Download Unit 3 Physical Oceanography

Unit 3
Physical Oceanography
UEQ: What geological processes are
responsible for the physical features of
the Earth.
Concept 2: Continental Drift and Plate
Tectonics
• LEQ’s
1. What is the Continental Drift Theory?
2. How did scientists develop the Continental Drift
theory?
3. What is the theory of Plate Tectonics?
4. How does Plate Tectonics relate to the
Continental Drift Theory?
LEQ1: What is the Continental Drift
Theory?
• In 1912 a German scientist named Alfred
Wegener proposed that all the known
continents were once one large continent
called Pangaea surrounded by one large sea
called Panthalassa.
– These words come from Greek words.
• Gaea is the Greek Goddess of Earth
• Thalassa means sea
• Pan means all
PB
• What does Pangaea mean in Greek?
• What does Panthalassa mean in Greek?
LEQ1: What is the Continental Drift
Theory?
• Wegener looked at maps and saw that the
continents seemed to fit together like puzzle
pieces.
– He proposed that the continents were drifting apart
by floating on the mantle and had been drifting
apart for 200 million years.
– 100 Greatest Discoveries: Continental Drift
LEQ2: How did scientists develop the
Continental Drift Theory?
• Evidence to support Continental Drift:
– Fossils of the same animals and plants have been found
on continents that are not currently connected but
would have been in Pangaea.
LEQ2: How did scientists develop the
Continental Drift Theory?
– Rock Layers on one continent line up with rock layers on
other continents that would have been connected in
Pangaea.
LEQ2: How did scientists develop the
Continental Drift Theory?
– Mountain Ranges that are the same size, age, and rock
types spread across more than one continent without
continuing under the ocean.
LEQ2: How did scientists develop the
Continental Drift Theory?
– Glacier evidence is found on multiple continents, some
of which are located in regions that the glaciers should
not have reached, unless the glacier happened on
Pangaea.
Rally Robin Write
• List the 5 pieces of evidence for the
Continental Drift theory.
– Who ever is younger A or B begins.
• Once you have listed all five pieces of
evidence, write down whether you feel this is
enough evidence to support this theory and
justify your answer.
– Share with your partner, this time whomever is
older goes first.
LEQ2: How did scientists develop the
Continental Drift Theory?
• Even with all of this evidence to show that
Pangaea had indeed existed, Wegener could
not fully explain how the continents were
moving.
• Without an explanation for how Continental
Drift was occurring, the scientific community
rejected this theory.
LEQ 3: What is the theory of Plate
Tectonics?
• During the same time period as Wegener, new
technology was being created that allowed
scientists to “see” the sea floor.
– SOund Navigating And Ranging = SONAR
– This allowed maps to be made of the sea floor.
• Technology continued to improve through
World War II.
LEQ 3: What is the theory of Plate
Tectonics?
• In 1960 two scientists used the SONAR data
and were able to determine that the sea floor
is constantly spreading in some regions and
being recycled in others.
• 100 greatest Discoveries: Sea Floor Spreading
Yay or Nay
• A’s: You believe that the idea of sea floor
spreading is important to the Continental Drift
theory. State your case and justify it to B.
• B’s: You think that the idea of sea floor
spreading has nothing to do what so ever with
the Continental Drift theory. Argue your case
in response to what A stated.
• A’s: One more chance to argue your case
against B.
LEQ 3: What is the theory of Plate
Tectonics?
• The theories of Continental drift and the
information of Sea Floor Spreading were combined
into the theory of Plate Tectonics.
– The theory of Plate Tectonics states that Earth’s crust is
split in many plates that flow along the mantle. These
plates can move in three ways:
• Towards each other = converging
• Away from each other = diverging
• Sliding past each other = transforming
– There are 52 total plates, 14 major and 38 minor
Diverging
Converging
Transforming
Bill Nye Plate Tectonics Demonstration