8 Nov 2013

The Man Who Made the Earth Move

Claire Eamer

Just about this time of year, back in 1930, one of the most famous figures in modern geology lay down to die on the snow-covered ice cap of Greenland. On November 1, Alfred Wegener celebrated his 50th birthday with friends at a tiny, temporary meteorological station on the glacier. The next day, he and one companion - a young Greenlander named Rasmus Villumsen - hitched up the sled dogs and headed back to the coast to rejoin their main party.

They never made it. In the spring, his friends found Wegener's body, laid out carefully on a reindeer hide and buried in snow. Villumsen was never found.

Wegener explaining continental drift - as depicted by
illustrator Sa Boothroyd.
From Before the World Was Ready: Stories of Daring Genius in Science
Unsung Hero

Today, Wegener is a celebrated hero in the world of geology, but that wasn't true when he died. Then he was a meteorologist and polar scientist with a weird idea that drove many geologists into a frenzy. The continents, Wegener said, weren't stuck in place. Instead, they moved - ever so slowly - around the globe, breaking apart to create oceans and coming together to create mountain ranges. He called his theory Continental Drift.

Most geologists hated the idea. They couldn't see how continents could move (and Wegener couldn't explain that either), and they were deeply offended that a mere meteorologist would stick his nose into their science. By the time of his death, Wegener had been amassing evidence and arguing his theory for 20 years without convincing them.

It would be another 30 years after Wegener's death before the geological world took him seriously. What it took was the discovery of a mechanism that explained the movement of the continents.

Marie and the Ocean Floor

Mapping the sea floor with sound waves.
Illustration by Sa Boothroyd, from
Before the World Was Ready (Annick Press 2013)
One of the first to recognize the mechanism was an American geologist, Marie Tharp. In 1952, an American survey ship was trundling up and down the Atlantic Ocean, using new technology involving sound waves to study the ocean floor. Back in the lab, Tharp was drawing ocean-bottom maps based on the ship's data.

She spotted a formation more familiar from land - a rift valley, created when two bits of earth's crust pull apart. And it meant, she realized, that the ocean bottom was spreading, getting wider. That meant that the continents on either side were moving apart, just as Wegener had said.

It took months before Tharp could convince her colleagues that the ocean really was growing wider. Even then, most geologists still considered Wegener sadly mistaken - at best.

The Canadian Connection

One of the scientists who took the evidence of ocean spreading a bit more seriously was Canadian geologist and physicist John Tuzo Wilson. He later said it took him almost a decade to accept the idea that the continents move, but once he did, there was no stopping him.

Tuzo Wilson realized that Earth's surface is made up of massive plates that move around, pushed and pulled by the forces in the planet's molten core. He pioneered the study of what is now called plate tectonics in a now-classic 1965 journal article called  "A New Class of Faults and their Bearing on Continental Drift." It was the vindication and elaboration of Wegener's much-despised theory from 35 years earlier.

And if Wegener hadn't died on that remote icefield in 1930, he might still have been around - a hale and hearty 85-year-old - to enjoy the triumph.

Want to Know More?

The story of Alfred Wegener and Marie Tharp and a few others is in my new book, Before the World Was Ready: Stories of Daring Genius in Science (Annick Press 2013).

There's plenty of information about Wegener on the Internet. Here's a good site, with links about different aspects of plate tectonics. And here's a lovely bio of Marie Tharp, in her own words.

John Tuzo Wilson was a science communicator as well as a scientist. He spent more than a decade as director general of the Ontario Science Centre in Toronto. Here's a short biography of J. Tuzo Wilson (as he was usually called), and here's a longer one.

1 comment:

Jan Thornhill said...

Lordy - so this is where I was recently reading about continental drift & Wegener - that's hilarious!

So his name came up in my hair ice research - all fine & good - but it wasn't until I was about to post that I realized the German polar institute I've linked to is named after him for crying out loud. Something's in the air, and it don't cost nuthin'! What fun!