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Abraham Ortelius
In the year 1596 cartographer Abraham Ortelius noted that the coastlines of Africa and South America appeared to fit together, compelling him to propose that the continents had once been joined but were pulled apart by "earthquakes and floods." And yet, the theory of plate tectonics represents a fairly young science. -
Eduard Suess
Austrian geologist Eduard Suess proposed that large ancient continents had been composed of several of the present-day smaller ones. According to this hypothesis, portions of a single enormous southern continent—Gondwanaland—foundered to create the Atlantic and Indian oceans. Such sunken lands, along with vanished land bridges, were frequently invoked in the late 1800s to explain sediment sources apparently present in the ocean and to account for floral and faunal connections between continents -
PALEOLONTOLOGICAL EVIDENCE
Certain fossils found on both sides of the Atlantic have a striking similarity that is difficult to explain if the continents were not once connected as one. Lystrosaurus and Cynognathus, two land-dwelling reptiles that lived during the Triassic Period, have been discovered on various continents, and their fossils are so numerous that they account for a large
percentage of the bones recovered at some fossil beds. -
Antonio Snider-Pellegrini
In 1858, geographer Antonio Snider-Pellegrini made these two maps showing his version of how the American and African continents may once have fit together, then later separated. Left: The formerly joined continents before their separation. Right: The continents after the separation. -
ISOSTASY, Clarence Edward Dutton
Also known as Contracting Earth Concept was further explained when American seismologist and geologist Clarence Edward Dutton, proposed the term "ISOSTASY". This states that wherever equilibrium exists on the Earth's surface, equal mass must underlie equal surface areas. MEANING: a great continent mass must be formed of lighter materials than that supposed to constitute the ocean floor. -
Wegener’s Initial Hypothesis
In 1910, Wegener first thought of the concept of continental drift when he was studying the map of the world. He saw the direct impression produced by the congruence of the coastlines on both sides of the Atlantic. However, Wegener did not pay too much attention to this concept at this time as he thought it was irrational. Source: Modified excerpt from Alfred Wegener, The Origin of the Continents and Oceans -
Supporting Evidence
In 1911, Wegener read a report about paleontological (a branch of science regarding fossil plants and animals) evidence for a land bridge that once joined Africa and Brazil. Thus, he used an interdisciplinary approach and found information in the fields of geology and paleontology that challenged the idea that continents never changed. Source: Modified excerpt from Alfred Wegener, The Origin of the Continents and Oceans. -
CONTINENTAL DRIFT THEORY, Alfred Wegener
Alfred Wegener, proposed the CONTINENTAL DRIFT THEORY in his book, The Origins of Continents and Ocean in 1915. He expanded the theory and presented evidence that Pangaea (All Earth) had existed during the Permian period. -
EVIDENCES VIA PALEOMAGNETISM
There was no proof to support Wegener's theory until the 1950s, when the field of paleomagnetism was developed. It proved that the continents were once located in different positions due to the uncovering of particular minerals that form in alignment with Earth’s polarity. Instead of pointing north or south, they pointed in easterly and westerly directions. Alas, scientists were still in denial as there was yet to be nothing solid that supported Wegener. -
SEAFLOOR SPREADING, Harry Hess
Harry Hess, is a U.S. Navy Officer and professor who propose and wrote a paper on a process that he called “Seafloor Spreading”. He found that liquefied rock leaks through from the Earth's centre, expands to form a new ocean floor and then goes back into the Earth's centre via oceanic trenches (subduction). However, like Wegener, Hess was confronted with controversy as there wasn't a lot of data on ocean floors. -
The Vine-Matthews-Morley Hypothesis
In 1963, geophysicist Fred Vine, and geologists Lawrence Morley and Drummond Matthews proposed a new theory that supported Wegener's one of continental drift. They thought that if oceanic floor is continually being newly created, the rocks on the ocean floor should give an indication to past reversals of the magnetic field. -
Henry Frankel - Acceptance of Continental Drift
Finally, Wegener's hypothesis of continental drift was accepted. According to Henry Frankel, geologists, palaeoclimatologists and biogeographers used the idea of continental drift to explain the similar way plate tectonics act. The plate tectonics theory has yet to be dismissed as supporting evidence is more abundant, unlike when Wegener was structuring his theory. Modified from Henry Frankel, “From Continental Drift to Plate Tectonics.” -
WORLD WIDE ACCEPTANCE
Today, in 2016, the concept of continental drift is very much a reality. There is an abundance of evidence conducted by scientists who use an interdisciplinary approach to solidify facts about the Earth's future. From 1910, when Wegener first pitched his unsupported hypothesis to today, much has changed in terms of acceptance - continental drift is known to be real. Wegener is now completely recognised to be the first one who noted continental drift.