Deformation monitoring of a structural discontinuity in the seismically active Baikal region

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Currently, one can take for granted the fact that sources of seismic events are always linked to fault zones,
and the larger the fault, the greater the intensity of an earthquake that can be associated with it. This explains
high scientific interest to faults concerning both fundamental problems of seismology, and the need to predict
and, potentially, prevent catastrophic consequences of large earthquakes. Thus, collection of information on
the deformation regime of active faults in the areas with high seismicity is an important problem. In 2009 we
organized a long-term deformation monitoring of one of the fractures in the zone of influence of the Slyudyanka
fragment of the Main Sayan Fault, in a seismically active region. Measurements were carried out in the tunnel
of "Talaya"seismic station , which is located in Irkutsk region, 5 km away from the Lake of Baikal. Presence
of the seismic station allows to trace time correlations of high gradients of strain rate with remote seismic
events. Experiments on artificial action on the fracture were also carried out: explosions of small charges were
applied in a quasi-static way - by hydraulic jacks. As a result it was demonstrated that stressed discontinuity
can response to both dynamic and quasi-static disturbances. An important fact should be emphasized: even
small relative dynamic movements of fracture sides produced by low-amplitude disturbances can initiate residual
deformation. It is expected that further continuous monitoring and analysis of the fracture response to remote
earthquakes will permit to reveal interesting regularities of fault side movement, which may be useful in solving
many problems including earthquake prediction.