​Practice with purpose games and word wall

There was once a time when you could take a stroll from North or South America to Africa no problem!

Plate tectonics theorizes that Earth's outer layer is made up of large, moving pieces called plates! These plates are in constant motion.

Assignment: EdPuzzle

Title:
What are Tectonic Plates? Our Earth and Its Movements
After video: class discussion:
What are the basic layers of the Earth?
What are the possible outcomes of plate movement?
How do fossils support the idea of Pangea, the super continent?
If the inner core is so hot why is it solid?

Tectonic plates move about as fast as your fingernails grow -

That's 1-6 inches a year!

3 Theories of plate tectonics
Convection
Slab pull
Ridge Push.

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What causes tectonic plates to move?

​Convection

the movement caused within a fluid by the tendency of hotter and therefore less dense material to rise, and colder, denser material to sink under the influence of gravity, which consequently results in transfer of heat.

These plates move due to heat from Earth's core.

• Heat rises at spreading centers, pushing plates apart

• This process resulted in the breakup of Pangea, the formation of the Atlantic Ocean, and how Earth's surface appears today!

slab pull

This force is  caused by the sinking of cold, dense mantle material at subduction  zones. As the old mantle material sinks back into the Earth, it pulls  the tectonic plates along with it.

​subduction zones are where the slabs are pulled underneath (because they cool and are more dense)

the upward movement of hot mantle material at mid-ocean  ridges. As the new mantle material rises to the surface, it pushes the  older, cooler mantle material away. This creates a ridge push force that  moves the tectonic plates apart.

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Ridge push

Through collisions, plates can raise incredible mountain ranges!

The Himalayan mountains formed as the Indian plate crashed into the Eurasian plate.

Types of Plate Boundaries

Describe the different types of plate boundaries

Divergent Boundary

- Place where 2 plates move apart

-Most occur in the ocean and form mid-ocean ridges

-When they occur on land, rift valleys form

Divergent Oceanic

-Example-Mid Atlantic Ridge

Transform Boundary

-Place where two plates slip past each other side by side

- Crust is neither created nor destroyed

-Earthquakes frequently occur along these boundaries

That's right! Next time you hike in Shenandoah National Park, know that you are among mountains that started forming over 400 million years ago (that's before life even left the ocean!).

Thank you!