Vol 17, No 2 (2021)

A description of the seismotectonic situation of the area at the Rostov Nuclear Power Plant (NPP) industrial site area is given. It is noted that despite the location of the NPP within the stable platform area, there is a possibility of rare strong seismic events in the zones of intersection of deep faults of the north-western and north-eastern directions, where superdeformations of the crust (2 × 10−5... 7 × 10−5) with a formation time from several days to several months are possible. Estimation of the maximum possible magnitude for faults of an unclear degree of tectonic activity Мmax, performed by the Geophysical Service of the Russian Academy of Sciences (GS RAS) according to the maximum gradients of the geoidal height field gives Мmax a magnitude value of up to 5.2. Taking into account the expression for the empirical deformation radius of Dobrovolsky RD = 100.43M, magnitude 5.2 approximately corresponds to a radius of 170 km, within the IAEA requirements (up to 200 km). For the area of the NPP industrial site location with such radius, where earth’s surface deformations are possible, scientifically based data on the geodynamic situation should be obtained. The project of the GPS network developed by the GS RAS was considered in order to assess seismogeodynamic activity of the Rostov NPP location area. The efficiency of the GS RAS GPS network can be improved by installing five additional permanent GPS stations of the Southern Scientific Centre of the Russian Academy of Sciences (SSC RAS) and introducing a new technology for processing satellite measurements based on multidimensional statistics. An example of the current GPS monitoring system of the SSC RAS, created jointly with Yuzhmorgeologiya JSC and Kuban State University on the basis of a regional GPS network in the Taman Peninsula region, is presented. In the course of observations during the period of increased seismic activity in 2017–2018 42 earthquakes were recorded, of which a catalog of 12 seismic events with magnitudes from 3.5 to 4.7 and epicenters on land and in the Azov and Black Seas was compiled. The definition of the integrated indicator of the stressed-deformed state of the crust is given on the basis of mathematical methods of multidimensional statistics. Analysis of time variations of the integrated indicator value in the low-frequency band shows an increase in its amplitude 20–40 days before the earthquake within the GPS network.

The mouth area of the Don is a key area of the Sea of Azov basin, where complex processes of interaction between river and sea waters take place. Wind-induced water level fluctuations and the related inflow of transformed sea waters into the Don River delta branches are especially manifested here. Under certain hydrometeorological conditions, the salty waters of the Taganrog Bay penetrate even into the mouth of the Don River, where fresh water intake is located. The paper describes a mathematical model of the process of the salt water inflow of the Taganrog Bay into the Don River delta. The hydrodynamic component of the model is based on the equations of Saint-Venant, written in characteristic form. The transport component is described by the one-dimensional convectiondiffusion equation in the case of a conservative substance. The mouth section of the Lower Don from the village of Razdorskaya to the mouths of the Don River delta, including the Stary Don, Mokraya Kalancha, and Bolshaya Kuterma branches, was chosen as the calculation area. The problem is solved by finite-difference methods using implicit schemes. The calculations were carried out taking into account the meteorological situation in the period from 23 to 27 September 2014, when the strongest wind surge in recent years was observed. The results of calculations of the water flow rate and salt concentration in the Don branches depending on the water level in the Taganrog Bay are presented. Comparison of the calculated values of the salt concentration in the Azov port area with the observed values showed that the presented mathematical model adequately describes the process of salt water inflow from the Taganrog Bay into the main branches of the Don River. At the same time, the model gives an idea of the general trend of possible salinization of the Don River delta during surges, which can be used for prediction of such phenomena and taking executive decisions for sustainable water supply of seaside cities.

