During my travels in Southwest US, I often came across these funny vertical stripes on the walls. Looked as if someone had poured down varnish from the walltop.
Later on, I learned that this indeed is called "desert varnish".
I checked the web, and found the following infos:
(for more details please check NPS.gov website, the Canyonlands' one):
Desert varnish only appears where water flows over rocks, and bacteria are present. It is composed of fine-grained clay minerals, which contain black manganese oxide and red iron oxide, or hydroxides.
The third picture shows a path of dried water, which obviously contained much of salt and manganese minerals - the greenish-whitish color shows it.
Now directly from NPS/Canyonlands Website:
Desert varnish consists of clays and other particles cemented to rock surfaces by manganese emplaced and oxidized by bacteria living there. It is produced by the physiological activities of microorganisms which are able to take manganese out of the environment, then oxidize and emplace it onto rock surfaces. These microorganisms live on most rock surfaces and may be able to use both organic and inorganic nutrition sources. These manganese-oxidizing microorganisms thrive in deserts and appear to fill an environmental niche unfit for faster growing organisms which feed only on organic materials.
The sources for desert varnish components come from outside the rock, most likely from atmospheric dust and surface runoff. Streaks of black varnish often occur where water cascades over cliffs. No major varnish characteristics are caused by wind.
Thousands of years are required to form a complete coat of manganese-rich desert varnish so it is rarely found on easily eroded surfaces. A change to more acidic conditions (such as acid rain) can erode rock varnish. In addition, lichens are involved in the chemical erosion of rock varnish.
Delicate Arch is exciting - but make sure, you'll look around as well. Just behind the wall, that separates the amphiteatre and Delicate Arch from the trail, there is a steep canyon with fantastic rock formations (i.e. northeast of Delicate Arch).
For getting an idea on this canyon - check the Terraserver view: Canyon off Delicate Arch: the one at "1-2 o'clock" that throws a shadow.
Not many tourists take this hike out to Broken Arch. In fact, we hadn't considered it until it was recommended at the Moab Information Center. It turned out to be an excellent recommendation!
This hike is 2 miles return trip and should only take an hour. The trailhead is located in the Devil's Garden campground, across from campsite #40.
The arch is not actually broken but has what appears to be a crack in the center of it, you can see the crack in my photo. We are assured that there is no imminent danger of the arch falling and the path will take you right through the arch to the other side. There are great views up here as well.
If you have extra money, I highly recommend renting a jeep for a day. This will enable you to go on roads that people aren't even allowed to hike on! It can be pricey, so you may consider a guided jeep adventure. A little cheaper....and you still get to see the "backcountry". There are many places in Moab that offer rentals and tours. Prices are all about the same. It just depends on what you want to do. Moab visitor center has brochures!!
Arches National Park is a big draw...and understandably...it is so unique and so beautiful. But, do crowds usually take away from the beauty ofplaces for you? Then get your 4 wheel drive vehicle, and get off the asphalt pathway of the park.
Just north of the Sand Dunes Arch on the road through the park, there is a turnoff onto a gravel/sand road. This is Salt Valley Road, and it will take you down into the Salt Valley, and west across the park. About 7 miles after turning onto Salt valley Road, there is a second turn off on the left, which takes you back to the Klondike Bluffs, and to Tower Arch.
The road then turns to the south, across sand and stone, a rather interesting trail. This trail will take you south through the valley, past Eye of Whale Arch and down to Willow Flats Road, which will take you west out of the park to Highway 191.
The park specifies that the trail may be impassable when wet. Due to really deep soft sand in some areas, I could see many stock 4 wheel drive vehicles getting stuck in those conditions. Once on Willow Flats Road, though, you'll be OK with just about any 4 wheel drive vehicle. See my tips about dinosaur tracks that you pass while on Willow Flats Road.
The trails can get lonely, and see minimal traffic. Just keep that in mind if you plan to venture out here. We actually went to these trails for two days, once with our group of friends, the next day just us in RedRover. It was romantic being out in the valley, alone, at sunset...
Canyonlands National Park's Islands In the Sky is located 30 miles from the town of Moab. Here you will find overlooks allowing you to view huge vistas that range from the rivers flowing through canyon bottoms to the heights of distant mountaintops. These beautiful views stretch across canyon after canyon to the horizon a 100 miles in distance. Like Arches National Park you will find a variety of hiking trails to walk. Your guides for these hikes will be rock cairns marking your route. You may also choose to take the drive, which offers a number of beautiful look of points. For information about the park you may write to Superintendent, Canyonlands National Park, 2282 S.W. Resource Blvd., Moab, UT 84532.
Tower Arch is located in the northwestern section of Arches National Park, amongst a block of rock called the Klondike Bluffs. There are two ways to get there...take Salt Valley Road to a trail turnoff for the arch. Then, a short 4 wheel drive trail, requiring high clearance 4 wheel drive vehicles, can get you within 1/4 mile of the arch, or an easy dirt road to a hiking trailhead. The hike is over a mile of strenous trail.
