Rupture Dynamics of a Fault with a Heterogeneous Interface

Rupture Dynamics of a Fault with a Heterogeneous Interface

Ostapchuk A.A., Martynov V.S.

Institute of Geophere Dynamics of Russian Academy of Sciences, 119334, Moscow, Russia.

Development of methods to change sliding regimes of small faults seems a realistic, though a very complicated scientific and engineering task, which demands conducting laboratory, numerical and field experimental investigations. Transformation of a fault sliding regime can be performed, for example, through an anthropogenic change of the frictional properties of the zone of sliding. A change of frictional properties in laboratory experiments [1] was performed by injecting fluid in the area of principal slip zone.

Regularities of propagation of the coseismic rupture along a fault under an external effect were studied in numerical experiments. The fault was a 1D slider model consisting of 25 connected blocks. The friction resistance acting on each block is described by a Rate & State friction law. It is shown that a local change of frictional properties of the fault interface at the final stage of a seismic cycle may be an effective mechanism of decreasing the velocity of rupture propagation and the coseismic energy.

[1] Kocharyan G.G., Ostapchuk A.A., Martynov V.S. (2017). Alteration of fault deformation mode under fluid injection. Journal of Mining Science 53(2), c. 216-223. DOI: 10.1134/S1062739117022043.