Slow-slip events in semi-brittle serpentinite fault zones
- Creators
- Goswami, A.
- Barbot, S.
Abstract
Slow-slip events are earthquake-like events only with much lower slip rates. While peak coseismic velocities can reach tens of meters per second, slow-slip is on the order of 10^(−7±2) m/s and may last for days to weeks. Under the rate-and-state model of fault friction, slow-slip is produced only when the asperity size is commensurate with the critical nucleation size, a function of frictional properties. However, it is unlikely that all subduction zones embody the same frictional properties. In addition to friction, plastic flow of antigorite-rich serpentinite may significantly influence the dynamics of fault slip near the mantle wedge corner. Here, we show that the range of frictional parameters that generate slow slip is widened in the presence of a serpentinized layer along the subduction plate interface. We observe increased stability and damping of fast ruptures in a semi-brittle fault zone governed by both brittle and viscoelastic constitutive response. The rate of viscous serpentinite flow, governed by dislocation creep, is enhanced by high ambient temperatures. When effective viscosity is taken to be dynamic, long-term slow slip events spontaneously emerge. Integration of rheology, thermal effects, and other microphysical processes with rate-and-state friction may yield further insight into the phenomenology of slow slip.
Additional Information
© The Author(s) 2018. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. Received 02 November 2017; Accepted 11 January 2018; Published 18 April 2018. We thank Chris Marone and an anonymous reviewer for their valuable comments. This research was supported by the National Research Foundation of Singapore under the NRF Fellowship scheme (National Research Fellow Awards No. NRF-NRFF2013-04) and by the Earth Observatory of Singapore, the National Research Foundation, and the Singapore Ministry of Education under the Research Centres of Excellence initiative. A. Goswami acknowledges the financial support received from the Caltech Summer Undergraduate Research Fellowship (SURF) program. A. Goswami is the 2017 Kiyo and Eiko Tomiyasu SURF Scholar, and received funding jointly from the California Institute of Technology and Nanyang Technological University. This work comprises Earth Observatory of Singapore contribution no. 173. Author Contributions: A.G. conducted the stability analysis and the numerical modeling. S.B. designed the study and prepared the figures. All authors wrote and reviewed the manuscript text. The authors declare no competing interests. Data availability: The datasets generated during and/or analysed during the current study are available from the corresponding author on reasonable request.Attached Files
Published - s41598-018-24637-z.pdf
Supplemental Material - 41598_2018_24637_MOESM1_ESM.pdf
Files
Name | Size | Download all |
---|---|---|
md5:3eaa3a88a3bf54a141f02c4047f9bdb5
|
123.4 kB | Preview Download |
md5:cae1bb26e00664e00c0f6e935f720a6d
|
1.7 MB | Preview Download |
Additional details
- PMCID
- PMC5906616
- Eprint ID
- 89089
- Resolver ID
- CaltechAUTHORS:20180823-131609206
- NRF-NRFF2013-04
- National Research Foundation (Singapore)
- Earth Observatory of Singapore
- Ministry of Education (Singapore)
- Caltech Summer Undergraduate Research Fellowship (SURF)
- Nanyang Technological University
- Created
-
2018-08-23Created from EPrint's datestamp field
- Updated
-
2022-03-11Created from EPrint's last_modified field