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Wegener believed a land bridge was impossible. It would have left telltale signs on the
ocean floor and would create gravitational anomalies that did not exist. In 1912, he decided
to build a body of evidence from a variety of fields to prove that the continents had once
been joined.
He used the extensive fieldwork of Eduard Suess to provide most of his geological
data. Suess discovered that, in place after place, rocks on coasts that faced each other across
the oceans often matched exactly.
Wegener poured through the findings of hundreds of geologic surveys to show that the
rock formations, mix of rock kinds, and rock stratification on the two continents (South
America and Africa) matched up and down the coastline. He found formations known as
pipes (associated with diamonds) on both sides of the south Atlantic, exactly opposite each
other.
He also collected records of past and present plant communities on both sides of the
Atlantic and mapped them to show how they matched up and down the coast.
The only explanation Wegener could offer for these similarities was that South America and Africa u