Utah's mountain ranges may be hiding as much as 1 billion metric tons of ice within rock glaciers, according to research from the University of Utah. Scientists discovered the massive, hidden water stores through a study of the Timpanogos Rock Glacier, which was conducted following field campaigns in the fall of 2024.
Hidden Ice in Timpanogos
Researchers from the University of Utah have identified that the Timpanogos Rock Glacier, located under the summit of Mount Timpanogos near Salt Lake City and Provo, contains enough frozen water to fill 600 Olympic-sized swimming pools. The volume of ice within the glacier is estimated at 1.5 million cubic meters, a quantity equivalent to the volume of the largest pyramid at Giza in Egypt, according to Bronson Cvijanovich, a former graduate student in the Department of Geology & Geophysics.
Unlike conventional glaciers, rock glaciers are composed of thick layers of loose rock and rubble that obscure large masses of ice. The Timpanogos Rock Glacier is particularly ice-rich, consisting of 83% ice and 17% loose rock, Cvijanovich said. This composition makes the glacier a potentially climate-resilient water storage site, as the thick rock carapace protects the ice from melting, Cvijanovich noted.
Mapping Through Gravity
To map the interior of the glacier, the research team utilized a novel technique involving minute differences in gravitational pull between rock and ice. This method allowed scientists to create a 3D image of the buried ice body, functioning similarly to how a CT scanner images bone and tissue within the human body.
Geophysics professor Michael Thorne explained that there is a large contrast in mass density between the rock that forms Mount Timpanogos and the much lower density ice in the adjacent rock glacier. As measurements are taken over areas with thicker ice, researchers observe a larger decrease in gravitational acceleration.
After collecting gravity readings at 232 different spots in a grid atop the glacier during the fall of 2024, the team had to correct the data for the position of the sun and moon, elevation, latitude, and terrain. The researchers then applied Bayesian statistics to perform the 3D imaging, a process that required months of computation time, Thorne said.
The Formation of Rock Glaciers
The research revealed that these rock glaciers are not merely remnants of the Ice Age, which peaked between 21,000 and 18,000 years ago. Instead, they are water stores that formed over thousands of years after the original Ice Age glaciers melted away.
While some rock glaciers may have melted out, the Timpanogos Rock Glacier is still actively adding ice, according to glaciology professor Leif Anderson. The researchers developed a mathematical model showing that rock glaciers gain mass when rockfalls from steep-walled valleys or cirques bury persistent snow in the upper parts of the glacier.
Global and Local Water Scales
The study of the Timpanogos Rock Glacier provides a scale for estimating the total ice volume in rock glaciers globally. Based on the relationship between a rock glacier's surface area and its internal ice volume, researchers estimate that the world's 50,000 known rock glaciers hold approximately 48 gigatons of water, or 1 billion metric tons.
For the state of Utah, researchers estimate that the 836 documented rock glaciers may hold 1 gigaton, or 815,000 acre-feet of water. This makes these features critical from a water resource standpoint, especially in an arid state like Utah, Cvijanovich said.
Research Publication Details
The findings were released through two separate studies. One study, titled "The internal ice content of Timpanogos Rock Glacier, Utah, USA from 3-D Bayesian inversion of gravity data," was published on August 26, 2026, in the Journal of Geophysical Research. The second study, titled "Mass Addition to Timpanogos Rock Glacier: Debris-Covered Snow and the Importance of Interannual Variability in Headwall Erosion and Climate," was published on April 2, 2026, in Geophysical Research Letters.
The research was supported by the U.S. Geological Survey, the National Science Foundation, the University of Utah’s Wilkes Center for Climate Science & Policy, the University of Utah’s Office of Undergraduate Research, and the Summer Program for Undergraduate Research.
