A summer search for early life and the origins of enigmatic volcanic rocks in the Arctic
This July, Geological Survey of Canada scientist Dr. Rob Rainbird is leading a team of Canadian and international scientists north of the Arctic Circle to look for some of the world’s oldest microfossils and clues about the origins of a huge ancient volcanic event. The expedition will examine a segment of the Earth’s crust by canoe along 200 km of the Coppermine River between the Dismal Lakes and Kugluktuk, collecting samples, taking measurements and conducting other scientific studies between July 11 and August 10, 2017. You can join this adventure by following the expedition’s blog.
- A journey through time by canoe
- Hunting for early life in Arctic Canada
- The beauty in movement of water downstream
- A Short History of Exploration in the Coppermine area
- A typical day with a field geologist
- A new view everyday in a dramatically changing landscape
A journey through time by canoe
Text and photos by Vivien Cumming – @drvivcumming
Early morning on the Gatineau River — a gentle mist rises from the surface of the glassy still water; the sun’s first pink rays sparkle in the moving current and catch the repellent fur of a beaver’s head as it comes up for air.
Gatineau River – photo credit Vivien Cumming
In the distance, the gentle sound of faster flowing water is punctuated by birds rising in the trees, dragonflies emerging to chase the buzz of mosquitoes and black flies — and the soft sound of paddle as it pushes through the water.
Then the clank as canoes collide and the splash of bodies falling into the water! Peace is broken. Chaos descends on the river as eight geologists find themselves floundering around in the water learning how to handle Canadian canoes, and themselves, in whitewater.
Fuelled by coffee, big barbecue-cooked breakfasts and hope that the cold river wouldn’t engulf us each day, we braved two days of whitewater river training with Boreal River Rescue and two days of whitewater paddling with Blackfeather Expeditions on the Gatineau River near Kazabazua.
We spent the days learning how to swim in whitewater, trying to read the signs of the river rapids, where you could be dragged under water or where a calm eddy could bring you a little peace. Tying ropes, throwing ropes and rescuing each other from the water, and most importantly, moving a canoe in a straight line down a river.
Whitewater canoe training on the Gatineau River – photo credit: Danny Peled
The reason— in July we embark on a ambitious scientific expedition to descend 200 km of the Coppermine River by canoe from Dismal Lakes to Kugluktuk where the river enters the Arctic Ocean. Eight geologists, four river guides, six canoes, 12 paddles (hopefully) and a lot of gear. A river renowned for its whitewater and a bunch of (mostly) middle-aged geologists with very little experience in canoes — it’s going to be an adventure!
The canoe is only the tool to make the adventure happen — the real adventure is in the science we will see along the way. Studying the rocks along the riverbank for the first time since the early explorer, George M. Douglas, followed a similar route along the river over 100 years ago (detailed in the book: Lands Forlorn).
These rocks will take us on a journey through 500 million years of Earth history, starting over 1.5 billion years ago when early multicellular life was beginning to emerge on Earth. We will study and sample rocks along the river banks as well as hike into the wilderness and use a drone for mapping the area.
We are on the lookout for some of the world’s oldest fossils; microscopic fossils of early eukaryotes (an organism whose cells have a nucleus containing DNA and other organelles enclosed within membranes). Carbon in the rocks will be studied to explain the environmental conditions these organisms lived in, and we will be searching for clues about the origins of a huge ancient volcanic event. One theory is that a massive outpouring of magma was caused by a mantle plume (large thermal upwelling originating from Earth’s interior) and another new theory is that it was triggered by a meteorite impact.
The training prepared us well, and more time was spent in the water than was perhaps desired, but its all in the name of safety and access to remote science. The journey down the Coppermine will take us through Earth’s history in Canada’s remote wilderness.
The 12-member expedition is led by Dr. Rob Rainbird, a scientist with the Geological Survey of Canada, and a team of Canadian and international scientists. National Geographic and BBC photographer, writer and geologist, Dr Vivien Cumming, will be documenting this expedition north of the Arctic Circle.
