A review of the theory of global warming was carried out, the possible reaction of permafrost to climate change was considered, the complex nature of the relationship between soil temperature and air temperature was shown, the possible scale of permafrost degradation in Russia and the likely economic damage were described. Examples of deformations of buildings and engineering structures are given. It is proposed by authors a variant of complex permafrost monitoring system including forecast and management as one of the measures to adapt to climatic changes.

We tested the coincidence of key poles, paleomagnetic poles, recalculated from the secondary different- age components of NRM and the reference Phanerozoic poles of the East European and Laurentia cratons. The main periods of such coincidences are highlighted. Based on the correlation of angular distances between pairs of the same-age poles of the East European and Superior cratons, three times poles (1.59–1.45 Ga, 580–550 Ma and 250–200 Ma) was found as a result of remagnetization during distroy of the supercontinent Pangaea. It is shown that the coincidence of the Precambrian pole with the Phanerozoic part of the APWP is not always a consequence of remagnetization, but may be due to the “repeatability” of the position of the same craton at the same position of the Globe as part of various Precambrian supercontinents. The potential “repeatability” of the position of the same tectonic block in the same area of the globe at different times in geologic history was carried out.. The results show that over a period of 2.5 Ga, the same block can be found more than twice in the same area of the Globe, which can explain the coincidence of poles of different ages. Distingsions between time of existences of NENA megacontinent and the Precambrian supercontinents Rodinia, Nuna/Columbia and Kenorland may be associated with introversal and extroversal mechanisms of supercontinent formation, respectively.

Detailed paleomagnetic studies of rocks of the Kivakka layared intrusion and dolerite dikes have been carried out. Four metachronous components of NRM have been identified. The high-temperature/high-coercivity component isolated in the rocks of the Kivakka layaered intrusion was formed during the crystallization of the massif 2.45 Ga. The three mechatronic components of NRM were formed as a result of the action of hydrothermal fluids at different stages of the evolution of the Kivakka layered intrusive at ca 2.05 Ga, ca 1.98 Ga and 1.88 Ga. Comparison of these components with different ages one for the Kivakka and Burakovsky layered intrusions, as well as Paleoproterozoic mafic dykes of the Paanayar structure showed that the slope of the Kivakka layared intrusive most likely occurred during the formation of the Lapland-Kola orogen between 2.05 and 1.98 Ga, and not during the introduction, as previously assumed.
Thermodynamic modeling of the formation of hydrothermal mineral parageneses for rocks of the Kivakka layered intrusive showed that in the case of hydrothermal action on olivinite, serpentine+magnetite paragenesis occurs in all cases with a small admixture of chlorite, actinolite. It is established that the formation of secondary magnetite is a characteristic of sulfate-free sodium chloride. Increasing the concentration of sodium chloride increases the amount of magnetite, which corresponds to the results of the experiments.

Our structural-geomorphological and morphometric studies have shown that seismically active areas of Sakhalin Island are distinguished by positive anomalies of 9 morphometric parameters of the relief, where their values exceed the median. These parameters include the difference between the hypsometric surface and the 3rd order base surface; differences between the 1st and 2nd orders, 2nd and 3rd orders base surfaces; depth of vertical dissection; standard deviation of slope exposure; density of “weak” zones; height asymmetry, standard deviation of the Gaussian curvature of the relief, taken by the module and standard deviation of heights. It is shown that seismically active areas can also be contoured by the values of the 7 mentioned parameters (excluding the last two mentioned), exceeding the 3rd quartile. The density of “weak” zones is the most informative: 45% of all earthquake epicenters and 71% of earthquake epicenters with a surface waves magnitude of ≥ 5.5 fall into small areas (25% of the island’s area) where the density of “weak” zones is ≥ 36 km–1. Thus, the example of a well-studied seismotectonic territory shows the possibilities of identifying seismically active areas based on a set of geomorphological characteristics. This result may be in demand when assessing the seismic hazard of areas with mid-mountain relief, where detailed seismological studies have not been conducted previously.

