Department of Energy Argonne National Laboratory Office of Science NEWTON's Homepage NEWTON's Homepage
NEWTON, Ask A Scientist!
NEWTON Home Page NEWTON Teachers Visit Our Archives Ask A Question How To Ask A Question Question of the Week Our Expert Scientists Volunteer at NEWTON! Frequently Asked Questions Referencing NEWTON About NEWTON About Ask A Scientist Education At Argonne Super Continent
Name: groovey
Status: N/A
Age: N/A
Location: N/A
Country: N/A
Date: 1999 - 2000

My 6th graders are about to start their inter stellar/planetary studies. Subject: Land mass distribution at the beginning If the Earth formed out of the primordial gas cloud, one would expect that the continents would be dispersed in a balanced configuration as the Earth cooled. However modern theory places them together in a large land mass or "super continent, seemingly in an out of balanced state. How did this happen?

Wonderful question! I'm going to quote from two texts ["Pangaea" is the name given to the "supercontinent" which, it is believed, broke apart, over 200 million years ago, into pieces which drifted apart and became the present-day continents] : From "The Solar System" by Encrenaz and Bibring, p. 135: "It is now possible to follow the history of the destruction of Pangaea and geological evolution that was a result. On the other hand, we have hardly any information about the continents that existed before that phase when there was just one: did Pangaea appear as a result of the incessant move- ment of the continents, shortly before the break-up, or had it existed as a stable entity for thousands of years? From what we know of the causes of continental drift, the first possibility seems more likely."

From "Exploration of the Universe" by Abell, Morrison, and Wolff, pp.262-3: "If we extrapolate the plates' motion backward we arrive, some 200 million years ago, at the supercontinent of Pangaea... The configuration of the continents before Pangaea is less well understood. It is clear that plate tectonics were at work, from the existence of old mountains (such as the Urals in the U.S.S.R. and the Appalachians in the U.S.) that were formed more than 200 million years ago. Recent studies indicate that plate tec- tonic activity in what is now North America can be traced back 1.5 billion years."

In other words, it is believed that Pangaea was not the original land- mass configuration, but there are no guesses about how it came to be.

RC Winther

Click here to return to the Astronomy Archives

NEWTON is an electronic community for Science, Math, and Computer Science K-12 Educators, sponsored and operated by Argonne National Laboratory's Educational Programs, Andrew Skipor, Ph.D., Head of Educational Programs.

For assistance with NEWTON contact a System Operator (, or at Argonne's Educational Programs

Educational Programs
Building 360
9700 S. Cass Ave.
Argonne, Illinois
60439-4845, USA
Update: June 2012
Weclome To Newton

Argonne National Laboratory