Measuring the tempo of Utah's red rock towers
You won’t see them move no matter how closely you watch.
You won’t hear their vibrations, even with your ear pressed to the cool sandstone.
But new research shows that the red rock towers found in Southern Utah and throughout the Colorado Plateau are in constant motion, vibrating with their own signature rhythms as unique as their dramatic profiles against the depth of the blue desert sky.
University of Utah researchers know well how rock towers and arches shimmy, twist and sway in response to far-off earthquakes, wind and even ocean waves. Their latest research compiles a first-of-its-kind dataset to show that the dynamic properties, i.e. the frequencies at which the rocks vibrate and the ways they deform during that vibration, can be largely predicted using the same mathematics that describe how beams in built structures resonate.
Knowing these properties is crucial to understanding the seismic stability of a rock tower and its susceptibility to hazardous vibrations. But it’s tough to get the needed data, partly because getting to the base of the towers often requires traveling through treacherous terrain — and then someone has to climb them to place a seismometer at the top.
With the help of experienced climbers, though, University of Utah researchers have now measured the dynamic properties of 14 rock towers and fins in Utah, creating a unique dataset with a variety of heights and tower shapes. More