The Mecca Wilderness area was established in 1994 when the U.S. Congress set over 26,000 acres in the Mecca Hills to be managed by the U.S. Bureau of Land Management (BLM). This incredible area is located only 35 miles from Palm Desert and just south of Joshua Tree National Park. Without a doubt, Mecca is our favorite hiking destination in Southern California. It's a magical location and every visit provides a unique experience.
Fortunately, effort are underway to further protect these incredible lands. Representative Raul Ruiz is formally proposing a new national monument in Southern California. The Chuckwalla National Monument would span about 660,000 acres including the Mecca Wilderness area. The site would stretch between Joshua Tree National Park's southern boundary to the Colorado River, near the Arizona border. A map outlining the proposed national monument with the Mecca Wilderness Area outlined in black.
Today's moderately strenuous hike was to a group of slot canyons in the northeast quadrant of the hills. I didn't zoom in on the trail intentionally. This view shows how the hills are confined to a relatively small area between the flats and the Orocopia Mountains on the right.
Hike Distance: 8.6 miles
Elevation Gain: 1,001 ft
TrailsNH Hiking Difficulty Calculator: 131 (Moderately Strenuous)
Click here to navigate to the TrailsNH website for an description of the hiking difficulty.
The Mecca Hills, situated on the northeast side of the Coachella Valley, came into being as a result of the ongoing collision between the North American Plate and the Pacific Plate along the San Andreas Fault network. These geologic layers of sediment were deposited on a relatively flat surface and have since been converted to sedimentary rock that has been uplifted and turned by the push and pull of the San Andreas Fault to the west, and the Eagle Canyon, Painted Canyon, Hidden Springs, and Grotto Faults that slice through this landscape. This movement caused the structurally weak sedimentary rocks to collapse into tightly compressed near-vertical folds.
Like all hikes in Mecca, the trail started in a sandy wash.
Less than a mile into the hike, the canyon walls began to rise. These walls are composed of sediments that accumulated over a 3 to 4 million years period.
The sediments originated from uplift and erosion of the Little San Bernardino and Orocopia mountains and runoff from the ancestral flow of the Colorado River. As each layer of sediments was laid down, the underlying sediments were compacted and cemented into the sedimentary rock that we see today.
The canyon walls tell the story of chaotic debris flows of sand, gravel, cobble and boulders that were carried by fast moving runoff. As the water velocity decreased, rubble began to settle out with the largest objects settling first until all that remained in the slow moving water was sand and silt. Each of these 'boulder rock layers' in the sidewall tells the a story of a chaotic debris flow.
But why are the Mecca Hills dissected by all of these narrow steep-walled canyons? The answer is a combination of erosion and uplift. Erosion brought the sediments but changes 2.5-3 million years ago along the San Andreas Fault network caused extensive uplift in the Mecca Hills. Major uplift began again about 700,000 years ago. With these periods of uplift, the water that deposited sediment also began eroding the weakest rock layers and carving out these canyons.
Unlike the Grand Canyon eroding over millions of years by the continuous flow of the Colorado River, these canyons were formed by flash floods that sliced through the sediment. Raging flows dislodged large cobble and boulders which hammered the canyon walls and floor dislodging even more sediment and swiftly deepening the canyon.
This hike wasn't all about geology, we were lucky in March to see wildflowers dotting the landscape.
This flowering salt cedar or tamarisk tree looks beautiful but it provides no value to the desert ecosystem. Most importantly, they outcompete native vegetation and use vast amount of water. In addition, they are adept at extracting salts from the water and soil which are concentrated in their needle-like leaves. When the leaves fall to the ground, they render the soil sterile for other plants. Lastly, tamarisk provide little, if any, food or shelter for native mammals, birds, reptiles and insects. They may look beautiful but as an invasive plant, they need to be removed!
As we walked further into the canyon, the walls began to close in. Despite the destructive power of flash floods, the canyon has characteristically smooth and curved walls. The canyon started out with a wide opening becoming more narrow the further we hiked.
The narrowing arises due to differential erosion, that is erosion that occurs at different rates based on the hardness and resistance of the surface materials. In this case, weakness in the sedimentary rocks on the canyon floor causes 'down cutting' and slot formation.
Geologists have discovered that small flood events may cause more erosion than large floods. It’s not so much the size of the flood, but the size of the particles, cobbles and boulders that get carried along with the water that cause the most erosion and deepen the slot.
We had sufficient lighting from above to take this selfie.
Although the slot was not exceedingly 'tight', the near vertical walls were within arms reach.
Rock slides have created interesting choke points along the trail.
A ladder help get us to the upper level of this 'open air' cave like formation.
Shortly afterwards,we exited the closure and it was then that we realized the size and scale of the rock slide that had created the 'cave'.
A few minutes later we ran into our next obstacle.
Fortunately, we didn't need to crawl on our stomach to continue on the trail.
After telling Dave it was probably safe, he proceeded into the dark opening.
After a short distance, color variations in the rocks caused by different levels of sunlight alerted us that we were approaching the end.
Time to exit this slot and begin the trek back to the trailhead.
Soon we were back in the main canyon wash.
Sometimes it's easy for me to lose sight of the grand scale of these land features but then I see the canyon walls towering above Dave and I'm instantly reminded of why this place is so special.
Ocotillos along the trail look like thin-spiked fence poles. This tall, deciduous shrub can reach heights up to 20-feet and is estimated to live up to 60 years. Their spiny stems are leafless most of the time, but after a good soaking rain plants will be covered with clusters of narrow oval leaves about 2 inches long. The leaves remain on the plant until the soil dries out and then they fall off. Ocotillo can grow and lose leaves four or five times in a year depending on rainfall.
On closer inspection, many of the branches were topped with dense clusters of red tubular flowers. These flowers help explain the shrub's name, ocotillo means 'little torch' in Spanish. Blooming season occurs between mid-February to mid-April. Because ocotillo are drought tolerant, they bloom consistently every year and provide a dependable food source for hummingbirds even when other spring plants are unable to bloom.
On the way back to the trailhead we decided to explore a random opening in the canyon wall.
The opening became more narrow the further we went.
A 10-foot dry fall soon greeted us but Dave quickly scaled it.
A slightly higher dry fall soon followed. I took the lead so that I could capture photos as Dave climbed.
It was easily climbable, as long as you didn't let the height get to you.
Up and over the top.
From this height, we had incredible views of the greater than 4200-ft thick 3-4 million years continuous succession of sedimentary rocks that are exposed in the Mecca Hills
I stayed on top to get this 'look down' view as Dave returned to the wash.
We noticed this chuckwalla lizard sunning itself on a rock pile. From the coloration, I think this was a male chuckwalla. When sunning, these lizards will flatten their body against the rock to absorb more heat. This low-profile also affords greater camouflage and predators will have trouble detecting either a chuckwalla or its shadow. Visible in the photo are the loose folds of skin around the shoulders, neck and torso which come in handy. When threatened, this flat-bodied lizard scurries into a crevice, gulps air to inflate its body, and wedges itself into the safety of the rocks, making it extremely difficult for a predator to remove it.
Rock debris fields are a common hiking obstacle in the Mecca Hills.
Walking through the wash, we had great views of the different layers in the sedimentary rock strata. In general, the colors are determined by the environment where they are deposited. Red rocks form where oxygen is present and darker sediments form when the environment is oxygen poor.
There is no better photo to end the blog with than with these near vertical sedimentary rock folds caused by the movement along the faults that snake through the Mecca Wilderness.
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