Table of contents

GeoProNH

III National scientific conference with foreign participants "Geodynamical Processes and Natural Hazards"

This issue presents the proceedings of the GeoProNH – III National scientific conference with foreign participants "Geodynamical Processes and Natural Hazards". The conference was held May 27-31, 2019 in Yuzhno-Sakhalinsk, Russia, and considered the following topic areas:

- the seismicity of the Russian Far East and Eastern Siberia;

- the tectonics and geodynamics of the northwestern Pacific;

- manifestations of tsunamis and other marine hazards;

- recent volcanism and methods of its monitoring;

- geological and geomorphological aspects of the coastal assimilation strategy;

- environmental problems and geoecological hazards.

The Sakhalin and Kuril Islands are parts of the Pacific Ring of Fire, so this region undergoes almost all possible geohazards: earthquakes, tsunamis, volcano eruptions, etc. More than 120 scientists, experts and postgraduates from Belarus, Egypt, France, Japan, Kyrgyzstan, and Russia took part in the GeoProNH Conference and discussed the current state of the art and advances in geosciences related to the analysis of natural hazards and/or their preventions. The conference also considered fundamental and applied problems of geology, geophysics, geodynamics, geoecology, oceanology, seismology, volcanology, etc. related to the dangerous natural phenomena mentioned. The Conference Program included four days of plenary and topical sessions, poster presentations, and two days of field geological excursions. The ultimate goal of the conference was to highlight and share the best ways to reduce negative impacts of the above hazards using modern monitoring systems. The published proceedings, hopefully, will serve the same purpose. The issue is addressed to researchers, experts, and students who deal with geohazard assessments and relevant topics of geosciences.

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All papers published in this volume of IOP Conference Series: Earth and Environmental Science have been peer reviewed through processes administered by the proceedings Editors. Reviews were conducted by expert referees to the professional and scientific standards expected of a proceedings journal published by IOP Publishing.

Seismic process is usually considered as a realization of the regime of self-organizing criticality (SOC-model). This model meets, however, definite problems, besides it gives only a statistical description of the seismic regime. The multiplicative cascade model (MCM) treats the seismic regime as an assemblage of randomly developing episodes of avalanche-like relaxation, occurring in a set of similar metastable sub-systems. In the simplest linear variant without memory the MCM is defined by the flow of events and by two parameters characterizing the hierarchical structure and the level of metastability of a geophysical medium. An advantage of such approach consists in a clear physical sense of character of the model. The MCM model b-value behavior is compared with the complex of typical anomalies revealed in result of examination of a large earthquake generalized vicinity (LEGV). The LEGV vicinity is constructed of earthquakes falling into the zones of influence of a large number (300, 500, or 1000) of largest earthquakes. The construction and examination of LEGV gives possibility to increase radically the available statistics, crucially diminish a random component of the seismic regime, and in result to reveal the typical features of pre- and post-shock seismic activity in details. The combined use of MCM and LEGV methods gives possibility to interpret a few features of the seismic regime and to suggest the typical scenario of the fore- and aftershock regimes of seismicity. The possibilities of application of the obtained results for earthquake prediction are discussed.

The article reports on instrumental monitoring of rock deformation in the South Baikal geodynamic test site. Based on the analysis of the time series of data sets, two groups of strain components are distinguished by differences in their origin and wave properties. Strain components in the first group are caused by external factors, such as lunar-solar tides and atmospheric pressure variations. The second group includes non-periodic, random and periodic (constant) components generated by internal tectonics. Non-periodic components are manifested as single deformation impulses that differ in intensity and form, and are related to slow displacements along large active faults, which occur outside the monitoring sites. Besides, non-periodic components are related to fast displacements at block interfaces within the monitoring sites. The periodic (constant) component is related to the India-Eurasian collision. It is represented by slow strain waves, which lengths amount to 400–500 m, with amplitudes of few microns, and periods of (1-3)·10⁻⁴ Hz. The strain wave directions and rates of their migration in space vary with time. The identified trends of changes of the wave parameters in the South Baikal geodynamic polygon can be related to the preparation of a strong earthquake.

The earthquakes and aftershock sequences catalogue of 13 moderate earthquakes occurred in the Tian Shan and the Pamir Mountains from 1983 till 1997 have been examined from the point of view of non-equilibrium thermodynamics using Tsallis statistics and its compliance with Omori-Utsu power-law. It has been shown that the earthquake sequence is the system with memory and long-range correlations. The Tsallis parameter q for the aftershock sequences is larger than the q, calculated for all the earthquake catalogue, which indicates the preservation of increased long-range correlations during the aftershock sequence. Dynamic definition of the parameter q of the four events has demonstrated the sharp increase of the long-range correlations in the target region before the main event and the sharp decrease straight after it followed by return to the average value observed before the mainshock. It has been illustrated that the parameters of the researched aftershock sequences are described by the power dependences and follow the Omori-Utsu law.

The study of geodynamic processes observed in the Earth's crust at densely populated and commercially developed areas in the east of Russia and China is of great importance for their sustainable development. The research results available show that not only natural, but also man-made geodynamic events associated with mining operations reflect the global geodynamic processes. Geodynamic events that occurred while mining in impact-hazardous areas allowed to identify some common features in the manifestation of natural and man-made geodynamic events in the eastern regions of Russia and China. Thus, both natural and disastrous technogenic geodynamic events (tectonic rock bursts, induced earthquakes, cracking on the earth's surface) have positional connection with the linear zones of earth's crust modern destruction (block boundaries and faults). Existing tectonic faults get re-activated during major geodynamic events, i.e. they get displaced in response to the mining operations. Areas hazardous for manifestation of geodynamic phenomena can be defined by geodynamic zoning method which can be used to draft the development programs for the eastern regions of Russia and China

This paper presents the results of the stress inversion in the Earth's crust in the Japanese seismic focal zone after the Tohoku earthquake of March 11, 2011. The stress tensor parameters are determined using the method of cataclastic analysis (MCA) of discontinuous displacements. The reconstruction of the stress state is based on earthquake focal mechanism data for magnitude range (Mw) 3.0–6.0. The calculations are performed at six depths. The 2011 Tohoku earthquake brought significant stress changes in the upper layers of the lithosphere of the continental slope (0-30 km). These changes have led to the emerging of extensive areas of horizontal extension here. The areas with changed geodynamic regime were not reduced over the past few years. The magnitude 9.0 Tohoku earthquake was a catastrophic mega earthquake and in this case the presence of an anomalous state of stress may take a long time.

In this work we estimate level of seismic noise at Kyrgyz Network's (KNET) high-mountain stations for 19 years of the time this network operated in real-time mode (1999-2017). To do that for each channel (E – west-east, N – south-north and Z – vertical, all with 100 Hz sample rate) of each station we made fifteen-minute (900 seconds) segments of seismic noise. We took such segments for different seasons (March, June, September, December) and for various times of day (00, 06, 12 and 18 hours UTC) for the whole 19 years. We analyzed probabilistic power spectral density heatmaps and found out some features of KNET's high-mountain station's operation. These features depend on season-wise weather changes. The worth month for all stations is September. In general, when weather is favorable these stations can be characterized as low-noise ones and their data may be used in various researches.

In the present work we show a fundamental possibility of a short-term prediction of strong shallow-focus earthquakes in the Southern Sakhalin (on the Krillon earthquake example, 23.04.2017, Mw=5.0). Retrospective modeling of earthquakes sequences from 2013 to 2017 based on the method of self-developing process (SDP) and the catalogue data of the local network has required. An auxiliary tool was used to improve the accuracy of the SDP estimates. It is a medium-term earthquake prediction method called LURR (load-unload response ratio). The previous results were improved using different sample data in the zones of active fault structures. This avoids ambiguity in the choice of the computational domain for SDP calculations. The zone of maximal anomalous levels of LURR coincides with that one we obtained a solution by the method of SDP. It happened 77 days before the earthquake. When compared with average estimates by the LURR method (two years), the prediction time was concluded to go down by 11 times.