The presented new research data reflect changes in the natural environment in the region. Special attention has been given to studying anthropogenic load, which significantly affects the ecosystem of the region over the last 200–300 years, and especially since the middle of the 20th century when the Don River flow has been regulated. The bottom sediments in the eastern area of the Taganrog Bay are characterized. The study results suggest that changes in the depositional conditions in this area of the Sea of Azov occurred about 4.5 thousand years ago. We analyzed data on the change in the suspended sediment flow since the Don River regulation and the transformation of the river runoff on the southern flank of the Don delta, caused by the Azov-Don sea canal put into operation in 1927. We concluded about the degradation of that part of the Don delta. Malacological studies revealed bottom fauna presented with marine, brackish (Ponto-Caspian), and freshwater species, in sediments of the eastern part of the Taganrog Bay and the adjacent area of the Don River delta. The soil cover in the Don River delta has been studied with the subsequent ranking according to the degradation factor.

The developing scientific foundations issue is relevant and topical today for the application of digital economy technologies for monitoring and forecasting hazardous processes and ensuring the safety of the population and coastal infrastructure. Especially it is topical to the implementation of the theoretical principles of monitoring for aquatic ecosystems which would include both classical, field observations and new technologies of contactless monitoring. The goal of this study is to solve this issue in terms of improving the characteristics of reliability and “openness” of systems. The authors of this article have developed the structure of a decentralized distributed system without hierarchical subordination as well as methods and algorithms for the functioning of a distributed network of sensors and a mobile robotic complex. MRC is the part of this system. MRC allows collecting data on the state of the environment by means of on-board sensor subsystems and collecting data accumulated by telecommunication isolated fragments of a distributed network of smart sensors in remote and hard-to-reach places using distributed computing and elements of fog computing. The effectiveness of the proposed model and method is achieved through the use of a control system, the multidimensional digital control device of which has a sufficiently high order. Algorithms of calculating the values of control actions are obtained by using decomposing control and the method of analytical synthesis of systems with output and action control. The robustness property to deviations of uncertain delays in the communication channels of each MR with the leader is achieved by using the properties of the proposed polynomial control equations. The proposed approach can be used to create digital control systems for both one-dimensional and multidimensional objects (multirobotic complex) which can be used to place sensors for monitoring and diagnostic systems in various fields of application.

The article presents materials about a large-scale storm and flood in the Caspian Sea that occurred on November 10–13, 1952, and the measures taken by the Soviet leadership to eliminate its consequences. The article is based on data from the archival funds of the Central State Archive of the Republic of Dagestan – the resolutions of the Council of Ministers of the USSR, the Council of Ministers of the RSFSR and the Council of Ministers of the Dagestan ASSR, which had a secret stamp. These materials are introduced into scientific circulation for the first time, the research topics presented in the article have not been studied. The storm wind of the east and southeast direction in the Caspian Sea reached 15–28 m/s, the surge height was 1.5–4.2 m. As a result of the catastrophic surge, a strip of land up to 35 km wide from the water’s edge appeared under the water. The natural disaster affected the Astrakhan, Grozny and Stavropol regions, the Dagestan and North Ossetian ASSR of the RSFSR, and the Guryev region of the Kazakh SSR. The analyzed documents present liquidation measures to restore the damaged infrastructure of the flooded areas and conduct rescue operations. The central state administrative bodies and administration of the USSR regulated and monitored the restoration activities in the affected regions caused by this natural disaster. The Soviet leadership promptly helped the victims, preventing the widespread dissemination of information about the natural disaster. Various ministries took part in the liquidation activities, allocating the necessary funds and materials to carry out work to restore the damaged premises, warehouses, institutions, and residential buildings. Operations were organized to rescue people and the fishing fleet in distress during the storm in the Caspian Sea. About 15 million rubles were allocated to eliminate the catastrophic consequences. The banking sector of the USSR aided in the form of loans in the amount of about 11 million rubles for construction with a delay in repayment of 2–3 years. The affected regions were provided with industrial materials, goods and equipment for restoration work. Along with the provision of direct assistance, part of the goods was provided based on the return of their value. The storm inflicted the most devastating consequences on the coastal territories of the Astrakhan region and the Dagestan ASSR of the RSFSR, as well as the Guryev region of the Kazakh SSR.

30 мая 2021 г. исполнилось 80 лет крупному российскому и советскому ученому, выдающемуся математику и механику академику Владимиру Андреевичу Бабешко.