The mechanics of the ice cover of Lake Baikal has been studied through monitoring of its deformation and seismic effects and full-size uniaxial compression and shear tests in 2005–2007. We measured the shear strength of ice specimens and large in situ blocks (σ = 0.2−1.9 MPa) and investigated it as a function of air temperature and ice structure. Deformation was analyzed in terms of various natural controls, such as air temperature and pressure, wind, sub-ice currents, and local earthquakes. Precise strain measurements along ice cracks were used to explore the strain behavior of ice, including the cases of dynamic failure (ice shocks). Measurements by seismic station Baikal-12 were used to monitor diurnal background microseismicity variations and to record an ice quake with its magnitude (M = 0.3–0.8; E = 104–105 J) comparable to a medium-size rock burst or a small earthquake. Ice quakes were studied in terms of their nucleation, dynamics, and aftereffects, as well as the strain and seismic responses of the ice, using sub-ice explosions in the latter case. The natural conditions of deformation in the elastoviscoplastic Baikal ice are similar to lithospheric processes and thus can be employed in tectonophysical modeling with scientific and practical implications for hazard mitigation.

The paper presents the main results of comparison between the records of four nearby earthquakes made on the ice cover of Lake Baikal and on the hard rock ground (seismic station located in Listvyanka set tlement). Since the discovered differences between the records may be due to several factors-sedimentary cover, water medium, ice cover, interfaces between media, and microseisms-the experimental investigation and understanding the main regularities of seismic waves conversion will require the creation of a database of earthquakes recorded on the ice cover of the lake and statistical analysis of record processing results.

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series of full-scale experiments was performed to study the influence of impact loads on the parameters of seismic vibrations initiated in variable friction. The study was conducted on a test setup Tribo which is a movable concrete slab modeling an allochthon on a rough plane of the Angara fault segment in Baikal region. Contact interactions of asperities in the slip zone were recorded using strain and load measuring equipment and four seismic stations Baykal-7HR widely used for recording earthquakes. The proposed physical modeling method and obtained results can be of interest for the development of new physical models of differently scaled sources of seismic energy dissipation in tectonic faults and can be useful for seismological studies, related data interpretation, and improvement of extended forecast of rock bursts and earthquakes.