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Based on comprehensive analysis of geological, geochemical, and paleotectonic settings, the conditions for the formation of Neoproterozoic oil and gas source rocks of the Earth are analyzed. A brief review of oil and gas fields in Eastern Siberia, China, the Middle East, Africa, and Australia is given, with Riphean and Vendian terrigenous and carbonate source rock. An overview of the oil and gas bearing basins of the world and a stratigraphic reference of the Neoproterozoic strata discovered within them, containing proven and suspected oil and gas source rocks, are given.The formation of Neoproterozoic oil and gas source rocks is analyzed in a complex way: simultaneously from the point of view of paleotectonics, paleogeographic and paleoclimatic conditions, paleobiological diversity and geochemical conditions. As part of paleotectonic analysis, the results of plate tectonic reconstructions for the Neoproterozoic stage are presented in accordance with one of the most currently relevant geodynamic models. Paleogeographic events and paleoclimatic conditions are described in the context of the specifics of the formation settings of carbonate-terrigenous oil and gas source rocks. In particular, the reasons for the accumulation of sediments enriched with organic carbon in the interglacial epochs of the Neoproterozoic and possible mechanisms for maintaining conditions favorable for their accumulation are considered. The conditions for the accumulation of oil and gas source rocks are also linked to global paleobiological pre-Phanerozoic events, and the analysis of the geochemical data of rocks makes it possible to characterize and correlate Neoproterozoic oil and gas source rocks on a global scale. On the basis of such a comprehensive assessment, a conclusion was made about fundamentally similar geological conditions for the formation of Neoproterozoic oil and gas source rocks in oil and gas bearing basins.

In this work, the influence of various cosmic factors (gravitational influence of the Moon and the Sun, solar activity, the Earth’s rotation) on mud volcanic activity was analyzed for the first time. The analysis was carried out mainly on the example of mud volcanoes in Azerbaijan, for which there is the largest and most complete catalog of eruptions (431 events over almost 210 years). It has been found that the activity of mud volcanoes can increase after syzygial tides, when the Earth is in line with the Moon and the Sun (their tidal forces are summed up in this case). The response of mud volcanoes to the tidal influence of the Moon is delayed by 5–10 days. It is also found that the number of mud volcanic eruptions is distributed unevenly throughout the year with maximums in March–June and September–October. The presence of these maximums may be due to a change in the distance between the Sun and the Earth and variations in solar tidal forces during the periods of perihelion and aphelion. At the same time, the response of mud volcanoes to the tidal influence of the Sun is delayed by several months and is quite strongly extended in time. It was revealed that there are fluctuations in mud volcanic activity with a period of 14–20 years, which do not coincide with the cycles of solar activity (with periods of 11 and 22 years), although some researchers talk about a connection between solar and mud volcanic activity. It is possible that the indicated fluctuations in mud volcanic activity are related to the main harmonic of the Earth’s nutation (18.6 years). It is shown that the maximum number of mud volcanoes on the Earth falls on the latitudinal belts of 30–45° N and 10–15° N (about 22 and 46 % of the total number of volcanoes, respectively). In the southern hemisphere, the largest number of volcanoes (about 3 % of their total number) is located within the boundaries of 5–10° S.

The Pamir salient is a key part of the Himalayan–Tibetan Plateau orogenic system and has undergone intense tectonic deformation during the India–Asian collision. Delineating the Cenozoic kinematics and geodynamics of the Pamir salient requires a comprehensive understanding of the active arcuate structures along its frontal margin, from the perspective of the multi-spatiotemporal evolution of deformation patterns. Here, we reviewed the deformation rates of the major structures at different timescales, reanalyzed the published Global Positioning System velocities, and examined the present-day seismicity to constrain the kinematics of the Pamir salient since the Late Cenozoic. Integrated with the crustal evolution history during the Middle–Late Cenozoic and the deep structure, we proposed a new model to explain the multi-stage kinematics and associated geodynamics of the Pamir salient. During ∼37–24 Ma, the initial Pamir salient moved northward via radial thrusting that rotated the basins on both sides, which was driven by the continuous compression of the Indian slab after the breakoff of its oceanic part. During ∼23–12 Ma, the gravitational collapse of the Central and South Pamir crusts, which was induced by the breakoff of the continental part of the Indian slab, triggered the extension within the Pamir and foreland-ward movement of the upper crust. The upper crustal materials moved in varying directions due to the differential strength of the foreland areas, transforming the crustal kinematics from radial thrusting into a combination of radial thrusting and transfer faulting. Since the coupling of the Indian and Pamir slabs at ∼12–11 Ma, the deformation propagation towards the forelands accelerated, after which the kinematics of the Pamir salient exhibited asymmetric radial thrusting that has been sustained until the present. The asymmetric radial thrusting was likely driven by the compressive stress effect of the lithospheric basal shear generated by the underthrusting of the cratonic Indian lithosphere, which further led to the rollback of the Pamir slab and the consequent migratory extension in the South Pamir.

