Plate tectonics

Theory of Plate Tectonics

Plate Tectonics

The system of ideas behind plate tectonics theory suggests that Earth's outer shell (lithosphere) is divided into several plates that glide over the Earth's rocky inner layer above the soft core (mantle)

The earth moves!

Our earth moves! We have many pieces of evidence for this some we can even feel; like earthquakes. So what is causes the movement? Magma! Deep in the Earth, molten rock churns as it heats and cools in convection currents. This moves the crustlike plates on top, and even creates and new and destroys old plates. *VIDEO TIME*

Chemical (compositional layers) = what the layers are made up of

Physical (mechanical) layers = how the layers behave

Chemical Layers

• The crust is the thinnest & least dense layer: oceanic crust is THINNER but MORE DENSE than continental crust! The crust is made of igneous rock containing a lot of silicon and oxygen.

• The Mantle is the middle layer. It is hot softened rock containing iron and magnesium.

• The outer core is a very hot liquid. It is made of iron and nickel.

• The inner core is also made of iron and nickel, but solid

Physical Layers

• Lithosphere - crust + uppermost part of mantle = cool, brittle, solid rock. Broken into pieces called tectonic plates

• Asthenosphere: Hot softened rock with areas of melt. Moves slowly: a solid that behaves like a liquid! "Plasticity"

• Mesosphere - lower part of the mantle

• Outer Core - hot liquid that churns - this generates electrical currents that in turn create Earth's magnetic field!

• Inner Core - spinning solid: most dense layer!

Lithosphere, Asthenosphere & Tectonic Plates

• The lithosphere is broken into tectonic plates

• These plates are not connected - they move slowly around the surface of the earth

• The plates float on top of the asthenosphere

Multiple Choice

The lithosphere includes the _____ and part of the _____.

• core, crust

• mantle, core

• crust, core

• crust, mantle

Multiple Choice

As you travel from the inner core to the crust, how would temperature, pressure and density of the material change?

• The would all increase

• The would all decrease.

• Nothing, the layers are made of the same material throughout

• Temperature would decrease, but pressure and density would increase

Multiple Choice

Which layer has the coolest temperatures?

• outer core

• inner core

• mantle

• crust

Multiple Choice

What is the outer core made of?

• solid rock

• solid metal

• melted rock

• melted metal

Multiple Choice

Which layer is made of solid iron & nickel?

• inner core

• outer core

• mantle

• crust

Multiple Choice

This layer is divided into pieces called tectonic plates.

• Mesosphere

• Asthenosphere

• Mantle

• Lithosphere

Multiple Choice

This layer is directly below the crust.

• Crust

• Mantle

• Outer Core

• Inner Core

Multiple Choice

What is the name of the 225 million year old super continent?

• Pancake

• Pangea

• Super Continent Sam

• Albert Einstein

Multiple Choice

How first identified the theory of plate tectonics and Pangea?

• Albert Einstein

• Patrick Henry

• Alfred Wegener

• Mr. Harris

Multiple Select

What are two pieces of evidence that support the theory of plate tectonics?

• Matching rocks/fossils on different continents

• Landscapes that look alike

• The same species live in different areas today

• Seafloor Spreading

Multiple Choice

The lithosphere is one smooth, solid shell around the Earth.

• True

• False

Multiple Choice

In convection currents, hot material ______ and then cool material _____.

• 1) Rises

  2) Sinks

• 1) Sinks

  2) Rises

Multiple Choice

Convergent boundaries occur when:

• Two plates pull apart

• Two plates collide

• Two plates scrape/slide past each other

Multiple Choice

Divergent boundaries occur when:

• Two plates pull apart

• Two plates collide

• Two plates scrape/slide past each other

Multiple Choice

Transform boundaries occur when:

• Two plates pull apart

• Two plates collide

• Two plates scrape/slide past each other

Multiple Choice

Subduction zones occur when:

• Two plates collide at and convergent boundary and one sinks

• Two plates collide at a convergent boundary and they push each other up

• Two plates pull apart at a divergent boundary

Multiple Choice

Seafloor spreading occur when:

• Two plates collide at and convergent boundary and one sinks

• Two plates collide at a convergent boundary and they push each other up

• Two plates pull apart at a divergent boundary

Multiple Choice

Mountain building occurs when:

• Two plates collide at and convergent boundary and one sinks

• Two plates collide at a convergent boundary and they push each other up

• Two plates pull apart at a divergent boundary

Multiple Choice

Alfred Wegener's Theory of Plate Tectonics was laughed at initially, but is now believed by the scientific community.

• True

• False

Convergent Boundaries

• Collide (crash into eachother)

• Create mountains, trenches, volcanoes

• Destroys crust during subduction

Subduction

At a convergent boundary, plates collide. Heavier (more dense) oceanic crust goes under and melts into the mantle. This destroys the crust.

Multiple Choice

How do plates move at CONVERGENT boundaries?

• Collide (together)

• Move apart

• Slide past each other

Multiple Choice

How do CONVERGENT boundaries affect the crust?

• They create crust

• They destroy crust

• They don't destroy or create

Divergent Boundaries

• Plates move apart

• Creates mid - ocean ridges and rift valleys

• Creates new crust through Seafloor Spreading

Multiple Choice

How do plates move at DIVERGENT boundaries?

• Collide (together)

• Move apart

• Slide past each other

Multiple Choice

How do DIVERGENT boundaries affect the crust?

• They create crust

• They destroy crust

• They don't destroy or create

Multiple Choice

What type of boundary occurs when two tectonic plates separate?

• divergent

• convergent

• transform

Multiple Select

Which tectonic plate(s) can cause earthquakes? Choose all that would.

• Converging

• Diverging

• Transforming

Multiple Choice

Which feature will most likely result from transforming plate tectonics?

• a hurricane
• an earthquake
• a drought
• a blizzard

Multiple Choice

what is this ????

• transform

• divergent

• convergent

Multiple Choice

Name the boundary

• convergent boundary
• divergent boundary
• transform boundary
• sergent boundary

Multiple Choice

Name the boundary

• convergent boundary
• divergent boundary
• transform boundary
• sergent boundary