The Pangaea Theory - River Dell Regional School District

advertisement
The Pangaea Theory
The Pangaea theory is one that states that all present continents were once together and
collectively known as a 'supercontinent' called a Pangaea. The word 'Pangaea' means 'all lands' in
Greek, accurately defining the way the continents were 200 millions years ago before it split up.
These split-up pieces drifted slowly apart and became the way they are today. Even until now,
the shape of the Earth surface is still changing, and it will be forever, as long as the mantle
underneath the Earth's crust gets heated and convection currents in the magma keeps dragging
the plates.
The Pangaea theory was treated with much skepticsm when it was first raised. But since then,
there have been much evidence to support this theory.
Evidence Of Plate Tectonics
It has been proven that the Earth's present continents were once together as a Pangaea as seen
from:




Continental Coastlines Appearing To Fit Together
One prominent example of continental coastline fitting together is to fit the coastline of the West
Coast of Africa with the coastline East Coast of South America. It can be seen that they fit well,
like pieces of a jigsaw puzzle. This helps to prove that these continents were once joined together
as one whole Pangaea and broke away to form these two land masses now
Fossil Distribution
Matching fossil of reptiles have been found in Africa and South America, further proving that
these two continents were actually so close to each other or even joined, that reptiles could travel
to and fro between them easily. Identical fossil ferns have also been found in all southern
continents, and also embedded in the same layer sequence, suggesting the proximity the southern
continents were in millions of years ago that allowed the growing of these ferns in the same
climate and soil.
Distinctive Rock Strata
Geologists have discovered that the geological structures of the rocks in South West Africa and
South East Brazil were distinctively identical, and the age of the rocks at these two areas was the
same. This distinctive rock strata shared by the two land masses suggests that these two areas
were once joined together.
Coal Distribution
Coal can be found underneath the cold and dry Antarctic ice cap, though coal can only form in
warm and wet conditions. This could mean that Antarctica was once together with the other
continents as part of the Pangaea, and was once in a warm and humid region. Coal was formed
before Antarctica drifted away to its present cold and dry climate. That is why the coal can be
found buried under the thick layer of ice and snow.
Download