Getting ready for canoeing on the challenging Coppermine river with 2 days of whitewater river training – photo credit Danny Peled
The team is in the field between July 11 and August 11, 2017. You can join this adventure to hear about paddling the Coppermine, bug bites, a month without a shower, weather, wildlife and of course, the Earth’s history, by following the expedition’s blog at science.gc.ca. Follow @drvivcumming on Instagram and Twitter for social media updates.
Detail of a canoe paddle blade – photo credit Vivien Cumming
Hunting for early life in Arctic Canada
Text and photos by Vivien Cumming – @drvivcumming
A week in Arctic Canada — and an impressive tally. Bug bite count well over 1,000. Rock samples collected over 250. Freeze-dried meals eaten – 63. And the list goes on: minor injuries – 3, major injuries – 0, fish caught – 4, caribou seen – over 20, bears – 0, moose – 1, wolf – 1.
The polar tundra environment of Arctic Canada is a summertime breeding ground for mosquitos and playground for geologists and caribou alike. It’s an ideal place to study Earth history. There is generally very little soil and vegetation — meaning the rocks are well exposed, and northern Canada holds some of the Earth’s most exciting undiscovered geology.
It turns out we are on the edge of this landscape, the final flanks of the boreal forest. Here there is soil and shrubby vegetation. Adrian our Inuit wildlife monitor (bear guard) points out the blueberry bushes and caribou tracks. Unfortunately, it’s late July and the blueberries aren’t out until the fall, but the mosquitoes sure are.
Mosquitos fly over the bright blue waters of the western lake of the Dismal Lakes - Vivien Cumming
Every day we wake up praying for cold and wind so that the bugs don’t plague us. Some days that prayer is answered, but others have beautiful sky blue days with not a breath of wind. Dismal Lakes where we camped doesn’t look dismal at all. A beautiful crisp blue reflecting the piercing azure skies inviting us in for a swim, but one toe in and that idea is soon dismissed. The icy water is a gentle reminder that we are in the Arctic.
It must be one of the few places in the world where I actually prefer to be blown around by cold Arctic winds than have hot summery days — anything but the bugs biting every inch of my body. No matter how many clothes and layers you are wearing they still bite. The mosquitos here must have evolved stronger to deal with caribou hide as nowhere else in the world has a mosquito been able to penetrate my thick, Gore-Tex waterproof trousers.
The mosquitos that seem to be able to bite through Gore-Tex trousers! - Vivien Cumming.
We are about 80 km southwest of the Inuit settlement of Kugluktuk that lies on the Arctic coast and will be the end point to our 200 km lake and river journey. The vegetation is declining as we move north. In this part of Canada, it’s a hike across the boggy tundra to reach the rocky outcrops we are here to see.
From the top of a nearby mountain, you can see what we came here for. Escarpment after escarpment as far as the eye can see. Layers of ancient sedimentary rock that have been tilted by tectonic movement and that can now be seen making up the landscape of vast areas of northern Canada.
Looking over the landscape filled with rocky escarpments made up of rocks that were deposited under the sea over a billion years ago - Vivien Cumming.
Here the scientists from the Geological Survey of Canada cross bog after bog as they sample each layer of rock. Every one is a time capsule of marine conditions over a billion years ago.
Corentin Loron of the University of Liège in Belgium has been hunting for layers of chert that contain microfossils that can tell us more about the dawn of life. Rocks just over a billion years old are known to contain evidence of life becoming more complex than the single-celled organisms life started out as. As Corentin finds one of these fossil rich layers he holds up the hard, dark rock explaining that there are likely to be species of fossils in here that are totally new to science: “What’s exciting is finding out how and when life diversified, what the world looked liked a billion years ago, what was living back then.”
PhD student Corentin Loron surveying the rocks - Vivien Cumming.
Our first week in the Arctic has been spent on the shores of Dismal Lakes studying the over one-billion year old sedimentary rocks around the shores and mountains of the lakes. This is the first part of our journey through time looking at a time when life on Earth began to get bigger and the volcanic eruptions that made it hard for life at that time.
Each day involves getting up around 7 a.m. for a breakfast of oatmeal. Then we head out into the field and spend the entire day hiking through the tundra measuring, recording and sampling rocks — each layer of sedimentary rock read like the pages of a book getting younger in time.
Lunch consists of sausage, cheese, apples and trail mix, and then its home around 6 p.m. for a dinner of rehydrated freeze-dried food. Anything tastes good when you have spent that long outside. Light summer evenings spent writing up results, playing cards or sleeping when the days are particularly hard going. Life is simple because it has to be simple. No creature comforts, just the great outdoors as a home. I’m sure most of us will agree, there’s nothing quite like being out in the wilderness far from home embracing everything nature has to throw at us.
Getting to location by float plane - there are so many lakes up north you just pick your lake, land and make camp - the canoes arrive - Vivien Cumming.
The next part of our journey will see us hop into our canoes to travel down through Dismal Lakes to the Kendall River towards the Coppermine River. The challenge will be fitting all of our personal field gear, food, tents, rocks, etc., into our canoes. Can we do it and stay afloat and will the weather hold for our journey? You never know in the Arctic…
The beauty in movement of water downstream
Text and photos by Vivien Cumming – @drvivcumming
What happens when you fly 12 people into a field camp in a plane and then have to get them and all their food and belongings into six canoes? You send stuff back in the plane!
We didn’t send too much back though. I’m amazed what you can fit in six canoes: 12 people, 24 big barrels, six small barrels, two bags full of tents, a fire box, a gas stove, two wannigans (kitchen boxes), two pelican cases containing drones, computers and cameras, and last but not least, a guitar.
Most of our barrels are filled with food, and we have been eating well. We’ve been cooking over fires in the firebox so as not to leave a trace at our campsites. Roast beef, freshly caught fish, eggs and bacon for breakfast, and my personal favourite — fire-baked cinnamon buns!
Usually fieldwork done by the Geological Survey of Canada (GSC) in remote parts of the North is executed by helicopter, but there is something about using human muscle and the power of water to get to where you want to go. As we get more proficient at reading the river, we start to see that at times it requires no effort, just ability to see how the water will move you. Always limited by where the river takes you, it brings an understanding of the lives of early explorers.
Hauling a loaded canoe up the beach to set up camp - Vivien Cumming.
We are following the route of George Douglas and August Sandberg, who explored this region in 1911–12 in search of the source of copper nuggets that could be found in the riverbed — hence the name Coppermine River.
The first part of our journey takes us east through the three Dismal Lakes to the Kendall River, which then joins the Coppermine River. Douglas got through the lakes in two days describing them as getting less and less dismal the further east you go.
It took us three days to get down the lakes, and we had very similar weather conditions to Douglas, our first day being the most challenging. As we packed up the canoes, the wind picked up and showed no sign of dying, so we had to paddle head on into the wind to get across the lake. Hard going for our first day in the canoes, fully loaded with food and gear.
The second lake gave us the opposite experience. The wind was behind us so we rafted up and used a tarp as a sail and paddles duck-taped together as a mast (it’s amazing what you can do with duct tape) and whistled on down the lake.
The third lake again was not so friendly. The morning we woke up to do this lake, the wind was strong and producing waves side on to our direction of travel, not safe in fully loaded canoes, so we waited it out all day and ended up leaving at 9 p.m. when the wind had died. Arctic summer nights make this easy as the sun only goes down for an instant and it never gets dark. We arrived at 2 a.m. — a beautiful sunset paddle with a view on the way of a mother grizzly and her three cubs playing on the shore.
Surveying rapids on the Kendall River - Vivien Cumming.
The Kendall River then posed the next challenge — our first go at rapids in fully loaded canoes. We all made it through; one canoe ended up going backwards down the rapids, but nothing too dramatic to contend with. As we reached the end of the river, the vastness of the Coppermine River came into view — wide and mighty — suddenly we experienced what its like to paddle in fast-flowing current. You don’t need to paddle that much really!
Each time we arrive at camp, the first priority is getting some kind of shelter up. In our modern world of cities, we take for granted what a roof over our heads means for us. In the wilderness, you know only too well how important shelter is. It can be the difference between life and death, and up here the weather changes in a heartbeat, from hot sunny days to freezing wind and rain at any moment. Second priority — food of course!
Tom Skulski checking out lava flow samples with his hand lens - Vivien Cumming.
