Continental drift Flashcards
who was Alfred Wegener
he was a German meteorologist
what inspired Alfred Wegener to create the theory of continental drift
that Africa and South America seemed to fit together like puzzle pieces
when was the theory of continental drift devoloped
1912
what is the theory of continental drift
the continents we have today were once joined together, but broke apart and drifted away from each other over the past 220 million years.
what was the supercontinent called
Pangaea
what are the five evidence that supports continental drift (in the order they were found in
- Shape of the continents
- Fossil evidence
- Rock evidence
- Glacial scars
- Coal deposits
def shape of continets
The continents seem to fit together like a jigsaw puzzle
def fossil evidence
Fossils of the same organisms have been found on different continents.
def rock evidence
Many mountain ranges that are separated by vast oceans contain rocks of the same type and age.
def glacial scars
Matching scars that have been caused by glaciers had been found on different continents, suggesting that they were once joined up around the South Pole.
def coal deposits
Coal deposits were formed millions of years ago in hot tropical areas around the equator.
However, in recent times, coal deposits have been found in polar regions such as Siberia.
why was wegener’s theory rejected
because he couldn’t explain where the enrgy came from
what was wegners theory on how the continents moved
the continental crust bulldozed it’s way through the oceanic crust
what was Wegener’s theory modified to in the 1960’s
that convection currents were involved
is plate tectonic theory still being revised
yes
