Lost Wages, Nevada

Las Vegas is known for it's dirty thrills and free eye candy on the strip. Few people realize that the same can be said for the hills and deserts surrounding Sin City. This place simply is underrated as a mountain bike destination - especially in January when shorts, t-shirts, and fingerless gloves are considered proper attire. We lived in Vegas for 3 years, and I was continually surprised at how much good and varied biking there is. We jump at every excuse to go back for a visit. Last week it was a "business trip."
Above: view toward Las Vegas from the top of the Dead Horse Loop.

It was tough deciding between the 3 popular Vegas riding areas - they all have their pros, but with only one day to ride, I had to go with Cottonwood Canyon. Some 60-plus miles of singletrack weave their way through some stunning scenery in and around the Red Rock Canyon National Conservation Area. This is a classic desert ride with Joshua Tree forests, wild burros, abandoned mines and there are even parts of the trail that follow the exact horse-hoof-beaten path of the the Old Spanish Trail.

Above: a lightning-sparked fire at the foot of Mount Potisi has really darkened an already sun-charred desert.

Above: evening shadows begin to stretch away from massive cliffs of Aztec Sandstone.



Here are a few photos from rides-past at the other Las Vegas fat-tire hot spots.

Above: Bootleg Canyon is extremely dissimilar to Cottonwood in terms of riding conditions and scenery.

Why such a difference even though both are within a few miles of the city? Geology, of course. At Cottonwood you're riding mostly on unconsolidated alluvial fan deposits lending to a rolling, relatively smooth ride with an occasional outcrop of ledgy Permian-age limestone to keep things interesting.

The trails at Bootleg on the other hand, traverse the deeply incised guts of ancient volcanoes. There is nothing smooth about Bootleg trails - 90% of the time you are riding right on very sharp, chaotic, and unforgiving outcrops of volcanic rock. Riding here will greatly improve your technical skills in a hurry. In the photo above, you can see a black mountain of lava on the left, and red lava rock on the right. These lavas were sourced from two different calderas or large volcanoes.
When Vegas has an extra wet January and February, Bootleg is the place to be in early Spring. The normally drab mountain comes to life with colorful knee-high flora. Oh, and desert sheep are all over out here.


Last, but not least, are the Cowboy Trails. Very challenging riding up on a raised block of Permian Limestone with stiff climbs and white-knuckle descents with plenty of drops.
Above: the sandstone crags of Red Rock Canyon captures your attention on the way to the top.

Below: view toward a smoggy Las Vegas from the top of the Cowboy Trails.
So, what's it like cruising through the Sonoran Desert, riding single-handed on a narrow trail, dodging spear-like yucca? Click below to get an idea.

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Cedar Canyon Rock Fall

On January 5th, a quiet and peaceful evening up Cedar Canyon was suddenly and violently halted.

Only a low gurgling noise from the nearly-frozen Coal Creek could be heard until several hundreds of tons of rock detached from the canyon's high rim and crashed across the hillside, pummeling trees and leaving large craters and gouges. Car-sized boulders twirled and bounced toward the river. The impact of the falling rock pulverized some of the material into a thick dust cloud that settled over this entire section of the canyon.

There were some pretty lucky people in the canyon that night. First, there was the snow-plow driver who drove through the canyon unscathed at 7:30. Then there were the motorists who slowed down when thick dust made the curvy road hard to follow, and were finally stopped when their headlights revealed the freshly-deposited mountain of rock blocking their path. After trying to make sense of the mess that laid before them, they turned around and called authorities from a nearby canyon restaurant at about 8:15.

A very small earthquake was recorded by the The University of Utah Seismograph Stations at 8:04. Seismologists at the U say the waveform of the event in consistent with an impact at the surface rather than a deeply sourced earthquake on a fault. You know you're dealing with a pretty serious rock fall when it is large enough to be recorded by seismographs.

Back to the people who first called it in at 8:15 - it is about a 10 minute drive from the rock fall to the restaurant, putting the motorists within a couple of minutes of being buried in this catastrophic event!


Above: looking up at the rock fall source area. The thick ledges of sandstone belong to the Tibbet Canyon Member of the Cretaceous Straight Cliffs Formation. This is normally a fairly competent unit, however, the Tropic Shale and Dakota Formation that form the slope below are extremely weak units that not only erode easily, but they are also prone to landslides. Both landslides and comparatively small rock falls have plagued this portion of the highway for years, but this is the first rock fall of this size. The crushed concrete barrier at the bottom of the photo was constructed to catch rock falls, but it certainly wasn't designed to stop anything this big.
Above: all 6 feet of me taking a closer look at one of the larger boulders that almost made it to the river.
After I climbed down along the boulders, I decided to cross the river and get a closer look from across the canyon. Looking back at my tracks, I noticed how much dust this thing produced and deposited on the opposite side of the canyon.
Above: the bulldozer here was no match for this moderate-sized boulder. UDOT anticipated having to blast several of the largest boulders, taking up to two weeks to clear and patch the road. They must have worked overtime, because they had the road open about 6 days later.

As part of the natural canyon-widening process, landslides and rock falls will continue to be an intermittent headache for UDOT in this part of the canyon. Lets just hope folks traveling through this canyon continue to have good luck.

