A CITY BUILT ON SALT

Entrada Sandstone Fins at Fiery Furnace, Arches National Park. Salt made it happen!

Moab was an ancient kingdom situated along the East shore of the Dead Sea, a lake of salty brine in Palestine. But it is not the subject of this post. We are dealing here with a more recently founded place, settled by Mormons at the outset, as so many other cities in the Four-corners region. It is the only city in Utah placed in the Colorado valley. What has this latter-day Moab, a tourist center, got to do with salt, you may well ask?

In fact, salt lies at the bottom of Moab's whole existence, in many respects. You may be surprised to hear that the town is situated in the middle of a piece of real estate, with a a radius of some 150 kilometers, which harbors one of the biggest deposits of mineral salt in the world. Covered by sandstone, there lies resting, some 150 meters below the surface, a layer of that crystalline medium almost TWO KILOMETERS thick. This is the Paradox Basin we are talking about here, stretching South almost to the border with New Mexico, and encompassing both Arches and Canyonlands National Parks.

A salt layer of such enormity has some peculiar geologic properties, which were discovered by the experts only recently. You will find no mentioning of salt in early brochures of the National Park Service (Yes, I am still safeguarding the booklets we received upon our visits more than 30 years ago), whereas the modern brochures all take care to explain the role salt has played in shaping the environment hereabouts.

Moab Valley. Created by salt!

Over the eons, the Earth crust is subjected to a lot of pressures, as tectonic plates shift, collide and are shoved underneath each other. This has affected the gigantic layer of salt mightily. Salt is of a consistency in between rock and sirup, a geologic toothpaste so to speak. When horizontal pressure is applied to it, it tends to swell upwards, just like – well – the toothpaste in the tube you are squeezing in the morning, just at a greater, geologic scale.

Huge domes of salt have been created this way, hidden under their roof of sandstone. But the latter is not as plastic as salt, so when lifted up by the rising salt dome, it fractures into fissures. Eventually, the sandstone cupola (that can have a radius of several kilometers) breaks up into upward standing slates and would to us, flying above it, look a bit like enormous stones fitted into a valve or valved bridge.

As water starts siphoning through all those cracks between the vertical slates, the salt beneath starts dissolving and the bubble sinks back to itself. In many cases, this process comes to a halt, when the overlaying crust of sandstone gets back to its horizontal position. However, the cracks have remained and erosion continues. Eventually, the slates´sides will be shaved off and they start standing freely as so called Fins, as in the title picture. Over time, some of them are ground down completely and the remaining getting sanded down by the wind into sleeker and sleeker shapes. Holes start to appear in those fins and – Voilá! – an Arch is born. Delicate Arch is a good example of just one of many on the plateau.

Balanced Rock, Arches. La Sal mountains in background

But those arches don't hold forever either. As the hole under the arch gets bigger, the bridge above eventually collapses and only free standing hoodoos are left. Balanced Rock is a good example of this. Even those hoodoos are getting ground down over the year millions and the end result is a reasonably level plain of sandstone, when entropy has won the fight at long last. Look at the little stubble to the right of Balanced Rock. This is the fundament of a smaller balanced rock that fell down in the early 1970s. Precious little is left and soon what is left will have melted down to a heap of sand.

We said above that the salt bubble usually stops sinking back when the upper layer retains its roughly horizontal  position. But there are exceptions. If the original fissures are large and remain to feed the underlying salt with water even then, the dissolving continues and the sandstone layer eventually is hanging freely over a void. Of course, it collapses soon after and the result can sometimes be a huge valley, several kilometers long and up to one kilometer broad. These are the so called Salt Valleys. Moab Valley, which you can see above, is an example of such a construct.

When you journey to Moab for the first time, you may believe that the Valley has been shaped by the Colorado River, like so many canyons in the area. It is true that the Colorado runs through it. But it does so at an angle. The aerial view shown below demonstrates, how it has cut its way through the sandstone layer, coming from Colorado in the West and is now flowing into Moab Valley, which has been shaped by other forces. The valley is seen in green, with the town in the lower part of that green.

