Utah's iconic Rainbow Bridge hums with natural and man-made vibrations,according to a original University of Utah study, published September 21 in Geophysical Research Letters. The study characterizes the different ways the bridge vibrates and what frequencies and energy sources cause the rock structure to resonate. The vibrations are small, and according to geology and geophysics professor Jeff Moore,but the study provides a baseline measure of the bridge's structural integrity and shows how human activities can rattle solid rock.
Source: phys.org