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Updated: Jun 3, 2026
07:39
The Role of Fabric in Frictional Properties of Phyllosilicate-Rich Tectonic Faults
Published on: November 6, 2021
Fault lubrication during earthquakes
1Dipartimento di Geoscienze, Università di Padova, Padova 35131, Italy. giulio.ditoro@unipd.it
Nature
|March 25, 2011
Summary
Rock friction significantly decreases during seismic slip, a phenomenon termed fault lubrication. This lubrication, driven by physicochemical processes, occurs in various rock types and is crucial for understanding earthquake mechanics.
Area of Science:
- Geophysics
- Earthquake Mechanics
- Rock Physics
Background:
- Fault friction is critical for earthquake mechanics, influencing stress drop and energy release.
- Seismological methods for determining fault friction are challenging, necessitating experimental approaches.
Purpose of the Study:
- To review experimental data on rock friction at seismic slip rates.
- To elucidate the mechanisms and extent of fault lubrication during earthquakes.
Main Methods:
- Analysis of approximately 300 published and unpublished experiments.
- Utilized rotary shear apparatus to simulate seismic slip rates (0.1-2.6 m/s).
Main Results:
- Observed a significant decrease in rock friction (up to one order of magnitude) at seismic slip rates.
- Identified physicochemical processes (e.g., gelification, dehydration, melting) as drivers of fault lubrication.
- Experimental results align with natural fault products and seismological estimates.
Conclusions:
- Faults likely experience lubrication during earthquakes, regardless of rock composition or weakening mechanisms.
- Experimental findings are relevant for understanding earthquake nucleation at depths of 7-15 km.
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