Topic: Plate Boundaries

Plate Tectonics Theory: -

Major 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 -

3 things can happen at plate boundaries - - -

Convergent Plate Boundaries ----

Oceanic crust vs. Continental Crust Granite, less denseBasalt, Denser

Example: Cascade Mountains /terc/content/visualizations/es0804/es0804pa ge01.cfm?chapter_no=visualization

Trench - Subduction— Area of Subduction

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

Indian Subcontinent Moving Toward Asia ience/terc/content/visualizations/es0804/e s0804page01.cfm?chapter_no=visualizatio n

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 Boundaries Plates move apart

Rifting zone on Land

Rifting zone under the ocean

Mid Atlantic Ridge

Mid-Ocean Ridge A divergent boundary, - Basalt forming

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 -

San Andreas Fault California

Transform Features: 1)- Example: San Andreas Fault, CA, USA

FQ: Why does oceanic crust subduct under continental crust? --