Transcript To the teacher

Plate Tectonics: Features: TEKS 8.9B
To the teacher:
• This CPO Science PowerPoint presentation is designed to guide you
through the process of presenting the lesson to your students. The
presentation uses a 5-E teaching model: Engage, Explore, Explain,
Elaborate, and Evaluate.
• The PowerPoint Slide notes indicate where you may want to bring in
various lesson elements such as quizzes, readings, investigations,
animations, and practice materials. Additional science background
information is provided in the slide notes where appropriate. You can
view these notes by selecting “View,” then “Normal.” You will see the
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• The slides that follow are intended for classroom use.
Plate Tectonics: Features: TEKS 8.9B
Why did this mountain explode?
• On the morning of May 18, 1980,
Washington’s Mount St. Helens erupted
violently for nine hours. A magnitude 5.1
earthquake kicked off the huge explosion.
In just minutes, the 9,677 foot-high
mountain collapsed, reduced 1,200 feet
by the explosion and a mammoth
landslide. So much ash was released that
the sky got dark.
• Mount St. Helens is located along the
boundary of two massive tectonic plates.
The plates move and shift, creating both
volcanoes and earthquakes.
Plate Tectonics: Features: TEKS 8.9B
Time to investigate!
• Complete the lesson investigation:
– Plate Tectonics
Plate Tectonics: Features: TEKS 8.9B
Divergent plate boundaries
• Mid-ocean ridges occur where two plates are moving
apart. This type of boundary is found over the rising
part of a mantle convection cell. As the plates move,
molten rock fills the empty space between them. The
rock cools and becomes new ocean floor.
• Rift valleys occur where
two continental plates
move apart. The East
African Rift Valley is a
famous example.
Plate Tectonics: Features: TEKS 8.9B
Convergent plate boundary 1
• A deep-ocean trench is a valley on the ocean floor
created when an older, denser oceanic plate subducts
under a younger, less dense oceanic plate.
Plate Tectonics: Features: TEKS 8.9B
Convergent plate boundary 2
• What happens when an
oceanic plate collides with a
continental plate?
• The denser oceanic plate
subducts under the
continental plate.
• The Andes Mountains,
pictured here, formed as the
subducting oceanic plate
deformed and pushed up the
land at the edge of the
continental plate.
Plate Tectonics: Features: TEKS 8.9B
Convergent plate boundary 3
• When two continents collide,
mountains form!
• The Himalaya Mountains are the
result of the collision between India
on the Indo-Australian Plate and
China on the Eurasian Plate.
Plate Tectonics: Features: TEKS 8.9B
Transform fault boundary
• A transform fault boundary
occurs where two plates slide
by each other.
• Offsetting occurs when a
feature like a creek or road
crosses a transform fault. The
movement of the fault will
break, or offset the feature,
causing a zig-zag appearance.
• Earthquakes sometimes occur
at transform fault boundaries.
Plate Tectonics: Features: TEKS 8.9B
Time for Practice!
• Complete the lesson practice activity:
– Continental United States Geology
• As you read this activity sheet, make a list of major land
features of the United States and identify which types
of plate movements were
involved in their formation.
Plate Tectonics: Features: TEKS 8.9B
Show what you know!
• Try the lesson’s interactive quiz, or complete a quiz
that your teacher can print out for you.
• Hint:
– You might want to review your lesson reading piece one
more time before
trying the quiz.