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—In recent years, the supra-long Yamal tree-ring chronology has been significantly extended and became much more reliable. This article characterizes the sample wood used to build the longest absolutely dated Siberian Larch tree-ring chronology of the Subarctic area, i.e. from 6748 BC to 2019 AD, for a total continuous period of 8768 years. The ecological value of the temporal and spatial distribution of the dated trees are presented, and their potential use for application in various field of natural sciences and humanities are discussed.

In the northern part of the Siberian Platform, east of the Anabar Shield, several massifs of alkaline rocks with carbonatites identified (Tomtor, Bogdo, Promezhutochnyi) and projected according to geophysical data (Bualkalakh, Chuempe, Uele) form a large alkaline–carbonatite province. The first data on the composition of alkaline rocks of the Bogdo massif indicate that the latter belong to a group of feldspathoid rocks of basic composition: rischorrites, biotite–aegirine liebenerite syenites, carbonatized pseudo-leucite nepheline syenites with symplectites, and nepheline–feldspar aggregates. Sphene grains were extracted from various rocks of the Bogdo massif, and their U‒Pb age was determined using the SHRIMP-II secondary-ion microprobe. The calculated U‒Pb age is 394.4 ± 3.2 Ma, which is similar to the age of the Tomtor massif and the age of the rocks of the Kola alkaline province. One of the reasons for the manifestation of alkaline plume magmatism on this territory may be the effect of the peripheral zone of the African Large Low Shear Velocity Province (“Tuzo”) on the Baltic area and Siberia during the Devonian age.

The Eastern European steppe and forest-steppe is a key region for understanding the emergence of pottery in Europe. The vast region encompasses the basins of two major waterways, the Don and the Volga rivers, and was occupied by hunter-gatherer-fisher communities attracted to highly productive forest/aquatic ecotones. The precise dates for the inception of pottery production in this region and the function of pottery is unknown, but such information is vital for charting the pan-Eurasian dispersal of pottery technology and whether there were common motivations for its adoption. To investigate, we conducted AMS dating, including a re-evaluation of legacy radiocarbon dates together with organic residue analysis and microscopy. The dating programme was able to clarify the sequence and show that hunter-gatherer pottery production was unlikely in this region before the 6th millennium BC. Regarding use, stable isotope and molecular analysis of 160 pottery samples from 35 sites across the region shows that terrestrial animal carcass fats were preferentially processed in pots at Middle Volga sites whereas aquatic resources dominate the residues in pottery from the Middle and Upper Don basin. This is supported by fragments of fish, legumes and grasses in the available charred deposits adhering to the inside of pottery from the Don basin. Since the sites from both river basins had similar environmental settings and were broadly contemporaneous, it is posited that pottery use was under strong cultural control, recognisable as separate sub-regional culinary traditions. The ‘aquatic hypothesis’, previously suggested to explain the emergence of Eurasian pottery, cannot be substantiated in this context.

We provide and test a method to obtain significant improvement of available Chandrayaan-1 M3 data. The advance is achieved using the Gaussian λ-convolution of spectra and Fourier filtration of images. The main result is imagery of the reflectance across different wavelengths as well as parameters of 1 µm and 2 µm absorption bands with unprecedented quality. This approach can be particularly useful for further investigations using M3 data, since it produces improved imagery of various lunar surface characteristics. We studied a region comprising a portion of the Aristarchus Plateau, Montes Agricola, and a small part of the mare surface in Ocean Procellarum to the north of Montes Agricola. We found that the lava flows in the area between the Aristarchus Plateau and Montes Agricola have a chemical/mineral composition different in comparison with mare areas to the northwest of the ridge Montes Agricola. We also identified distinct spectral properties of morphologically young craters located on the plateau and mare surface. A correlation diagram for positions of the minima of the 1 µm and 2 µm bands allows a cluster analysis of the region, and we map areas associated with a cluster corresponding to pyroclastic glasses. Relationships between geologic and spectral parameter maps were established.

The mechanism of the generation of the geomagnetic field disturbance accompanying tsunami wave propagation is considered. Electric currents in the marine environment and the ionosphere are the source of the disturbance. The current in the marine environment arises as a result of its motion in the tsunami wave, while the current in the ionosphere occurs due to the occurrence of an acoustic-gravity wave (AGW) propagating from the atmosphere on the ionosphere. The source of the AGW is the vertical displacement of the surface of the marine environment during tsunami-wave propagation in it. Although the ionospheric conductance is significantly smaller than the conductivity of the marine environment, the current value in it may considerably exceed the current value in the marine environment due to the exponential growth in the AGW amplitude during AGW upward propagation. The spatial distribution of a disturbance in the induction of the magnetic field of electric currents flowing in the marine environment and in the ionosphere is obtained with allowance for their mutual inductance. It is shown that the generation of the ionospheric electric current considerably changes the characteristics of the geomagnetic field disturbance induced by a tsunami wave. Calculations have demonstrated the possibility of space monitoring of tsunami waves with the use of satellites to record disturbances of the geomagnetic field.