The article describes the first findings of glendonites (pseudomorph after calcium carbonate hexahydrate ikaite that crystallize at near-freezing temperatures) from the Bazhenovo Formation (West Siberia, Upper Jurassic — Lower Cretaceous). Glendonites originate from the depressed structures of the central part of the Froly megadepression and the deepest areas of the West Siberian paleobasin. Glendonite findings have received a reliable stratigraphic reference and come from the interval of the Ryazanian regional stage. Based on the stable isotopes composition, we propose ikaite crystallized and transformed during organoclastic sulfate-reduction in the bottom sediments. Ikaite crystallization could have been caused by the penetration of bottom cold currents from the Paleoarctic basin due to sea level fluctuations during the Ryazanian stage.

Chronolithostratigraphic characteristics of Meso-Cenozoic sediments of the Sea of Okhotsk are given, their formation analysis is carried out and paleoclimatic, paleohalinometric and paleobatimetric reconstructions for Meso-Cenozoic sediments of the Chukchi Sea are carried out on the basis of a set of data.

An astrochronological (cyclostratigraphic) binding of the lithological and geochemical characteristics of the Neogene-Quaternary sediments of the sections to the Milankovich cycles (eccentricity, inclination of the ecliptic, precession) was carried out, an analysis of the relationship between the established variations of climate and paleotemperature with the moments of coincidence of different Milankovich cycles was given, a possible limit of the method of high-precision planetary correlation was determined. Correlation markers for the method of high-precision planetary correlation of precipitation of the Quaternary system have been determined. Astroclimatic markers (benchmarks) for dissection and correlation of sections can be considered traces in the sedimentary sequence of phases of combination of different Milankovich cycles, generating climate changes, as well as impact events correlating with phases of combination of different Milankovich cycles. When analyzing the chronological distribution of impact structures, it was found that most of them coincide in time of their formation with the phases of combining different cycles of the Earth’s eccentricity or with the moments of combining different Milankovich cycles — precession, obliquity of the ecliptic and eccentricity, thereby marking these milestones in geological history. Gabdullin R.R. proposed a model explaining the correlation between the phases of combining different Milankovich cycles and episodes of impact events. The materials of the Museum of Earth Science of Moscow University were used in the study.

The results of a comprehensive study of the deposits of the Turonian and Coniacian on the territory of the Eastern Perithetys are presented. The issues of changing paleoenvironments and assemblages of foraminifera at the boundaries of the stages are considered. It is shown that the oceanic anoxic event OAE 2 at the boundary of the Cenomanian and Turonian was quite long-term and took place in several phases. The Turonian-Coniacian interval was characterized by the existence of a relatively deep-sea open-sea epicontinental basin of the Tethys Ocean, where carbonate sedimentation, mainly of the hemipelagic type, took place.

The Yuryuzano-Sylvenskaya depression is part of the Uralian foredeep. It is filled with flysch-molasse complexes in the interval from the Moscovian stage of the Middle Carboniferous to the Artinskian stage of the Lower Permian. Nine samples were taken from different levels of the section to isolate and date detrital zircons. Of particular interest is the distribution of Precambrian ages in these zircons. From bottom to top, the amount of Precambrian zircons generally decreases from 97% to 4%. At the same time, the age distribution spectra of these zircons coincide throughout the section, which suggests a single source for them. In addition, these spectra are practically indistinguishable from the spectrum of zircons of the Asha series of the Vendian Bashkir megazone, which, apparently, is the source of Precambrian zircons of the Upper Paleozoic suites of the Yuryuzan-Sylvenskaya depression. It was a permanent element of the provenance area for the Upper Paleozoic suites of the Yuryuzano-Sylvenskaya depression. The Riphean rift complexes of the Bashkir megazone and the Archean-Early Proterozoic complexes of the Taratash ledge were not included in the provenance area.

2D and 3D modeling of sedimentation of Cenozoic clinoform complexes was done. There are two clinoform complexes in the North Chukchi basin, the lower — Paleocene-Eocene and the upper — Oligocene. The source of sedimentary material for clinoforms are the orogens of Alaska and Chukotka. Two-dimensional modeling of the upper clinoform complex was performed, and sea level fluctuations necessary for the formation of clinoforms were determined. Based on the results of three-dimensional sedimentation modeling, possible sources of demolition and quantitative characteristics of the input of sedimentary material were determined. The rivers that provided the sediment supply in the Oligocene are comparable to the modern Kolyma and Northern Dvina.

