This past Sunday, Remembrance Day, was an unseasonably warm day of 18 degrees Celsius in Toronto–a record breaker. To take advantage of the warmth, in the afternoon we went to The Evergreen Brick Works. We walked along the railroad tracks, past milkweed and thistles and a disheartening array of tires dumped there.
At the Brick Works, we found that many people had the same idea as us and were strolling around the grounds and enjoying the day. The colours are now soft—mostly muted browns, beiges, yellows and greens.
At the North Slope of this once quarry was a Toronto Parks and Recreation sign noting the geology of the slope that reveals evidence of several ages of ice alternating with warm periods. The sign reads as follows:
-The North Slope is a geological feature of international significance.
-Professor A. P. Coleman, a world-renowned Toronto geologist, first identified the significance of this slope in 1894.
-This site was one of the first in the world to reveal a rare sequence of climate change. The deposits here indicate a glacial episode, followed by a period of climate slightly warmer than today’s, followed by another glacial episode, and lastly the climate of today.
There’s also a drawing on the sign indicating the age of the deposits that make up the North Slope. These range from the bedrock which is 448 million years old, to deposits over 135,000 years old and lastly to the most recent ones in the top layer which accumulated 13,000 – 50,000 years ago. I like to contemplate life from this other perspective—it certainly helps with a feeling a humility.
I’ll be adding many more posts about my time in the Canadian Rockies. I think of the mountains every day and miss them. Meanwhile, in Toronto it’s autumn. The turning leaves are beautiful and bring me solace as I travel around the city.
Today, it was very warm and sunny. I returned to the Brick Works—passing milkweed in luminous seed by the railway tracks. Other people strolled about on this lovely day and I spoke to a woman who had seen eastern bluebirds at the Brick Works yesterday.
I saw and heard red winged blackbirds, chickadees and mallards. Also, I heard what I believe were finches or warblers of some sort.
And at the Brick Works, I read a sign about the geology of the land here. It was good to relate my new found interest to the land close to home. And to contemplate, as I had in the west, that we live off of life much older than ourselves.
The sign reads:
The rock of this west quarry wall is shale with harder layers of silty limestone. It originated in a tropical sea around 448 million years ago. If you look closely you may see some fossils…The presence of easily accessible shale made this site valuable as a brick making operation.
I’ve mentioned before that being in the Rockies awakened in me an interest in geology and earth history. As I travelled, I wanted to learn how the mountains, lakes and canyons were formed. Here’s a small bit of what I’ve gathered about Lake Louise and Johnston Canyon.
Near the end of our travels, I bought a book to help in my learning called How Old is that Mountain by Chris Yorath. From that book I’ve learned that Lake Louise may be a tarn. And for those of you who have never heard of a tarn, as I had not until a short while ago, it’s a lake that has formed at the base of a steeply walled recess—shaped like a deep bowl—on the side of a mountain. These deep recesses are called cirques and are formed by mountain glaciers eroding the mountain’s rock.
In the case of Lake Louise, it’s possible that when the glacier on Mt. Victoria was much larger it carved Lake Louise’s basin. This may have happened around 25,000 years ago.
Here, the huge lengths of time geology deals with need to be put in terms that our minds can comprehend. In geological terms, 25,000 years ago is very recent. For example, scientists estimate that the earth was formed around four and a half billion years ago and that our human ancestors arrived around 3 million years ago.
To help us, Chris Yorath includes the following analogy. If we imagine the entire history of the earth as a 24 hour clock, the creation of the planet would be at midnight—00:00. And the appearance of humans would not be until well past 23:00 hours, at one minute and a few seconds before the following midnight. This has certainly given me pause for reflection and helps me grasp that Lake Louise was formed in recent times.
Back to her now. I learned, from information in Banff National Park that the beautiful green blue of Lake Louise and other Rocky Mountain lakes arises in large part from rock flour. That is, from fine particles of sediment washing down from the mountains into the lake. This was visible to us at the end of the lake closest to the Plain of Six Glaciers hike.
In the case of Johnston Canyon, Yorath reports that according to Parks Canada the canyon was created around 8,000 years ago. At that time, a landslide that brought masses of rock down from a nearby mountain diverted Johnston Creek from its path. Then, over time, the canyon, which is 200 metres deep, was carved out.
I alternate between contemplating geological and human time scales. Either way, while I was in the presence of the mountains, lakes and canyons, I felt something very old, compared to my life, surrounding me. Being part of nature in that way, experiencing that sense of time and change, was life giving. Because of that, I hope to always draw on the memories of my time in the Rockies and to return to them again.
My recent trip to the Canadian Rockies ignited in me an interest in geology. I looked at the mountains and wanted to know what had formed them. I’ve bought a few beginners’ books on geology and the history of the earth and am reading them with great fascination. This past weekend, when I was in Algonquin Park in Ontario, I was also aware of the boulders and outcroppings of rock and am learning a bit about how these were formed.
Contemplating the incomprehensible sweep of billions of years of creation and change that the earth has gone through has brought me some surprising peace of mind. I’ve learned that the rock in the mountains were once under sea, something I dimly recall hearing about before, but not paying any attention to. In some of the rock, the remains of shells are found. This has gotten me thinking about the oneness of life, in a literal sense. What we now see and experience as solid mass rising above us, was once on the bottom of tropical seas. Water, ice, fire, land and movement shaped the western mountains and the boulders in the east. And my existence here in this tiny speck of time is amazing seen in the context of the vast billions of years of earth’s history.
Many of us are afflicted or in some anguish at different times of our lives and perhaps unable to get outside of our own suffering. Despite this, I have begun wondering if the felt sense of the earth’s awesome history might also help other people feel less alienated from their surroundings, as it has for me. I don’t know the answer to this. But what I’m discovering is that the study of science at a beginner’s level is fascinating and quite do-able and, for me, calming.