Forecasting of economic indicators with time series using one or another method or another but the only method leads to the situation that all the information contained in other forecasting methods is usually discarded. The information that is ignored may contain information that allows other features of the economic process to be assessed. Combining forecasts makes possible to take into account almost all the information contained in particular forecasts. In the article, we present the analysis of the application of the method of regression analysis, in particular, ridge regression for finding the weighting coefficients of the particular forecasts in the combined forecast. We compared the accuracy of prediction based on the ridge regression with other methods of combining predictions. The purpose of our research work was an analysis of the most common methods of combining forecasts — various modifications of Granger-Ramanathan methods and comparison with a new approach of combining forecasts based on the ridge regression for its use in practice. We used statistical methods of time series forecasting (the method of harmonic weights, adaptive exponential smoothing using a tracking signal, the method of simple exponential smoothing and the Box-Jenkins model), the method of constructing combined forecasts, as well as methods of regression analysis. As a result, we built the combined forecasts based on annual data for the period from 1950 to 2015 on the production in Russia of some products: steel, metallurgical coke, pulp, plywood, cement. We used the methods of Granger-Ramanathan (without restrictions and with restrictions on the sum of coefficients in partial predictions) and also the ∆-coefficients obtained by the ridge regression method. The forecasts constructed using the Granger-Ramanathan methods give the highest accuracy of the combined forecast. The method based on the ridge regression is less accurate, but better than the separate predictions. At the same time, the proposed method of calculating the weight coefficients on the basis of the ridge regression has a well- developed scheme of calculation and eliminates the negative weight coefficients in the combined forecast.

Seismoelectric effect is studied in the framework of classical Lamb’s problem with impulse or time- variable mechanical action on an elastic porous half-space. Radiation of elastic waves gives rise to pressure variation of groundwater fluid contained in pores and cracks. This causes the generation of telluric electric fields and currents due to the seismoelectric effect. A diffusion type equation is applied to describe the variations of the pore pressure and telluric electric field. Particular emphasis has been placed on the properties of seismoelectric signals caused by Rayleigh wave propagation since this wave has maximal amplitude at a considerable distance from the seismic source. For practical purposes and geophysical application, the co-seismic phenomena related to seismoelectric effect are examined in more detail.

The problem of comparison of the composition of crystalline rocks with the composition of the constituent minerals of these rocks is considered. It is proposed to present the composition of rocks and the compositions of the constituent minerals in the form of a triangle on the plane. The experience of presentation of compositions in phase diagrams was taken as a basis for the construction. Analysis of the crystallochemical characteristics of clinopyroxenes and garnets has shown that three parameters are enough for depicting the compositions of these and other minerals. For this purpose, similar composition components of rocks and their minerals are summarized in molecular proportions and are plotted on the triangle DO-1/2(R2O3)-XO2, where DO = (MgO + CaO + FeO + MnO + NiO + …) + 1/4(Na2O + Al2O3) + 1/4(K2O + Al2O3), 1/2(R2O3) = 1/2(Al2O3 + Fe2O3 + Cr2O3 + …) - (1/4(Na2O + Al2O3) + 1/4(K2O + Al2O3)), and XO2 = SiO2 + TiO2. The compositions of minerals are expressed as the sums of their components: Ol = Fo + Fa + Lar + Neph + …, Px = Di + En + Wol + Ged + Gip + Jd + Eg + …, Ga = Pyr + Gross + Alm + Spe + Ski + Knr + Mj + …, etc. A step-by-step calculation algorithm is proposed, which permits evaluation of the contents of bi- and trivalent iron during probe microanalyses of garnets and pyroxenes. Comparison of the compositions of deep-seated rocks and their minerals shows their good consistency. The proposed schematic projection permits a visual comparison of the compositions of rocks with low contents of carbonates and water, from ultrabasic (e.g., dunites) to acid (e.g., granites) ones.

We analyze theoretically two possible sources of co-seismic electromagnetic response to the propagation of various types of seismic waves caused either by the electrokinetic phenomena or geomagnetic inductive effect. The differences between these two generation mechanisms have been examined for different types of seismic waves (P, S, and Rayleigh-Love). Theoretical relationships describing the dependence of the co-seismic signal amplitude, polarization and apparent impedance on the earthquake seismic moment and magnitude have been derived as a function of distance. We indicate an observational possibility to discriminate seismo-electrokinetic and seismo-magnetic effects and to estimate their contribution into a recorded co-seismic electromagnetic signal. Magnitudes and polarization of these signals are shown to depend strongly on the type of seismic wave and local crust parameters, such as streaming potential coupling coefficient, conductivity, inhomogeneity, etc. Co-seismic electromagnetic signals, though not directly applied for earthquake prediction, contain a useful information on local crustal phenomena, and can be used to identify “sensitive” zones perspective for the monitoring of precursory electromagnetic disturbances.

