The First Cordillera Crossing: Field Excursion A 0X at the 1972 Montréal IGC

2022 Anniversaries in the History of Canadian Science and Technology

First posted Friday, July 22, 2022 / Yom shishi, 23 Tammuz, 5782

By David Orenstein, Emeritus, Danforth CTI

david.orenstein@alumni.utoronto.ca

Back on Canada Day I gave an overview of “the Field Excursions of the 24^th International Geological Congress, held in Montréal in 1972”.

Therein, I duly noted that “[t]he first planned excursion started on the evening of Saturday, July 22, 1972, when excursionists gathered at their Calgary hotel”.

That’s exactly fifty years ago today: the precise semi-centennial!

That was “Excursion AX-01, ‘Structural Style of Southern Canadian Cordillera, with Emphasis on Core Zone of Eastern Fold Belt’. The excursionists were expected… to get in an early start on the 23^rd, to go over the Rocky Mountains by bus. There would be helicopter side trips to some of the more inaccessible locations high up in the mountains. They reached Vancouver, BC, on Friday, August 4, with a restful night at their hotel awaiting them.”

There were four leaders for this Excursion: R.B. Campbell, J.E. Reesor, and J.O. Wheeler, were all of the Geological Survey of Canada.

The fourth was McGill University’s Eric W. Mountjoy (1931-2010). “He was a Fellow of the Royal Society of Canada and he was awarded the Logan Medal by the Geological Association of Canada, the Douglas Medal by the Canadian Society of Petroleum Geologists, and the Pettijohn Medal by the Society for Sedimentary Geology.”

Day 1: Sunday, July 23, 1972

So, early Sunday morning the bus picked them up at their hotel to drive 14.5 miles / 23.2 kilometres west to, Stop 1-1, the “Western Edge of the Plains…. This stop provides a view westward across the Foothills to the Front Ranges of the Rocky Mountains.”

There would be fourteen more stops that day where the last stop, 1-15, was at Golden, B.C. There, at 154.2 mi / 246.7 km into their expedition, they viewed the Rocky Mountain Trench from the top of a hill overlooking the town of Golden: “Highly cleaved McKay Group pelites, complexly folded in a synclinorium from the floor of the Trench.”

Previously that day there had been three stops at or near the Great Continental Divide, which in this section coincides with the Alberta / British Columbia provincial border.

Stop 1-8 (110.0 mi., 176.0 km) near the famous tourist attraction of Lake Louise, Alberta, allowed a view of the “Miette Group Slates at Junction of Banff-Jasper Highway [a North-South rptue in Alberta, just East of the Divide] and the Trans-Canada Highway.” Cleaved dark-gray rocks “illustrate a greater degree of tectonic deformation within these strata in contrast with that of younger rocks.”

Stop 1-9 (113.7 mi., 181.9 km) was “[n]earby… the Great Divide and the Alberta-British Columbia boundary at the summit (5339 feet, 1625 m) of the Kicking Horse Pass. The transcontinental railroad reached this point in 1883 and was completed from coast to coast in 1885.” Thus, allowing Prince Peter Kropotkin and the many other BAAS Excursionists to travel by train all the way from Toronto to Vancouver in 1897, only twelve years later.

Here, “[o]utcrops of white and pink quartzite with … Gog Group” (lower Cambrian) argillite. The “crossbedding indicates deposition by currents flowing form northeast to southwest.” Fossil fragments of the Early Cambrian trilobite genus Olenellus were to be found “in the upper… Gog limestone beds”.

Pressing further into B.C., along a stretch of 1.6 mi. / 2.6 km (aka Stop 1-10), “[t]he route continued up section to the massive carbonates of the Middle Cambrian Eldon Formation. Down the steep hill to the Spiral Tunnels Lookout… down section through nearly flat-lying… Middle Cambrian” carbonate strata “to the Lower Cambrian Gob quartzites. A prominent west-side down normal fault… can be observed nearby.”

After Golden, they pushed on westward to Revelstoke, British Columbia, where they bedded down for the night.

Day 2: Monday, July 24, 1972

Revelstoke would serve as the base for many of the excursion’s operations.

For example, it was from Revelstoke that they flew by helicopter to Invermere, B.C., on Monday, July 24, 1972.

But that’s another story!

Links

A) Related CSTHA Blog Posts:

– Peter Krpotkin Coming to 1897 Toronto BAAS, July 21, 2022

https://cstha-ahstc.ca/2022/07/21/prince-peter-kropotkin-anarchist-leader-and-geographer/

– 1972 IGC Field Excursions, July 1, 2022.

https://cstha-ahstc.ca/2022/07/01/happy-canada-day-joyeux-fete-du-canada-2022/

B) Itinerary Links: