Download - 9/15/11 and 9/16/11
9/15/11LEQ: HOW does continental drift happen? (reminder: complete sentences!)
1. What is Pangaea?2. What is the theory of continental drift?3. What different types of evidence do we have to support this theory?4. Is it possible to find ice evidence in Jamaica? Explain.
Today’s LEQ: How does continental drift happen?
By the end of today, you should be able to…
1. Explain the geologic conditions that allow continents to move
2. Describe convection currents that cause the continents to move
KEY VOCABULARY
8. Plate tectonics9. Convection Currents10. Lithosphere11. Asthenosphere
Activating Strategy http://www.youtube.com/watch?
v=TzzGPfVx32M
We know that the continents moved apart….BUT HOW IS THIS POSSIBLE?!
LAVA LAMP SCIENCE http://
www.youtube.com/watch?v=VI86kifDOgc&feature=related
HOW DOES A LAVA LAMP
WORK?
WATCH!What was the difference
between when the food coloring was placed over the hot liquid vs. the cold liquid?
Demo Time!
Making observations: WATCH THE EARTH’S MANTLE!
http://education.sdsc.edu/optiputer/flash/convection.htm
Making Inferences:What do all of these
things have in common?HEAT!
The movement of the food coloring represents the movement of magma in the Earth’s mantle
This movement is what causes Earth’s continents to move away from each other
Key Point
CONVECTION
CURRENTS
DEFINITION: The cycle of magma under the crust as
it heats, rises, cools, and sinks
CAUSES:
DIAGRAM:
EFFECTS:
DIAGRAM:
INNER CORE
OUTER CORE
Mantle
Plates move!
How would the position of the continents have been different if the inner core was made of a solid block of ice and not hot iron?
a. The continents would still be one mega continent, Pangaea
b. The continents would be the same position as they are today
HOT Q:
LITHOSPHERE:
ASTHENOSPHERE:
TECTONIC PLATES:
(THIS GOES UNDERNEATH YOUR FRAYER DIAGRAM)
CONTINENTS ADRIFT What form of matter (solid, liquid, or gas) do you
think the crust is made of?
What about the oceanic crust?!
LITHOSPHERE: the rocky crust and the solid top layer of the mantle
ASTHENOSPHERE:
TECTONIC PLATES:
(THIS GOES UNDERNEATH YOUR FRAYER DIAGRAM)
DEMO: CONTINENTS ADRIFT
What form of matter do you think lies underneath the lithosphere?
(DEMO)
LITHOSPHERE: the solid crust and the rigid top layer of the mantle
ASTHENOSPHERE: the liquid, tar-like layer below the lithosphere
TECTONIC PLATES:
(THIS GOES UNDERNEATH YOUR FRAYER DIAGRAM)
LITHOSPHERE: the solid crust and the rigid top layer of the mantle
ASTHENOSPHERE: the liquid, tar-like layer below the lithosphere
TECTONIC PLATES: huge slabs of the lithosphere that move because of convection currents
(THIS GOES UNDERNEATH YOUR FRAYER DIAGRAM)
CONVECTION
CURRENTS
DEFINITION: The cycle of magma under the crust as
it heats, rises, cools, and sinks
CAUSES:
Hotter core temperatureLiquid asthenosphereRigid lithosphere
DIAGRAM:
EFFECTS:
Tectonic plates “drift” apart!
Steps of Convection Comics!!1. Use the list at your desk to put the steps of
convection in order (the first one is done for you)
2. Draw a comic strip for the four steps of convection currents!
3. Your comic strip should include:A) 4 boxes (1 for each step in the cycle)B) 4 illustrationsC) the four steps of convection (you may copy the 4 steps exactly if you like, but you are encouraged to be creative!)Liquid magma in the
mantle is heated by the earth’s core
(add illustration
here)
EXAMPLE:
SUMMARIZER Watch the video again This preview is for a movie called
“Ice Age: Continental Drift” In 3 sentences or more, explain why the
continents ACTAULLY move—(hint—it is not because of a squirrel running around…)
YOU MUST USE EACH OF THE FOLLOWING VOCABULARY FOCUS WORDS in your answer!!!-Lithosphere-Asthenosphere-Convection Current(s)-Tectonic plates
What is the name of the mega continent? Who proposed the theory of continental drift? What is the theory of continental drift? What are the 3 types of evidence that support
this theory? Why do the continents move apart? How do convection currents cause the plates to
move? Why is it possible we could find fossils of tropical
plants in Alaska? How is it possible that similar animal fossils are
found on two separate continents?
Let’s REVIEW: Earn your seat