Currently, the load on railway tracks is increasing due to the increase in freight traffic. Accordingly, more and more serious requirements are being imposed on the reliability of the roadbed, which means that studies of methods for monitoring the integrity of the railway roadbed are relevant. The article provides a mathematical substantiation of the possibility of using seismoelectric and phasemetric methods of geoelectric control of the roadbed of railway tracks in order to identify defects and deformations at an early stage of their occurrence. The methods of laboratory modeling of the natural–technical system “railway track” are considered in order to assess the prospects of using the presented methods. The results of laboratory studies are presented, which have shown their high efficiency in registering a weak useful electrical signal caused by seismoacoustic effects against the background of high-level external industrial and natural interference. In the course of laboratory modeling, it was found that on the amplitude spectra of the output electrical signals of the investigated geological medium in the presence of an elastic harmonic action with a frequency of 70 Hz, the frequency of a harmonic electrical signal with a frequency of 40 Hz is observed. In laboratory modeling, phase images were obtained for the receiving line when simulating the process of sinking the soil base of the railway bed, confirming the presence of a transient process that causes a shift in the initial phase of the signal Δφ = 40° by ~45° (Δφ’ = 85°), which allows detection of the initial stage of failure formation.

In this paper, the authors consider the issue of processing the data of electromagnetic pulses (EMPs) recorded in mine workings and their interpretation. The Sami fault (Russia, the Murmansk region) was chosen as the object of the research. A number of experiments, including measuring the EMP level along the fault and the analysis of the results, were performed by the authors. The paper also presents a previously unconsidered method of transition from geological concepts to electro-technical ones, the aim of which is to identify the dependences of the amplitude of electromagnetic field anomalies on the parameters of active tectonic disturbances. The authors assumed the dependence of the amplitude of anomalies on the geological parameters of the rock mass and the thickness of the tectonic disturbance.

В работе представлены аспекты основных методов геодинамических исследований на территории Азербайджана. Представлена история развития GPS-сети. В результате полученных данных за 2015-2016 гг. было выявлено, что существующее распределение скоростей способствует накоплению напряжений различной величины вдоль Главного Кавказского надвига, что может сказываться на сейсмическом режиме исследуемого региона.

Recent deformation processes taking place in real time are analyzed on the basis of data on fault zones which were collected by long-term detailed geodetic survey studies with application of field methods and satellite monitoring.A new category of recent crustal movements is described and termed as parametrically induced tectonic strain in fault zones. It is shown that in the fault zones located in seismically active and aseismic regions, super intensive displacements of the crust (5 to 7 cm per year, i.e. (5 to 7)·10–5 per year) occur due to very small external impacts of natural or technogenic / industrial origin.The spatial discreteness of anomalous deformation processes is established along the strike of the regional Rechitsky fault in the Pripyat basin. It is concluded that recent anomalous activity of the fault zones needs to be taken into account in defining regional regularities of geodynamic processes on the basis of real-time measurements.The paper presents results of analyses of data collected by long-term (20 to 50 years) geodetic surveys in highly seismically active regions of Kopetdag, Kamchatka and California. It is evidenced by instrumental geodetic measurements of recent vertical and horizontal displacements in fault zones that deformations are ‘paradoxically’ deviating from the inherited movements of the past geological periods.In terms of the recent geodynamics, the ‘paradoxes’ of high and low strain velocities are related to a reliable empirical fact of the presence of extremely high local velocities of deformations in the fault zones (about 10–5 per year and above), which take place at the background of slow regional deformations which velocities are lower by the order of 2 to 3. Very low average annual velocities of horizontal deformation are recorded in the seismic regions of Kopetdag and Kamchatka and in the San Andreas fault zone; they amount to only 3 to 5 amplitudes of the earth tidal deformations per year.A ‘fault-block’ dilemma is stated for the recent geodynamics of faults in view of interpretations of monitoring results. The matter is that either a block is an active element generating anomalous recent deformation and a fault is a ‘passive’ element, or a fault zone itself is a source of anomalous displacements and blocks are passive elements, i.e. host medium. ‘Paradoxes’ of high and low strain velocities are explainable under the concept that the anomalous recent geodynamics is caused by parametric excitation of deformation processes in fault zones in conditions of a quasi-static regime of loading.Based on empirical data, it is revealed that recent deformation processes migrate in fault zones both in space and time. Two types of waves, ‘inter-fault’ and ‘intra-fault’, are described. A phenomenological model of auto-wave deformation processes is proposed; the model is consistent with monitoring data. A definition of ‘pseudo-wave’ is introduced. Arrangements to establish a system for monitoring deformation auto-waves are described.When applied to geological deformation monitoring, new measurement technologies are associated with result identification problems, including ‘ratios of uncertainty’ such as ‘anomaly’s dimensions – density of monitoring stations’ and ‘anomaly’s duration – details of measurements in time’. It is shown that the RSA interferometry method does not provide for an unambiguous determination of ground surface displacement vectors.

