Remote crater in Far North lures UNB researcher

A researcher from the University of New Brunswick will travel by float plane to a crater in the Far North formed hundreds of millions of years ago and not explored in more than 50 years.

Maree McGregor, a graduate student in earth sciences with UNB's Planetary and Space Science Centre, will be heading to the Northwest Territories to study the Nicholson Lake crater, the site of an asteroid strike 389 million years ago.

The impact crater is about 600 kilometres east of Yellowknife.

• Minerals found on Mars suggest crater once contained right elements for habitability

"Understanding when impact craters occur helps to understand the rate of impact bombardment on Earth," McGregor said. "This is important because impact cratering helps planets evolve."

The Nicholson Lake crater has been visited twice but not since the1960swhen an impact crater was confirmed. No studies have been undertaken since.

Next August, McGregorwill head to the Northwest Territories, where she will have access to islands that haven't been previously sampled. They will be easier to access in summer, because they won't be covered in ice.

What is an impact crater?

John Spray, director ofUNB'sPlanetary and Space Science Centre, said an impact crater is formed by an asteroid hitting a planetary body.

"The smaller asteroids can collide with the planets and put dents in thesurface," he said.

There are thousands of asteroids in the asteroid belt between Mars and Jupiter, at least 10,000 of which have been named and can vary in size, he said.

There are about 200 proven impact craters worldwide, butcraters are often difficult to locate because, like Nicholson Lake, they have been eroding or they're very remote, he said.

Never know it to see it

McGregor said if a person were in the field, it would be easy to miss the Nicholson crater, which hasevolved overtime.

"You wouldn't think straight away, 'This is an impact crater,'" she said. "You need to analyze the rocks, the features that are definitely formed by impact processes."

If we're able to date the craters and see how often they're occurring, we can somewhat predict how often they occur and if they pose a potential threat in the future.-MareeMcGregor

The crater is about 12 kilometres in diameter and covered in water.

It fits somewhere between a simple and complex crater.

"If you were to see Nicholson Lake in the field, it's not circular this is semi-circular and it's very flat and eroded because of all the glaciation in that region," saidMcGregor.

She said some of thebigger craters are about 180 kilometres.

Although she won't have access below lake level, she will be doing geological mapping,trying to understand Nicholson Lake and its petrography, or mineral content and other details,chemistry, age and the features created by the shock of the impact.

"That can help us understand how these impact craters areformed," she said.

UNB researcher to travel north to study 389-million-year-old crater

7 years ago

Duration 0:45

A graduate student from the University of New Brunswick will be visiting the Nicholson Lake crater in the Northwest Territories, the site of an asteroid strike that took place 389 million years ago.

A link to mass extinction

Through studying impact craters in the past, researchers have alsouncovered insights into the solar system and interactions between its planets.

By studying this particularimpact crater,McGregorishoping to understand themin general.

"If we're able to date the craters and see how often they're occurring, we can somewhat predict how often they occur and if they pose a potential threat in the future," she said.

"Impact cratering is important to study because it's linked to mass extinctions."

She's also researchingtheManicouaganand Moineriecraters, bothin Quebec.

There are about 30 craters across Canada, including the better-known Sudbury Basin in Ontario and one of the largest anywhere.

Destroyed over time

Some craters have been formed over two billion years, Spraysaid.

"The moon is covered in craters but on Earth we only have relatively few craters," he said. "That's because Earth is an active planet, whereas the moon is not the Earth actually destroys its craters over geological time."

McGregor received the2017Shoemaker Impact Cratering Awardfrom the Geological Society of America's Division of Planetary Geology.

The international award honours the memory of Eugene M. Shoemaker, a founder of the science of impact cratering who brought geological principles into the emerging discipline of planetary science.

McGregor is the 19th recipient of the Shoemaker Impact Cratering Award, and the third recipient from theUNBcentre.