A new processing of materials on variations of seismicity of the Bishkek geodynamic polygon (BGP) under effect of electromagnetic (EM) soundings of geological medium has been carried out. The revision of these materials is topical due to following issue. During the period of 1983-1989 the disharges of the capacitor battery (so-called cold runs) were used for supply for EM soundings in addition to the MHD generator launchs (hot, or fire runs). Moreover, alternative source of EM soundings by bipolar current pulses (namely, the ERGU-600-2 equip) was used in the times of 90s. But previous studies paid low attention to electric injection to Earth Crust besides MHD generator hot runs. Motivated by such state of the art we have analysed temporal dependence of Benioff strain on the territory of the BGP in the overall period of EM soundings (from 1983 up to now). The alterations of EM soundings sources and operational modes have been taken into account. But our approach has reveal no no noticeable change seismic regime (by the Benioff strain data) during the nineties in close surrounding of the injecting dipole.

To conduct complex geophysical observations in the area of the Central Sakhalin Fault, an experimental geophysical test site was created, including a broadband molecular electronic type station and a new development of the Molecular Electronics Center - molecular electronic hydrophone. A module for placing a molecular-electronic seismometer at the test site has been developed and arranged. The noise level of the seismometer was analyzed and compared with the reference data. The results of hydroacoustic observations of weak earthquakes in the area of the Central-Sakhalin fault using a molecular-electron hydrophone are presented. The characteristics of the recorded acoustic emission signals from earthquakes perceived by the hydrophone station (frequency spectrum, arrival times of seismic waves) are investigated. The issues of operation and maintenance of molecular-electronic sensors with seismic signal data logger at various stages of seismological observations (setting up equipment, acquisition and storing data) were considered. The analysis of recording capabilities of seismic equipment was performed. Conclusions about the advantages and disadvantages of molecular-electronic sensors and their use on Sakhalin are made.

The present study presents the results of the stress tensor inversion in the Sakhalin-Island and adjacent territories. The method of cataclastic analysis of discontinuous displacements has been used to perform the stress reconstruction. The stress inversion has been performed on the basis of local focal mechanism solution catalog of earthquakes, NEID and Global CMT Project data. The calculations are carried out at three depths levels (0–6 km, 6–12 km and 12–18 km) for magnitude range (Mw) 3.0–7.0. The results of the stress reconstruction allowed us to obtain the new specific features of the tectonic stress field: orientation of the principal stress axes, stress ratio or Lode-Nadai coefficient and the types of stress (the geodynamic regimes). The tectonic stress field is less stable at depth between 6 and 12 km.

According to the various scale GPS measurements, the process of collision between India and Eurasia is still ongoing and is reflected on Central Asia territory. The maximum velocity of shortening on northern component between India and Asia is ∼35 mm/year; the longitudinal (east-west) extension of the Tien Shan is ∼20 mm/year. The maximum deformations of shortening ∼15 mm/year along the north coordinate operate in a narrow fault zone between the Pamir and Tien Shan. Not on all Cenozoic (neotectonic) faults occur modern movements of the earth's crust, these faults may have separate segments of active at different times. The general kinematic tendencies of modern movements correlate well enough with the general kinematic structure of neotectonic faults. In the fault zones at distances from the first hundreds meters to the first kilometers, intense elastic changes in the baseline lengths up to 4 cm (strains of 10^–4) can occur within a week and up to 3-5 months. Such high-frequency elastic events have a different character of manifestations and are 2-4 orders of magnitude greater level than stable many years' residual deformations.