Сегодня все больше внимания уделяется сейсмотектонике, так как от решения ее вопроса зависит, в частности, достоверность карт СР (сейсмическое районирование) сейсмоактивных регионов. В данной статье рассматривается сейсмотектоника Азербайджана.

The study was carried out by applying the Hooke’s physical law – to describe the relationship of the horizontal strains and geodynamic stresses of the Earth-crust. Experimental studies were carried out in the territory of the geodynamic polygon of the Ignalina Nuclear Power Plant. New data of geodynamic stress changes that are significantly related with the tectonic structure of the territory were obtained. After the analysis and generalization of results obtained, the change of tectonic stresses in the surroundings of the geodynamic ground of the Ignalina Nuclear Power Plant and its connections with tectonic structure were determined. The conclusion is drawn that Hooke’s law, by describing the relations between horizontal strains of the Earth-crust and geodynamic stresses, may be used practically and applied for estimating the regularities of the geodynamic stress change.

The programme Ansys was applied to model the horizontal movements and the change of tectonic stresses of the Earth crust according to the data of geodetic measuring by the finite element method. Experimental studies were carried out in the territory of the geodynamic polygon of the Ignalina Nuclear Power Plant. The detailed results of parameters of horizontal deformations have been obtained; the new indices of tectonic stress increases - the most important stress increases were calculated and their directions established. On the basis of the study results and their analysis, the conclusion was drawn that the programme Ansys may be applied to model horizontal movements of the Earth crust. The merit of application of this programme, in comparison with usual widely-applied methods of geodetic researches, is not only that it is possible to detail the dispersion of the Earth crust deformations, but also to obtain a new information about the change of tectonic stresses. Article in Lithuanian Žemės plutos horizontaliųjų judesių tyrimas Ansys programa Santrauka. Žemės plutos horizontaliesiems judesiams ir tektoninių įtampų kaitai modeliuoti pagal geodezinių matavimų duomenis baigtinių elementų metodu taikyta Ansys programa. Eksperimentiniai tyrimai atlikti Ignalinos atominės elektrinės geodinaminio poligono teritorijoje. Gauti detalūs horizontaliųjų deformacijų parametrai bei apskaičiuoti nauji tektoninių įtampų prieaugių rodikliai – svarbiausieji įtempimų prieaugiai, nustatytos jų kryptys. Remiantis tyrimo rezultatais bei jų analizės duomenimis, daroma išvada, kad horizontaliesiems Žemės plutos judesiams modeliuoti gali būti taikoma Ansys programa. Šios programos taikymo privalumas, palyginti su įprastiniais plačiai taikomais geodezinių tyrimų būdais, yra ne tik tai, kad galima detalizuoti Žemės plutos deformacijų sklaidą, bet ir gauti naujos informacijos apie tektoninių įtampų kaitą. Raktažodžiai: baigtinių elementų metodas, GPS, geodinaminiai procesai, tektoninės įtampos, Žemės plutos deformacijos.

The study was performed with intent to apply the inverse Hook’ law – to describe connections between horizontal deformations of the Earth-crust and geodynamic stresses; tensor methods of stress estimation were based theoretically and experimental calculations were carried out in the territory of the Ignalina Nuclear Power Plant region. New data of the study of geodynamic stress change that are significantly related to a tectonic structure of the territory were obtained. Having analysed and generalised the results of calculation according to geodetic surveys, a tectonic activity in the surroundings of the graben Drūkšiai was established. The conclusion is drawn that the inverse Hook’ law, by describing the connections between horizontal movements of the Earth-crust and geodynamic stresses, may be used practically and applied for estimating the regularities of the geodynamic stress change. Article in Lithuanian Geodinaminių žemės plutos įtampų pokyčiai Ignalinos atominės elektrinės regione Santrauka. Tyrimas atliktas siekiant pritaikyti atvirkštinį Huko fizinį dėsnį horizontaliųjų Žemės plutos deformacijų bei geodinaminių įtampų s ąsajoms aprašyti, teoriškai pagrįsta tenzorinė įtampų įvertinimo metodika bei atlikti eksperimentiniai žemės plutos įtampų Ignalinos atominės elektrinės regiono teritorijoje skaičiavimai. Gauti nauji geodinaminių įtampų pokyčių duomenys, kurie akivaizdžiai yra susiję su teritorijos tektonine sandara. Išanalizavus skaičiavimo pagal geodezinių matavimų duomenis rezultatus ir apibendrinus, nustatytas tektoninis aktyvumas Drūkšių grabeno aplinkoje. Daroma išvada, kad atvirkštinis Huko dėsnis, nusakant horizontaliųjų Žemės plutos judesių bei geodinaminių įtampų sąsajas, gali būti taikomas praktiškai bei įvertinant geodinaminių įtampų pokyčių dėsningumus. Raktažodžiai: GPS, geodinaminiai procesai, tektoninės įtampos, Žemės plutos deformacijos.