During this part of the trip, we are sampling lava flows from a huge volcanic event, called the Mackenzie event, which overlies the life-bearing sedimentary rocks we were studying at Dismal Lakes. Tom Skulski from the GSC is leading us up into endless layers of lava making up the mountains all around us. I call them the burnt pancake mountains (they are actually called the September Mountains), because the layers of dark basaltic lava look like a stack of pancakes.
The scale of these volcanic eruptions is huge — similar to the Columbia River flood basalts. Evidence from the ancient eruptions here can be found over 2,000 km away in southern Canada. A previous study, published in 1996 by Baragar and colleagues, found about 150 flows with a total thickness of 3 km, and we are trying to sample them all!
Mountains made up of lava flows on top of each other - burnt pancakes - Vivien Cumming.
Eruptions of this scale have a huge impact on the Earth’s climate system and life. We don’t yet know what this eruption was caused by, maybe a meteorite impact or a hot spot in the Earth’s mantle, like what’s below Hawaii today.
Events of this magnitude are similar to the huge extinction events like the one that wiped out the dinosaurs. We are here to find out what this event did to life at the time and how long these eruptions lasted. “That’s one of the reasons we are here — we don’t know,” says Rob Rainbird, of the GSC, who is leading the trip.
We are looking at the rocks before, during and after this event — to get a sense of how the planet reacted to such a major outpouring of magma. We can certainly see it all around us now. Making up this stunning landscape.
The Coppermine River snakes through a stunning landscape made up of volcanic rocks at the edge of the tree line - Vivien Cumming.
The landscape here reminds me of parts of my home country of Scotland, rolling hills and patchy trees, but here our efforts have been rewarded with sightings of caribou, muskoxen, grizzly bears, bald eagles, moose, wolves and the little sparrow-like bird we rescued from drowning in the river.
As the water kindly moves us further down the Coppermine River, we will come across the rocks that overlie the pancake lava flows and complete our story of this strange time period over a billion years ago.
A Short History of Exploration in the Coppermine area
By Pat Hunt
The Coppermine River area has been home to the Kitlinermiut for thousands of years. The Kitlinermiut were called Coppermine Inuit by early explorers because the Inuit gathered copper from the banks of the Coppermine River. It was rumours of copper and other minerals that brought western explorers to the area.
In 1771, Samuel Hearne explored the area, and in his third attempt made the crossing on foot from Churchill, Manitoba, overland to the mouth of the Coppermine River, a distance of almost 1,700 km. Hearne’s success as an explorer was largely the result of his adaptation to the way of life and the movement of his Indigenous guides. Unfortunately, he was pulled into the clash of cultures when his guides came upon a group of Inuit hunters who were their sworn enemies. A first-hand witness to the murder of 20 Inuit, Hearne named the place Bloody Falls and wrote that he could never “reflect on the transactions of that horrid day without shedding tears.” He was further disillusioned with the area for its mineral potential when intense searching yielded only one four-pound lump of copper.
In 1900, J. ”Mac” Bell — nephew of Robert Bell, the distinguished Geological Survey of Canada (GSC) geologist — and Charles Camsell started their field season of the exploration of Great Bear Lake and the Coppermine River for the GSC. Bell hired two Métis guides and Charles Bunn, a young American looking for adventure. They took a steamer to Fort Norman and then travelled by canoe up the Great Bear River to Great Bear Lake. They spent several months exploring the north shore of the lake with an excursion inland up the Dease River and across to the Coppermine River. Then Camsell and Bell left the group to explore the area in detail.
Canoeing up the Dease River to the Coppermine River; photo from George M. Douglas, Lands Forlorn: A Story of an Expedition to Hearne's Coppermine River, 1912
Near the Dismal Lakes, they encountered a group of Inuit people who fled at the sight of these strange men. Bell and Camsell helped themselves to their meat cache and left a tin plate and two steel needles as payment. They found out later that the Inuit followed them for two days to ensure they had left the area but determined that they must have been friendly since they had left things of such value. Upon their return to Great Bear Lake, Bell and Camsell found out that Charles Bunn, the American adventurer, had separated from his guide and was lost.
