Rozel Point, Great Salt Lake, Box Elder County, Utah.
Photographer: Ken Krahulec

The 1500-foot-long Spiral Jetty, built in 1970 of black Tertiary-age basalt, is the  principal earthwork of the  prominent American sculptor Robert Smithson.

San Rafael Swell, Sevier County
Photographer: Robert F. Biek

Alluvial and wind-blown sediment partly conceals the Jurassic-age Entrada Sandstone in the Last Chance Desert, which occupies the axis of the Last Chance anticline. The narrow, jagged, black ridge at the center of the photo is a basaltic dike of probable late Tertiary age (3 to 5 million years old) that intrudes the Entrada Sandstone.

Bryce Canyon National Park, Garfield County, Utah
Photographer: William Lund

The Pink Cliffs (Eocene-age Claron Formation) form the uppermost step of southwestern Utah’s spectacular Grand Staircase.

Arches National Park, Grand County
Photographer: William Lund

Delicate Arch is formed of Jurassic-age sandstone—the Slick Rock Member of the Entrada Sandstone (base and pedestals) and Moab Member of the Curtis Formation (bridge). With a horizontal span of 32 feet and a vertical span of 46 feet, Delicate Arch is small compared to many other natural arches, but its free-standing nature makes it unique in the world and emblematic of Utah’s spectacular red-rock geology.

Big Cottonwood Canyon, Wasatch Range, Salt Lake County
Photographer: Liz Paton

On the east slope of Mt. Millicent (10,452 feet), Lake Mary occupies part of a basin carved by Ice Age glaciers. The surrounding peaks are composed of granitic rock of the Tertiary-age Alta stock.





Head of Sinbad, San Rafael Swell, Emery County
Photographer: J. Buck Ehler

Dutchman Arch guards the path to Devil’s Racetrack, a popular recreation trail in the San Rafael Swell. Named after a local Dutch cattleman, the arch is composed of the Jurassic-age Wingate Sandstone deposited in ancient sand dunes.

Little Cottonwood Canyon, Wasatch Range, Salt Lake County
Photographer: Valerie V. Davis

Viewed across Albion Basin from the Secret Lake trail, the southfacing slopes of the Flagstaff Mountain area reveal tilted Cambrian- to Pennsylvanian- age strata. The deformation of these rocks attests to the severe folding, faulting, and tilting undergone by this mountain range.



Garfield County
Photographer: Michael Vanden Berg

Windows form within the Tertiary-age Claron Formation as wind and water erode the brightly colored sandstone and siltstone into fins and hoodoos at Bryce Canyon National Park. Thor’s Hammer, the official icon of the Utah Geological Survey, is visible in the lower-right corner.

Sixty years of Utah Geology will leave you with A LOT of photos, so we are going to share them with you. Introducing the UGS Photo Of The Day, or POTD for short. Enjoy!


San Juan County

Photographer: Michael Vanden Berg

Wilson Arch is probably the most accessible natural arch in southern Utah. It is perched on a cliff of the Jurassic-age Slick Rock Member of the Entrada Sandstone next to Highway 191 half way between Moab and Monticello. North of Moab, the Entrada Sandstone is host to the vast majority of the arches in Arches National Park.