Top Ten Geological Wonders of Banff, Yoho, and Jasper National Parks Dale Leckie, Ph.D., P.Geol. Brokenpoplars.Ca
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Top Ten Geological Wonders of Banff, Yoho, and Jasper National Parks Dale Leckie, Ph.D., P.Geol. brokenpoplars.ca Dale Leckie is the award-winning author of the #1 bestselling Rocks, Ridges, and Rivers: Geological Wonders of Banff, Yoho, and Jasper National Parks. ISBN Number 978-0- 9959082-0-8, 216 pages. Available at bookstores. Rocks, Ridges, and Rivers: Geological Wonders of Banff, Yoho, and Jasper National Parks 1. Canyons, caves, and lakes of the Maligne River, Jasper National Park Dale Leckie, Ph.D., P.Geol. A spectacular spot in the Jasper Medicine Lake is dry most of the time, area is the canyons, caves, and lakes of because most of the lake drains away the Maligne River system. The Maligne through its underground plumbing River enters the Athabasca River valley as system. a 90 metre high hanging valley, flowing over 365 million year old limestones. At Maligne Canyon, multiple waterfalls, potholes, and outlets of underground springs are preserved from what may well be an old and exhumed cave system. The hike along Maligne Canyon, with the waterfalls, deep chasms and gushing springs is breathtaking. Medicine Lake, Jasper National Park, drains through caves at its base. Farther upstream, the spectacular and unique cave drainage system at the Springs entering Maligne River, Jasper National bottom of Medicine Lake is one of several Park. Spring water flows through a cave system reasons that the United Nations created draining Medicine Lake 16 km away. the UNESCO Canadian Rocky Mountain The water from Medicine Lake drains Parks World Heritage Site. Medicine Lake through an underground cave system rises and falls as much as 19 meters every downstream for 16 kilometres to emerge year due to snowmelt and rainfall raising as a series of springs at the lower end of water levels. At the bottom of the lake, Maligne Canyon just above the Athabasca much like a bathtub at home, are two River valley. drains that try to empty the lake year round. The river valley that exits 2 Rocks, Ridges, and Rivers: Geological Wonders of Banff, Yoho, and Jasper National Parks 2. The immense scale of mountain Mount Borgeau, each on separate thrust building from Mount Norquay Lookout, sheets. Cave and Basin National Historic Banff National Park Site is located at the junction separating My favorite location near Banff two separate thrust sheets. From the townsite is Mount Norquay lookout. viewpoint, you can imagine cold water There is just so much to see from this from the mountain tops across the valley, easy to access location. The view is a percolating down to 3.2 kilometres depth, spectacular panorama across the Front becoming heated by radioactive minerals, Ranges of the Rocky Mountains. and then rising as hot water along The Mount Norquay viewpoint Sulphur Mount Thrust to Cave and Basin gives you a feel for the enormous forces National Historic Site. involved in mountain building. If you What else can you see? The want to feel the tremendous vertical and mountains have been uplifted kilometres. horizontal scale of the mountain building, Now they are being eroded! Consider the you have to go here. You can actually see amount of erosion that has taken place. In how the mountains are stacked against front of you, 4.5 to 7.5 kilometers of one another, like shingles on a roof. sediment has been eroded from the tops You look down on the Bow River, and the valleys of these mountains over where it is cutting across several of those the last 55 to 60 million years. This enormous thrust sheets. You can see amount of material that has been eroded Mount Rundle, Sulphur Mountain and away is just astonishing! View of stacked thrust sheets as seen from Mount Norquay lookout, Banff National Park – Mount Rundle (left), Sulphur Mountain (centre) and the Sundance Range (right). 3. Thermal Springs at Cave and Basin water at its base. Snow melt and National Historic Site, Banff National rainwater on the peaks of nearby Park mountains makes its way to a depth of 3.2 Banff National Park owes its kilometres before being heated and existence to railway workers’ recirculated up a major thrust fault to encountering an open, steaming vent that emerge as hot springs. Water led down to a cavern with a pool of hot temperatures are 27 to 47° C at the 3 Rocks, Ridges, and Rivers: Geological Wonders of Banff, Yoho, and Jasper National Parks surface, varying seasonally and at the spring-water temperatures. Blue-green different springs. coloured cyanobacteria grow in At Cave and Basin National undisturbed thermal pools as does white, Historic Site, enter through the main filamentous bacteria. building to see hot springs pool with glacial till overlain by a layer of travertine 4. Fossils of the Burgess Shale and the flowstone that is more than 1-metre- edge of a continent, Yoho National thick, and which has precipitated