A clearing storm in Carbon Canyon, a tributary to the Grand Canyon |
The Desert View Watchtower on the eastern edge of the South Rim of Grand Canyon. |
Mather Point, possibly. I didn't label this one! |
The North Rim is distinctly different. A thousand feet higher than the South Rim, it is covered with an extensive cool forest of fir and ponderosa. It's lonelier, with a single resort, a small camper store and a campground (check out the excellent Geogypsy Traveler blog for the perspectives of a North Rim ranger). No matter where I am on the North Rim, it feels more wild. It's one of my most cherished places in the world. But I can't pick out a single spot that I've stood on that set it apart from other areas of the canyon.
There are the archaeological sites. People have lived on and in the Grand Canyon for more than 4,000 years, and have left behind intriguing clues about their lives and beliefs, including the split-twig figurines and multitudes of petroglyphs and pictographs. Had I not ended up a geologist, I would most certainly have followed archaeology as a career. The Grand Canyon has some great archaeology, but I couldn't pick a single spot that represents all the canyon means to me.
It is at this point that river-runners first encounter the Granite Gorge, the Inner Canyon of the Grand Canyon. The rocks are schist and gneiss 1.7 billion years old that formed in the roots of a long-gone mountain range that until recently was hidden in the deep crust of the lithosphere. Only in the last five or six million years has the Colorado River exposed these rocks to view. It was near this spot that John Wesley Powell wrote his immortal words about the Grand Canyon: "We are now ready to start on our way down the Great Unknown...We are three quarters of a mile in the depths of the earth...We have an unknown distance yet to run, an unknown river yet to explore. What falls there are, we know not; what rocks beset the channel, we know not; what walls rise over the river, we know not."
The Great Unconformity separates these ancient rocks from the only somewhat younger rocks of the Grand Canyon Supergroup (the reddish sediments on the right in the picture below). The Supergroup is a group of late Proterozoic sediments that are three times as thick as the main sequence of Paleozoic rocks that make the upper 4,000 feet of the Grand Canyon cliffs. They were faulted, tilted, eroded, and ultimately buried by the advancing Cambrian sea of 515 million years ago. It may be the most famous unconformity on the planet.
This was the spot where I became a geologist.
I returned to Hance Rapids last summer for the first time in thirty years, only this time I came by raft rather than by foot. I am still processing that journey in my mind, but I already know that it was one of the most significant events in my life. I became aware of the fragile nature of life, first among the plants and animals in this challenging environment, but also of my own. Aside from the profound risk of driving a car every day, I came the closest I've ever been to realizing the possibility of death when I was dumped into the near freezing water and rode the toughest rapid for more than a quarter of a mile. We went over more than 150 rapids in seventeen days, and Hance was the first of the monster rapids, rated 8 or 9 on a scale of 10.
Some pictures surfaced a couple of years ago on my Facebook page of that first profound adventure that I had in 1976. It's remarkable how little the river and the rocks have changed, but I realized how much has changed in our understanding of how the rocks of the canyon accumulated, and how the canyon itself came into being. Plate tectonics had been accepted only a few years prior to my arrival in the canyon, and the tectonic history was only just then getting worked out. Parts of the story are still mysterious.
I also realize the massive changes in my own life since then. Back then, there was a dedicated geology professor discussing the history of the canyon, and a young man making life-changing decisions in the professor's class. The young man had not yet married, there were no children in his life, he had not earned a living on his own. He was just starting out.
Today, my kids are grown, I get awards for longevity at my job, and I'm closer to the end of my career than I am to its beginning. I am a teacher now, but I continue to be a student as well, seeking out new places, and revisiting the old ones from the past for continuing enlightenment. The canyon will continue to exist, changed only in a few ways during my tenure on the planet. It knows or cares little of the latest life form that scrabbles about its surface, and it will shrug off the gigantic reservoirs we've constructed to try and control the river.
The canyon is an incredible place. It gives us perspective in so many ways, and that's why it ended up as number two on the list of the most incredible places I've ever stood.
Just who is that thin person in the yellow jacket?? |
3 comments:
You have a wonderful relationship with the Canyon in all its glory, Garry. It's a pleasure to read about your passion for geology in this fascinating area. I am now wondering... what could top this?
Grand Canyon has a profound affect on all who experience it, and from many vantages be it the depths or the rim. Certainly can understand why it's on this list, but really, #2.
And I figured the great unconformity as #1 on your list. looks like reading your blogs for 2 years isn't enough yet.
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