November 14, 2020
How do I explain this? I think we are all familiar with this scene from The Raiders Of The Lost Arc. This image comes to my mind every time I choose to do something the hard way. And so I thought of this scene today.
I will explain. First, some background.
Horseshoe Bend is a horseshoe-shaped incised meander of the Colorado River located near the town of Page, Arizona. It is also referred to as the "east rim of the Grand Canyon."
It is a superb example of a entrenched meander. Six million years ago, the region around Horseshoe Bend was much closer to sea level, and the Colorado River was a meandering river with a nearly level floodplain. Between six and five million years ago, the region began to be uplifted. This trapped the Colorado River in its bed, and the river rapidly cut downwards to produce Horseshoe Bend as we see it today.
The cause of this uplift is still a matter of research. One hypothesis is that uplift was a result of delamination, where the lowest layer of the North American tectonic plate below the Colorado Plateau detached and sank into the underlying mantle. This would have allowed hotter rock from the asthenosphere, the part of the earth's mantle that underlies its tectonic plates, to rise and lift the overlying crust. Another possibility is that the uplift was the result of heating at the base of the crust. This transformed the lowest crustal rock from eclogite, a relatively dense rock to garnet granulite, which is significantly less dense. This would have produced the buoyant forces needed to uplift the region.
Whatever the cause of the uplift, it resulted in the erosion of up to a mile of overlying sediments from the eastern Grand Canyon. This exposed the Navajo Sandstone, the surface rock found throughout the Horseshoe Bend area, which also forms the entire depth of the canyon walls of the Grand Canyon at Horseshoe Bend. This sandstone is notable for its crossbedding and iron concretions.
It is likely that the Colorado River will eventually cut through the neck of the bend, producing a natural bridge like those found at Natural Bridges National Monument in Utah. The river will then abandon Horseshoe Bend, leaving a cutoff meander.
Here is a popular photo of Horseshoe Bend.
Pretty, right? I take photos like this one as a challenge - can I take one as pretty or even better, take a better photo? One caveat - it is pretty clear to me that this photo was Photoshopped. The colors are just too rich. I could be wrong. I’m not against Photoshopping with the understanding that it gives you an image that you couldn’t get naturally.
So I get to the Horseshoe Bend Visitor Center, pay my $19, park my car and head out to my challenge. The path is about 0.5 miles and I walk with a few hundred of my new friends. Toward the end of the path there is a collection of people taking photos. I figure there is no way the above photo was taken near the path so I veer off and spend the next two hours walking through rock formations trying to get the right angle -- without falling over the edge. I got some fun shots of the rock formations while i was doing this.
Then I found a place to get a food shot - but I couldn't quite get the whole view into the image. Close but no cigar. So I continued to wander.
I was as close to the edge as I could be for this photo.
At this point, I headed back to where all the people were at the "lookout point." I decided to take some photos from there -- resigned that I would not get to challenge the photo I found on the Internet.
Here's what I got.
Maybe not quite as good as what I had found on the Internet but perhaps with a little Photoshopping I could get the richer colors? I had learned my lesson thought; first go to where ever one is taking photos and start there. At least I got some decent photos while I was walking around!