11/14/2012
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PLATE TECTONICS
Science with Mr. Gluckin
11/14/2012
Please get a piece of paper &
something to write with.
Questions …
Ohio Content Standard
• Earth and Space Sciences E
• Describe the processes that contribute to the continuous changing of Earth's surface (e.g., earthquakes, volcanic eruptions, erosion, mountain building and lithospheric plate movements).
• I know how mountains, volcanos and valleys are formed.
Today’s Session
• Today’s Topics
– Time scale
– Continental drift
– Plate Tectonics
– Plate Boundaries
• Coming Events
• Study Island
KEY WORDS
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tectonic plate convection
fault
hotspot mid‐ocean ridge
subduction
volcano
• geyser
• earthquake
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11/14/2012
Time Scales
• Can you see a tree grow?
• Or the grass?
• Or your fingernails?
Geological Time is verrrry slow!
• Continents move, but very slowly.
• Just a few centimeters per year.
• No, but you see the result after the passage of time.
What events on the earth are very slow?
What events on the Earth are very fast?
Question? Look at the map below, do see any
puzzle pieces, if so where would they fit?
Now do you see?
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11/14/2012
Historical Perspective
The locations of certain fossil plants and animals on present‐day, widely separated continents would form definite patterns (shown by the bands of colors), if the continents are rejoined.
• Wegener, 1912: Shapes of continents and fossils
• Theory of “Continental Drift”
Continental Drift was generally rejected.
Map of Earth's Tectonic Plates
• Wegener could not come up with a way for the continents to actually move. • After his death, new evidence from ocean floor exploration and other studies rekindled interest in Wegener's theory, ultimately leading to the development of the theory of plate tectonics.
• http://www.youtube.com/watch?v=T1‐cES1Ekto
What happens at plate boundaries?
• The border between two tectonic plates is called a boundary. All the tectonic plates are constantly moving — very slowly — around the planet, but in many different directions.
• Some are moving toward each other, some are moving apart, and some are sliding past each other. Because of these differences, tectonic plate boundaries are grouped into three main types. "Ring of Fire”
Volcanic activity is common at convergent plate boundaries.
http://www.learner.org/interactives/dynamicearth/plate.html
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11/14/2012
What was the first theory that involved moving continents called?
A. Continental movement theory
B. Continental drift theory
C. Continental puzzle theory
D.Continental float theory
What was the first theory that involved moving continents called?
A. Continental movement theory
B. Continental drift theory
C. Continental puzzle theory
D.Continental float theory
Kinds of faults
This movement of plates causes stress in some parts of the crust, especially at the boundaries where two different plates are touching each other.
• Faulting: The stress along a fault is released when the pieces of crust move. The rocks rubbing together can cause an earthquake. Earthquakes
http://www.iris.edu/hq/programs/education_a
nd_outreach/animations/2
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11/14/2012
Tsunamis
Folding
• Large areas of folding may form valleys or mountains.
Hot Spots
Current research is exploring whether hotspots remain fixed in position or shift locations.
• There are many places on Earth's surface where the outward transfer of Earth's internal heat is concentrated. Often, these areas are hotspots, which are areas of concentrated, long‐
lasting volcanic activity.
Geysers
Exit Quiz
• Hydrogeologic features called geysers are often found at hotspots, as well as at areas of volcanic activity in general. Geysers are eruptions of hot water from the ground.
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11/14/2012
Science Zone
• Tuesdays and Thursdays
• 4pm‐5pm
• Come get your questions answered about the lesson or about Study Island.
FILE TRANSFER – Today’s Slides
Remember to complete your Study Island lesson
for this week by 4pm Thursday!
Eighth Grade 2F: Plate Tectonics
QUESTIONS / DISCUSSION
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3.
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