Journal
GEOPHYSICAL RESEARCH LETTERS
Volume 43, Issue 13, Pages 6852-6860Publisher
AMER GEOPHYSICAL UNION
DOI: 10.1002/2016GL069053
Keywords
high-velocity friction; dynamic weakening; flash heating; superplastic deformation; powder lubrication; nanoparticles
Categories
Funding
- State Key Laboratory of Earthquake Dynamics [LED2014A06]
- National Natural Science Foundation of China [41404143]
- European Research Council starting grant SEISMIC [335915]
- Netherlands Organization for Scientific Research (NWO) through a VIDI grant [854.12.011]
- Department of Terrestrial Magnetism at the Carnegie Institution for Science (Washington, DC, USA)
Ask authors/readers for more resources
To examine whether faults can be lubricated by preexisting and newly formed nanoparticles, we perform high-velocity friction experiments on periclase (MgO) nanoparticles and on bare surfaces of Carrara marble cylinders/slices, respectively. Variable temperature conditions were simulated by using host blocks of different thermal conductivities. When temperature rises are relatively low, we observe high friction in nano-MgO tests and unexpected slip strengthening following initial weakening in marble slice tests, suggesting that the dominant weakening mechanisms are of thermal origin. Solely the rolling of nanoparticles without significant temperature rise is insufficient to cause dynamic fault weakening. For nano-MgO experiments, comprehensive investigations suggest that flash heating is the most likely weakening mechanism. In marble experiments, flash heating controls the unique evolutions of friction, and the competition between bulk temperature rise and wear-induced changes of asperity contact numbers seems to strongly affect the efficiency of flash heating.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available