted• Oldest crust on Earth

Theory of Continental Drift

• Continents were formed from the drifting apart of one super continent Pangaea

• http://www.classzone.com/books/earth_science/terc/content/visualizations/es0806/es0806page01.cfm?chapter_no=visualization

• Found evidence of similar fossils and geological formations on different continents

• The shape of continents also seemed to “fit” together

Fossil & Geologic Evidence

Big flaw with theory: How did the continents actually move?

Theory of Plate Tectonics

• Outer “shell” of Earth is broken into plates (lithosphere)

• Plates are carried by convection cells in asthenosphere

• Moving plates collide, diverge, or slide by each other

• Explained Alfred Wegener’s Theory of Continental Drift

Convection cells in asthenosphere (upper mantle) cause sea floor spreading

Convergent Boundaries

1. Continental/Oceanic•Denser ocean crust is subducted under.•Deep trench, strong earthquakes•Energy of subduction often creates volcanic mountain range on continenthttp://education.sdsc.edu/optiputer/flash/subduction_5.htm

•Examples:

Andes Mts.

Cascade Mts.

• http://www.publicbroadcasting.net/kplu/news.newsmain?action=article&ARTICLE_ID=1402653&sectionID=13

Convergent Boundaries2. Oceanic/Oceanic•Slower plate is subducted (pulled under)•Outcome = volcanic islands, strong earthquakes, tsunamis, deep trenches•Ex: Aleutian islands (Alaska), Hawaiian Islands, Japan, Southeast Asia

http://education.sdsc.edu/optiputer/flash/convergance2.htm

Hot Spots• Magma flows from a weak spot/vent in the

crust creating a volcano

• Crust above the vent is moving

• Forms a chain of land that varies in age down the chain (i.e. Hawaii)

• Why is Nihau the oldest Hawaiian Island? Hawaii the youngest?

• What island still has active volcanoes? In a hundred years will it still have an active volcano? Why or why not?

Types of Volcanoes

• https://www.youtube.com/watch?v=HdhARb2PGqA

• Composite = Alt. layers of lava flows, ash, and cinder

• Infrequent but explosive eruptions

• Usually large and conical

• Occur along subduction zones

Ex: Mt Hood, Mt. Rainier, Mt Shasta

Convergent Boundaries

3. Continental/Continental•Continental Crust is light, so no subduction•Instead, piles of crumpled, folded crust = tall mountains•Examples: Himalayan Mts.,

Appalachian Mts.,

Alps

Himalayan Formationhttp://www.edumedia-sciences.com/en/a823-formation-of-the-himalayas

Divergent Boundary

• Normal Fault

• Mostly below the ocean

• Sea Floor Spreading - Forms new crust• http://education.sdsc.edu/optiputer/flash/seafloorspread.htm

• Example: Mid

Atlantic Ridge, Rift

Valley in Africa

Great Rift Valley- Africa

Age of Seafloor

Transform Plate Boundaries

• 2 plates sliding in opposite directions

• E.g. San Andreas Fault• http://education.sdsc.edu/optiputer/flash/SanAndreas.htm

Faults

• Fractures in crust

• Occur along plate boundaries, but occasionally occur in the middle of a plate

• Rigidity of crust builds up tension; eventually slippage occurs to release tension this is an earthquake

What causes the seasons?• Earth’s Tilt: 23.5 degrees.

• The rotation of the earth around the sun.

• Direct sunlight vs. Indirect sunlight.

Solar Intensity vs. Latitude

• Lower latitudes are nearest to the equator

• They always receive more intense sunlight than “higher” latitudes

• N and S hemispheres differ in solar intensity depending on season

Test Corrections!

• Multiple Choice only– Show new content learning

• All retakes and corrections due Friday– Retakes for scores of 22 and below

• Done early? Find the Ch. 8 assignment and start Module 24.

Due Next Time

• Gold Day:

Module 24 (see online assignment!)