They searched for Bunn as long as they dared but had to give up and resume their travels. Camsell and Bell returned south by way of the Camsell River and overland to Great Slave Lake. They were only half way back when they realized they were not going to make it before winter set in. Fortunately, they met a group of Dogrib Indians who showed them the way, and so they returned safely to Fort Rae on Great Slave Lake. Good luck also favoured Bunn who, after eight days of wandering, came across an Indigenous group of people who took him back to Fort Norman on the Mackenzie River.
In 1911 and 1912, a private expedition was funded to explore and map in detail the Coppermine River. The three-man exploration party was led by George M. Douglas, his brother Lionel and Dr. August Sandbury, a geologist. The expedition left Edmonton by York boat, a solid cargo vessel, and travelled to the headwaters of the Great Bear River.
York boat on Great Bear Lake (Douglas, Lands Forlorn)
There, they tracked their York boat up the rapids-filled river to Great Bear Lake and sailed across the stormy lake to the mouth of the Dease River in the northeaster corner. Lionel Douglas stayed to build a cabin for the winter, while his brother George and August Sandbury canoed, hiked and portaged up the Dease to the Dismal Lakes and then down the Kendall River to reach the Coppermine River, which they explored and mapped before returning to the cabin.
Wintering over on Great Bear Lake (Douglas, Lands Forlorn)
After a long winter, the Douglas party returned to the Coppermine River by dogsled and foot. They made it all the way to the Coronation Gulf lying off the northern coast of mainland Nunavut, meeting some of the Copper Inuit along the way. On this expedition, they befriended and stayed with two tragic figures. One was Father Rouvière who, along with another priest, was murdered by Inuit near the mouth of the Coppermine River the following year. The second was John Hornby, who later starved to death with his 18-year-old nephew and another young man in 1927 on the Thelon River.
These and other expeditions in the area showed that this isolated, forbidding area could be a wild and dangerous place in which only the well prepared can survive.
By Pat Hunt
The earliest account of the exploration of the Coppermine area is that of Samuel Hearne in 1771.
J. M. Bell and Charles Camsell described their 1900 field explorations in the GSC’s annual report volume XIII pp. 95A–103A, downloadable at https://doi.org/10.4095/225151. Their exploits are also discussed by Jean S. McGill, Northern Adventures, 1974, a pdf copy of which I can loan.
George M. Douglas embarked on a major expedition to the Coppermine River in 1911 and published his story in Lands Forlorn: A Story of an Expedition to Hearne's Coppermine River, 1912, downloadable at https://archive.org/details/landsforlornstor00douguoft
Vilhjalmur Stefansson spent several years exploring the Arctic and travelled extensively on the Coppermine River. His exploits were published in My life with the Eskimo, 1908, downloadable at https://archive.org/details/mylifewitheskim00andegoog
The Canadian Arctic Expedition of 1913–1916 Southern Party published the results of their exploration the Coppermine River area in “Report of the Canadian Arctic Expedition 1913–18” Volume XI: Geology and Geography, the map from which can be downloaded at https://doi.org/10.4095/107422; their description of the Coppermine area simply repeats George Douglas’s account and geology.
A typical day with a field geologist
Text and photos by Vivien Cumming – @drvivcumming
For this post we thought we’d give you an idea of what a typical day is like in the field for a geologist in the Arctic. Of course, every day is different, but here is an example.
7:02 Alarm goes off; it’s already bright daylight outside.
7:26 The camp “rooster” lets out his call — breakfast is ready — get up, unzip the down sleeping bag to let in the bracing Arctic air and get dressed.
7:33 Breakfast: coffee, tea, eggs and bacon, oatmeal or some other delicious concoction created by our fantastic canoe guides, with cinnamon buns on a really good day!
Photo 1: Freshly baked bread to keep us going.
8:11 More coffee.
8:17 Toilet shuttles begin: take the camp spade, dig a hole, do your business.
8:34 Bags packed with field gear — waterproofs, warm layers, cameras, notebooks, rock hammers, sample bags, first aid kits, bear spray, flares and bear bangers, emergency blankets, field computers — lunch and trail mix ready for a day in the wild.
9:13 Head off into the field. We camp by the river, and the rocks are usually in the mountains so there are a fair few kilometres to hike through forest and across bogs to get to what we want to see, swatting away the bugs as we go.
