Download Plate Tectonics

Plate Tectonics…what is it?
Plate tectonics is the theory that explains
the formation, movement and subduction
of Earth’s plates
How do the Plates move?
 The plates of the Earth move because of Convection Currents
in the asthenosphere rising and causing the movement.
What happens when the plates
move?
 No plate can budge without affecting
the other plates surrounding it.
 As the plates move, they collide pull
apart, or grind past each other
producing changes in the Earth’s
surface.
What kind of Changes?
Volcanoes!
Mountain ranges!
Earthquakes!
Sea-trenches!
Where are these plates?
IN THE LITHOSPHERE!
PROOF or it didn’t happen…
EVIDENCE #1
The continents used
to fit together like
puzzle pieces before
the plates moved them
apart
Scientists call this
Supercontinenet: PANGAEA
How do I say that?? PAN-GEE-UH
As the plates continued to move and
separate, OCEANS formed
Landmasses collided and split apart until
they ended up where they are now
PROOF or it didn’t happen…
EVIDENCE #2
Fossils on different continents are similar to
fossils on continents that were once
connected.
When the continents split, different life
forms developed.
Continents that were once connected also
have identical landform shapes and
features and identical rock formations
PROOF or it didn’t happen…
EVIDENCE #3
Most features on land and in the ocean are the result of geological
activity and earthquakes along plate boundaries (where the pieces
meet).
The exact patterns depend on HOW the plates are moving… together
– apart – or sliding.
What else do we know?
The plates are still moving!!
Though they move VERY SLOWLY 
between 1-10 centimeters per year
What else do we know?
There are places within the lithosphere
where magma rises and leaks through the
crust
This is called a HOT SPOT and is where
volcanic activity occurs.
HOTSPOTS are how the Hawaiian islands were
formed!!
REVIEW CHECK
Where are the Tectonic plates located?
What part of the Earth do they float on?
How do they move?
FALCON FOCUS
Write your answer on your Wednesday
Falcon Focus spot
A MAN WAS DRIVING HIS TRUCK
AND THE MOON WAS NOT OUT.
HE DID NOT HAVE HIS
HEADLIGHTS ON. A WOMAN WAS
CROSSING THE ROAD IN FRONT
OF HIM, SO HOW DID HE SEE
HER?
MAP IT
https://earthquakes.volcan
odiscovery.com/
Plate Boundaries
Plates float on the upper mantle (Asthenosphere)
They move due to Convection Currents
The edges of the different plates meet at lines called
Boundaries
At the border of plate boundaries are….
FAULTS—breaks or cracks in the
Earth’s crust
Types of Boundaries
There are 3 different types of
boundaries that occur because of their
different movement
 Convergent Boundaries
 Divergent Boundaries
 Transform Boundaries
Convergent Boundaries
 2 plate boundaries come together or
collide
 A collision is when two plates hit
each other
CRUST
CRUST
What happens when they hit?
 The DENSITY of the crustal plates
colliding determines if either…
A) One plate goes under the other
B) The plates rise up
Either way…. An Earthquake can always (and
often does) occur when two plates interact
Collisions
PREDICTION TIME: Basalt (what
Oceanic Crust is made out of) is
more dense than Continental Crust.
What do you think will happen
to the plate that is MORE
dense?
CONVERGENT BOUNDARIES
CRUST INVOLVED: OCEANIC & CONTINENTAL
OCEANIC & OCEANIC
MOVEMENT: More dense plate (Oceanic) slides
under or sinks below the less dense Continental
plate.
*****COLLIDE*****
FORCE/STRESS ON THE ROCK: Compression
(push or squeeze rocks)
LAND FORMS:
 Trenches, crust going below into the mantle melts and
recycles
 Island arcs and volcanic arcs (small mountain ranges)
SUBDUCTION ZONE
SUBDUCTION ZONE
TRENCHES
ISLAND ARC
VOLCANIC ARC
CONVERGENT BOUNDARIES
CRUST INVOLVED: CONTINENTAL & CONTINENTAL
MOVEMENT: Both plates buckle and push up
FORCE/STRESS ON THE ROCK: Compression (push or
squeeze rocks)
LAND FORMS:
Mountain ranges
Volcanoes
AND EARTHQUAKES!
THURSDAY FALCON FOCUS
These everyday objects have been magnified! Can
you guess what they might be?
VIDEO
https://www.youtube.com/watch?v=GyMLlLxbfa4
Let’s try it!
Plates Interactive
DIVERGENT BOUNDARIES
Two plates are MOVING APART
CRUST
CRUST
DIVERGENT BOUNDARIES
CRUST INVOLVED: ANY
MOVEMENT: Two plates are moving apart
****DIVIDE****
FORCE/STRESS ON THE ROCK: Tension (pulling
apart of rocks)
LAND FORMS: New crust forms as magma
pushes up and hardens in the Rift Zone between
separating plates (known as Seafloor Spreading)
Mid-ocean ridges
DIVERGENT BOUNDARIES
Mid Ocean Ridge
Magma comes up through the crust under the ocean and cools and
hardens.
This forms NEW CRUST!
As this happens, the OLDER crust moves AWAY from the ridge.
IN THE NEWS
SAN ANDREAS FAULT
TRANSFORM BOUNDARIES
CRUST
CRUST
Two plates are SLIDING PAST
each other
TRANSFORM BOUNDARIES
CRUST INVOLVED: ANY
MOVEMENT: Two plates are sliding past each
other
*****SLIDE*****
FORCE/STRESS ON THE ROCK: Shearing
(causes sliding of rocks)
LAND FORMS: Crust is NOT created or destroyed
LOTS OF EARTHQUAKES!!!!
TRANSFORM BOUNDARIES
Table Team Work
1. On the back of your notes sheet, fill out the
questions about the pictures show with your groups.
2. Then answer the following questions on ONE SHEET
of paper.
1. WHAT IS THE THEORY OF PLATE TECTONICS?
2. WHAT IS A RIFT VALLEY? HOW IS IT FORMED?
3. WHAT 3 TYPES OF PLATE MOVEMENT OCCUR AT PLATE
BOUNDARIES
4. WHAT MAJOR EVENT BEGAN ABOUT 225 MILLION YEARS
AGO?
FRIDAY FALCON FOCUS
Get out a sheet of paper,
title it Joy Journal Entry
#3 and begin writing
your journal entry.
FIRST PERIOD
 Get out a blank sheet of paper,
title it Joy Journal Entry #3 and
study your vocab