Slip acceleration generates seismic tremor like signals in friction experiments

Dimitri Zigone (1) , Christophe Voisin (1) , Éric Larose (2) , Francois Renard (3) , Michel Campillo (2)

1 Cycle sismique et déformations transitoires
2 Ondes et Structures
3 Mécanique des failles

Since their discovery nearly a decade ago, the origin of seismic tremor remains unclear. Recent studies indicate that various driving phenomena such as Earth and ocean tides, regional and teleseismic earthquakes enhance tremor activity. Observations of the coincidence with slow‐slip events and of fast migrations of tremors have led frictional slip to be consid- ered as the possible source of tremors. Indeed, laboratory fric- tion experiments succeeded in generating and recording tremor like signals (TLS). Here we show a systematic corre- lation between the onset of slip acceleration and the emission of TLS in a laboratory friction experiment. TLS are generated when the shear stress reaches the peak static resistance and the dilatancy meets its maximum that is when the mature inter- face is close to failure. This robust result provides a compre- hensive image of how natural seismic tremors might be generated and/or triggered by passing seismic waves, tides or even slow slip events.

Mots clés: friction; acoustic emission; tremors

Domaines: Géophysique [physics.geo-ph]; Géophysique [physics.geo-ph]; Milieux et Changements globaux

Dimitri Zigone, Christophe Voisin, Éric Larose, Francois Renard, Michel Campillo. Slip acceleration generates seismic tremor like signals in friction experiments. Geophysical Research Letters, 2011, 38, pp.L01315. ⟨10.1029/2010GL045603⟩. ⟨hal-00556704⟩