Essence: Boulder Benchmark is located north of the Burr Trail, west of Deer Creek, and east of the town of Boulder, Utah. Revel in relaxed slickrock hiking while climbing Peak 6,507', the high point on a piñon-juniper topped mesa. Resting on swaths of Navajo Sandstone are rounded boulder volcanics. The wide-spread abundance of "boulder balls" is just one compelling feature in this geological wonderland. The hike is within the Grand Staircase-Escalante National Monument.
Travel: Measure distance from the junction of Utah 12 and the Burr Trail in the town of Boulder. Drive east on the paved Burr Trail, entering GSENM. Most of the hike is visible from the road. At 5.2 miles, pull into a large gravel parking lot and primitive camping area on the right. If you are driving along the Burr Trail from the east, watch for a magnificent ponderosa in the center of the pullout, 1.1 miles west of Deer Creek.
Distance and Elevation Gain: 8 miles; 1,800 feet of climbing
Total Time: 5:00 to 6:30
Difficulty: Off-trail; navigation moderate; Class 2; no exposure
Maps: King Bench; Steep Creek Bench, Utah 7.5' USGS Quads
Date Hiked: October 29, 2020
Quote: Are these the end times? Yes. And they have been this way since the beginning. Welcome to planet Earth, a wonderful but not entirely stable place to live. Craig Childs
Catastrophic flows during the Ice Age dislodged black basalt boulders from the High Plateau of Boulder Mountain and stranded them throughout the region. They adorn the surface of the Navajo Sandstone composing Boulder Benchmark, image-center. Deer Creek, the red corridor on the right, begins from an incision on the steep southern slopes of the 70 square mile Boulder Mountain summit. (Thomas Holt Ward, photo)
Route: Cross the Burr Trail and head north up onto a large mesa, topping out on Peak 6,507'. Descend north to the saddle south of Boulder Benchmark being careful to skirt private property. This land is delineated on the map to the right of my track in a light color. Bear northeast, heading two ravines, and mount the south slope of the benchmark. Continue northwest to a better viewpoint on a low prominence if you wish. On the return, you may flank Peak 6,507' on the east.
From the parking lot, elevation 5,820 feet, look north and locate two sandstone knobs. We climbed the craggy knob left of image-center for fun but you may skip it and head directly up the prominence on the south rim of the first mesa, image-right. Regardless, cross the Burr Trail and walk up a minor wash. It is sandy at first but very soon transitions to bedrock.
You will get a flavor for this mellow, pleasant hike immediately while weaving through boulder balls strewn about. Notice the mustard-colored liesegang banding embedded in the sandstone, here and throughout the area.
Standing on the initial knob at 6,300 feet, 0.8 mile, look back on the Burr Trail, the angular dome east of the parking lot, and Durffey Mesa west of Deer Creek. (THW, photo)
My knowledge of geology is rudimentary but even so, I was struck by the varied geological phenomena seen on this short trek. The fundamental rock is Navajo Sandstone. In characteristic shades of white, it is prominent throughout Southern Utah and the Colorado Plateau. It was once the largest sand desert in the history of the Earth. The formation is 2,200 feet thick in places. It forms rounded domes, sheer cliffs, and slickrock sheets.
Scattered about on the surface are irregular-shaped concretions. These features form early in the burial history of the sediment. They are formed by the precipitation of mineral cement which makes them more resistant to weathering than the sedimentary host stratum. The iron-colored ripples and bubbles throw off sheens of light.
Also lying on the surface is an abundance of chalcedony, a microcrystalline form of silica created during volcanic activity. Some of the stones are translucent (agate) and others opaque (chert). Presumably, they were brought down from Boulder Mountain along with the basalt boulders. We happened upon lithic scatters of worked chalcedony. Please leave the lithic feed stocks and archaeological treasures where you find them.
Barge through an astonishing number of naturally distributed boulders that are strikingly out of place. They vary tremendously in size from spheres you'll dislodge with your step to boulders rivaling your height. Bluebell Knob (elevation 11,317 feet) is the crest of Boulder Mountain located on the Aquarius Plateau, the tallest of the High Plateaus of Utah. The rounded basalt and andesite boulders originated in 20 million-year-old lava flows that mantle Boulder Mountain. The freight of boulders was hurled down from the mountain by floods and debris flows at a time when the Ice Age glaciers were melting. As you climb to the knob at the south end of the first mesa, the boulder balls are on the verge of becoming an obstacle.
Walk due north across the flat mesa top. The mature piñon-juniper woodland is complimented by ephedra, sagebrush, snakeweed, and buffaloberry. The ground is spongy, showing no sign of a social trail or even footprints. Nondescript Peak 6507', 1.9 miles, is at the far north end of the mesa. From here, you'll have a visual of Boulder Benchmark, the sandstone butte west of Deer Creek, shown below. Take stock of your intended route before launching so you do not infringe on private property which includes the saddle and land to the east. We dropped west of the ridgeline as we approached the saddle.
From the highpoint, descend through a boulder field onto the slickrock. Singular concretions embellish the broad expanse of smooth white stone.
We happened on the southwest property corner near the saddle.
Walk through a sage flat as you pass west of the saddle at 6,140 feet, 2.5 miles. Boulder Benchmark is image-right.
Our final approach to the crest was optimal on a shallow inclined plane, avoiding steep slopes elsewhere.
Two ravines flow southwest on the southern slope of the mountain. Head them both on the east.
A solitary hoodoo stands on the north rim of the second and larger ravine.
Sandstone is weathering out from under a balancing boulder. (THW, photo)
As we topped out on the butte, we had to hunt around for the Peak 6,642' benchmark. It is located near the southeast corner, 3.4 miles. The tiny piece, the size of a quarter, is on an inconspicuous boulder low to the ground.
Consider walking to the north end of the butte and continuing on to the yellowish dome pictured below. It's just another 0.4 mile and is an excellent viewpoint. You'll have to turn around here because it is very near the Monument boundary.
Pass over sandstone painted crimson by the iron-bearing mineral hematite.
Pick your way through another community of boulder balls. (THW, photo)
Seen from the globular sandstone knob, nearby in the west are irrigated fields on the outskirts of the town of Boulder. (THW, photo)
East, is the main channel of Deer Creek, Peak 6,597', and the Henry Mountains. Visible in this image is Mount Ellen in the north block.
It appears that Nature got a little carried away dispensing peppercorns on the western slopes of Boulder Benchmark. (THW, photo)
Return to the benchmark. Pictured below is the south slope, the private land east of our route, and the north and east slopes of Peak 6,507'. You may either return over the top of the mesa (the easier choice) or flank it on the east.
We wanted to see more terrain so we diverged from our incoming route at elevation 6,340 feet and headed southeast, shown.
We bypassed a wall by walking east for a short distance. We returned to the proper trajectory on a lower bench, shown. The terrace dwindles and footing is uneven on the rubbly, slanted slope.
Keep heading southwest and you will cross a low ridge at 7.3 miles, 6,000 feet. From there you will see the familiar dome signifying the location of the parking lot.
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