Alfred Wegener gathered a pile of evidences in trying to justify or prove the drifting or movement of continents. These evidences include the following.
Visual fit (jig saw fit).
The first proof which shows that continents are constantly moving away from each other is the visual fit of continental coastlines with one another. The eastern coast of south America and west Africa are so related in shape that it seems obvious that the two continents once fitted together like a piece of jig saw but just separated.
Matching geology.
The same geological rock structure exists on both sides of the continents for instance rocks between West Africa and South America have a got a convincing matching geology like along the parts of North Eastern Brazilian coast, South Eastern Nigeria and Cameroon and Accra in West Africa and Sao Luis in Brazil. This shows that they were part of the same landmass before breaking up.
similar geology.
Oil beds of brazil are similar to those of Angola.
Matching organic belts.
This is an alignment of belts of fold mountains. This is because the fold ranges of Falkland of Argentina are similar in age and structure to those of south west cape of south Africa. This clearly implies that the two continents were once together.
Lateritic evidence.
Lateritic soils form under tropical climates (high rainfall and high temperatures). However, these lateritic soils are unbelievably found in the temperate regions of north America, Britain and parts of Russia. This is an evidence that by the time these laterites were formed, such areas were in the tropics and hence have since then drifted into the temperate regions.
Coral evidence.
Like lateritic soils, coral reefs only grow in tropical waters. Coral polyps only survive in water whose temperatures are as high as 200C. It’s amazing however to find these coral reefs in the temperate areas of Greenland, oxford England and other temperate areas. So this is a clear evidence that coral reefs formed in tropical areas with high temperatures but just drifted away from the tropics to the temperate regions.
Saul salt evaporates.
Like lateritic soils and coral reefs, salt evaporates only form in hot climates. To the amusement of most geographers however, these salt evaporates are found in large quantities in areas like north America, Britain and on the foothills of Ural Mountains of Russia. These salt evaporates are believed to have been in the tropics and when drifting took place, salt evaporates went to such areas.
Similarity in flora and fauna.
The Brazilian coast of south America and the coast of west Africa have animal and plant life which are similar particularly with forests in Congo and Gabon i.e. similar plant life and tree species and animal life.
Occurrence of similar fossils.
Evidences from fossils are good indicators of continental drifting. Fossils’ structures of the same land animals and plants have been found in all southern continents in rocks dating about 250 million years ago for example a fern like plant and animal resembling a crocodile, their remains have been found in India, south America, Australia and Africa. This indicates that before drifting, these continents were once together as one block.
The proximity or nearness of the continental blocks near the north pole than in the south pole is a clear evidence that continents are still moving northwards.
The extension of Sahara Desert southwards indicates that Africa as a plate is still moving northwards.
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