Subscribe
Subscribe
MY AMERICAN SCIENTIST
LOG IN! REGISTER!
SEARCH
 
Logo IMG
HOME > My Amsci > Restricted Access

How Do Supercontinents Assemble?



Restricted Access The content you've requested is available without charge only to active Sigma Xi members and American Scientist subscribers.


If you are an active member or an individual subscriber, please log in now in order to access this article.

If you are not a member or individual subscriber, you can:



Abstract:

Over the past 3 billion years, at least six supercontinents have assembled and split apart in what some earth scientists refer to as the supercontinent cycle. About that much there is general agreement; just how this process works, however, has been a source of considerable controversy. One camp would have the continents spread apart and reunite much like an accordion. Another thinks that land masses break up and circumnavigate the globe before getting back together again. The resolution lies in establishing the crystallization dates of oceanic crust that was generated or consumed during continental movement, but "seeing" back further than one cycle has proved difficult. The authors have used a unique radioactive-isotope ratio to determine that both tectonic processes have likely been at play.


Connect With Us:

Facebook Icon Sm Twitter Icon Google+ Icon Pinterest Icon RSS Feed

Subscribe to Free eNewsletters!

  • American Scientist Update

  • An early peek at each new issue, with descriptions of feature articles, columns, and more. Every other issue contains links to everything in the latest issue's table of contents.

  • Scientists' Nightstand

  • News of book reviews published in American Scientist and around the web, as well as other noteworthy happenings in the world of science books.

    To sign up for automatic emails of the American Scientist Update and Scientists' Nightstand issues, create an online profile, then sign up in the My AmSci area.


Read Past Issues on JSTOR

JSTOR, the online academic archive, contains complete back issues of American Scientist from 1913 (known then as the Sigma Xi Quarterly) through 2005.

The table of contents for each issue is freely available to all users; those with institutional access can read each complete issue.

View the full collection here.


RSS Feed Subscription

Receive notification when new content is posted from the entire website, or choose from the customized feeds available.


Write for American Scientist

Review our submission guidelines.


Subscribe to American Scientist