Ron and I have driven past the entry to this park many times on our travels through the Rockies but we've never stopped. Don't know why. I guess you never hear much about it. We were in for a treat.
When we saw the canyon for the first time we were really impressed. It's deep and not very wide. It's easy to see why it was called "Black". Little sunlight reaches the bottom and in the shadows it appears dark and forboding.
The south canyon walls have a slightly less steep slope than the often near vertical north canyon walls. The south side of the canyon faces north and retains moisture that seeps through the rock and erodes that slope at a slightly faster rate than the north canyon wall. Interesting, right? No evidence of peoples living in the canyon has ever been found. It's steep, narrow, rugged terrain is not inviting as a place to live.
Can you see the vertical pink stripes in the photo? Over a billion years ago molten rock was squeezed into the fissures in the dark gneiss (say like "nice") rock. This igneous (rock formed under pressure) light colored intrusion is called a Pegamite Dike. It is a harder rock than the gneiss into which it intrudes and erodes more slowly leaving pink fin-like formations.
The same process of molten rock intruding into fissures created "The Painted Wall" over a billion years ago. It's the tallest cliff in Colorado at 2300'.
In the park brochure they talk about the anatomy of three canyons: Black Canyon, Yosemite, and the Grand Canyon. The Black Canyon of the Gunnison is the result of hard rock being uplifted then cut through by fast moving water carrying abrasive debris. In just 48 miles the Black Canyon of the Gunnison loses more elevation than the Mississippi River does from Minneapolis to the Gulf of Mexico. The river drops an average of 96' per mile in the park and drops 480' in one two-mile section. The power of this fast falling river has enabled it to carve this deep canyon through the hard crystalline rock of the Gunnison Uplift over two million years.
Yosemite was carved by the Merced River and later by glaciers creating the U-shaped valley that is 7 miles long and in many places a mile wide. The Merced River was a meandering river, as it is today, until uplift and westward tilting of the Sierra Nevada. At that point, 3 million years ago, it became a raging debris carrying river capable of carving a 3,000' V-shaped valley through the hard granite. 250,000 years ago glaciers added the final touch by carving the U-shaped valley we see today.
The Grand Canyon has eroded over a period of time three times that of the Black Canyon. Its soft, Colorado river-carved rock has been shaped by erosion. It is a mile deep, 4-18 miles wide and 217 miles long. The many shapes of the canyon are the result of how its varied types of rock have resisted erosion. Harder rocks have eroded to cliffs and softer rocks have eroded to slopes. Different minerals (most with iron) have given the Grand Canyon its magnificent colors.
This national park is all about knowledge. The rangers are there to teach you about the canyon, the wildlife, the night skies, and the day sky. When we arrived at the visitor center a ranger had a solar telescope set up so we could observe the sun. You could see the gaseous flares from the sun. Very fun.
At night we attended a great program on the night skies of Black Canyon of the Gunnison. This was different from the one we had attended at Bryce. We learned about star formation, black holes, star death (like the supernova we had seen at Bryce) and galaxies. We got to look closely at the moon and Saturn.
It was fun for Ally to attend the program with Bowen and Cy, another camper.
We saw small beautiful critters...
...cute, cuddly critters...
...creepy critters...
...and we saw what Ally wants for her 18th birthday. As her grandparents we totally support this idea. We'll have a driver and will ride in style! Plan ahead, Dad!
Black Canyon of the Gunnison was one of our surprise parks. We learned a lot, had a lot of fun, and enjoyed all the great programs offered here.
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