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NATURE
· Fastest-growing Mountains in the World
FIRST PEOPLES
· The Champagne and Aishihik First Nations
HISTORY
· A Dazzling Landscape
This is a link to a map of the mountains of British Columbia and a close up of the Tatshenshini.

FOCUS  Tatshenshini

Fastest-growing Mountains in the World
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This is a photograph of the icy peak of Mt. Fairweather against a blue sky.
Mount Fairweather, at 4,663 metres the highest peak in British Columbia, is close to the BC-Alaska boundary. David Fraser.
The St. Elias mountain range, along the border of British Columbia, Alaska and the Yukon, is an area of superlatives — it contains the largest nonpolar icefield in the world, the highest number of surging glaciers, the most seismically active mountains on earth, the largest protected area on the planet, and the highest, youngest and fastest-growing peaks in Canada.

These mountains began as an area of volcanoes about 15 million years ago, when the floor of the Pacific Ocean started sinking beneath the continental margin near coastal Alaska. With this uplifting, faulting and folding of the earth's crust, the mountains now known as the St. Elias range were born. About 100,000 years ago, the growth surged when a chunk of crust, dislodged from farther south, crashed into the coast of western North America. This piece of crust, called the Yakutat Terrane, is about 200 kilometres wide, 600 kilometres long and 13 kilometres thick. Pushed by unimaginable forces like a wedge under the St. Elias Mountains, it is the main cause for the rapid rise of the range.

The fastest-rising land in this area is growing at about 4 centimetres per year, about as fast as your fingernails grow. But the growth is not steady. The mountains rise, shudder by shudder, resulting in one of the most earthquake-prone areas on earth. On average, three earthquakes a day rock the earth here. In 1899 one earthquake raised the ground over 10 metres in less than two minutes — it's just as well your fingernails don't grow like this!

Recent changes in climate have sped the melt of the glaciers of the St. Elias Mountains. The reduced pressure on the earth's crust may contribute to the rapid rise of these dynamic mountains.

The St. Elias Mountains are the youngest in Canada. Mount Fairweather. David Fraser.
This is a photograph of Mt. Fairweather in the St. Elias range, with a Bald Eagle and layers of cloud in the foreground.

The St. Elias Mountains rise from the shore of the northeast Pacific, blocking the wet oceanic air masses as they blow eastward. They force this air upwards, cooling it and trapping heavy precipitation, particularly winter snow. Snow accumulations of 7 metres or more are common.

These enormous snow loads feed the formation of the icefields. Year after year new layers of snow bury and compress the previous layers, forming ice. This increasing weight pushes the ice outwards and eventually down the sides of the mountains. Ice masses that flow downhill are called glaciers. Ice masses that form between mountain peaks and flow in more than one direction are called icefields.

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