Aerial view of the Colorado entering Moab Valley       Source: Grand County, Utah

This takes care of our usual geologic outburst. Time to get back to the story we have to tell. You may recall that we had an intermission after Delicate Arch in the previous blog (God's Delicate Fingers). The last big iconic experience left to explore in Arches National Park is the fabulous landscape called Devil's Garden. In these surroundings we really can get our fill of Sandstone Fins, since the whole area is just built up by them.

Besides the fins, there are also numerous arches to admire, I count at least ten of them. However, as usual, we concentrate on the most scenic ones, Landscape Arch and Double O Arch. To see them both, you have to take a hike of some 5 hours (roundtrip), but it is worth it. So let's get on with it and tell about the trail's wonders as we go.

Devil's Garden Trailhead, Arches. La Sal mountains in the background

The trail starts in a cosy area, where Alice and I had been camping, back in 1980, so this is well treaded terrain for me. As you can see, visitors are being lured into the hike by a spacious path, which actually continues all the way up to Landscape Arch. But soon you come to a tight passage between cliffs glowing in intensive red in the shade. This is a foreboding of things to come, even if the terrain thereafter is widening again.

Sandstone Glow, Devil's Garden, Arches

But not to worry, the path is wide, the air is clear and the number of co-hikers is far from that on the way to Delicate Arch. This is a hike for aficionados, not for the creti and pleti among tourists!

Looking back at the "Narrows". Trail on upper right

It takes just about half an hour's walk to come to the main attraction of this hike, Landscape Arch. This wonder of slimness is said to be the longest natural bridge in the world. Looking at it, high above your head, and thinned out to almost nothing, you wonder how it can hold together at all. But hold together it does. In the old days, when I was young, I had climbed up there and treaded across – can you believe it? I have to say that it was kind of a balancing act in places, with the bridge not even granting you a meter of plane surface to cling to with your sandals.

Nowadays you are completely forbidden to repeat this act – not that I had thought of doing it again! You can't even go near the Arch anymore, not to speak of rambling under it to admire its span. There is now a only a fenced-in path at a distance, allowing you to inspect it without getting too close.

Fenced in Trail below Landscape Arch

How come that this most enticing bow of them all has been put completely off limits? There are ecological and safety reasons for it. There is a lot of sandy soil in the area; if left in peace, it is gradually gaining a fragile cover of vegetation, consisting of a very rare cohabitation of fungus, algae and lichen, found nowhere else in the world. Trampling the soil with your feet is destroying it for a hundred years. So better leave it alone!

The safety reason is less subtle: In 1991, a slab of rock the size of a large bus was falling of the Arch with a tremendous tremble and noise. The few lucky enough to see it reported that they feared the whole structure to come down. No one was hiking below or on the spider-thin bow just then, so no deadly accidents to report here, I am afraid. But it woke up the authorities and, ever since, access to the Arch is strictly forbidden. Will the Arch last throughout my lifetime? I doubt it. It really looks dangerously slim to me now; don't you agree?

Landscape Arch, Arches. The slimmest of the slim, but also the longest in the world

But we have still some challenges ahead of us, even if of smaller magnitude! When leaving the Arch, you start treading on uncharted terrain, so to speak. The National Park authorities characterize the continuing hike as "primitive trail"; in fact, there is no trail to speak of at all, just a few small stones lumped together here and there to show you where you are supposed to take a new direction.

The trail starts with a steep incline, where you have to climb one of the many Fins adorning the environment here. They are not as fine limbed as the ones you see in the title picture, more like whales with broad shoulders, but with VERY STEEP SIDES to climb and descend, which makes some awkward going forward now and then. The picture shows this first ascent. Fortunately it will dissuade any disabled old geezer to dare continue, even if I myself did not show any hesitance at that moment. The climb does not look very arduous from above, where I was standing, but the upward slope is actually rather pronounced. In the far back, you can see once again the "narrows" that started the whole exercise.