If you hadn't guessed, we drove as far back as we could. The road got a little harder, not to difficult for our truck, but stock 4 wheelers may experience body or suspension damage. Be careful. The trail back to the arch from this parking area was only about 1/4 mile, but was quite strenuous.
I got underneath the arch, which I would estimate was about 20 foot in width and fifty feet high. Ruins of a fallen arch nearby add to the fragility of the area.
I encountered a rather tired hiker that took the other way back at the arch, other than that, not a soul to bother us.
This difficult to get to arch in Arches National Park, has an odd name, and unique beauty. The trailhead to this remote arch is on a sandy road require high clearance 4 wheel drive vehicles. Road may be impassable when wet.
Take Salt Valley Road and turn left on sandy road. Due to very deep sandy hills, travel is suggested to be north to south.
Due not go alone if you wish to attempt this route. And bring plenty of water. The remoteness is truly beautiful, but can be treacherous
This photo shows the view as we have just hiked past the tall rock spire pictured in the previous tip along the hike to Broken Arch. I found it fascinating to be hiking amongst these interesting rock formations. For those of you interested in geology, I have found an explanation for these natural wonders...
"The park floats on a salt bed, which once liquefied under the pressure exerted by the rock above it. About 300 million years ago, this salt layer bulged upward, cracking the sandstone above. Over time the cracks eroded, leaving long fins of rock." It is these "fins" that have since eroded further to form all of the arches for which the park is famous.
The hike to Broken Arch is more about the walk than the destination though you can continue on to Sand Dune Arch which saves campers at Devil's Garden from having to use their cars. This flat walk through grasslands does have some fun through the arch maneuvers and it's a great way to escape the crowds. Only those in the park for more than two days will consider this walk. Access if from Sand Dune Arch or from the Devil's Garden Campground.
Morning Glory Arch or Natural Bridge is surprisingly one of the longest arches in the world. It ranks 7th longest span on the website I looked at and that is no small feat. At 243 feet (74 m) it should probably be well known. You have not heard of it though because it is fairly hard to get to and because it is an alcove arch, which makes it somewhat less impressive.
When hiking to the arch through Negro Bill Canyon it seems like the trail will never end, but after 3 miles (4.8 km) you find the arch it only has a gap of about 15 feet (4.5 m) from the cliff behind it which makes it pretty hard to photograph, especially in low light. There is also a small stream if you can call it that which runs seemingly out of the wall and into a small pond 75 feet (22m) beneath the arch.
Directions: From Moab, follow 128 to the Negro Bill Canyon and the trail to morning glory arch is about 3 miles (4.8 km).
Klondike Bluff is one of the only places in Arches National Park where there is a chance of not seeing another person. The area can be seen on the left as you drive down the main road approaching Devils Garden area. Access to Klondike Bluff is a dirt road just before you approach Skyline Arch. The trail head has been updated and now has a pit toilet. The start of the trail is a bit steep but once on top the trail levels off and is very enjoyable. The trail can be difficult to find at times because the cairns are very small. Half way on the hike there is four pincles on your left called the Marching Men. After this you will drop into a dry wash and up a deep, sandy hill. Once on top, loop around and you will be at Tower Arch.
If you go up into Tower Arch it is possible to go left and work your way up and out of the canyon, passing through a narrow slot. Once on top it is possible to circle around back to the Marching Men, however there is no trail and this should not be attempted unless you are very familiar with route finding skills.
Driving out of Arches National Park on Willow Springs Road, we happened across this sign, highlighting the spectacular dinosaur tracks preserved in this area.
During the Jurassic Period, some 165 million years ago, the Moab area was part of a shallow tidal lands of an inland lake. The area's vegetation attracted many dinosaurs, and in turn, predators, including the two types whose tracks can be seen very well here: the Saurapod and the Therapod. Both were human-sized dinosaurs that walked upright.
Their tracks were preserved in the mud as it slowly turn to sandstone under the pressures of time. The Saurapod tracks were broader, with shorter toes, whereas the Therapod tracks showed more of a "claw-like" print, with longer toes and narrower heel.
There are over 2,000 tracks spread throughout the Salt Valley wash.
To reach the tracks, travel on Route 191 north of Moab and turn right onto Willow Springs Road until you see the sign, or head into Arches National Park, and turn onto Willow Flats Road from the area by Balanced Rock. The tracks can be found just west of the Park's boundaries, just feet from the designated road.
Located just 19 miles from Arches national park, Dead Horse Point provides a spectacular overlook of the Colorado River making a complete 180 degree turn around a rock fin. this park is fairly small but with a view like this it makes it well worth while.
Located in Moab, UT this National Forest has mountains aspen, pine, firs, spruce and rugged plateaus with great scenery of red rocks.Part of the Forest is located in Colorado.
Open Year round- and camping is permitted May through October. Located approximately 5 miles southeast of Arches NP.