Advertisement

Alaska volcano discoveries signal Canada’s need for closer monitoring

Scientists with the U.S. Geological Survey (USGS) and the U.S. Forest Service have discovered a dozen new volcanoes in Alaska, and what they've found in the magma flows from these volcanoes point straight at one of our own — Mount Edziza, in northern British Columbia.

We don't often think of volcanoes when we're listing off Canada's natural wonders, but the country is home to several of them; of course, many of them are long dormant or extinct. The most volcanically-active region in the country stretches from central B.C. through the Yukon and edges into Alaska, and is known as the Northern Cordilleran Volcanic Province (NCVP). It's part of Canada's contribution to the infamous Pacific Ring of Fire.

[ Related: A blast of a find: 12 new Alaskan volcanoes ]

So how do you find a volcano that's not erupting — or maybe hasn't erupted in hundreds or thousands of years? Geologists can study magma flows, whether they're happening right now or have been solidified for millions of years, and use the chemicals and minerals they find in the flows to track not only where the magma came from and from how deep down, but also the timing of the eruption and even the conditions on the surface (or in the water) when the magma cooled.

Over the past four years, a group of geologists have been hiking and diving their way through southeastern Alaska and its coastal waters, trying to get a better understanding the local volcanism. In that time, they've located no fewer than 12 previously unknown volcanoes in the region, and they believe there are even more still to be found. Some are small cones of solidified lava now hidden from sight by thick boreal forests or beneath dark waters, while others are maars — craters formed on the floor of the ocean when hot lava flows up from under the ground, contacts the cold water and explodes like a bomb.

Taking samples from 25 different magma flows from these volcanoes, the geologists found that the timing of these flows matched the last eruption of Mount Edgecumbe, located on Kruzof Island, just off the coast of the Alaskan panhandle, but that was the only part of them that matched.

Delving into the chemistry and minerals of the flows though, the geologists found an unexpected match in a volcano a little further away to the east — Mount Edziza, the highest confirmed volcano in Canada — which last erupted around 10,000 years ago, about the same time as Mount Edgecumbe.

So, what's the point of going to the trouble to discover hidden volcanoes that aren't just remote, they're downright difficult to get to and haven't erupted in recorded history? Well, quiet or not, they can still tell us some interesting things about our planet. For instance, some of the coastal lava flows rolled over beaches, given us not only a preserved snapshot of the plants and sea life present at the time of the eruption, but also an indication of how much the sea level has risen since the last glaciers of the last Ice Age pressed the Earth's crust down. Some of the lava flows actually have a distinct 'thumbprint' of glaciers they touched when they were active.

Also, there's plenty of evidence that the last glacial melt in that region touched off volcanic eruptions, as the earth 'rebounded' from the loss of having ice several kilometres thick pressing down on it. So, with glaciers melting now due to climate change, this 'rebound' will likely happen again, and we could be looking at more volcanic eruptions in northwestern Canada sometime in the near or at least not-too-distant future.

Canadian volcanology isn't a particularly big field, and there aren't that many scientists, relatively speaking, studying the potential for the volcanoes we already know about, let alone discover and study the ones we don't know about.

However, Canada is still volcanically active. It's only due to the active volcanoes being so far away from any settlements that we don't hear about them more often. Still, a volcano known as 'The Volcano', at the southern end of the Northern Cordilleran Volcanic Province (NCVP), erupted just over 100 years ago, spreading lava flows for 22 kms before calming down. Before that, the eruption of the Tseax Cone — also in the NCVP — caused what is considered Canada's worst geophysical disaster when it erupted in the late 1700s, destroying two villages of the Nisga'a people and killing around 2,000 people, who apparently were suffocated by gases emitted during the eruption.

[ More Geekquinox: 2013 Weston Youth Innovation Award winner Adam Noble makes amazing discoveries: A Yahoo! Exclusive ]

Unlike other countries, Canada does not monitor its volcanoes closely, and even with the existing monitors in place to detect earthquakes, it's unlikely that we'd know that a volcano was erupting here until well after it happened. Even with their remote locations, there are still communities that could be impacted by such an eruption, and as we've seen with volcanoes in Iceland and more recently in Alaska, ash from volcanic eruptions can cause serious disruptions in air traffic, grounding flights and putting people already in the air at risk.

Given the destructive potential of volcanoes, monitoring them is crucial for public safety. The discovery of these previously unknown volcanoes now raises the question of just how many more geologists are going to find in the area, and to just how far of an extent did Mount Edziza and the Northern Cordilleran Volcanic Province reach. We might not see any major eruptions from Canadian volcanoes, and earthquakes are likely a more pressing concern, but we can only benefit from better monitoring, both in keeping Canadians safe and in contributing to the collective knowledge about volcanoes and the processes that lead up to an eruption. If any young Canadians were looking for a future field of study, geology and volcanism might become a good 'growth industry'.

(Images courtesy: Wikimedia Commons, USGS)

Geek out with the latest in science and weather.
Follow @ygeekquinox on Twitter!