The article provides a comprehensive overview of the potential of energy resources of African countries based on geological prerequisites in the structure of sedimentary basins of the region. On the basis of numerous sources, the categorization of countries by the amount of hydrocarbon production, as well as by the size of resource potential of countries, has been carried out. For the largest countries in terms of production and reserves, a comparison is given with the main oil and gas basins, within which the producing fields are located and the main hydrocarbon reserves have been explored. In the context of the transition to renewable energy sources, the article examines African countries with high geothermal potential, such as Kenya, Ethiopia, Uganda, Tanzania, Zambia, capable of meeting the demand for electricity and heat. Various directions of application of geothermal heat depending on the temperature of the coolant are considered. The article provides examples of successful application of modern digital technologies to identify promising sites for further research and operation.

The average contents and paired correlation coefficients of elements for the geochemical background of sedimentary rocks in the central part of the Nakyn kimberlite field, which contains the Mayskoye and other diamond deposits, and in the area of the deposit near the kimberlites are calculated. Elements of kimberlites, carbonatites and basites were selected for analysis: Cr, Ni, Co, Ba, Sr, Zr, Zn, V and Sc. High positive correlation coefficients between the specified elements have been established for background contents. At the same time, in the near-kimberlite space, while maintaining the average background contents, significant decreases in correlation were found up to its absence between elements of different groups. Differences in the average contents of elements in the compression and stretching sectors are revealed. A mechanism for the redistribution of elements in high-temperature (100–600 °C) fluids accompanying the explosive formation of kimberlites is proposed. The established violation of correlations of background element contents in the sedimentary rocks containing kimberlites may become a new search feature of hidden diamond deposits.

The analysis of the dynamics of changes in the landscape and soils near the Mikhailovsky mining and processing plant using satellite image processing is carried out. The possibility of using spectral indices for a semi-quantitative assessment of the iron content in soils and tailings of ferruginous quartzite beneficiation is analyzed.

A representative collection of diamonds from the Gusinyi Ruchey (Anabar, Yakutia) placer has been studied by morphological analysis, infrared spectroscopy and electron paramagnetic resonance methods. Typomorphic features of Gusinyi Ruchey diamonds are the relatively high content of crystals of V and VII varieties according to the classification of Y.L. Orlov, even for Anabar placers, with a decrease in the proportion of curved dodecahedroids. The latter correlates with a decrease in the prevalence of sculptures and hatching on the surface of crystals. Also, the characteristic features include an increased content of diamonds with the presence of gray tones in the color and with graphite inclusions. The proportion of colorless crystals is only 5.9%. More than 11% of crystals are able to luminesce when excited by ultraviolet radiation at a wavelength of 254 nm. The diamonds of the Gusinyi Ruchey placer partially enrich the “Nizhniy “ section of the Ebelakh placer, this increases its diamond content, but not the quality of the rough diamonds.

The paper presents the results of organic matter (OM) kinetic analysis of 41 the Bazhenov Formation rock samples from one well. The kerogen maturity of all the samples is low (early oil window). According to the results the kinetic characteristics of kerogen, such as activation energy of bonds destruction, frequency factor, generation beginning and end temperature, might vary significantly within one section. The range of temperature variation required to transform 50% of OM in the investigated samples is up to 27 °C. The difference in modeling with different kinetic spectra shows that representing the entire section of the Bazhenov Formation as a single homogeneous rock with same OM is incorrect and will significantly affect the accuracy of the resulting basin models.

In the article, based on geohydrological modeling of the groundwater recharge and resources, an analysis of their current and predicted climate changes was carried out using the example of the Vaimuga river basin, Arkhangelsk region. It was found, that landscape differences in climatic variability of groundwater recharge are significant even over the area of small river basins, and the scale and direction of its predicted changes based on global climate models differ significantly. At the same time, predicted climate changes do not have a significant impact on the groundwater exploitation, but are manifested in the degree of its impact on river flow.

