Comments on: Word of the day: Pangaea

By: Ben

Ben — Thu, 13 Oct 2011 14:57:43 +0000

Just thought you might be interested in my two cents. I am a Geography major and I have studied this phenomenon over my degree. There is a cycle called the Wilson cycle which occurs every 500 million years, which will see the continents go from a fully interconnected land mass on one side of the earth to a similar landmass on the opposite side due to continental drift. We are currently half way through a cycle, so our land masses are spread about the face of the earth, in 250 million years however, they will have reformed exactly opposite where pangaea once was. This cycle has probably occurred around 5/6 times in the history of our planet.

By: Roger Darlington

Roger Darlington — Mon, 29 Nov 2010 09:54:37 +0000

Not yet – but, if the weather in Britain stays this cold, may go there soon!

By: Philip

Philip — Mon, 29 Nov 2010 09:51:41 +0000

Roger, is this on your list of the countries you have visited? 😉

By: Nick

Nick — Sun, 28 Nov 2010 21:40:18 +0000

Good points, Roger.

As you say, it seems the “continental drift” (with no convincing mechanism) proposed by Wegener has been superseded by a “continental drift” (driven by plate tectonics), which might perhaps be renamed so that it doesn’t confuse non-geologists!

By: Roger Darlington

Roger Darlington — Sun, 28 Nov 2010 17:52:34 +0000

Good point, Nick. Perhaps I was overly influenced by the comment by Richard Dawkins in "The Greatest Show On Earth": "I must make it clear that his hypothesis [that of Alfred Wegener] of continental drift was significantly different from our modern theory of plate tectonics." The Wikipedia page on continental drift states: ".. it is now accepted that the continents do move across the Earth's surface – though more in a driven mode than the aimlessness suggested by 'drift' ". So I guess that the theory of continent movement has been confirmed but the notion of drift is now discredited and the mechanism for movement is now known to be plate tectonics.

By: Nick

Nick — Sat, 27 Nov 2010 21:28:21 +0000

I don't think plate tectonics has replaced continental drift; rather, plate tectonics is one of the mechanisms underlying (pun intended!) continental drift. See Plate Tectonics and Continental Drift.