• Update your grade sheet. For the Earth’s Layers WS if you
followed directions you got 10/10. If you didn’t answer the
question on the back or color the diagram you got 8/10. If you
didn’t do either you got 6/10. Write down your assignments.
Assignment
1. Signed Rules & Procedures
2. All About You
Points TotalPoints
Received
Possible
10
5
3. Brain Pop Sci. Meth. WS
10
4. Observation vs. Inference Unit1 Section 2 Notes
10
5. Sci. Meth Quiz
21
6. Tootsie Pop Lab
10
7. Science Pre-Test
10
8. Earth’s Layers WS
10
9. Ch. 7 Section 1 Quiz
15
• Turn in your Pangaea Lab. Find your seat and
get your half sheet of paper out from yesterday.
On your paper, answer the following questions:
Do not open your book
• 1. What is the title of Ch. 7 Section 2
• 2. What were the Terms to Learn for Ch. 7
Section 2?
• 3. In 3-5 sentences, explain the main idea of
Ch. 7 Section 2.
• 1. Ch. 7 Section 2 Discussion and
Demonstrations.
• 2. Plate Tectonics WS?
Restructuring Pangaea Lab
Question of the Day
• Besides the shape of the continents, what
other evidence shown in the map below
supports the Pangaea theory?
QuickTime™ and a
TIFF (Uncompressed) decompressor
are needed to see this picture.
What was Pangaea?
• Has the world always looked as it does today?
What was Pangaea?
• Pangaea means ‘all
land’ in Greek
• 245 million years ago
Earth’s continents were
joined together to form a
supercontinent known as
Pangaea.
Reconstructing Pagaea Lab
• 1. Label the 6 continents, including Greenland,
before cutting them out.
• 2. When you are cutting, cut as close to the
edge of the continents as possible. Don’t cut
out the islands.
• 3. Outline the edge of each continent with a
different color.
• 4. There will not be enough scissors for
everyone to cut out at the same time, so if you
do not have scissors do step 3 first.
Ch. 7 Section 2 Restless Continents
• What do we mean when we say Restless
Continents?
• Continental drift- theory that continents can
drift apart and have done so in the past.
I. Drifting Continents
• Why did Alfred Wegener believe in continental
drift?
• 1. continents fit together like a puzzle
• 2. Fossils of the same species were found on
different continents
• 3. evidence of rocks and climatic conditions
were found on the same continents.
II. Breakup of Pangaea
• What did Wegener infer based on his
evidence?
• Millions of years ago there was one
supercontinent that over time slowly broke apart
III. Wegener’s Theory Rejected
• Why?
• Wegener could not conclude how or why the
continents moved.
• What discovery provided clues that Wegener
was right?
III. Mid-Ocean Ridge
• 1960’s underwater worldwide mountain chain
was discovered
• What happens at the mid-ocean ridge that
moves the continents?
• Sea-floor spreading
III. What is sea-floor spreading?
• As plates diverge magma rises up to form a
mid-ocean ridge. As more magma continues to
rise and harden it spreads the sea-floor apart
III. Evidence of Sea-floor Spreading
• How do we know sea-floor spreading is
happening? Seafloor Spreading Interactive
• Rock samples taken from the sea-floor show
that the oldest rocks are further from mid-ocean
ridges.
IV. Magnetic Reversals
• Throughout history Earth’s magnetic fields will switch.
Meaning the north pole goes to the south pole and
vice versa.
• Magnetic minerals in magma align with Earth’s
magnetic field. When the poles switch this creates
stripes or bands that can be seen on the sea-floor.