over Park? and draped the till. The thermal spring The Burgess Shale fossils provide a waters flow at the contact between the view into life that existed 505 to 510 travertine and the till. The till has been million years ago, after a period called the eroded by the stream flow, whereas acidic Cambrian Explosion. What is so exciting hydrogen sulphide coming out of solution and unique about these soft-bodied fossils from the spring water corrodes the is the preservation of features such as travertine. The two caves and the outside eyes with retinal and brain tissues, livers, collapsed cave formed as a result of hearts, neural tissues, stomachs, and even stream erosion of glacial till and the eggs containing embryos! Many of these travertine dissolution by acid gases. fossils are predecessors to many of the Gypsum crusts coat the travertine, species that exist today, including humans. slowing the rate of acid corrosion. The Burgess Shale was deposited into Eventually, the travertine will be deeper water in front of an extensive, corroded and another cave roof may shallow-water carbonate platform. collapse. Animals having jointed limbs allowing them to move had evolved. Animals could now crawl and swim to eat algae, scavenge dead organisms, and prey on living ones. Several organisms were predators, indicated by shells in gut contents, bite marks, and evolution of hard, defensive spines on prey species. The organisms lived on the sea floor or swam just above it. At that time on land, there was still no animal life, not even plants! Steaming hot spring water in the cave at Cave and Basin National Historic Site, Banff National Park The combination of temperature range and chemistry at the thermal springs have created a unique habitat for the endangered Banff Springs snail. This half-centimetre-long snail lives nowhere else on Earth, thriving on the 30-to-36° C 4 Rocks, Ridges, and Rivers: Geological Wonders of Banff, Yoho, and Jasper National Parks area was located close to and south of the equator at the time. 5. The natural hazard of debris flows at Spiral Tunnels, Yoho National Park Descending down from Kicking Horse Pass, heading westward from the Continental Divide, there are large earthen and concrete works constructed to contain debris flows that affect the railway and highway. These civil- engineering efforts prevent debris flows View to Wapta Mountain from the hiking trail to from burying or washing out the highway Walcott Quarry on Walcott Mountain. or the CPR main line. Debris flows – consisting of liquefied, water-saturated What is now the village of Field in sediment resembling a concrete slurry – Yoho National Park was near the western can be extremely destructive natural edge of North America half a billion years hazards. ago! To the east, towards Lake Louise, Cathedral Mountain and Mount was a shallow-water carbonate platform Stephen, on the south side of the highway, only a few metres deep. At Field, there rise high above the floor of the Kicking was a steep cliff about 200 m high, which Horse River where the valley is less than a directly in front of lived and died the small organisms that were to become the fossils of the Burgess shale. The whole 5 Rocks, Ridges, and Rivers: Geological Wonders of Banff, Yoho, and Jasper National Parks Debris flow chute draining Mount Stephen, Yoho National Park. The chute drains down to cross the Canadian Pacific Railway and Trans-Canada Highway. mountains also trigger debris flows and kilometre wide. The debris flows coming related floods. down Cathedral Gulch are triggered by meltwater that is stored in the glacial 6. The Icefields Parkway along the lakes and meltwater channels on and spine of the Rocky Mountains, Banff within Cathedral Glacier. Glacial lake and Jasper National Park water accumulates behind a ridge of ice at The Icefields Parkway is one of the the front of the glacier during warm most spectacular and scenic highways in periods. Water flows to the base of the ice North America, if not the world, especially through the numerous subglacial on a clear, blue-sky day. meltwater channels and fissures. Water The Icefields Parkway follows the level in the lake continues to rise, ridge or backbone of the Rocky Mountains. The parkway follows the mountain peaks increasing the hydrostatic pressure below of the Main Ranges northward from Lake the glacier front until the ice lifts and Louise to Jasper, along the Continental catastrophically gives way. The lake Divide, passing by as many as a hundred drains as an outburst flood triggering glaciers, many of which are visible from gravity-driven debris flows on the steep the highway. The road passes beside wide slopes. Periods of heavy and steady rains and narrow braided-river floodplains, on the upwind, westward side of the narrow entrenched canyons, alluvial fans, 6 Rocks, Ridges, and Rivers: Geological Wonders of Banff, Yoho, and Jasper National Parks and lakes that have been dammed by dynamic and is changing all the time.