Topic: Plate Boundaries

Plate Tectonics Plate Tectonics Theory: Theory:

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Major ConceptsMajor Concepts

The lithosphere is divided into 6 major plates

Pacific, American, Indian, African, Eurasian, Antarctic

There are also many smaller plates as well

What would cause the lithosphere plates to move?

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Plate Boundaries

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3 things can happen at plate boundaries

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Convergent Plate Convergent Plate BoundariesBoundaries

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Oceanic crust vs. Continental CrustGranite, less denseBasalt, Denser

Example: Cascade Mountains

http://www.classzone.com/books/earth_science/terc/content/visualizations/es0804/es0804page01.cfm?chapter_no=visualization

Trench-Subduction—

Area of Area of SubductionSubduction

Continental vs. Oceanic

Result: -

Features: 1) -2) -3) -Example: Cascade Mts., West US

Oceanic crust vs. Oceanic crust

Oceanic vs. Oceanic

Result: -

Features: 1) -2) -3) -Example: Mariania Islands, Pacific

Ocean

Continental crust vs. Continental crust

http://www.pbs.org/wnet/savageearth/animations/rift-collide.html

Indian Indian Subcontinent Subcontinent

Moving Moving Toward AsiaToward Asia

http://www.classzone.com/books/earth_science/terc/content/visualizations/es0804/es0804page01.cfm?chapter_no=visualization

Mount Everest is 29,035 ft Grows Larger Each Year Due to Tectonic Forces

Continental vs. Continental

Result: -

Features: 1) -2) -Example: Himalayas Mountains

Diverging Plate BoundariesPlates move apart

Rifting zone on Land

Rifting zone under the ocean

Mid Atlantic Ridge

Mid-Ocean Ridge

A divergent boundary, -

Basalt Basalt formingforming

Mid-Atlantic Ridge Underwater

Mid-Atlantic Ridge above

sea level

Iceland

Diverging Plates

Result: -

Features: 1) -2) -3) -4) -Example: Mid-Atlantic Ridge

Transform Plate Boundaries

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San Andreas Fault

California

Transform Features: 1) -

Example: San Andreas Fault, CA, USA

FQ:

Why does oceanic crust subduct under continental crust?

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