Skip to main content

Listen to the Cosmic Sound of Sandstone Arches in Bears Ears

A scientist’s mission to record the humming arches of Utah’s national monuments

Certain sandstone arches in Utah emit a steady hum. The Trump administration's attempt to gut Bears Ears and Grand Staircase could stymie geologists who want to study the phenomenon.

Certain sandstone arches in Utah emit a steady hum. The Trump administration's attempt to gut Bears Ears and Grand Staircase could stymie geologists who want to study the phenomenon.

Ron Adcock/Getty Images

The sound is like a low, steady rumble, soothing yet powerful. Imperceptible to the human ear, the red rock arches in Bears Ears and Grand Staircase National Monuments carry with them the deep patterns of the earth’s plates sparked by events like ocean currents colliding in the open Pacific that pump the ocean floor. On the surface, wind spilling over the arches amplifies the vibrations, giving voice to movements in the earth that began thousands of miles away.

Scientists like Jeff Moore have only recently discovered the arches’ hum. We are one year into the legal battle to defend Bears Ears and Grand Staircase, and while we fight in the courts, life and discovery continue in these special places. Now, more than ever, the arches need our voices to protect them.

Headphones may be needed to hear the lowest tones in this recording of Sunset Arch.
Courtesy of University of Utah geohazards research group

Moore, a professor at the University of Utah, has always been fascinated by what makes rocks break and move. That’s how he describes his particular niche in geology, geohazards.

“The earth is teeming with these sorts of mysteries, and it’s my job to uncover them,” says Moore.

Hardy sandstone gives Utah its famous rock formations. Its layers can split open like an accordion and gently erode over millennia into shapes nearly impossible in earthquake country. Moore began to log the swelling and contracting of Utah’s arches as temperatures rose and fell during the day. He wanted to understand their stresses, and know how long their spans will extend out over open air before inevitably collapsing.

“Most people are in awe of these geological wonders, but they don’t recognize how fragile they are,” says Moore. “They think rock is strong. But if you lay your hand on an arch, you get a sense that it is just hanging on. You can see the cracks… and you quickly realize how tenuous the structure is.”

Soon, Moore got to wondering if the ear would be better than the eye at measuring the arches’ movements. He spent hours recording the vibrations of the rocks with seismometers the size of camping thermoses. In the lab, he sped up his recordings to make them audible to humans.

Jeff Moore stands beneath Sunset Arch.
Jeff Moore stands beneath Sunset Arch.
Courtesy of University of Utah geohazards research group

“It sounded like nothing I’d heard before,” says Moore, adding that the arches’ hum is dependent on factors like their size. “Some of the smaller arches have a higher tone, and are a little squeaky.”

In several arch recordings, a mysterious tapping appears on the soundtrack. Asked about the sound, Moore laughed. “It’s probably my team walking as we backed away from our equipment. It’s humans scurrying from the perspective of the arch.”

In late 2017, President Trump threatened to silence the arches’ hum after shrinking Bears Ears and Grand Staircase-Escalante National Monuments by roughly 2 million acres. Mining companies started eyeing monument lands. Earthjustice went to court.

Learn about the dinosaur discoveries that scientists are unearthing in Grand Staircase.
Learn about the dinosaur discoveries that scientists are unearthing in Grand Staircase.
Corey Richards / National Geographic

Within those evicted 2 million acres are ancient cliff dwellings and living ceremonial sites sacred to more than five Native American Tribes fighting for these lands. It’s places like Valley of the Gods, where no one can travel without getting a crick in their neck staring up at red rock spires. It’s dinosaur fossil beds in the Kaiparowitz Plateau of Grand Staircase, where scientists discover new species almost every year. It’s the steep habitat for Utah’s only native herds of cliff-happy bighorn sheep.

It’s also 115 unique arches stripped of their national monument protections.

Arch hunting in the monuments

Jeff got to work with his research team planning expeditions in the monuments for the summer of 2018. Aamon Hatch, a local high school science teacher on break, joined him. They pored over arch hunting websites where amateur geology enthusiasts share their discoveries by dropping coordinates.

“I began to call them ‘the abandoned arches of Bears Ears and Grand Staircase,’” says Moore. “Grand Staircase’s arches had been protected for the last 20 years. Bears Ears’ arches were newly protected. Now they’re left high and dry.”

Determined to document as many abandoned arches as they could, the team ventured into the gutted national monuments. It was like no place Moore had been before. The Henry Mountains in Grand Staircase were the last mountains to be mapped in the lower 48. The Escalante River, which feeds into the Colorado, was one of the last rivers to be mapped. In Navajo, the range is called Dził Bizhiʼ Ádiní or “mountain whose name is missing.”

Moore worries about the impact of human development near these lands — like mine blasting, or the heavy truck traffic new mining roads would bring. The arches evolved in southern Utah partly because the land experiences little seismic activity.

“I worry about them in the way you worry about something you love,” he says.

This model shows how Sunset Arch vibrates.
This model shows how Sunset Arch vibrates.
Courtesy of University of Utah geohazards research group

He isn’t wrong to worry. The Trump administration is rushing through new plans that could open roughly 700,000 acres of Grand Staircase to mining and drilling. It’s a cynical strategy to speed along plans for industrial exploitation that’s often worked against public lands. Earthjustice attorney Heidi McIntosh is fighting to hit the brakes on those plans in court.

While Trump’s executive branch is trying to outrace the courts, Earthjustice will also be defending our monuments lawsuits against the Justice Department’s motion to dismiss them this month. (The weighty question of whether President Trump had the authority to dismantle Bears Ears and Grand Staircase under the Antiquities Act may well be decided, at least preliminarily, at this point.)

Moore’s team ultimately found 37 arches in Grand Staircase and 78 in Bears Ears in the territory stripped out of the monuments. Though their initial project is done, Moore suspects there are many more arches in these wild lands.

“When you stand out there today, you have the feeling ‘this is where the road ends,’” he says. “In between you and the mountain there are no roads. You can feel the vastness.”

Many thanks to the University of Utah’s geohazards team for sharing their research with us.

Overruling Trump: 117 lawsuits filed against the Trump administration.

About the Earthjustice Blog

The views and opinions expressed in this blog do not necessarily represent the opinion or position of Earthjustice or its board, clients, or funders.