A new concept is proposed concerning the origin and inception of ‘initial’ faults and formation of large blocks as a result of cooling of the Archaean lithosphere, during which Benard cells had formed (Fig. 5). At locations where cooling convection currents went down, partial crystallization took place, stresses were localized, and initial fault occurred there. The systems of such fault developed mainly in two directions and gradually formed an initial block pattern of the lithosphere. This pattern is now represented by the largest Archaean faults acting as boundaries of the lithospheric plates and large intraplate blocks (Fig. 6). This group of faults represents the first scaletime level of destruction of the lithosphere. Large blocks of the first (and may be the second) order, which are located on the viscous foundation, interacted with each other under the influence of the sublithospheric movements or endogenous sources and thus facilitated the occurrence of high stresses inside the blocks. When the limits of strength characteristics of the block medium were exceeded, the intrablock stresses were released and caused formation of fractures/faults and blocks of various ranks (Fig. 14). This large group, including faultblock structures of various ranks and ages, comprises the second level of the scaletime destruction of the lithosphere.

The intense evolution of ensembles of faults and blocks of the second scaletime level is facilitated by shortterm activation of faultblock structures of the lithosphere under the influence of strain waves. Periods of intensive shortterm activation are reliably detected by seismic monitoring over the past fifty years. Investigations of periodical processes specified in the geological records over the post-Proterozoic periods [Khain, Khalilov, 2009] suggest that in so far uninvestigated historical and more ancient times, the top of the lithosphere was subject to wave processes that  influenced the metastable state of the faultblock medium of the lithosphere.

At the second scale-time level, the lithosphere is destructed in accordance with the laws of destruction of elastic and brittle bodies; at all hierarchical levels, the lithospheric destruction complies with the similarity patterns; the lithospheric destruction processes are characterized by fractality and take place synchronously with other destruction processes.

Equations of the fault (7) and block divisibility (8) of the lithosphere and the generalized equation (9) of the faultblock divisibility of lithosphere are proposed.

By the present stage of the geodynamic evolution of the Earth, the horizontally-layered zonal pattern of destruction of the Earth has been established (Fig. 15). The next step would be obtaining the knowledge of the law that governs the evolution of the lithospheric destruction as a whole. The subjects for discussions hold be variations of the rheological properties of the vertical profile of the lithosphere, impacts of the time factor on the rheological and mechanical properties, and, lastly, the initial heterogeneity of the lithospheric medium in combination with modern geodynamic processes. This problem is solvable, and its importance for practical applications is undubitable.

The Yuzhno-Sakhalinsk mud volcano is located in the southern part of the Sakhalin Island within the area of the Central Sakhalin fault, one of the largest disjunctive dislocations of the island. The volcano was monitored during field seasons in the period from 2005 to 2007, and data on flow rates, chemical and isotope compositions of gases, temperature and chemical composition of watermud mixture in the volcano’s blowouts were collected and analysed. During the observation period, seismic activity in the region under study was significantly variable in time and space. The monitoring results revealed «traces» of two earthquakes in the blowout activity of the Yuzhno-Sakhalinsk mud volcano – the Gornazavodsk earthquake, that took place on 17 (18) August 2006, and the Nevelsk earthquake of 2 August 2007. Based on results of our analyses of the field data and mathematical simulation data, it is possible to conclude that an additional inflow of «deep geofluids» could not have been a major trigger of the activity of the volcano after the earthquakes. In our opinion, all the observed anomalies may result from «water – rock – gas» interactions in the top part of the mud volcano’s feeder channel. A combination of water and gas flows in the volcano’s channel and silica-alumina rocks comprises a specific geochemical system that is sensitive to external (seismic) impacts. Therefore, comprehensive consideration of physical and chemical processes within fluid-dynamic systems is required for assurance of correct interpretation of empirical data.

The Prikolyma terrain is a part of the Yana-Kolyma orogenic belt located in the North Eastern Asia. It is generally composed of the Proterozoic deposits, including sandstones, metapellites, quartz-feldspar and carbonate rocks, meta- and hyperbasites. The Prikolyma terrain represents a fragment of passive margin of the North-Asian craton that was detached in the Middle Paleozoic due to progressing rifting. Subsequent geological development of the terrain was determined by accretion events at its boundary with margin of the North-Asian craton and the Omolon microcraton. Its longterm geodynamic evolution is reflected in the character and sequence of formation of the Prikolyma terrain deformation structures. 

In the central part of the Prikolyma terrain, i.e. in the basin of the Malaya Stolbovaya river, two reference areas of tectonics were studied, which contain packs of thrust sheets complicated by subsequent highangle faults.