Arduous start of the "Primitive Trail"

After this first heart beater you arrive at a plateau where the view is wide and the "whale fins" spaciously laid out. The trail (as far as you can discern it) meanders its way alongside the fins and sometimes crosses over them. I have said it already, but let me re-emphasize that their flanks looked easy enough to access, seen from a distance, but arduous enough once you got close and had to do the real climbing or descending. Still, there were huge rewards awaiting you, once on top. The view was exhilarating from up there. I think the picture here exemplifies both the exhilarating views and the troubles of getting up or down the fins.

On top of a "whale fin". Tavaputs Plateau on the horizon

I chose this picture deliberately, among many fine ones taken on the fins, since it shows where Arches National Park (as well as the Paradox Basin) reaches its end towards the North. Let your eyes, after lingering on and admiring the multitude of red colored fins, sweep like an eagle towards the far horizon. There reign the ponderous cliffs of a plateau which is already known to you. Naught else but the high plateau of the Tavaputs do we rediscover here, known to us since the post Devil's Due.

I have to admit that I fell in love with the fins and the marvelous views they had to offer. Luckily, a fellow traveller was kind enough to take my picture, when I was standing on my absolute favorite, with red cumuli all around me and the La Sal mountains glistening in the background against an azure sky.

Emil Ems on Sandstone Fin in Devil's Garden, Arches. La Sal mountains in background

I had to almost tear myself away from climbing up and down those "whales". It was getting afternoon and time to come to the final goal of the hike, the Double O Arch. This is a funny name and you only get to grips with it when you have seen the object in question. It is a wondrous construct of red stone, fashioned a bit like an antique Greek "Lyra", at least if seen from the backside. It looks not quite as imposing when you approach it on the trail. You simply stand to close to it to appreciate it in its all embracing stature. Here is a picture of it, with the Group of Eight just arriving at the right spot.

Approaching Double O Arch, Arches      Courtesy Lars Ljungberg    

You say that I am in the picture, laboring after my hiking companions? You are perfectly right! I did this hike TWICE, once within the Group of Eight, but without camera, and once alone with the camera. Lars Ljungberg from the group was so kind as to lend me one of his pictures from the first hike, which I find marvelous.

Now to the somewhat embarrassing part of the story. It is difficult to see on the picture, but underneath the lower "O" of the Arch is a vertical ledge, almost two meters high, which you have to climb in order to pass over to the Arch's other side; only there will you enjoy its magnificent fullness.

I did not bother to climb that ledge on the first hike; what is the use of a magnificent vista, if you cannot catch it on film? But I forgot my limitations as climber! On the second hike, when I went alone, I simply could not find ways and means of climbing that damn ledge. It proved simply too much for me! I waited under it for at least half an hour, hoping for a strong youngster to come along and give me a shove. But nobody came! At long last, I was forced to admit defeat and take the long hike back. To show you what I have missed, National Park Services have come to rescue. They have a huge stock of pictures from their parks on Internet, all of them excellent, and I am really grateful to be able to show this one:

Double O Arch, Arches          Courtesy National Park Services

What else is there to tell from this exhilarating hike? Well, there were many nice views again on the way back, especially since it was getting on in the afternoon and "light was getting right" for a true photographer. But let's make a long story short and just illustrate this with a last picture from Devil's Garden. We are back on the broad and well prepared path that started at Landscape Arch and will soon arrive back at the Trail Head.

Devil's Garden, Arches. Path back to Trailhead

You can imagine that I was a bit tired when I regained the rented car at the Parking Lot. Still, this did not prevent me from stopping the car many a time on the trip back through the Park. The sun was slanting towards the horizon at a leisurely rate, permitting me to take in many more vistas of this marvelous plateau, created by salt. So let's end this post not with words, but with pictures, saying "Goodbye!", through them, to a place of sheer beauty that I won't see again in my lifetime!

Cotton Wood on Courthouse Wash in late afternoon, Arches

The Organ, Arches

The Courthouse Towers, Arches