Truemors
Digg
del.icio.us
AddToAny
Write
is reporting from
Member
NP Rank:
NP Rank:
Australia and Antarctica were once attached to North America
by yuls.source | July 28, 2008 at 12:16 pm | 159 views | 3 comments | 2 recommendations
The land “down under” turns out to have been “up on top” just 600 million years ago.
A small rock found in Antarctica’s mountains supports the hypothesis that Australia, Antarctica and North America were once clumped together as one continent.
For several decades, researchers have theorized that part of the ancient supercontinent Rodinia broke away from what is now the southwestern United States around 800 million to 600 million years ago, eventually drifting southward to become eastern Antarctica and Australia. The idea is known as the southwestern United States to East Antarctica (SWEAT) hypothesis.
There was no concrete evidence to support the SWEAT hypothesis until scientists came across a rock that gave them clues about the composition of the underlying crust of Antarctica.
Chemical tests run on the rock later revealed that it has a chemistry "very similar to a unique belt of igneous rocks in North America" that stretch from California through New Mexico to Kansas, Illinois and eventually New Brunswick and Newfoundland in Canada, Goodge said.
The belt stops suddenly at its western margin, leading geologists to suspect that some piece of crust had rifted away from what is now the West Coast of the United States.
"It just ends right where that ancient rift margin is," Goodge said. "And these rocks are basically not found in any other part of the world."
July 28, 2008 at 12:16 pm by yuls.source, 159 views, 3 comments
Crowd Power
SandraJC
Buffalo, New York, United Statesavsrldr
Athens, Texas, United States
David M Gibb
Eudunda, AustraliaTatters
Australia
Most RecentMost Recommended Comments (3)
at 16:11 on July 28th, 2008
yuls.source, I like this story. It's good stuff.
at 06:36 on July 29th, 2008
These sketches are from the Antarctic Peninsular and nearby Islands, I thought it was pretty cool that my home in Australia was once much closer to that wonderful icy continent down south, now it seems North America was once much closer too.
David M Gibb has contributed a photo to this story.
- reply
avsrldrat 06:58 on August 10th, 2008
This is Mt. Williams, located on Anvers Island off the Antarctic Pen. I'm am here working at a research station. This is just one view of the prestine beauty that surrounds this place. You can learn more about me and Antarctica at nomadplumber.com
avsrldr has contributed a photo to this story.