Aim: How have the continents
changed over time?
Topic: Dynamic Earth
Main Idea: Plate Tectonics & Continental Drift
1) What is plate tectonics?

Plate
tectonics is
the study
of how
crustal
plates
move and
interact.
2) What evidence is there for past
crustal movement?
What can you tell about the history of
crustal movement in the area of the Grand
Canyon?
Let’s Review!!
Collaborate
with the
person next to you to
agree on an answer
for these 3 questions.
Think About It:
If Pangaea reforms while
humans are still present on
Earth how would it affect
civilization (economy, political
leadership, travel, foreign
relations, etc…)?
Who was Alfred L. Wegener?

He proposed that
the earth was a
single
supercontinent
(Pangaea) that
separated over
time.
What evidence did he have for his
theory?




N. and S. America fit
together with Africa
and Europe
The structure of the
rocks matched
perfectly with the coast
of Africa and Europe
Tropical fossils were
found in cold climates
along the coast
Evidence of glaciation
in S. America, S. Africa,
India & S. Australia
What was wrong with Wegener’s
theory?
Not all pieces
fit perfectly
 At the time it
was thought
that the earth
did not have
layers
 Wegener didn’t
know what
made them
move

How will the earth change in the future?
Summary
Find the appropriate page in your reference
tables and answer the following questions
1) In which direction has North America
moved? _________________
2) When did the Atlantic Ocean begin to
form? ______________________
What do you notice in each of these
three pictures?
What happened in this one?
What is a fault?

A fault is a crack that runs through strata
and displaces them.
What are the three types of faults?
The three faults
are:
Normal
(Tension)
Reverse
(Compression)
Strike-slip
(Shear)

What is the movement associated
with normal and reverse faults?
Normal: the footwall moves up (FUN)
 Reverse: the footwall moves down (FDR)

What is the movement associated
with a transform fault?

The plates slide past each other. If they
get stuck pressure is built up, but once the
rocks snap it creates an earthquake.