Overview
Tectonics
PSC 152
Review
What are the layers of the geosphere?
What is the main energy source in the geosphere?
What is the main form of heat transfer?
Convective motion
Animation (convection causes tectonics)
Drags material on surface
Develops cracks and collisions
In this section:
What is tectonics?
What causes tectonics?
What effects do we see?
Tectonics
Definition from vocabulary ?
Basically deals with how the interior is changing
and how that effects the surface
Tectonic plates
Large pieces of lithosphere which move as one
piece
See figure on next slide
Plates
Continental Drift
convection moves plates
Over long time, continents move
past movement animation
future movement animation
Two types of crust
Oceanic
Continental
Crust under the
ocean
Thinner
Younger
Crust on the
continents
Thicker
Older
Plate Boundaries
Plate Boundaries
What happens at the edge of the plates?
It depends on how the plates are moving relative to
each other…
3 types of boundaries
What would be the possible directions of motion?
animations
Convergent
Divergent
Transform
Transform Boundaries
Plates move sideways past each other
What do you think will happen?
Plates strain and deform
Eventually too much strain
Earthquake
Divergent Boundaries
Plates move away from each other
What do you think will happen?
Crust will crack, earthquake
Magma flows up into crack
Magma cools and forms new rock
Animation
Divergent
Oceanic-Oceanic
Mid-ocean ridge
Animation
Continental-Continental
Great African Rift Valley
Convergent
Oceanic-Oceanic
What do you think will happen?
Animation
Convergent Boundaries
Plates move toward each other
What do you think will happen?
Plates may bend
One plate may slip under the other
Depends greatly on what type of crust
Convergent
Oceanic-Continental
What do you think will happen?
Animation
Convergent
Continental-Continental
What do you think will happen?
Animation
In-Class Activity
In groups of 2-3
Answer questions on the handout worksheet about
tectonics
Locations of effects
Where are you most likely to find mountains?
Where are you most likely to find volcanoes?
Where are you most likely to find earthquakes?
Tutorial maps