10:56 Reach the first rocky outcrop. Today, we’re sampling layers and layers of lava that make up the mountains. On other days, we’ve been measuring sedimentary structures left by ancient rivers or collecting samples of organic matter–rich chert, a type of sedimentary rock, to look for evidence of early life.
Photo 2 - Hiking out across the landscape with equipment on the back.
11:07 Tom Skulski gets out his hand lens (a mini magnifying glass) and examines the crystals in the rocks to find out their composition.
11:23 We sample the central part of the lava flow. You can tell where this by finding the part of the outcrop that has the least holes in it; these are called vesicles and are produced by bubbles of gas that rise to the top of the flow captured in time when the flow cools.
11:33 The samples is are bagged, and GPS coordinates are logged and input into the field computer. This allows the locations to be plotted up on a geological and topographic map to assess how many more flows need to be sampled and to see the geographical distribution of the samples.
12:49 Three more flows have been sampled, and we have reached the top of the mountain. It’s time for lunch overlooking a huge bend in the Coppermine River, aptly named Big Bend.
13:19 We trace the top of one lava flow across a large glacial valley to another mountain, and it seems there are more lava flows to go and sample.
13:31 Étienne Girard launches a tiny drone helicopter to capture high-resolution 3D images of the flows, which will help us reconstruct their original pathways.
13:45 Étienne flies the drone over the back of a ridge so we can see if there are more flows to sample on the other side.
Photo 3 - Looking over the Coppermine River.
14:12 There are more flows to sample, so we pack up the drone, leave the previous samples in a big white bag to find them on our way back and hike off across the valley tracing out more lava flows.
16:34 We have sampled all the flows that have led us to the top of a mountain, and we stop to take in the view over the winding Coppermine River.
16:47 A quick snack and then it’s a long walk back to camp, picking up samples along the way, watching out for wildlife and swatting away more bugs.
19:04 Arrive back in camp, tired after our long walk.
19:14 A quick river wash in the cold water — there’s nothing like refreshing ice cold water to wash away a long day hiking.
19:37 Dinner is ready. Our canoe guides, Jess, Chris, Dylan and John, must be thanked for their incredible and ingenious cooking. We would all agree that we have never eaten so well in the field before. Dutch oven roast beef beats freeze dried camping meals any day!
Photo 4 - Camp life.
20:49 The daily notes are written up and recorded, GPS points are input into field computers, and geological maps are studied to search for our next target. Some scrabble and card games also go on in the background.
22:11 Get ready for bed. The eternal Arctic light in the summer makes it hard to know when night falls, but a long day in the field is enough to put you straight to sleep.
This describes a particular day in the field, but every day is different and every rock type requires different methods.
A new view everyday in a dramatically changing landscape
Text and photos by Vivien Cumming – @drvivcumming
The river winds its way, cutting the easiest path through a remote landscape that only those brave enough to travel it are lucky to see. Our journey is somehow increasing in length everyday — the shortest path is not always the easiest. Our navigation through the water avoids rocks and shallows and is more haphazard than can accurately be measured on a map. We are reminded by our wise river guides: “Follow the water, and it will show you the way.”
About halfway down the roughly 200-km section of the Coppermine River, the landscape changed dramatically.
Green mountains made up of endless layers of dark lava flows with a gentle, wide river flowing between them gave way to steeper-walled canyons of red sandstone, the overlying rocks in the sequence. Here, the river is much more unforgiving. We tackled our fair share of rapids, ones we knew were ahead and ones that were not expected.
Photo 1 - Tackling rapids in the Coppermine River with fully loaded canoes.
We had already gone through several barrels of food, but the canoes didn’t get much lighter since the barrels were now used for our rock samples — perfect ballast for some expeditions, I’m sure, but not for tackling rapids with four-foot waves that fill your canoe with water!
The rapids along the Coppermine are memorable for their turbulence and their beauty, and have been given apt names: Muskox Rapids, where we saw a large herd of muskoxen grazing their way across the landscape; Sandstone Rapids, surrounded by layered cliffs of red sandstone; and Escape Rapids, where the escape is through a narrow gorge, which made for a spectacular camping spot on the edge of a rocky cliff. A canoe group following us didn’t escape its clutches: the swirling currents swallowed one of their boats, which we were able to help them recover.
