Utah's arches continue to whisper their secrets

[Judi Lynn]

Seismic studies assess the stresses and health of iconic rock structures
Date:
June 11, 2020
Source:
University of Utah
Summary:
Two new studies show what can be learned from a short seismic checkup of natural rock arches and how erosion sculpts some arches -- like the iconic Delicate Arch -- into shapes that lend added strength.


Two new studies from University of Utah researchers show what can be learned from a short seismic checkup of natural rock arches and how erosion sculpts some arches -- like the iconic Delicate Arch -- into shapes that lend added strength.

A study published in Geophysical Research Letters begins with thorough measurements of vibrations at an arch in Utah, and applies those measurements to glean insights from 17 other arches with minimal scientific equipment required.

The second study, published in Geomorphology, compares the strength of arch shapes, specifically beam-like shapes versus inverted catenary shapes (like Delicate Arch or Rainbow Bridge).

A seismological stethoscope

The Geohazards Research Group at the University of Utah measures small vibrations in rock structures, which come from earthquakes, wind and other sources both natural and human-made, to construct 3-D models of how the structures resonate.

Part of the reason for these measurements is to assess the structural health of the rock feature. In studying 17 natural arches, doctoral candidates Paul Geimer, Riley Finnegan and their colleagues set seismometers on the arches for a few hours to a few days. The data from those measurements, coupled with the 3-D models, gave important information about the modes, or major movement directions, of the arches as well as the frequencies for those modes of vibration.

More:
https://www.sciencedaily.com/releases/2020/06/200611143052.htm