![]() continental drift), he was right for the wrong reasons, and the behavior of continents in where, how, and why they move, was completely different from what Wegener proposed. Thus, while Wegener was right about the existence of a phenomenon (i.e. It wasn't until many decades later that oceanic ridges were discovered, indicating the existence of convection within the mantle, that a way that continents could move would be found. They didn't believe Wegener because his theory made no useful predictions that could be tested, and would eventually turn out to be wrong.Īlthough Wegener did predict continental drift, his theory for why the continents move made no sense and is indeed false. Rather, entire tectonic plates with both continents and ocean crust on top of them move as whole units. What changed was the realization that it is not the continents themselves that move through the rest of the crust. They weren't aware of anything that could cause continents to move. ![]() Other scientists did not believe Alfred Wegener's theory of continental drift because they did not see any way that continents could move through the oceanic crust and the mantle, nor did they see evidence that this had happened. Plate tectonics is a theory which encompasses both the motion and mechanisms.Īnother interesting point is that Wegener was not the first to propose that the continents had previously been joined as a single supercontinent he even credited others who had similar ideas as early as 1848. The first refers only to the motion of the continents, with no suitable associated mechanism to cause that drift. Side note - many do not distinguish between continental drift and plate tectonics. Eventually, the ideas led to a new (and current) theory known as Plate Tectonics. Views on moving continents began to change in the 1950's as new measurements were made, such as geomagnetic patterns in the ocean floor and those providing evidence for sea floor spreading. There is a thorough answer to this already on ScienceLine.Įssentially, Wegener's proposal ( the theory of continental drift ) was rejected because (i) established experts firmly believed in another theory (that the continents and oceans were fixed in position), and (ii) Wegener did not provide a reasonable mechanism which would enable continents to move in the manner he claimed. It's only been for the past 60-70 years or so that Earth scientists have really started to understand how the different plates of the Earth's crust move around! So, although Wegener had the right idea, he couldn't explain HOW it had happened. This came together to ultimately take shape as the theory of plate tectonics. In the late 1960s (after the Great Alaska Earthquake), scientists began to understand how oceanic crust becomes destroyed (in subduction zones, where it gets 'recycled'. Then in the 1960s, people started to think that maybe new crust was being created at these mid-ocean ridges. He thought that continents 'plowed' through oceanic crust like a bulldozer - VERY wrong! Had he lived in a different time, he would have had better luck, because in the 1950's a scientist named Marie Tharp discovered the Mid-Oceanic ridge (this is literally the map that she drew BY HAND): Later when geologists realized that the Earth’s interior although solid actually behaves like a VERY VISCOUS FLUID did it become clear that the interior COULD MOVE at rates of a few inches per year.Īlthough continental drift was on the right track, Alfred Wegener lacked a MECHANISM by which the continents could move. ![]() Unlike air that moves around during to heating of ground by sun (and rotation of Earth) moving HUGE blocks of rocks was not understood. Why did other scientists not believe Alfred Wegener theory to be true?Īlfred Wegener was not able to provide a convincing explanation of how continents could move through the viscous Earth.
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