We computed seismotectonic deformations (STD) of earth crust in Pamir and neighbor areas. We used ISC (International Seismological Centre, London) catalogue for average STD rate computations, including more than 25000 earthquakes that took place between 1934 and 2016. STD tensor axes' directions were computed based on hypocenter focal mechanisms of 3049 earthquakes that took place between 1946 and 2018. We haveplotted maps showing distribution of STD intensity and number of earthquakes for various ranges of hypocenters depths, and map showing horizontal part of STD tensor. Finally we analyzed different deformation conditions in South Tien-Shan and Pamir.

In the port harbors there are reoccurring a reciprocating movements of water, which a connected with strong waves at sea. Threatening the safety of ships and berthing facilities, these movements, called harbor oscillations, are caused by the infragravity waves. They occur when their periods are close to the periods of eigen resonant oscillations of the water area. As a result of the observations, it was found that the seiches modulated with the frequency of tidal waves. This phenomenon cannot be explained by analogy with the modulation of infragravity waves. Observations show that the primary reason is an enhancement of energy loss over the low-tide surfzone bottom profile, while in the port harbour significant currents are observed only in the harbor entrance zone. It is shown that the reason of modulation is a change in the water level in the harbor, which occurs nonlinearly. Using the Duffing equation, the dynamics of a nonlinear dynamic system a liquid oscillating in a port under the external excitation by tidal waves and swell, is analyzed. It is shown that under the influence of swell at the harbor entrance can lead to chaotic vibrations in the harbor, which can be dangerous for ships.

Possibility of a tsunami as a result of an earthquake is estimated by magnitude and geographical criterion now. The earthquake is considered tsunami-danger if his epicentre gets to a tsunamigenic zone, and intensity exceeds the set threshold value of magnitude. The solution of such task as specification of magnitude and geographical criterion for the announcement of alarm of a tsunami in the Sea of Japan and in the water area of the Pacific Ocean to the east of the Japanese islands is extremely relevant. For the purpose of specification of magnitude and geographical criterion of tsunami risk of earthquakes in these areas the author executed a series of computing experiments. During the computing experiments the centres of real historical tsunami in these water areas were modelled. At creation of the model centres of a tsunami the Okada model was used. Based on the analysis of statistics of historical tsunami and results of numerical modelling by the author the redundancy now in use by Service of warning of a tsunami in the Far East of Russia magnitude a tsunami risk threshold is shown.

The problem of the tsunami source reconstruction from the remote measurements of an arriving waves in the deep-water tsunamimeters is considered as an inverse problem of mathematical physics in the class of the ill-posed problems. The latter determines the inevitable instability of the numerical solution. We propose a method providing more control on the numerical instability of the solution. The DART buoys data allows one to apply the linear shallow-water theory for the wave propagation and the r-solution method for the tsunami waveform inversion. The applied approach is independent from the earthquake source characteristics, because the only observed tsunami waveforms and a roughly estimated tsunami source area are used. A good coincidence of observed and computed tsunami waveforms was a criterion of the quality of the inversion. In this paper we study the 16 September 2015 Illapel (Chile) event and conduct a reconstruction of a tsunami source.

According to observations of the waves in 2006 in the harbor of Kholmsk, chaotic vibrations were detected. Studies have shown that with an increase in the amplitude of external excitation, wind waves and swell coming to the entrance of the harbor, the energy of oscillations in the system also increases. For incoming waves higher than 3.5 m the spectrum changes, the energy of movements in the harbor increases significantly in a wide range of periods and reaches the level of energy of the harbor's eigen oscillations, which in this case are practically not allocated. The authors suggested that at large amplitudes of waves at the entrance of the harbor the fluctuations become chaotic. Verification of this assumption was performed on the basis of numerical simulation using the Duffing equation with external periodic excitation. The simulation showed the possibility of chaotic vibrations in the harbor. The system has intermittent chaotic and periodic modes of oscillations with increasing amplitude of external excitation for a wide range of periods and increasing the energy of chaotic vibrations.