Thermochemical sulfate reduction (TSR) is one of the mechanisms responsible for the generation of hydrogen sulfide in a reservoir. Recently, novel hydrogeochemical modeling approaches are developed to unravel TSR in hydrocarbon reservoirs. These modeling were developed in order to comprehend the basic hydrogeochemical mechanisms for H2S production and its controlling factors. In this paper, the modeling of the TSR process in Permian-Lower Triassic deposits was carried out using the example of the Shanul gas field in southwestern Iran. The one-dimensional diffusive mass transport model used in this study (Phreeqc) is based on equilibrium reactions for gas–water–rock interactions and kinetic reactions for sulfate reduction and methanogenesis. The simulation results show that the intensity of the TSR reaction and the volume of driven H₂S are influenced to a large extent by three factors: the mineral composition of the host reservoir rock, the pressure drop of the reservoir, and the pH of the formation water. The results highlight that, the mineral composition of the host rocks alters the intensity of TSR process. The presence of iron containing minerals may significantly inhibit the H₂S production. Modeling results show that the presence of 5% iron-containing minerals could completely remove hydrogen sulfide from the system within 20 years. Moreover, it has been observed that the change in reservoir pressure after production or injection also significantly affects the content of hydrogen sulfide in the reservoir. A pressure drop up to fifty percent (from 600 to 300 atm) of the initial reservoir pressure increases the H2S content by more than ten times (from 4×10^–4 to 4×10^–3 mol/kg (H₂O). In addition, it has been shown that changing the pH of an aqueous solution significantly changes the rate of TSR reaction. According to the simulation results a 20% decrease in water pH (From 6.5 to 5.7) will lead to an increase in H₂S concentration from 8×10^–4 to 16×10–4 mol/kg (H₂O).

The fluorine content in the waters of four aquifers of the Essentuki mineral water field (Danish-Zelandian, Cenomanian-Maastrichtian, Aptian-Lower Albian, and Tithonian-Valanginian) was determined. The possibility of regulating the fluorine content in extracted mineral water by changing the intensity of well operation was shown.

As a result of the analysis of data from literary sources, the average values of the reaction rate constant for the dissolution of gypsum in water (k_av = 1,48 × 10^–5 mmol/(cm²s), 25 °C) and activation energy (E_av ^I = 39 kJ/mol), characteristic of kinetic and diffusion-kinetic control conditions, were determined.. The calculated temperature dependence obeys the Arrhenius equation in the range 0–40 °C (logk_av = 1,95–2021/T, K). An increase in solution temperature (T > 40 °C) causes diffusion inhibition of heterogeneous chemical reactions of gypsum dissolution. It is assumed that at T ≈ 40–42 °C the boundary between the macrokinetic regions of the process of dissolution of gypsum in water corresponds to the zone of temperature transition between the equilibrium state of gypsum and anhydrite (CaSO₄ · 2H₂O^s-CaSO₄ s-H₂O; P = 0,1 MPa). It is proposed that a similar transition in electrolyte solutions should also be determined taking into account the diffusion resistance of the rate of chemical interactions on the reaction surface of gypsum with increasing solution temperature.

A characteristic simplified resistivity model of the earth’s crust has been compiled, containing a three-dimensional conductive sedimentary depression in a resistive basement. Two variants of the model are considered: with a uniform near-surface part and with multiple local near-surface inhomogeneities. Using three-dimensional modeling, synthetic magnetotelluric sounding (MTS) data were calculated using a system of profiles. In the data for the second variant of the model, a widespread effect of near-surface distortions is observed, leading to a static shift in the amplitude MTS curves, but not affecting the phase curves. We applied methods for separating local and regional effects in MT data, based on the corresponding decomposition of the impedance tensor. It is shown that, under the conditions of the applicability of this decomposition, the Bahr’s and phase tensor methods make it possible to confidently determine the principal directions (azimuths) associated with regional structures (with a sedimentary depression) and not distorted by local effects (of near-surface inhomogeneities). The effectiveness of using maps of principal directions, polar diagrams of the phase of impedance tensor component and of the phase tensor components, as well as phase tensor ellipses for characterizing regional resistivity structures is demonstrated.