Rock glaciers, such as the Timpanogos glacier in Utah, look like rubble but hold significant amounts of ice beneath their rocky surface. Because they are buried under debris, their internal structure has been hard to assess with traditional methods.
A newly described gravity-based technique offers a workaround. By measuring tiny variations in gravitational pull, scientists can effectively map the hidden glacier without digging or drilling. This allows them to see where ice is concentrated and estimate the total volume of water locked inside.
The approach could make it easier to study other rock glaciers around the world. These formations are increasingly recognized as important water reservoirs, especially in arid mountain regions where seasonal snowmelt is unpredictable.