Continental drift theory

Continental drift theory

2. The Continental Drift, is a theory
that proposed that all of the
continents were once a single land
mass known as PANGAEA. This
theory was proposed by ALFRED
LOTHAR WEGENER

3. ALFRED WEGENER
- A German Scientist, in the year
of 1912 who proposed Continental
Drift Theory.

5. Evidence
Although, Wegener didn't have any
proof, there was evidence discovered
supporting the theory by several
scientists. Unfortunately, the evidence
was gathered after Wegner passed
away. There are approximately five
pieces of evidence that support the
theory of the Continental Drift.

6. PANGAEA EVIDENCE
1.Jig saw puzzle of continents

7. PANGAEA EVIDENCE
2. The similar ancient animals and
plant fossils, found on the edges of
various continents.
fossil of a
GlossopterisFossil of a
Mesosaur
fossil of a
Cynognathus
Fossil of a
Lystrosaurus

8. PANGAEA EVIDENCE
This is a map of Pangaea, showing the
continents connected and showing the
matching fossils of plants and animals.

9. PANGAEA EVIDENCE
3. Identical rock sequences and
age.
- Basically meaning, various
countries have identical rock
sequences. For Example, South
America and Africa have identical
rock sequences, because they were
joined when Pangaea existed.

10. PANGAEA EVIDENCE
4. North America and Europe
having the same mountain
ranges.
- there have been mountain ranges
found in North America and
Europe that are identical, proving
the theory.

11. PANGAEA EVIDENCE
5. The climatic conditions.
- There have been glacial deposits
founded in the tropics and coal founded
in Antarctica. This supports the theory
of the Continental Drift, because coal
originates from tropical plants, which
can only be founded in the tropics.
Additionally glacial deposits can only
come from Antarctica, proving the
theory.

12. PANGAEA EVIDENCE
This photo shows the glacial deposits
founded in various continents

13. Although, this is the theory believed by many
scientists today, many were skeptical about
Wegener's theory during his period of time.
Many were skeptical, because he couldn't prove
the theory of the Continental Drift, although he
proposed the idea.
Furthermore, he couldn't prove the movement of
the continents. However, after Wegner passed
away, it was proven that the movement of the
continents, resulted from the motion of crustal
plates.

14. Seafloor Spreading
provided insight to the
mechanism for how the
continents moved.
The magma which pushes
up at the mid-ocean ridge
provides the new land
pushing the plates, and the
subduction zones gobble
up the land on the other
side of the plates.
The mechanism was
convection currents!

15. Thirteen plate on the world

17. Pangaea about 200 million years ago, before it began
breaking up. The southern portion of Pangaea
GONDWANA , and the northern portion LAURASIA.

22. As the seafloor spreads apart at a mid-ocean ridge,
new seafloor is created.

23. Plate tectonic explain
Earthquakes
Mountains
volcanoes

24. Earthquakes and volcanoes occur mostly along or near Earthquakes and volcanoes occur mostly along or near
trenches and mid-ocean ridges...trenches and mid-ocean ridges...

30. Continents look like
they could be part of
a giant jigsaw puzzle

31. Distribution of fossils of several organisms
supported The theory that the continents were
once joined together

32. Francis Bacon (1561-1626) first noted
how coasts of Africa and South
America fit.

33. Mesosaurus, a fresh water reptile that
couldn’t swim across the open sea

34. Same rock patterns found in South America, India,
Africa, Antarctica and Australia

35. Mountains in South America and
Antarctica are believed to have
formed as part of the same mountain
chain.

36. Tropical plant remains (coal deposits) found in
Antarctica
Glaciations in Africa, South America, India, and
Australia during the same time

37. Deposits found in
Antarctica.
Coal requires a warm,
lush climate ===>
What’s Antarctica like
today? ===>

39. Fossils of Glossopteris
are found in Permian
rocks of South Africa,
India, Australia,
South America, and
Antarctica—all
regions that were
once part of
Gondwanaland.

40. •No mechanism for movement of continents
•Wind and currents could possibly move
fossils
•Theory was not accepted by scientists