skip to main content

DOE PAGESDOE PAGES

Title: Dynamically triggered slip leading to sustained fault gouge weakening under laboratory shear conditions

We investigate dynamic wave-triggered slip under laboratory shear conditions. The experiment is composed of a three-block system containing two gouge layers composed of glass beads and held in place by a fixed load in a biaxial configuration. When the system is sheared under steady state conditions at a normal load of 4 MPa, we find that shear failure may be instantaneously triggered by a dynamic wave, corresponding to material weakening and softening if the system is in a critical shear stress state (near failure). Following triggering, the gouge material remains in a perturbed state over multiple slip cycles as evidenced by the recovery of the material strength, shear modulus, and slip recurrence time. This work suggests that faults must be critically stressed to trigger under dynamic conditions and that the recovery process following a dynamically triggered event differs from the recovery following a spontaneous event.
Authors:
ORCiD logo [1]
  1. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Publication Date:
Report Number(s):
LA-UR-15-29118
Journal ID: ISSN 0094-8276
Grant/Contract Number:
AC52-06NA25396; EE0006762; EAR 1520760; 656676
Type:
Accepted Manuscript
Journal Name:
Geophysical Research Letters
Additional Journal Information:
Journal Volume: 43; Journal Issue: 4; Journal ID: ISSN 0094-8276
Publisher:
American Geophysical Union
Research Org:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org:
USDOE
Country of Publication:
United States
Language:
English
Subject:
58 GEOSCIENCES; Earth Sciences; earthquake triggering, critical stress state
OSTI Identifier:
1374315
Alternate Identifier(s):
OSTI ID: 1402231

Johnson, Paul Allan. Dynamically triggered slip leading to sustained fault gouge weakening under laboratory shear conditions. United States: N. p., Web. doi:10.1002/2015GL067056.
Johnson, Paul Allan. Dynamically triggered slip leading to sustained fault gouge weakening under laboratory shear conditions. United States. doi:10.1002/2015GL067056.
Johnson, Paul Allan. 2016. "Dynamically triggered slip leading to sustained fault gouge weakening under laboratory shear conditions". United States. doi:10.1002/2015GL067056. https://www.osti.gov/servlets/purl/1374315.
@article{osti_1374315,
title = {Dynamically triggered slip leading to sustained fault gouge weakening under laboratory shear conditions},
author = {Johnson, Paul Allan},
abstractNote = {We investigate dynamic wave-triggered slip under laboratory shear conditions. The experiment is composed of a three-block system containing two gouge layers composed of glass beads and held in place by a fixed load in a biaxial configuration. When the system is sheared under steady state conditions at a normal load of 4 MPa, we find that shear failure may be instantaneously triggered by a dynamic wave, corresponding to material weakening and softening if the system is in a critical shear stress state (near failure). Following triggering, the gouge material remains in a perturbed state over multiple slip cycles as evidenced by the recovery of the material strength, shear modulus, and slip recurrence time. This work suggests that faults must be critically stressed to trigger under dynamic conditions and that the recovery process following a dynamically triggered event differs from the recovery following a spontaneous event.},
doi = {10.1002/2015GL067056},
journal = {Geophysical Research Letters},
number = 4,
volume = 43,
place = {United States},
year = {2016},
month = {2}
}