RETAKE Tectonic Plates Review

RETAKE Tectonic Plates Review

By Ms. Knyfd 2022

From the outside to the inside, we have 4 layers:

• Crust (solid)

• Mantle (flexible solid)

• Outer Core (liquid)

• Inner Core​ (solid)

​

There are also the Lithosphere and Asthenosphere.

• Lithosphere: lower part of the crust and upper part of the mantle (solid)

• Asthenosphere​: the part of the mantle that includes the convection currents (flexible solid)

​Earth's Layers

​The inner core is solid because of the increased pressure from going further into the earth.

Convection currents happen in the mantle / asthenosphere.

As fluids get hot, they become less dense & rise.​

​

As fluids get cool, they become more dense & fall.​

Convection Currents

Multiple Choice

From the last two slides, convection currents happen in which flexible layer?

• Mantle / Asthenosphere

• Crust

• Outer Core

• Inner Core

Fill in the Blanks

The inner core is SOLID because the

increases as you go deeper into earth.

When all the continents once formed a giant landmass.

​

Pangea

All of the edges of the continents looked like they fit together like puzzle pieces.

Continent Edges​

​

Fossils of the same plants and animals were found on different continents.

Fossils

Mountain ranges on different continents had the same type and age of rocks.

Mountain Ranges

​Wegener's Evidence on Continental Drift

He could NOT PROVE how the continents moved.

Why was Wegener's theory NOT

accepted?

Open Ended

Explain what Pangea was in your own words.

Multiple Choice

Which of the following was NOT a piece of evidence that Wegener used?

• mountain ranges on different continents with the same age and type of rocks

• how the continents moved

• fossils of the same plants and animals found on different continents

• the edges of the continents looked like puzzle pieces that fit together

Fill in the Blanks

People did not believe Wegener because he could not prove how the continents

.

Type of Motion: toward each other; collide with each other​

Result: mountains, trenches, earthquakes, subduction, volcanoes

​Example: ​Himalayan Mountains

Convergent

​

Type of Motion: away from each other; divide

​

Result: ridges, rifts, new seafloor

​

Example: Mid-Ocean Ridge​

Divergent​

​

Type of Motion: side-by-side

​

​

Result​: earthquakes

​

​

Example: San Andreas Fault​

Transform

​Plate Boundaries

Made of: Granite

​

Less Dense​

​​Continental Plates

Made of: Basalt

​

More Dense

​

Will always subduct under the continental plates​

​​Oceanic Plates

​Two Types of Plates

A place where many volcanoes and earthquakes occur

​

Happen on the tectonic plate boundaries

​​

Happens around the Pacific Ocean/Plate​

Ring of Fire

Multiple Choice

Which plate boundary is most known for earthquakes?

• Divergent

• Convergent

• Transform

• All of the above

Open Ended

What results from convergent boundaries?

Open Ended

What results from divergent boundaries?

Fill in the Blanks

The Ring of Fire is located around the

Ocean and has many volcanoes and earthquakes.

Poll

Continental Plates are made of...

• Basalt

• Granite

Poll

Oceanic Plates are made of...

• Basalt

• Granite

Where new seafloor is made and old seafloor is pushed away

​

New seafloor is made at the MID-OCEAN RIDGE

​

Mid-Ocean Ridge is a divergent plate boundary​

​

Seafloor Spreading

As old oceanic crust moves farther away from the mid-ocean ridge, it becomes more dense.

​

Eventually, it starts to subduct or sink below the continental crust to be recycled and reused. This is at a trench. Trenches happen at convergent plate boundaries.

​

Trenches & Old Seafloor

When one more dense plate sinks under a less dense plate

Subduction

Multiple Choice

What happens at a mid-ocean ridge?

• new seafloor is rising up as molten material

• two oceanic plates are moving away from each other

• old seafloor is being pushed back

• all of the above

Open Ended

Tell me what happens at a trench in your own words.

Fill in the Blanks

Subduction is when one _______ dense plate sinks under a _______ dense plate.