A tsunami in the ocean, according to one idea, is a long wave with a practically unchanged period and a relatively slow attenuation. According to others, the dispersion affects the evolution of a tsunami, the wave period increases with time, and the amplitude attenuation is more rapid. This study investigates the transformation of tsunamis from source to coast, including the change in amplitude and duration of the head waves with distance. It is shown that the dispersion does affect the evolution of the tsunamis. The moment of dispersion manifestation depends not only on the magnitude of the earthquake that caused each tsunami, but also significantly on the depth of the ocean in the focal region.

On Aug. 29, 2016, the tropical cyclone Lionrock was reported to turn into an extra-tropical storm and go to the shore of the Primorsky Region as monitoring shows, which brought about significant precipitation growth recorded in the north of the coast. Many surveys show the tropical cyclones in this area to transform into extra-tropical ones and become powerful mid-latitude storms with significant damage to coastal and maritime areas. The paper uses WWLLN (World Wide Lightning Location Network) data to study the thunderstorm activity while the tropical cyclone reaches the typhoon level with the maximum wind velocity. This made it possible to identify parameters' variations of thunderstorm activity during atmospheric vortex phenomena. It also enabled us to determine the emergency probability due to a thunderstorm.

Significant wave heights and most probable wave heights in the nearshore areas of the Southern Kuril Islands are considered in this paper. These characteristics were obtained from data of in-situ measurements of hydrostatic pressure in the depth range from 5 to 25 m. The measurements have been performed in 2008 and 2009. It is shown in the paper that relatively calm sea surface was observed in time period from July till first half of September. Most probable wave heights varied from 0.17 m to 0.27 m and maximal values of significant wave heights varied from 0.75 m to 1m in the depth range from 15 to 25 m. For depths less than 15 m most probable wave heights varied from 0.05 m to 0.1 m and maximal values of significant wave heights varied from 0.68 m to 1m. Time period from second half of September is characterized as stormy period. Maximal values of significant wave height reached 5 m at that time and most probable wave heights varied from 0.1 to 1 m depending on depth and location. Period from January till April can be characterized by high number of moderate storms with maximal value of significant wave heights 1.8 m and most probable wave heights from 0.13 to 0.33 m.

The present paper is a comparative study of geochemical characteristics of the emissions of the Yuzhno-Sakhalinsky mud volcano and the sediment-hosted hydrothermal systems Salton Sea and Lusi. The comparative analysis was performed using the data on the content of Cl, Br, SO₄, Li, Na, K, Ca, Mg, B, Ba, Sr, Si, oxygen-18 and deuterium in the discharged fluids, as well as on the content of CO₂, C₁-C₅, carbon-13 in CO₂ and CH₄ in the released gases. It showed the absence of any distinct systematic differences in geochemical parameters between mud volcanoes and sediment-hosted hydrothermal systems. This suggests, inter alia, a need for a detailed geochemical classification of mud volcanoes, which to this day has not been elaborated.

The article presents the results of researches of thermal waters of South-Eastern solfataric field of Ushishir volcano (Yankicha Island, Central Kurile Islands) in 2007 and 2015. Detailed studies of the physicochemical properties of the hydrothermal springs of the volcano were begun in 1950-60 years. Modern studies have confirmed the stability of physical and chemical parameters of hydrotherms. Modern thermal waters (temperature up to 100 °C), as before, can be attributed to acidic (pH 2.8-3.6), highly mineralized (TDS 23-36 g/l), sodium chloride. The chemical composition and ratio of the main macroelements of hydrotherms are close to the sea waters of the region. The uniqueness of these waters distinguishing them from other coastal hydrotherms of the Kuril Islands is their high acidity. The increased content of balneological elements (Br – 107 mg/l; B – 36 mg/l; I – 0.5 mg/l) in hydrotherms determines their high therapeutic value, which allows them to be used in the treatment and prevention of a wide range of diseases.

