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Areas of Research

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The first results of field experiments with the impact on the geomedium of electrical impulses generated during the start-up of geophysical magnetohydrodynamic (MHD) generators were obtained at the Garm (Tajikistan, Pamir) and Bishkek (Kyrgyzstan, Northern Tien Shan) test sites at the end of the 20th century. In the works of Tarasov N.T. It was established that there is a trigger effect of electromagnetic fields on local seismicity, which manifested itself in a short-term increase in seismic events of low classes after sounding. In later works, the previously discovered effect was confirmed - variations in seismicity were observed during deep sounding of the earth's crust with unipolar current pulses produced by an electrical exploration generator set ERGU-600-2. Despite the fact that the presence of the influence of electromagnetic fields on seismic processes is beyond doubt, the question of the physical mechanisms responsible for this effect is still controversial. Considering this circumstance and the fact that carrying out field tests encounters significant difficulties, both technical and economic, a significant contribution to understanding the mechanism of converting the energy of electromagnetic fields into the energy of elastic waves from emerging discontinuities can be made by laboratory modeling on rock samples.

The similarity of processes occurring in complex geological structures of the earth's crust and deformation processes observed in laboratory experiments on loaded rock samples creates a prerequisite for studying the processes occurring in the depths of the earth's crust by carrying out physical modeling on rock samples. To reveal the characteristic features of the influence of an external electric field on loaded samples of heterogeneous materials, the NS RAS carried out experiments on various rock samples.

The design of the experiments was determined by the problem of developing models describing the influence of electromagnetic (EM) fields on the process of destruction of earth's crust materials during the preparation of earthquakes

The laboratory experiments carried out at the RS of RAS were also motivated by the need to study the triggering effects of electrical impulses in experiments on the samples of those rocks that occur in the field of electromagnetic sounding (traditionally called the Bishkek geodynamic testing ground, BGG). It should be noted that for a series of samples of granite, gabbro, marble, etc., made from rocks of the same deposits, a better reproducibility of the loading characteristic (σ – ε - characteristics) is achieved under uniaxial compression in comparison with model materials (cement- sand mixtures). Such reproducibility under the same loading conditions is important for revealing the reaction of the medium to additional influences (including electrical impulses) against the background of the usual behavior of the AE activity and deformation parameters.

Thus, the main task to be solved in the ESMS laboratory is to study the influence of external influences of an endogenous and exogenous nature on the process of destruction of the environment at various scale levels, and to develop and refine models of the trigger effect:

  • identification of the effects of synchronization of external influences and changes in physical parameters at various scale levels.
  • measurements of seismic noise and geoacoustic emission (large-scale level of micro- and “nano-earthquakes” with sources ranging in size from several meters to several tens of meters (magnitude M <0)).
  • laboratory modeling on samples of geomaterials (centimeter sizes of samples - the scale of microcracking).
 

Photogallery

Geographic location

40 km. from Bishkek