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Desert Dreamin'

I know, I know, it's winter and I should be playing in the snow, but the desert was calling.

I had heard about the Gold Butte Backcountry Byway from my days living in Las Vegas. Details were sketchy and incomplete. All I could surmise was to expect a long dusty road out on the east side of Lake Mead linking a few odd and interesting things together, with miles and miles of good old Mojave-Desert emptiness in between. Sounded like the perfect place to explore by bike...
After a 5 AM start and a 2 hour drive, I arrived at Whitney Pocket - one of several colorful isolated masses of upturned Navajo, err... I mean Aztec (since I was in Nevada) Sandstone. A closer look into the deep cracks and canyons of Whitney Pocket reveals some fine work by the CCC boys of the 1930s. This cleverly designed reservoir captures water and delivers it to a nearby stock tank - still works like a charm some 70 years later.

Above: a shady and cool food storage cave next to the historic CCC camp.
Blazing 8 miles or so down the Gold Butte Road brought me to the head-scratching geologic phenomenon known as Devil's Throat. This is one impressive sinkhole (that's still growing), but the puzzling thing is that sinkholes typically form in wet areas with lots of limestone bedrock. But here we are in the middle of the desert and no bedrock at all - just a seemingly infinite column of alluvial fan material being swallowed into a deep unseen cavern.
Looking over the edge of Devil's Throat.

Heading west from Devil's Throat, the rough Jeep road devolves into a faint path in a wash bottom. I soon encountered more red Aztec Sandstone with a nice desert varnish - a perfect medium to depict that sheep hunt, the location of a cool spring, an alien encounter, or whatever.

After slogging several miles through the wash, I came upon one of the most unique places I've ever been to. I guess it's similar to Goblin Valley but the portly goblins, rounded toadstools, and bulbous mushrooms of Goblin Valley contrast greatly to the razor-edged dragons, piles of shattered glass, and knife-wielding warriors of this place, known to some as "Little Finland."

Above: looking out the yawning mouth of a sleeping giant.
This area would be the perfect laboratory for a geologist interested in differential erosion and the formation of tafoni (weather pitting) features.
So what geologic processes have contributed to the formation of these erosional monsters? The answer is a normal fault. In the photo above you can see the pale orange Jurassic-age Aztec Sandstone on the left has been dropped down adjacent to a dark-red Triassic-age mudstone on the right. Normally, the down-dropped (or hanging wall) side of the fault sits topographically lower than the upthrown (or footwall) side of the fault. But here, the very strong and resistant Aztec Sandstone in the hanging wall sits much higher because the weak mudstone of the footwall has eroded away faster than movement on the fault can bring it up. So in short, this fault has created an elevated block of Aztec Sandstone and the edge of that block is eroding into some pretty amazing features.
Above: looking north along the fault-edge block of eroding Aztec Sandstone.

Below: looking south along the fault. Faults often impede the lateral movement of groundwater, forcing water to the surface and creating springs. Here in the desert that spring water evaporates as soon as it reaches the surface, leaving behind the white minerals (mostly gypsum, salt, and calcium carbonate) that were in the water's solution. This small amount of water brought to the surface also has created an oasis in an otherwise bone-dry desert, with palm trees and even a couple of small hanging gardens. These springs were undoubtedly a critical resource for Native Americans. This is confirmed by the hundreds of petroglyphs found in the area.

Above: a layer of minerals coat crossbeds of Aztec Sandstone near the fault.
Like a clumsy guy in a fine china shop, a small miss-step and a bump could shatter what 100s of years of erosion have taken to create. These formations are extremely delicate.


Do you remember being a kid and taking your little green plastic army men outside into the dirt and rocks, trying to imagine a full-scale world for them to battle in? Well, this would be the ultimate place for that. There are miniature mars-like landscapes here that would make the most imaginative Hollywood set producers envious.





Taking a closer look and trying really hard not to break anything.
Above: the large block of sandstone on the right has detached from the main cliff face along a joint.



Above: a huge desert palm grows where it can draw water up out of fractured rock within the fault zone.

Above: small crossbed of Aztec Sandstone, amazingly preserved, sticking 4 feet out in relief where the rest of the sandstone has eroded away.
Interesting geology abounds everywhere you look out here. Above appears to be a massive thrust fault, most likely from the Cretaceous-age Sevier Orogeny (mountain building event). The blue and gray Paleozoic carbonate rocks on the left have been smashed up and over the younger red Aztec sandstone on the right.

Above: a classic angular unconformity (gap in geologic time) with contorted maroon Triassic-age shale overlain by much younger alluvial (stream-derived) material.

Below: the Overton Arm of Lake Mead is visible the distance.
The sandstone bluffs northeast of Black Butte and Bitter Ridge are dotted with petroglyphs of various ages and styles. I spent maybe an hour looking, and I'm guessing I just barely scratched the surface.
Above: snake-like petroglyphs line a window that overlooks a sea of petrified sand dunes that glow in the evening sun.

At the end of the day, I had biked about 32 miles, many of them slow-going through soft sand. With a few miles of hiking and rock-scrambling, it all adds up to one very successful desert romp.

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