It is 309 miles from Trail Canyon to Grand Canyon and much of it is the usual wide open spaces. But some of it is the most iconic scenery in the USA.
Our first glimpse of Monument Valley gave us a distant view of the real stars of countless westerns. (If you didn’t like the movie you could always watch the scenery!)
A distant view of Monument Valley
But before we got any closer we saw the sign to the San Juan River Goosenecks which I remembered seeing in my copy of Arthur Holmes “Physical Geology” when I was a student. Not far off the main road we came to a car park, looked over the wall and saw the most spectacular incised meanders I know of.
Goosenecks of the San Juan River
As you can see we are on a plateau and all the topography is below – you look down at the cliffs. The river is about 1000 feet below and the rocks are of Carboniferous age.
The incised meanders of the San Juan river
One presumes that the river and the meanders were there before the uplift of the Colorado Plateau started and the rate of erosion downwards of the river was similar to the rate of uplift the plateau. The inner gorge is in limestone which seems to be more able to preserve cliffs than the sandstone and shale of the higher slopes of the gorge.
Of course such a resource cannot be allowed to go to waste and you can hire rafts and canoes to drift down the river.
Drifting through the Goosenecks
Not all the rocks in the area are flat-lying – near the rock called Mexican Hat there is a sudden dip in the sediments.
Mexican Hat and some dipping sediments
The monocline is thought to be due to vertical movements.
But not very much further and we are in Monument Valley.
The road to Monument Valley
Monument Valley contains many buttes and mesas. A mesa is a large butte. Here is a photo of an isolated butte.
A butte in Monument Valley. The butte is probably in Utah, I was in Arizona, or more particularly, in the Visitor Centre of the Navaho Reservation. Reservations are Federal land and completely ignore state boundaries.
The impressive bit in the middle is the butte with its vertical sides. It sits on its pediment which is the slope leading up to the cliffs. And in the foreground is the pediplain. And, strangely enough, most of the sculpture of this landscape is due to the action of water, even if we are in a desert. This is not the place to discuss desert erosion features but a web search will produce all you could ever want to know.
The shapes in Monument Valley are impressive but it is their combination with the rust red of the rocks and the blue of the sky which one remembers.
Monument Valley
Erosion continues apace in the valley and landslides at the bases of buttes are commonly seen. Many of the most spectacular buttes look like skeletons of a once more considerable body.
Much eroded buttes, Monument Valley
After our stop in the Visitor Centre of the Navaho Reservation, which gives a Navaho perspective on the settlement of the area – they feel aggrieved, with good reason, – we pressed on towards the Grand Canyon.
We were crossing a featureless part of the route when we saw a sign pointing us to an Indian Market. And a small sign saying Little Colorado Gorge. The Indian Market was lots of stalls selling all the usual stuff – many of them empty as the tourist season was not really started – in a large car park. And the edge of the car park was the Little Colorado Gorge. Select the correct gear when leaving.
The edge of the Little Colorado Gorge
You look over the edge and it just keeps on going down. The rock types are less spectacular than the Grand Canyon but the depths are almost as great.
Looking down a gulley into the Little Colorado Gorge
So this gave us an introduction to the glories of the Grand Canyon which will be the subject of the next post.
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