The fault pattern is complex, and its major elements are gently dipping zones of plastic deformation, which mark the boundaries of petrographically heterogenous plates. The thrust packs  are more than 200 m thick; their root zones are represented by series of highangle reverse faults. Another important element of the fault pattern is highangle zones of brittle deformation, which kinematic characteristics are ambiguous. A vertical component of displacement is predominant for the faults of the north-western strike; a strike-slip component is characteristic of latitudinal and meridional faults. The fault pattern developed in several stages under the impact of fields of tectonic stress, which vectors were variable. The folds, comprising a uniform structural paragenesis with thrusts, are of great importance for the structure under study. The largest folds exhibit the asymmetric structure with the N-E dipping axial planes. Axes of smaller folds are oriented to N-W and N–NW.

Four stages of deformation are distinguished in the history of geological development of the Prikolyma terrain. The earliest stage was characterized by the N-E compression resulting in formation of the N-W-oriented thrusts and folds and zones of greenschiest dynamo-metamorphism. During the second stage, the axis of compression gained the E–NE orientation, and the axis of extension was oriented to the N–NW, which influenced the formation of the submeridional reverse faults and thrusts. During the third stage, the axis of compression was N-W oriented, and the axis of extension gained the N-E orientation. Thereat, the sublatitudinal and submeridional structures were activated as strike-slip faults, the N-W structures as normal faults, and the N-E structures as reverse faults. The above resulted in the formation of structures of volume extension, which are favorable for localization of magmatic bodies and ore streaky-veined structures. At the final stage, compression in the meridional direction lead to the formation of thrusts and reverse faults along the sublatitudinal displacements, normal faults along the submeridional displacements, and strike-slips along the N-E and NW displacements.

The first deformation stage was contemporaneous with the long-term period of compression in the Riphean and Early Paleozoic, when the dynamo-metamorphic complex of the Prikolyma terrain was developed. In the second stage, the Prikolyma terrain was detached from the margin of the North-Asian craton. In the Early Cretaceous, the third stage took place, when rearrangements of the field of tectonic stresses and transition to conditions of general extension caused emplacement of granitoids and quartz veining. The N-W orientation of the compression vector suggests that the third stage was related to the regional tangential compression due to the asymmetrical collision of the Prikolyma terrain and the Omolon microcraton. In the final stage, rotation of the vector of compression, associated with development of numerous N-W and N-E-oriented fractures, reflected the occurrence of the epiorogenic rifting. The above-described stages of formation of the deformation structure of the Prikolyma terrain are evidently correlated with the main tectono-magmatic stages of development of the NE margin of the North-Asian craton, which took place in the Late Paleozoic and the Mesozoic.

The article is aimed at discussion of geological and geophysical aspects of the ‘asthenospheric’ interpretation of the ‘anomalous’ mantle layer that is revealed in the Baikal rift zone by deep seismic sounding (DSS) methods. Based on the analysis of the geoelectrical model, estimations of rheological properties, regional geothermal and deep petrological data, it is concluded that the ‘anomalous’ mantle phenomenon should be interpreted within the framework of solid-phase models. It is shown that the actual minimum depth to the top of the asthenosphere is about 60–70 km in the region under study, and temperatures at the surface of the Earth’s mantle varies from 600 to 900 °С. It is most probable that velocities are reduced in the ‘anomalous’ mantle layer due to the presence of hightemperature spinel-pyroxene facies of the mantle rocks.

It is revealed that high-Mg lavas (MgO=11.0–15.8 wt. %) are spatially controlled by linear zones extending for more than 90 km and demonstrate chemically distinct differences from moderately-Mg compositions (MgO=3.0–11.0 wt. %), which occupy the isometric area of the Dariganga volcanic field. From the major and trace-element data on the rocks in the field under study, we have justified a petrogenetic mode of the uniform one-level mantle magmatism. Our model differs from the contrasting magmatism model of the processes that developed at two levels beneath the Hannuoba volcanic field. Based on tomography images showing the East Mongolian local low-velocity anomaly in the upper mantle, we suggest that magmatism of Type 1 occurred in the mantle sources at the asthenosphere–lithosphere boundary and the underlying asthenosphere as a reflection of a relatively weak mantle flow that may have ascended from a depth of ~250 km. Magmatism of Type 2 occurred in the isolated sources of the sublithospheric mantle and the asthenosphere–lithosphere boundary as an evidence on the initially strong mantle flow that may have ascended from a depth of ~410 km.

