Seismicity caused by hydrological regime of large reservoirs

Abstract

By the analysis of the results of assessing the deformations of the base with a change in the hydrological regime of reservoirs, it is stated that during the operation of large reservoirs, its base and coastal slopes are located in the field of compression and tension loads of the corresponding intensity of the base bending amplitudes with a variation in water volume. It is shown that mountain massifs deformations at large reservoirs' bases can correspond to limiting tectonic focal deformations, which directly affect the regular stress-strain state and background geodynamic movements near the lying seismically active layer of the earth's crust. The study aims to identify the conditions for developing local geodynamic processes in the zones of deformational influence of large reservoirs, solving problems of mathematical physics for specific seismically active fault zones crossing the foundations of large hydraulic structures. An analysis of the results of processing the observed earthquake frequency, elastic displacements in the near zones of reservoirs, and estimates of local deformations shows the influence of changes in the hydrological regime in reservoirs on the activation of weak local earthquakes. It is explained that they are non-linear in nature and are associated with other influencing factors: additional load, the presence of local and active tectonic faults, flooding, and changes in pore pressure.