Skip Navigation
Regional News
This road in Iceland runs down the fault line where the Eurasian continental plate meet the North American continental plate. Photo: <a href="http://www.flickr.com/photos/watz/519498840/">Marius Watz</a>, Creative Commons, some rights reserved
This road in Iceland runs down the fault line where the Eurasian continental plate meet the North American continental plate. Photo: Marius Watz, Creative Commons, some rights reserved

Natural Selections: Continental Drift

Listen to this story
The theory of continental drift--the idea that the continents are islands of rock adrift on the earth's molten core--first gained acceptance in the 1960s. Dr. Curt Stager and Martha Foley talk about the consequences of their extreme slow motion collisions--earthquakes and volcanic eruptions.

Hear this

Download audio

Share this


Explore this

Story location

News near this location

Synopsis of this Natural Selections conversation:

Not so long ago, the idea of continental drift was rejected by geologists. Although there has been strong evidence for it, it wasn't widely accepted until the 1960s.

"When you look at these maps you can see that in the middle of the Atlantic, there is big ridge with cracks and a big zipper running right up the middle of it," says Dr. Curt Stager. "This is where molten rock comes out from the depths of the earth, forms new ocean crust, and pushes the old aside."

Stager says, "If stuff is coming up it has to be going down somewhere else. The most likely place you will see this is where you have a continent on top of the heavier ocean stuff." On the edges of the Pacific, ocean crust is sliding underneath the continents. The sliding causes earthquakes and the re-melting and cracking of crust cause volcano formations, such as the Ring of Fire.

If you go to a Pacific island, you will find that the further it is from an ocean spreading zone, the older it is. In the American Northwest, some islands used to be on the ocean floor. As the crust slides under the continent, the Islands are scraped off onto the shore.

Visitor comments

on:

NCPR is supported by:

This is a Visitor-Supported website.