Insights into water level response to seismic waves: A 24 year high-fidelity record of global seismicity at Devils Hole

Abstract

We studied the 24 year record of water level responses in Devils Hole, Death Valley National Park, NV, to dynamic crustal stresses from earthquakes. The continuous water level record exhibited 219 responses from earthquakes around the world, displaying hydroseismogram and coseismic offset types of response. We found that the water level in Devils Hole is extremely sensitive to earthquakes, and the seismic energy density required to initiate both hydroseismogram and coseismic offset responses is e ~ 10-6 J/m 3, 2 orders of magnitude smaller than previously documented. Multiple mechanisms at Devils Hole may be responsible for observed water level responses to distant earthquakes. The hydroseismogram-type responses are best explained by poroelastic deformation, while coseismic offset responses are likely the result of localized permeability changes. This study could have implication to studying dynamic triggering of earthquakes, as remote earthquakes can lead to pore pressure changes and consequently effective stress changes in fluid-filled fault zones. Key Points Devils Hole sets new threshold of water level sensitivity to remote earthquakes Water level response frequency is characteristic of Rayleigh wave triggering Several mechanisms, both dilatation and permeability change, operate at one site ©2013. American Geophysical Union. All Rights Reserved.