The sandstones here are fluvial deposits, deposited by another river more than a billion years ago. There is something wonderful about travelling along a river cutting its way through rocks that are remnants of ancient rivers gone by.
Photo 2 - Sandstone canyons of the Husky Creek Formation, ancient fluvial deposits.
As you examine layers of sedimentary rocks with geologists, their minds are always asking the questions: What kind of environment were these sediments deposited in? When were they laid down? How and under what climatic conditions? What brought these sediments here: a river, an ocean, a glacier? We have seen or could imagine all possibilitiesl on this journey through time.
The structures and minerals in the rocks give clues to how they were deposited. You can even tell the direction an ancient river flowed from the structures formed by the currents and imprinted in the rock. Alessandro Ielpi, a fluvial sedimentologist from Laurentian University, and his student Robbie Meek are the first to meticulously measure these structures in the sandstone so that they can build up a picture of how the area once looked.
Each day, they come back exclaiming about all the new structures they have discovered in the rocks, most of which we can see on river banks today, like ripples and mud cracks that have been preserved to tell the story of the path of a fossilized river.
Photo 3 - Modern ripples in sand sitting on top of ancient ripples in sandstone.
An important part of this trip is finding out the exact age of these rocks. We already know they are roughly just over a billion years old, but more precise dating would allow us to pinpoint exactly how the huge volcanic eruptions and other forces affected life and the climate.
Bill Davis of the Geological Survey of Canada has been collecting samples throughout the trip to find samples of zircon, a very hardy mineral that can be used to determine the age of rocks through radioactive elements — isotopes — held within the mineral.
As the river winds its way through spectacular canyons and gorges, we reach yet another set of sedimentary rocks on top of the red fluvial sandstones. They are lightly coloured sandstones and dark shales deposited in a marine environment, suggesting a higher sea level in ancient times. The shales show small black flakes, evidence that more microfossils might be preserved. By comparing the fossils found before and after the volcanic events, we can get an idea of how this huge eruption affected life and consider whether it helped or hindered the diversification of life on this planet.
The fossils we are looking for are broadly named as Acritarchs. The word comes from the ancient Greek words acritos meaning confused and arch meaning old. So as you can surmise, we are looking at some old and confusing rocks! And what is most confusing is that in the field all we can do is sample them — we won’t see the actual fossils themselves until we get back to a lab and use powerful microscopes to examine them.
Early explorers came here in search of the source of copper, travelling up and down the Coppermine River by canoe, sourcing food from the land along the way and wearing animal skins. We come here with our modern canoes, barrels of food and GORE-TEX clothing, examining the same rocks, this time in search of the story of life — but, as a nice link to earlier expeditions, we did also find a small nugget of copper.
Photo 4: The spectacular Bloody Falls, not suitable for a canoe!
Our last night is spent at Bloody Falls, now called Kugluk, named by the eighteenth-century English explorer Samuel Hearne, the first European to travel across northern Canada to the Arctic Ocean. The name he gave was fitting, since it was here that his Chipewyan Dene guides massacred a group of Inuit in 1771. Today, the scene is a spectacular set of rapids too dangerous for canoes and teeming with Arctic char making their way up river to spawn. For us, it means a long portage, carrying rocks and canoes around this still somewhat terrifying obstacle.
Four golden eagles appear to guide us as we sail our linked canoes down the last section of river, buffeted by favourable southerly winds. Entering Kugluktuk, the Inuit hamlet of 1,500 at the mouth of the Coppermine River on the Arctic Ocean’s coast, we are warmly greeted by children’s smiling faces and many questions about our adventure on this legendary river.
Rob Rainbird, the leader of the expedition, reflects on this amazing journey: “This was a dream come true, to mount a research expedition that accomplished all of its goals at the same time as providing our own low-cost, low-impact transportation, and having maybe just a little bit of fun along the way. Thanks to great weather, an excellent research team and expert guiding, we did it!”
Photo 5: The team at Bloody Falls.
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