Alfred Wegener first proposed the theory of continental drift in the early 20th century. He noticed that the continents appeared to fit together and were once attached in a supercontinent called Pangaea. Wegener provided evidence from matching coastlines, fossil and rock formations, and paleoclimatic data to support his theory. However, he was unable to explain the mechanism of continental drift. Most geologists at the time rejected his theory due to the lack of a clear explanation for how and why the continents would move. It was not until the 1950s when the theory of plate tectonics was developed that Wegener's concept of continental drift became widely accepted.

1. CONTINENTAL
DRIFT THEORY

2. Describe the World

3. https://vimeo.com/14258924

4.  Abraham Ortelius, a Brabantian
cartographer and geographer and
known as the creator of the first
modern atlas (Theatrum Orbis
Terrarum or Theatre of the World).
Continents Drifting idea…
 Ortelius was the first to
underline the geometrical
similarity between the
coasts of America and
Europe-Africa and to
propose continental drift as
an explanation.

5. It refers to the movement of
the Earth’s continents relative
to each other, appearing to
“drift” across the ocean bed.
 This theory is publish in the book, “Origin of
Continents and Oceans” by Alfred Wegener
Continental Drift Theory

6.  It was fully developed by
Alfred Wegener (1880-1830),
a German meteorologist.
 According to Wegener,
the continents were
once joined together in a
one large landmass
called “supercontinent”
or “Pangaea”
Continental Drift Theory

8.  The Pangaea break-up led to an increase in
seaways and shorelines, which may have been
affected the diversification of terrestrial plants
and animals by creating several isolated
continental regions.
 During the final drifting of Pangaea, rapid
seafloor spreading caused a tremendous
released of carbon dioxide gas. Which led to
dramatic global warming that culminated about
92 million years ago.
Continental Drift Theory

10. A. Topographic Evidence
B. Fossil Correlation
C. Rock Formation
D. Paleoclimatic Evidence
Wegener’s Evidence

11.  Wegener noticed that the continents
seemed to fit together.
 The “good fit” suggested that just like
neighboring pieces of a jigsaw puzzle,
the continents were once connected in
a single supercontinent.
 He pieced together the map of Africa
and South America.
Wegener’s Evidence:
Topographic Evidence

12. Topographic Evidence

13. Fossils are traces and remains of
organism that lived in pre-historic times.
Wegener’s Evidence:
Fossil Correlation
 One of
Wegener’s
example is the
remains of
Mesosaurus.

14. Fossil Correlation

15.  Before Pangea broke
apart, similar layers of
rocks were formed in
Antarctica, Australia,
South America, Africa
and India. Glossopteris
fossils were found in the
rocks on each continent.
Wegener’s Evidence:
Fossil Correlation

16.  Rocks and fossils in
the continents located
in the southern
hemisphere exhibit
identical pattern
known as “Gondwana
Sequence”.
 These rocks were of
the same age and
type.
Wegener’s Evidence:
Rock Formation

17.  US
Appalachian
Mountains
are similar to
Greenland
and Europe
Wegener’s Evidence:
Rock Formation

19.  Wegener considered
as evidence the
glacial till deposits in
the northern and
southern latitudes.
 It was said that the
Earth’s climate has
not changed, instead
the positions of the
continents have
changed.
Wegener’s Evidence:
Paleoclimatic Evidence

20. Wegener’s Evidence:
Paleoclimatic Evidence
 The discovery of
fossils from tropical
plants in the form
of COAL DEPOSITS
in Antarctica.
 Possibly, Antarctica
used to be close to
the equator where
the climate is
warmer.

21. Paleoclimatic Evidence

22.  Glacial till & striations found in deserts
Wegener’s Evidence:
Paleoclimatic Evidence

23. Wegener’s Evidence:
Paleoclimatic Evidence
Franz Josef Glacier in New Zealand

24. So, what’s
wrong with
Wegener’s
Theory?
Most geologist did not believe Wegener.

25.  Wegener’s theory of continental drift was just
too weak for most geologists to accept. Even
though he believed the supercontinent that
broke up into different continents moved, he
did not have a clear explanation to how the
continents moved.
Wegener’s theory is rejected by some
because…
 Some of Wegener’s explanation clashed with ideas
that were widely accepted in the science
communities. He used similar fossils from different
continents to back up his theory of continental drift.
However, at that time, many scientists that had
observed similarities in fossils in places like South
America and Africa believed there were similar
fossils in different continents because of a land
bridge that were formed by two continents.

26. CONTINENTAL DRIFT THEORY
Imagine that you were with Alfred
Wegener to defend his Continental
Drift Theory. Help him answer the
following questions from the skeptic
scientists.
 How do continents drift from each
other?
 What causes them to drift apart?

27.  That Alfred Wegener’s original name for his proposed, ancient
continent was “Urkontinent”—ur meaning “first or original,”
and kontinent meaning “continent” in Wegener’s native
language, German. A more popular name for this huge ancient
landmass is Pangaea, which means “all lands” in Greek.
 That despite all these incredible evidences for
continental drift, Wegener was not able to see
his theory gain acceptance. He died in 1930
at the age of 50 from a probable heart failure
while on a scientific expedition in Greenland.
It was only in 1950s were new evidences
emerged to support his theory and develop a
new one.

28. Visit the following websites:
• https://www.slideshare.net/AbbieMahinay
• https://www.slideserve.com/devon/chapter-8-plate-tectonics
• https://www.youtube.com/watch?v=Wq9kLzm36h0
• https://www.youtube.com/watch?v=bQywDr-btz4