Featured Research

from universities, journals, and other organizations

SFU Geologist Finds Evidence Of Australia/North America Link

Date:
March 5, 1998
Source:
Simon Fraser University
Summary:
Thinking of going to Australia but dreading the long flight over the Pacific Ocean? Ponder this: if you'd been around 1.6 billion years ago, you could have walked from British Columbia.

Thinking of going to Australia but dreading the long flight over the Pacific Ocean? Ponder this: if you'd been around 1.6 billion years ago, you could have walked from British Columbia.

That's because mounting evidence suggests that the land mass we know as Australia may once have been joined to North America at the Yukon before drifting apart about one billion years ago.

It sounds far-fetched, considering the thousands of kilometres separating the two continents today, but on a geological time scale it's easily possible, says Derek Thorkelson, a professor of earth sciences at Simon Fraser University. He's just wrapping up a five-year study that offers convincing evidence of the Yukon/Australia connection.

Thorkelson focused on a series of unusual rock formations, known as 'breccias,' scattered over 3,500 sq km in the Wernecke Mountains of east-central Yukon. Because these formations - some of which are several kilometres long - are strikingly different in appearance from surrounding rocks, geologists have long puzzled over their origins.

Thorkelson's study -- which involved extensive geological mapping, geochemical analysis and mineral assessment in the area -- shows that the breccias (pronounced 'bretch-ee-as") were formed from a series of underground explosions caused by violent expansion of gas from liquid.

"This process is fairly well understood and is not that uncommon," says Thorkelson. "But in this case, the process of brecciation led to the precipitation of important ore minerals, such as copper, gold, cobalt and uranium."

As it turns out, the Yukon breccia rocks look identical to some underground breccia rocks in southern Australia at the site of the huge Olympic Dam copper and gold mine. Eager to make a more positive match, Thorkelson sent rock samples from the Yukon site to a University of Alberta lab for dating.

The Yukon rocks are about 1.59 billion-years-old - the same age as the Olympic Dam rocks.

"This Yukon/Australia connection was suggested about 10 years ago," says Thorkelson, "but there was no age determination of any quality. With this new information, we're able to confidently draw a direct correlation."

Not suprisingly, mineral exploration in the Wernecke Mountains has intensified in recent years.

Thorkelson notes there are other geological clues pointing to a Yukon/Australia link. It's even speculated that a third continent, Antarctica, was part of the puzzle.

Still skeptical? Don't forget, says Thorkelson, that the earth is estimated to be about 4.5 billion-years-old. Movement of the earth's crust - known as plate tectonics - likely began about three billion years ago. By contrast, the separation of the Americas from Europe and Africa to form the Atlantic Ocean happened a mere 200 million years ago.

"In 1.6 billion years, there could have been numerous openings and closings of ocean basins," he says. "North America and Australia could have been involved in several continental collisions and separations between then and now.

"So in a geological sense, it's not remarkable putting these continents together. The interesting thing is trying to find out where they were together."

Thorkelson will outline the results of his Yukon breccia study at the upcoming Lithoprobe conference, which takes place this week (March 5-8) at SFU's Harbour Centre campus.

Lithoprobe is a 20-year, $100 million national geoscience project to develop a comprehensive understanding of the evolution of the North American continent. As many as 600 earth science researchers across the country are working on studies related to 10 geological transects, or cross-sections, of Canada.


Story Source:

The above story is based on materials provided by Simon Fraser University. Note: Materials may be edited for content and length.


Cite This Page:

Simon Fraser University. "SFU Geologist Finds Evidence Of Australia/North America Link." ScienceDaily. ScienceDaily, 5 March 1998. <www.sciencedaily.com/releases/1998/03/980305053817.htm>.
Simon Fraser University. (1998, March 5). SFU Geologist Finds Evidence Of Australia/North America Link. ScienceDaily. Retrieved October 20, 2014 from www.sciencedaily.com/releases/1998/03/980305053817.htm
Simon Fraser University. "SFU Geologist Finds Evidence Of Australia/North America Link." ScienceDaily. www.sciencedaily.com/releases/1998/03/980305053817.htm (accessed October 20, 2014).

Share This



More Earth & Climate News

Monday, October 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Hey, Doc! Sewage, Beer and Food Scraps Can Power Chevrolet’s Bi-Fuel Impala

Hey, Doc! Sewage, Beer and Food Scraps Can Power Chevrolet’s Bi-Fuel Impala

3BL Media (Oct. 20, 2014) — Hey, Doc! Sewage, Beer and Food Scraps Can Power Chevrolet’s Bi-fuel Impala Video provided by 3BL
Powered by NewsLook.com
White Rhino's Death In Kenya Means Just 6 Are Left

White Rhino's Death In Kenya Means Just 6 Are Left

Newsy (Oct. 20, 2014) — Suni, a rare northern white rhino at Ol Pejeta Conservancy, died Friday. This, as many media have pointed out, leaves people fearing extinction. Video provided by Newsy
Powered by NewsLook.com
Beijing Marathon Runners Brave Hazardous Air Pollution

Beijing Marathon Runners Brave Hazardous Air Pollution

AFP (Oct. 19, 2014) — Tens of thousands of runners battled thick smog at the Beijing Marathon on Sunday, with some donning masks as the levels of PM2.5 small pollutant particles soared to 16 times the maximum recommended level. Duration: 00:54 Video provided by AFP
Powered by NewsLook.com
As Sweden Hunts For Sub, "Cold War" Comparisons Flourish

As Sweden Hunts For Sub, "Cold War" Comparisons Flourish

Newsy (Oct. 19, 2014) — With Sweden on the look-out for a suspected Russian sub, a lot of people are talking about the Cold War, but is it an apt comparison? Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:

Strange & Offbeat Stories

 

Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins