Tuesday, August 17, 2010

Goodbye Jasper, Hello Icefields

On the 16th, we broke camp, had breakfast in Jasper, did some errands, and headed south on Route 93, the Icefields Parkway.

Along the way, we stopped at Athabasca Falls to finish our viewing from Friday that had been washed out by the rain.  We learn so much geology every time we step out of the Prius - we'll have to take a course so we can have context for all the bits and pieces we've learned.  We came back to the Falls because we wanted to look more closely at the channel below them. The channel is narrow and cut through closely packed sedimentary layers.  The rock must be pretty hard, because over the years a large volume of water has cut a very well defined channel that shows few signs of erosive rounding or widening.
Channel Below the Falls
One feature, called a pothole, caught our eye, a round tub-like cut in the side of the channelformed by turbulent water.
Pothole
The volume of water that goes through the channel becomes the wide Athabasca River only 200 yards beyond the Falls.  The river originates in the glaciers a few tens of miles to the south, resulting in a heavy load of suspended silt.  It is this silt that gives the rivers and lakes in the Canadian Rockies their shades of turquoise.
Athabasca River Just Below Athabasca Falls
The Athabasca River has its headwaters in the glaciers  It travels through Alberta before draining into the Peace-Athabasca Delta and Lake Athabasca on the Alberta-Saskatchewan border and thence to the Arctic Ocean via Great Slave Lake and the Mackenzie River.

Then it was down the road for 50 miles or so to the Athabasca Glacier.  This is the glacier that flows down from the Columbia Icefields to about a mile from the highway.  The Icefields, above and behind the glacier, are about 125 square miles of glacial ice as much as 1100 feet thick.  170 years ago, the glacier stretched down to the parking lot, but in receding has lost about 60% of its 1840s volume.
Athabasca Glacier Seen From the Icefields Visitors Center
Looking across the Athabasca Glacier toward the Columbia Icefields
We went about two-thirds of the way up the glacier on wonderful big buses, with 30 minutes actually on the glacier - much closer views of the steps in the glacier (where the glacier flows over especially hard rock) and the lip of the Columbia Icefields.
 Just to show we both were there
An unexpected delight were the views from our glacial bus stop of the Andromeda Glacier. That glacier has carved a huge cirque into its mountain.
Andromeda Glacier
One should spend as much time in the visitors center as on the tour in order to comprehend the magnitude of the Athabasca Glacier and the Columbia Icefields that feed it.
Mt. Athabasca from the Visitors Center
Finally, we left the Icefields and drove to Lake Louise, coming through thicker and thicker haze.  We are told that there are very bad forest fires in central British Columbia and the smoke has drifted through the passes.  The fires are a long way from containment, and we wonder how much of the mountains in Banff National Park we'll be able to see.