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First Time the Continent Drift Theory Was Presented
In 1596, Abraham Ortelius noticed that the shapes of the coastlines seemed to fit together, like a puzzle. So he theorized that one time, all the continents where joined together and that America had separated itself form Africa and Europe. -
The Discovery of Pangaea
in 1912, Alfred Wegener had a hypothesis that about 300 million years ago, all the continents had been joined into a supercontinent he called Pangea. This hypothesis is similar to Ortelius. He proved this theory by using fossil clues, climate clues, and rock clues. But even with evidence, the science community did not accept his findings as Wegener's theory had flaws. This included the failure to answer the mechanisms and forces in order for the continents to go through the ocean. -
Wegener Publishes Drift Theory
In 1915 the first edition of The Origin of Continents and Oceans, a book outlining Wegener's theory, was published; expanded editions were published in 1920, 1922, and 1929. -
Magma is the Driving Force for Continental Drift?
In 1929, Arthur Holmes came up with the idea that the convection in the mantle is the driving force in which continents move.He suggested that convection in the mantle is the force driving continental drift. . He proposed convection currents move through the mantle the same way heated air circulates through a room. This theory was subsided but after WW2 that scientists produce the hard evidence to support Holmes’s fundamental concept -
Seafloor Speading Discovery
In 1960 Harry H. Hess developed the idea that oceanic crust forms along mid-ocean ridges. This is called seafloor spreading. He supported his theory was that the seafloor was warmer near the Mid-Atlantic Ridge. This was actually heated from the magma underneath it. Other evidence is that subduction gets rid of the seafloor, but it is not slowly disappearing. Also, magnetic polarity alternates between normal and reversed. The science community accepted the theory because of evidence and logic. -
Hotspots in the Mantle.
in 1963, John Tuzo-Wilson proposed that plates might move over fixed ‘hotspots’ in the mantle, forming volcanic island chains.Evidence supporting this theory is pretty much every single chain island, famously including Hawaii. This answered the question why active volcanoes are found many thousands of kilometers from the nearest plate boundary, so the science community agreed to this theory. -
Frederick J. Vine, Drummond H. Matthews, and Laurence W. Morley's Theory
In 1963, Frederick Vine, Drummond Matthews, and Laurence Morley suggested that new crust would have a magnetization aligned with Earth’s geomagnetic field. Evidence for this is that magnetite from the mantle rises up through mid-ocean ridges and cools, it saves a record of the polarity of the Earth’s magnetic field. Magnetite in the basalts is strongly magnetic and aligns with the magnetic field when it cools. This was highly accepted because this only adds on to Hess's idea. -
The Discovery of Transform Faults.
In discovered with the idea of a third type of plate boundary - transform faults also known as a conservative plate boundary. They allowed for plates to slide past each other without any oceanic crust being created or destroyed. Evidence for this is the San Andreas Fault between the North American and Pacific plates. This was thought as revolutionary and was widely accepted because this was thought to be the missing piece of the puzzle of the plate tectonic theory.
