Probing the Damage Zone at Parkfield
- Author(s)
- Andrew Delorey, Robert A. Guyer, Götz Bokelmann, Paul A. Johnson
- Abstract
Rocks are heterogeneous materials that exhibit nonlinear elastic (anelastic) behavior at scales ranging from the laboratory to Earth. In the laboratory, typical, complex relationships exist between stress and strain that include hysteresis, finite relaxation times, strain rate, and history dependence. These behaviors are linked to important characteristics such as stress, porosity, permeability, material integrity, and material failure. We adopted a "pump-probe" type experiment common in laboratory studies, using solid earth tides as the low-frequency pump and empirical Green's function as the high-frequency probe. By probing the velocity at different points in the pump cycle, we constrained important information about the strain-modulus relationship. Near the San Andreas Fault, we observed strongly nonlinear elastic behavior that characterizes the damage zone. We also constrained important aspects of hysteretic behavior that are related to damage properties and possibly pore pressure. Away from the fault, the nonlinear behavior is diminished.
- Organisation(s)
- Department of Meteorology and Geophysics
- External organisation(s)
- University of Vienna, Los Alamos National Laboratory
- Journal
- Geophysical Research Letters
- Volume
- 48
- No. of pages
- 9
- ISSN
- 0094-8276
- DOI
- https://doi.org/10.1029/2021GL093518
- Publication date
- 07-2021
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 105122 Seismic
- Keywords
- ASJC Scopus subject areas
- Geophysics, General Earth and Planetary Sciences
- Portal url
- https://ucrisportal.univie.ac.at/en/publications/a6a53788-3b71-4ef7-8162-e5a02b83a9a1