Wednesday, May 6, 2009

"...Full of Wonder"

From the Visitor Center at Arches NP, the park road begins a long but well-graded climb up the cliffs to the northeast. A pullout on the right after 1.1 miles gives a good view of Moab Canyon and its geology. The rock layers on this side of the canyon have slipped down more than 2,600 feet in relation to the other side.

Movement took place about six million years ago along the Moab Fault (photo above), which follows the canyon floor. Rock layers at the top of the far cliffs are nearly the same age as those at the bottom on this side. If you could stack the rocks of this side on top of rocks on the other side, you’d have a complete stratigraphic column of the Moab area—more than 150 million years’ worth.

The Park lies atop an underground salt bed resulting from the evaporation of a sea which covered much of the West millions of years ago.

Salt, under pressure, is unstable. As the salt layer shifted, buckled, and liquefied under pressure of the much heavier rock above.

Faults deep in the Earth made the surface even more unstable, as evidenced by the Moab Fault's 2,600 feet displacement (photo 1 above). Fault-caused vertical cracks grew as a result of erosion. The process of water repeatedly freezing and thawing chipped off bits and pieces of rock which the wind then carried away.

Continuing for millions of years, the process of erosion produced the formations in the Park.

In addition to searching for named and unnamed arches, we found many other interesting scenes on the way to these destinations.

While the photos have concentrated on arches and rock formations, there are also canyons and large areas of desert.

This was the scene looking down from the Delicate Arch Viewpoint after a half-mile climb.

Delicate Arch is one of Utah's most famous icons and it is perhaps the world's most famous arch. You see images of it everywhere: on magazine covers, computer screen savers and license plates. Edward Abbey, noted naturalist and author, wrote this: "There are several ways of looking at Delicate Arch. Depending on your preconceptions you may see the eroded remnants of a sandstone fin, a giant engagement ring cemented in rock, a bow-legged pair of petrified cowboy chaps, a triumphal arch for a procession of angels, an illogical freak, a happening.... If Delicate Arch has any significance it lies, I will venture, in the power of the odd and unexpected to startle the senses and surprise the mind out of their ruts of habit, to compel us into a reawakened awareness of the wonderful-that which is full of wonder."

(After reading this quote of Abbey's, I wished I had taken the 1.5-mile hike, described as "difficult" and "...just before you get to Delicate Arch, the trail goes along a rock ledge for about 200 yards," instead of merely seeing the Arch from the distant viewpoint.)

As we left Arches today, this view from Panorama Point showed the desert and the Entrada rock formations with the 12,000-foot La Sal Mountains in the background.

Three days in Arches is just not enough.

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