The paper presents results of the mathematical synthesis of the method of passive location of a seismic wave source. The method employs measurements of regular attenuation of seismic oscillation amplitudes. If it is impossible to determine the location of a seismic event by means of direct measurements, indirect measurements are needed. A priori information for the mathematical synthesis was obtained from functional equations showing inverse proportions of measured amplitudes, arbitrary effective attenuation coefficients and corresponding coordinates. An original method was applied to process the data. The method providing for passive location of seismic waves sources has been developed; it is called the radial basic method. In the one-dimensional case, a distance is determined on the basis of seismic oscillation amplitudes measured by two seismographs that are located at a known base distance coinciding with the direction to the source of seismic waves. The distance is calculated from the receiver that is nearest to the source. If the base distance and the direct line between the seismograph and the seismic wave source do not coincide, a projection of the distance between the receivers to the given straight line is taken into account.

Three seismographs were placed at mutually perpendicular base distances in a plane (i.e. the two-dimensional space). This allowed us to obtain an analytical equation for determining the direction to the seismic wave source using measured amplitudes. The value of the angle is taken into account when calculating the distance.

For the seismic wave source located in the three-dimensional space, transition equations for combined coordinate systems (i.e. the Descartes (Cartesian)), at the axes of which the seismographs were placed, and the spherical coordinate systems were applied, and analytical equations were obtained for determination of coordinates, such as distance/polar radius, elevation angle/latitude, and bearing angle/longitude.

To analyze the application of the radial basic method of passive location, an absolute error resulting from indirect measurement was calculated. This method is a special case of determining the statistical characteristics of the sought function (coordinates) out of random values, which are the measured amplitudes of seismic oscillations. In the obtained analytical expressions for determination of the mean square deviation of the distance and direction to the seismic wave source, noise from seismographs is taken into account, as well as external noise manifested as microseisms and other interfering seismic waves. For the three-dimensional space, equations are derived for calculation of RMS distance, elevation and bearing angles.

In cases where distances to seismic wave sources, directions, coefficients that factor properties of the medium, and base distances are known, the radial basic method allows us to determine effective coefficients of seismic wave attenuation and capacities of seismic wave sources.

Formation of the geological medium boundaries and patterns is specific, but such specific features have not been fully considered yet. No consideration is given to the nature of periodic variations of various parameters of the geological medium from the surface to the depth of the upper mantle. Remarkable are properties of interblock/interplate marginal structures that ensure steady and quite  contrasting movements of blocks, and it is of interest which processes provide for such properties. Another related question is why insignificant attention is still given to some variations of geophysical fields that might be interpreted as precursors of large-scale fracturing? Degassing (first of all, hydrogen degassing), P–T parameters at any depth level, and pressure of the upper layers determine the crystalline structure of the medium, including layers between blocks. Due to combinations of these impacts, principally new conditions are established, in which  amorphized/irregular and regular structures are formed. Such a twophase system, including a variable number of regular/crystalline and irregular/amorphized phases, may be responsible for specific and unique spatial geological structures, such as the Moho, blocks and ‘subduction’ zones, and variations of their parameters. The stable amorphized structure of the boundary  interlayers facilitates sliding of blocks against each other, which does not permit any control of transfer of movements to rapid displacements followed by strong earthquakes. This article considers the nature of processes that generate amorphized structures in the geological medium and geological consequences of such processes.

The commentary discusses possible directions for further research on the complex of issues arising in the analysis of the interaction of ascending hydrogen flows with the solid phase of the lithosphere and upper mantle.

The article provides review of presentations of the All-Russia Conference with participation of invited foreign scientists «Contemporary Geodynamics of Central Asia and Hazardous Natural Processes: Quantitative Research Results» and the All-Russia Young Scientists Workshop on issues of contemporary geodynamics, which were held on 23–29 September 2012 at the Institute of the Earth's Crust SB RAS in Irkutsk, Russia.

The article provides review about the 10th anniversary of All-Russia scientific conference «Geodynamic evolution of the lithosphere of the Central Asian Orogenic Belt: from ocean to continent», which was held on 17–20 October, 2012 at the Institute of the Earth’s Crust SB RAS in Irkutsk, Russia.

The Mw 6.3 earthquake, that occurred in L'Aquila, Central Italy on April 6, 2009, killed 309 people, 1500 citizens were injured, and 30000 people lost their homes. On October 22, 2012, an Italian court in L'Aquila convicted seven scientists for failing to adequately warn residents before the earthquake struck Central Italy. All are members of the National Great Risks Commission, and several are prominent Italian seismologists and disaster experts. They were accused of involuntary manslaughter, negligence and errors in the assessment of the earthquake precursors and sentenced to six years in prison and payment of monetary compensations to relatives of those killed and injured.