Featured Research

from universities, journals, and other organizations

Researchers Unearth Ancient Continental Rift Activity

Date:
July 30, 2004
Source:
University Of Alberta
Summary:
Researchers at the University of Alberta have found evidence that a 2,000-kilometre corridor stretching diagonally across northern Canada was under tremendous pressure to split in two about 2.7 billion years ago. It is the first evidence suggesting enormous continental landforms and plate tectonics existed that long ago.

Researchers at the University of Alberta have found evidence that a 2,000-kilometre corridor stretching diagonally across northern Canada was under tremendous pressure to split in two about 2.7 billion years ago. It is the first evidence suggesting enormous continental landforms and plate tectonics existed that long ago.

Related Articles


"Rifts are one hallmark of plate tectonics, and there is a huge debate in our field about whether or not large continents and plate tectonics existed on Earth in the Archean age, which is pre-2.5 billion years ago," said Dr. Larry Heaman, a professor of earth sciences at the U of A.

"Our findings suggest that a form of plate tectonics did occur in the Archean," said Dr. Russell Hartlaub, a post-doctoral fellow working with Heaman and lead author of a paper on the Archean rift discovery that appears recently in Precambrian Research.

For the past six years, the researchers have been studying rocks in the northern Lake Athabasca region of Saskatchewan. These rocks are collectively known as the Murmac Bay Group, and they are part of a corridor that runs from northeast Alberta to Baffin Island. Recently, Hartlaub and his colleagues discovered a sequence of Archean rocks--mainly quartzite and basalt--along this corridor that are consistent with "rift-related" activity.

Hartlaub analysed and dated the rocks before determining that the Murmac Bay Group is evidence of a failed rift in the ancient continent that has been named Nunavutia. He estimates the continent was larger than England, France and Germany combined. However, the researchers don't know yet if rifting succeeded in splitting any part of Nunavutia to form an ocean basin.

In studying the Murmac Bay Group, the researchers also discovered minerals in northern Saskatchewan that are 3.9 billion years old, and they've found rocks in the same area that date back 3.1 billion years. Heaman noted that these are some of the oldest minerals ever discovered. (In 1989, Dr. Sam Bowring of the Massachusetts Institute of Technology (MIT) found the oldest rock ever discovered on Earth, dating back four billion years, in Canada's Northwest Territories.)

Aside from the significance of the discovery to researchers trying to understand Earth's history and evolution, minerals this old will certainly draw the attention of people in the diamond exploration industry, Heaman said.

"Virtually all diamond deposits come from areas where you can find ancient crust preserved, such as we've found in northern Saskatchewan," he added.

"It's really exciting to find evidence of this large, ancient continent and these ancient crustal processes," Hartlaub said. "Our next step is to analyse the geochemical signatures of the minerals we've found to see if we can get an even better idea of what our Earth looked like more than two-and-a-half billion years ago."


Story Source:

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


Cite This Page:

University Of Alberta. "Researchers Unearth Ancient Continental Rift Activity." ScienceDaily. ScienceDaily, 30 July 2004. <www.sciencedaily.com/releases/2004/07/040729093451.htm>.
University Of Alberta. (2004, July 30). Researchers Unearth Ancient Continental Rift Activity. ScienceDaily. Retrieved November 1, 2014 from www.sciencedaily.com/releases/2004/07/040729093451.htm
University Of Alberta. "Researchers Unearth Ancient Continental Rift Activity." ScienceDaily. www.sciencedaily.com/releases/2004/07/040729093451.htm (accessed November 1, 2014).

Share This



More Earth & Climate News

Saturday, November 1, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

World's Salamanders At Risk From Flesh-Eating Fungus

World's Salamanders At Risk From Flesh-Eating Fungus

Newsy (Oct. 31, 2014) The import of salamanders around the globe is thought to be contributing to the spread of a deadly fungus. Video provided by Newsy
Powered by NewsLook.com
Controversial French Dam Halted After Death of Protester

Controversial French Dam Halted After Death of Protester

AFP (Oct. 31, 2014) Local French authorities Friday decided to suspend work on a controversial dam after the death last week of an activist protesting against the project that sparked uproar in the country. Duration: 01:05 Video provided by AFP
Powered by NewsLook.com
How A Chorus Led Scientists To A New Frog Species

How A Chorus Led Scientists To A New Frog Species

Newsy (Oct. 30, 2014) A frog noticed by a conservationist on New York's Staten Island has been confirmed as a new species after extensive study and genetic testing. Video provided by Newsy
Powered by NewsLook.com
Raw: Hawaii Lava Inches Closer

Raw: Hawaii Lava Inches Closer

AP (Oct. 30, 2014) Aerial video shows the path lava has carved across a portion of Hawaii's big island, threatening homes in the town of Pahoa. Officials say the flow was just over 230 yards from a roadway Thursday morning. (Oct. 30) Video provided by AP
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