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*The post is my contribution to the #ChemTravelCarnival.  If you’ve written a travelogue (or want to) let me know!*

Geology is applied chemistry, on the million year timescale.  The forces we take advantage of in the lab–acidity, Brownian motion, temperature control–work wonders on the ground beneath our feet, slowly shaping the landscape.

Title - Maligne CanyonLast month I took a trip out to Maligne Canyon (muh-leen) in Jasper National Park [1]. The canyon was one of the highlights of my summer, both because of the beautiful scenery and because walking through the canyon was like looking back through time.

Fig 1 - Maligne Canyon 1st BridgeMuch of the eastern half of Jasper park is built on limestone, layers of calcium carbonate that formed from crushed seashells millions of years into the past.  As the Maligne river flowed over this bedrock, dissolved sulfates and carbon dioxide (as carbonic acid) slowly dissolved the streambed, cutting a series of waterfalls into the ground.

Fig 2 - Maligne Canyon ScouredThe path of the canyon is set by the flow of water, and the water is often caught in small eddy pools.  Over time the constant circular motion erodes the soft rock walls, forming small hollows as the streambed sinks down.  Occasionally the river will change course, and a narrow circular shelf is left behind.

Fig 3 - Maligne GorgeAt points the canyon is at least 40 metres deep, but only a few metres wide.  Moss clings to the walls, living off the spray of water and faint sunlight, while small trees find purchase in the shelves left by eddy currents.  Occasionally a larger tree will fall and be caught by the rock face, hanging suspended.  More rarely a boulder will do the same, forming a natural bridge from one side of the canyon to the other.

Fig 4 - Maligne Rocks are PorousEven without erosion the rock around the canyon is porous, filled with alcoves and tiny caves.  In the largest of the alcoves birds nest, though as they are strictly nocturnal none were visible on my trip.

Fig 5 - Hidden RiversAbout fifteen kilometres upstream a rockslide buries the majority of the Maligne river, and not all paths back to the surface are the same length.  The flow of water increases significantly as we move down the canyon, with dozens of small rivers emerging from the rock [2].

Fig 6 - River GrowsAs it grows wider the river doesn’t cut as deep into rock, and the ground begins to level out.

Fig 7 - River is a TorrentBy the end of the canyon the narrow stream has become a broad river, and all the caves and cliffs are left behind.  Eventually the river will join up with the Athabasca river, winding its way north until it drains into the Arctic Ocean.

Fig 8 - When Calm, water is turquoiseTrue to its glacial origins the Maligne river is bright turquoise, heavy with nanometre stones called rock flour.  Rock flour has its origins in movement of glaciers scraping deep cuts into bedrock [3].  However, that story belongs to another trip.

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[1] Technically the canyon is a gorge.  Yes, that is confusing.

[2] This underground network of caves between Medicine lake and Maligne canyon is almost certainly the most extensive in Jasper, if not the Canadian Rockies.  Unfortunately, all attempts to explore it have met in failure, with even the broadest tunnels quickly ending in cave ins.  Water can seep through the cracks, but little else.

[3] One theory for the formation of Maligne Canyon (shown in the first image above) is that the gorge was originally an underground stream.  Movement of glaciers above wore away ground above, until the water was exposed.

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