The Theory of Continental Drift

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Transcript The Theory of Continental Drift

The Theory of Continental
Drift
Alfred Wegener
1912
Proponent of the
continental drift
theory/hypothesis
German
meteorologist
Continental Drift Theory
• The continental drift hypothesiscontinents have moved slowly to their
current locations
• All continents were once connected as
one large landmass called “Pangaea”
• The land mass broke apart, and the
continents drifted to their present positions
Evidence to Support the Theory
“Puzzle Pieces”
• Puzzle-like fit of the
continents
• Continents look like
they could be part of
a giant jigsaw puzzle
Distribution of Fossils
• Similar fossils have
been found on
different continents
• Remains of warmweather plants in
Arctic areas and
glacial deposits in
tropical areas suggest
that continents have
moved
Sequence of Rocks
• Similar rock
structures are found
on different
continents.
• Same rock patterns
found in South
America, India, Africa,
Antarctica and
Australia
Ancient Climates
• Tropical plant remains
(coal deposits) found
in Antarctica
• Glaciation in Africa,
South America, India,
and Australia during
the same time
Problems With The Theory
• No mechanism for movement of
continents
• Wind and currents could possibly move
fossils
• Theory was not accepted by scientists
• At first, continental drift was not accepted
because no one could explain how or why
continents had moved
1930
Wegener leaves
for Greenland to
find evidence for
his hypothesis.
He is never seen
again
The last photo him
His theory is
hotly debated for
the next 30 years
Continental Drift Theory
*The continental drift hypothesis- continents
have moved slowly to their current locations
*All continents were once connected as one
large landmass called “Pangaea”
*The land mass broke apart, and the continents
drifted to their present positions