Transcript Alfred Wegener

Alfred Wegener
1880
1930
Continental Drift
Becky Dobosy May 2005
Alfred Wegener
•Born in Berlin,
Germany, Nov. 1,
1880.
• Meteorologist and
geophysicist.
Alfred Wegener
•Discovered
continental drift
•Originated
theory of Pangaea
•Died Nov. 1,
1930
Alfred’s Theory
Wegener believed the earth was
made up of moving plates.
Originally, all the continents were
combined into one called Pangaea.
Early Pangaea
The animals and plants could disperse
with all the future continents together.
The one ocean was the Panthalasia.
Later Pangaea
Pangaea broke into Lausasia and
Gondwanaland and trapped animals on
one or the other.
Today
This is the current map of our
world after about 200 million years
of continental drift.
The Future?
Some scientists’ view of the
continents in a million years.
Acceptance of the Theory
Wegener’s theory wasn’t accepted
until the discovery of sea floor spreading.
The spreading
is caused by
liquid mantle
coming up and
cooling to form
new ground.
This creates
and ocean
trenches and
ridges, like the
Mid-Atlantic
Ridge.
It also causes the Atlantic Ocean to
expand and the Pacific to shrink.
Fossil Proof
The same fossils can be found on
different continents spread miles apart.
When the continents are in Pangaea’s
shape,the fossil areas match up.
Lithocology Proof
Lithocology is the study of the
distribution of major geological
bodies such as mountains and seas.
Mountains
ranges and
rock bases
match with
the other
Pangaea
continents
where they
broke off.
Palemagnetism Proof
North Pole
Magnetic
attraction
Earth
Particles in cooling rocks point to the
north pole due to the Earth’s magnetism.
Palemagnetism cont.
After drifting, the rock’s magnetic
particles no longer point North.
Palemagnetism cont.
From the direction the particles are pointing,
we can tell where the rock originally was in
Pangaea.
Tectonic Plates
There are 30 plates that make up our Earth.
Divergent Boundaries
•Usually on
ocean floor
•Creates sea
floor
spreading
•Make ocean
ridges and
earthquakes
Divergent
Examples
Great Rift Valley land fault
Mid-Atlantic
Ridge - ocean
fault
Convergent Boundaries
•Edge of plate sinks
under neighbor
•Called subduction
•Makes biggest
earthquakes
Examples
Himalayas - land
plates combining
and growing
California
Coast - land
plate growing
Chile Coast shrinking from
subduction
Transforming Boundaries
•Plates slide
horizontally
•Rough
edges rub
together
•Cause frequent
earthquakes
Transforming Fault
Examples
Bam
Fault
in
Iran
San Andreas
Fault in
Cailifornia
Earth Quakes
Earth quakes (red) occur on the fault
lines (yellow) of certain plates.
Folded Mountains
•Wavy layers
where plates
collide
•Rock piles up
•Examples:
Himalayas, Alps,
Rockys, Andes
Fault Block Mountains
•Plates pull apart
Grand Tetons
•One side
of fault
goes up,
the other
down
•Example:
Sierra
Nevadas
Volcanic Mountains
•On edges on hot
spots of plates
Before
Examples:
Mt
Etna
•Hawaii - volcanic islands
•Yellowstone - underground
volcano
After
Me
Hey, my name is
Becky. I live with
my parents and
have two older
sisters.
I also have a guinea pig
named Chloe. I love the
mountains and being
outside.
Bibliography
“Alfred Wegener.” Scientists: The Lives
and Works. 1996 ed.
George, Linda. Plate Tectonics. San Diego:
Kid Haven Press, 2003.
“Plate Tectonics.” World Book. 2003 ed.
A Lesson in Plate Tectonics. 2005. Extreme
Science. 2 May, 2005. <http://extremesc
ience.com/PlateTectonicsmap.htm>