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An empirically based steady state friction law and implications for fault stability.

ABSTRACT: Empirically based rate-and-state friction laws (RSFLs) have been proposed to model the dependence of friction forces with slip and time. The relevance of the RSFL for earthquake mechanics is that few constitutive parameters define critical conditions for fault stability (i.e., critical stiffness and frictional fault behavior). However, the RSFLs were determined from experiments conducted at subseismic slip rates (V??0.1?m/s) remains questionable on the basis of the experimental evidence of (1) large dynamic weakening and (2) activation of particular fault lubrication processes at seismic slip rates. Here we propose a modified RSFL (MFL) based on the review of a large published and unpublished data set of rock friction experiments performed with different testing machines. The MFL, valid at steady state conditions from subseismic to seismic slip rates (0.1?µm/s?

SUBMITTER: Spagnuolo E

PROVIDER: S-EPMC5021208 | biostudies-literature | 2016 Apr

REPOSITORIES: biostudies-literature

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An empirically based steady state friction law and implications for fault stability.

Spagnuolo E E Nielsen S S Violay M M Di Toro G G

Geophysical research letters 20160414 7

Empirically based rate-and-state friction laws (RSFLs) have been proposed to model the dependence of friction forces with slip and time. The relevance of the RSFL for earthquake mechanics is that few constitutive parameters define critical conditions for fault stability (i.e., critical stiffness and frictional fault behavior). However, the RSFLs were determined from experiments conducted at subseismic slip rates (<i>V</i> < 1 cm/s), and their extrapolation to earthquake deformation conditions (< ...[more]

PMID: 27667875

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