Volcanic lakes are of particular interest to geomorphologists and other professionals due to the diversity of the basins forms and the very dynamic development of lake systems. The origin and evolution of these water bodies are closely related to active volcanic and post-volcanic processes, they are characterized by rapid changes of shape, level, composition of water and characteristics of the coast. Usually bounded by craters, calderas and in the immediate vicinity of volcanoes, these lakes present a kind of by-product of volcanism. In the Kuril-Kamchatka region, two types of lakes can be distinguished: 1) dynamically developing young, some of them ephemeral, located on active volcanoes, in active craters. In these lakes, as a rule, there are active gas-hydrothermal manifestations, and their waters are highly mineralized; 2) stable (relict) lakes in the calderas of dormant and extinct volcanoes. Lakes of this type usually do not have explosive funnels or active gas hydrotherms, and the water in them is slightly mineralized. It suggests a much more ancient age and the decreasing of post-volcanic activity in caldera depressions. Lakes of different types can exist close to each other and form a single communicating systems.

For the first time, data have been obtained on the concentrations of REE in the subsurface fluids of the Yuzhno-Sakhalinsky mud volcano, as well as in the spring at the foot of this volcano. It has been demonstrated that the REE concentrations in the waters of the studied volcano are significantly higher than in the waters of the mud volcanoes of Junggar Basin. It has been ascertained that the total concentration of REE in mud volcanic waters does not depend on their mineralization, yet it correlates with the concentration of Al. This is probably caused by the sorption of REE on the fine particles of clay suspension. The obtained ranges of REE have a high positive Eu anomaly, which is likely to be an artifact due to the relatively high concentration of Ba in the studied waters.

The data characterizing volcanic activity in the Kuril Islands in 2018 are given on the basis of satellite and visual data. The Ebeko volcano (Paramushir island, the Northern Kuriles) and Sarychev Peak volcano (Matua Island, the Central Kuriles) were active in the Kuril Islands. On Ebeko volcano a weak (to moderate) explosive eruption occurred, it expressed in regular steam and ash-gas emissions (only about 800 with a height from 2 to 5.5 km). Sarychev Peak volcano was characterized by a manifestation of weak (to moderate) explosive activity (during the period from September till October there were at least 10 emissions to a height of 2 to 4.5 km). Due to the relatively low emission height and low ash concentration, the activity of Ebeko and Sarychev Peak volcanoes in 2018 did not pose a serious threat to international air routes, but could complicate the work of local airlines.

New high-precision data on the surface destruction rates of a co-seismically raised bench as a result of the Nevelsk earthquake in August 2, 2007, Mw = 6.2 in Nevelsk allowed to determine that the destruction of subvertical coastal cliffs occurs with the speeds nearly an order of magnitude larger, than the speed destruction of subhorizontal bench surfaces. The role of wave influence in the benches formation is mainly reduced to the mobilization and removal of debris obtained as a result of frost weathering at negative air temperatures. High-precision orthophotos and 3D models of high coastal ledge composed of volcanogenic-sedimentary rocks made it possible to identify the cliffs destruction mechanisms with non-uniform strength and to determine their quantitative parameters. It was found that the destruction occurs along structurally weakened zones, as well as during the collapse of large rocks blocks due to the formation of wave-breaking holes in rapidly destructing tuffs. Suffosion in tuffs and their contacts significantly weakens the solid characteristics of volcanogenic-sedimentary mountain massives. The retreat of the coastal scarp brow formed by volcanogenic-sedimentary rocks can reach several meters per year under these conditions.

The paper presents the results of a comprehensive analysis of GPR data and geophysical well survey data (gamma-ray logging and self-polarization potentials) to study the 3-D spatial structure of the Daginsky hydrothermal system discharging zone (Sakhalin Island) and its hydrogeological situation. According to the GPR method, the paleo-valleys were identified, the morphology of which indicates the presence of runoff hollows, the accumulation of sandy-aleurite-clay sediments covered with peat formations. It can be concluded that the caprock in this area consists of a pack of water layers and permeable zones. Based on the data of geophysical studies in wells, three zones can be distinguished, each of which is characterized by the corresponding values of gamma activity and changes in the potentials of its own polarization. All this helps in identifying permeable thermally conductive zones. The data obtained are of practical importance.

