Microseismic sounding along the profile in the Ossetian sector of the Greater Caucasus revealed two domains with characteristic properties and morphology deep beneath the mountain system. One...

The paper considers a dispersive geological medium (seismically turbid medium, as defined by A.V. Nikolaev), which is in a stress–strain state. Results of studies on the joint monitoring of seismic effects and radon emanation in various geological environments are presented. It is concluded that the turbidity of the medium, as a statistical characteristic, can be generalized in terms of other media parameters, such as permeability. A stable connection between radon emanation and dynamic processes occurring in a geological environment and caused by external influences has been established. The concentration of radon can also reflect the degree of enrichment of the environment by underground fractures. Consequently, saturation of the environment with radon provides information about the presence of disturbances in a geological environment in the form of cracks and a stress–strain state of the medium before and after seismic loadings. Radon observations make it possible to assess a continuity of the environment and the possibility of leaching in natural conditions. Therefore, it could be efficiently used for underground leaching efficiency assessment.

The paper presents new data on seismotectonic studies along the Adygei profile in the western part of the Central Caucasus and provides an overview of deep geophysical studies of the Greater Caucasus. For the first time, comprehensive geophysical characteristics of a crustal section of the Greater Caucasus across an orogenic structure (along the Adygei profile) have been obtained with a uniform step of observations. Based on factual data obtained by such methods as converted waves from distant earthquakes, magnetotelluric sounding, and gravimagnetic surveys, sinking of the marginal part of the southern microplate into the mantle is verified. It is noted that the contemporary Alpine structure of the Greater Caucasus formed during gentle thrusting of the Earth’s crust (Scythian Plate) from the north on the consolidated crust of the southern microplate.

This publication is concerned with results from area gravity and aeromagnetic surveys (scales 1: 200000 to 1: 50000) over the Central Caucasus, as well as considering surveys along regional measurement lines using earthquake converted waves and magnetotelluric techniques. The results include local anomalies of physical fields for Elbrus Volcano, which are used to infer the locations of a magma source and a magma chamber. No indications that Mt. Kazbek is a living volcano have been found in the physical fields.

The process of the Kolka rock and ice avalanche on September 20, 2002 in the Karmadon Gorge, North Ossetia is reconstructed based on analyzing the instrumental seismic records. The results of calculating the velocities of the rock-ice mass movement on the interval from the Maili Glacier to the Karmadon Gate agree with the results of mathematical modeling the avalanche flow in a gorge. The macroseismic effect of the surge impact on the rocks in the region of the Karmadon Gate is investigated from seismic data and the results of surveying the territory carried out by the authors in 2003–2004.