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! Earthquakes! Mountain ranges! 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 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? Dollar bill, football, mechanical pencil, key

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

Two plates are SLIDING PAST each other TRANSFORM BOUNDARIES Two plates are SLIDING PAST each other CRUST CRUST

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. WHAT IS THE THEORY OF PLATE TECTONICS? WHAT IS A RIFT VALLEY? HOW IS IT FORMED? WHAT 3 TYPES OF PLATE MOVEMENT OCCUR AT PLATE BOUNDARIES 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