Notch Peak, Utah 2015
In June of 2015, I decided to climb Notch Peak in West-Central Utah. Notch Peak (3220 m elevation) is in Utah’s West Desert, west of the town of Delta, Utah. Notch Peak is part of the House Range mountains and Notch Peak Wilderness Study Area.
This relatively easy hike follows Sawtooth Canyon as it meanders though a gorge-like canyon, past sage brush and a mini natural arch. The views at the top can’t be beat.
The hike is located in the very wild and unpopulated west desert of Utah. Services, people, and help are a long ways away when visiting the area.
The hike is quite casual, but the summit offers jaw dropping exposure down the second highest vertical drop in the United States, (the first is El Capitan in Yosemite National Park). Some debate the second highest drop status depending on how you define pure vertical drop, but it is a stunning drop to stand on top of, and a hike I would strongly recommend.
This part of the House Range is chiefly made up of a passive margin sequence of Cambrian to Ordovician carbonate rocks.
The top of the range is the type section for the aptly named Notch Peak Dolomite, (500 million year old Orr & Weeks Formations). At the base of the range is the pink/orange Notch Peak granite and monzonite, which is Jurassic in age (169 million years old). Around Notch Peak, especially from the west side (Tule Valley side), white Lake Bonneville fossiliferous marls occur.
Because of the intrusion, “Painter Spring Canyon below the notch can clearly show a well-developed metamorphic Skarn-aureole and even inter-fingering textures between the intrusion and the limestone. Also, small quantities of tungsten and placer-gold have been found.
The northwest face of the mountain is a massive carbonate rock (limestone and dolomite) cliff with a 670 m of vertical rise, making it among the highest cliff faces in North America. Overall, the summit rises about 1,360 m) above Tule Valley, (pictured below).
Pictured below, west side of the “House Range” as seen from milpost 28 on U.S. 6-50. Upper third of Notch Peak is the section for the cliff-forming Upper Cambrian Notch Peak Formation. The tree-covered slopes at the base of these cliffs expose fossiliferous cliffs of the upper Orr Formation. The Big Horse Limestone Member of the Orr and Weeks Limestone are also shown. White layers of limestone beds that were recrystallized and bleached (marblized) by heat and fluids from the Jurassic granitic intrusion exposed in the knobby ledges left of the straight canyon. This metamorphism took place at a depth of several thousand meters. Unlabeled exposures on the right side of the layering have been offset by faulting. Present exposure of the limestone beds is a result of uplift and erosion during the Cretaceous Sevier Orogeny.
The view of the west desert of Utah, from its summit give some perspective on the lonely western side of the state and how isolated and expansive it is.
The massive limestone and dolomite bedding is nearly flat and horizontal (not folded). Tectonic folding could have resulted in fractures that weaken rock layers. Similarly, tectonic compressional forces have not thrusted these rock layers over one another. [Elsewhere in the Basin and Range past episodes of tectonic folding and thrusting have fractured and weakened otherwise similar formations and thereby reduced their integrity and ability to form towering cliffs]. Though there is no clear evidence for such forces, an east-west oriented fracture (perpendicular to the range-front fault) could have provided a zone of weakness contributing to the north-facing orientation of the peak’s greatest cliff.