Changes in coastal retreat rates, both spatial and temporal, are considered at the area of Kharasaveyskoye gas and condensate field for the period before the exploration till now. In the study area, the presence of permafrost makes the erosional coasts vulnerable to rising temperatures. The increase in air temperatures contributes to the thawing of coastal sediments and their accelerated destruction. And a decrease in sea ice area potentially increases the wave fetch. The rapidly changing climate of the Arctic should influence the processes of destruction of frozen coasts. At West Yamal Peninsula near Cape Kharasavey the average coastal retreat rate is 1.1 m per year (1977-2016) for 7 km of coastline. Based on the analysis of multi-temporal aerial and space images, it has been established that the maximum retreat rates are typical of coastal segments composed of icy sediments. As for temporal variability, the maximum rate of destruction was observed in 1977-1988 (up to 6.5 m per year) immediately after the beginning of economic development of the territory. In this key site, human impact affects the rate of coastal destruction more than variations in hydrometeorological parameters.

The coastal zone of Pacific Russia (administrative areas of the Far East with access to the ocean) is characterized by many dangerous natural processes. However, due to the low population density of the region, their impact on nature management often goes unnoticed. This sometimes gives a false impression of their lack of strength compared to similar processes in other more populated areas of the world. However, if the population density in the coastal zone of Pacific Russia corresponds to the indicators of Japan or Indonesia, the consequences of their occurrence in most cases would be catastrophic. An inventory of hazardous natural processes in the region was carried out. The intensity of their manifestations in other parts of the world was compared and a division of these processes according to the degree of their danger to the region was made. In the category of the most significant processes, the force of manifestation of which corresponds to the maximum possible values observed on Earth, or is approaching them includes earthquakes, tsunamis, volcanic eruptions, avalanches and cryogenic processes. The second group includes mudflows, aufeises, river erosion, abrasion, landslides, screes, landslides, subsidence and suffosion. The third group (the probability and intensity of which within the coastal zone of Pacific Russia are minimal) includes gully erosion, sheet erosion, rock streams, heaving, shrinkage, karst and aeolian processes. If we compare with other Russian regions, some processes (volcanic eruptions and tsunamis) are distributed exclusively within the coastal zone of Pacific Russia, others (earthquakes, aufeises, abrasion, rock streams, cryogenic processes) have a generally higher intensity, the importance of the third (karst, subsidence, etc.) is obviously lower than in other Russian regions.

Explosive volcanism is equally important as the features of neotectonic and modern movements for the development of the Kurile Islands coast, as it led to the afflux of hundreds of millions of cubic meters of pumisopyroclastic material and tephra into the wave processing zone of coastal zones of the Pleistocene-Holocene. Morphometric, georadar and paleogeographic studies of the coastal-sea relief of Iturup Island allowed to determine several levels of marine terraces in the pyroclastic sediments of the Late Pleistocene-Holocene, and also the presence of a buried sea strait that existed at least in the middle Holocene. Taking into account the values of deformation of the terrace levels, the depth of the strait was 10-15 meters. Volcanic-tectonic deformations connected with eruptions near the central part of the Vetrovoy Isthmus led to the collapse of pumice packs at the section basement of the sea coastal ledge with a layer of beach material on the roof (LU-9223-6320 ± 100, cal. Year BP). Thus, in the mid-late Holocene, after the sea level was risen to the nowadays levels, at least two more pyroclastic series were deposited, the last of which one is dated 1050 ± 70 cal. BP – LU-8685.

The airborne magnetic data is considered as one of the best methods to delineate the depth to basement layer. The airborne magnetic survey data obtained from the Egyptian Nuclear Materials Authority. Data is accurately processed, interpreted. Two-dimensional (2D) modeling was performed by GM-SYS, along one selected profile yielded from RTP map. In addition to that, three-dimensional (3D) Euler Deconvolution method was performed to delineate the depth to basement layer. Euler solutions were applied on RTP Grid by structural indexes 0, 1, 2, and 3 to select the best solution. The sedimentary succession of the study area is created using seismic data and well data. Petroleum system model was established to predict the locations of hydrocarbons within the study area. The results of PetroMod confirmed that the area is very promising for hydrocarbon aggregations, and also new hydrocarbon aggregations have been discovered.

Among dangerous natural processes in the Baikal region we emphasize aeolian processes of high intensity which is due to dust storms caused by hurricane winds. The factors of the process development were studied, and special attention was paid to the wind regime and seismic activity, as well as to the catastrophic consequences and damage. We analyzed the number and duration of dust storms, calculated the deflation potential of the wind and the energy of the air flows. The morphology of aeolian relief forms, both deflationary and accumulative was studied. We forecasted sand dune drifts based on the analysis of the charted sand rose. Differences in structure, mechanism, and intensity of the processes are revealed depending on the hydroclimatic conditions during the monitoring period. In connection with global climate change, which is manifested in the Baikal region by an increase in the number of arid years of observations (35%), and the frequency of emergency situations associated with natural processes increases. It is necessary to continue the monitoring of aeolian processes in order to create long-term and short-term forecasts to avoid catastrophic consequences.

In the present paper we have addressed the issue of identification of mud volcanic activity based upon the vegetation, its structure and dynamics, as well as the structural peculiarities of woody plants. The study was conducted using an integrated approach which includes: the description of vegetation and the structural analysis of woody plants that grow at various distances from the eruptive centre of the volcano. The obtained data on the vegetation suggest that the Yuzhno-Sakhalinsky mud volcano is a far more extensive landscape feature that it was considered before, with an eruptive centre which changes its location every 150-300 years.

In the present paper, the results of the study of the structural peculiarities of Betula ermanii growing in the setting of the Yuzhno-Sakhalinsky mud volcano are presented. A statistical analysis of the structural parameters of young stem bark has been conducted, which has made it possible to distinguish features dependent on extreme environmental conditions. Parameters of young stem bark have been elicited, which have higher than normal values: the thickness of periderm and phellem, the diameter and length of sieve tube elements, the specific number of crystals in bark parenchyma, the specific area of sclerenchyma in the bark. The structural response of the young stem bark of Betula ermanii is likely to have an adaptive nature.

This paper presents the results of the study of lichens in Yuzhno-Sakhalinsk and its surroundings. To assess the epiphytic cover the method of occurrence measuring on the tree trunks with the help of a frame 10×40 cm (400 cm²) was used at 15 locations within the study region. Zones and exposure gradient were defined through clustering and ordination method. 47 species of epiphytic lichens and their distribution characteristics in various areas of human impact were identified. Populus maximowiczii had been selected as a phorophyte as it prevails in urban vegetation and naturally grows in the flood plains where control plots were set up.

The paper presents the features of the snowmelt dynamics of snow mass in the urbanized area in different altitudinal zones, with different regimes of anthropogenic load. The temperature distribution in the snow layer data analysis is carried out. The capabilities of snow mass monitoring system analysis according to the periods of active water loss prediction is carried out.

The article is devoted to the formation of modern composition of the adventive and the invasive component of flora in Sakhalin Island. More effective expansion of the alien plant species was in the 20^th century during the colonization and the scale development of the island's natural recourses. Today there is a new splash of the alien plants drifting due to development of offshore oil and gas projects and intensive traffic flows. As a result, anthropogenic transformations of many years Sakhalin natural landscapes caused the expansion of adventive flora to 240 taxa, where 26 species are the invasive and widespread on the island.