The article is devoted to the publication of security excavation materials of three burial mounds from the Peschanokop district of Rostov-on-Don region. Each burial mound contained only one looted tomb. The tomb in the shaft-in-chamber from the mound Bogoroditsky IV with featureless inventory and western orientation belongs to sarmatian culture of the 3rd – 1st century BC. Infill of the tomb contained parts of two unevenaged men’s skulls, handmade pottery parts and a gray-clay wheeled bowl. The pottery has North-Caucasian origins, but it is not exactly dated. The tomb from mound 6 of the burial mound Peschanokop belongs to the undermound Sarmatian catacombs dated by Roman period. A censer and a gray-clay wheeled bowl have meotian analogies, dated by the 2nd century AD. The dating of the tomb is confirmed by the golden pendant-medallions incrusted by the red carnelian insertion which belonged to the Greek-Roman polychrome style. The analogies are found in the Volga-Don and Kuban regions. The tomb from mound 6 of the burial mound Peschanokop belongs to the Bulgarian variant of Saltov-Mayaki culture and is dated by the 8th – 9th centuries AD. The main features of the mound include the western orientation of the man’s skeleton, horse remains in particular and parts of the sacrificial sheep, remains of the coffin and mat. There was also a shaft-in-chamber near the feet of deceased in the end wall – the feature of the proto-Bulgarian tombs. The ways of the mound’s looting are also various. A tomb from the burial mound Bogoroditsky IV was destructed with the triangulation station mark. Early medieval mound 7 of the burial mound Peschanokop was looted in ancient times with the excavated vertical shaft in the center, under the tomb. The Sarmatian catacomb of mound 7 was looted by the knowledgeable contemporary looters with only enrichment motivation. They got exactly into the shaft of the catacomb and pull out the bones and the artefacts from the burial chamber through the inlet. Although it might be a tomb desecration by the unfriendly families’ members.

We investigate a southern portion of Mare Vaporum using Chandrayaan-1 M3 images for which we suppress striped noise. Additional data processing allows us to analyze such spectral parameters as the depths and positions of the absorption bands near 1 and 2 μm. Mineral types were mapped using the cluster analysis of Adams diagram for pyroxenes. We inspected, in particular, the areas of pyroclastic deposits around the crater Hyginus and small areas in the crater which have the 2 μm band shifted to longer wavelengths. We examined the areas with phase-ratio analysis of LROC NAC images: the areas associated with clinopyroxenes are distinguished both in albedo and phase-ratio (56°/23°) images, perhaps, having higher roughness than surrounding surface; Whereas the areas associated with pyroclastic glasses does not seen neither in albedo nor phase-ratio images.

In-flight measurements are developing directions of aircraft testing. The practical implementation of these tests allows accelerating the development of new types of aircraft, the in-flight tests of serial samples, and their commissioning. Carrying out such tests is associated with high cost. In this paper the creation of a flight laboratory based on an unmanned vehicle is proposed. This will significantly reduce the cost of testing but in-flight conditions will be close to real tests. A system for recording experimental images during in-flight test was developed for conducting studies of deformations of aerodynamic surfaces. In this paper, the system based on single board computer is described; its main functions and features are considered. The results of laboratory tests of the developed system on a model of a deformable wing are presented.

We examine the factors that are responsible for the formation of the beaded structure of channels in the permafrost zone. It is found that formation of beaded channels in the permafrost zone is possible only in the case of small gradients and water flow rates. The existence of such channels in the permafrost zone is unstable; hence, there is little likelihood that they have persisted in a relict form to date

We examine the transformation of a gentle segmental to a meander loop with the result that the city, founded in the 17th century, found itself on the caving bank. Comparison of cartographic materials from different times showed the occurrence of secondary bends on elongated rectilinear wings. Not only did such an evolution of the meanders lead to the caving of the terraced urban bank, but also it involved a likely emergency situation on the underwater crossing of the pipeline, and on other engineering facilities. We ascertained the causes of the ongoing channel deformations; modeling data were used in developing recommendations on meander straightening in order to divert the river away from the city.

The elaboration of theoretical models, even oversimplified, capable to estimate an expected electromagnetic effect during earthquake preparation process is not less important than the advancement of observational technique to detect seismic-related electromagnetic emission. Here possible mechanisms of ULF electromagnetic noise associated with seismic or volcanic activity are discussed. The electrokinetic (EK) and magnetohydrodynamic (MHD) effects due to an irregular flow of conducting rock fluid or magma flow are being revised. The conventional theory of EK effect in a water-saturated rocks has been advanced by consideration of elliptic-shaped channels. A contribution of both mechanisms to observed ULF signal on the ground is shown to be dependent on the pore channel size/rock permeability. Estimates of magnetic and telluric perturbations caused by magma motion along a volcano throat indicate on the important role of the surrounding rock conductivity. These estimates have proven that the mechanisms under consideration are able to generate ULF electromagnetic emission which could be detected by modern magnetometers under favorable conditions.

The Al-rich region of the CaO-MgO-Al2O3-SiO2 system was experimentally studied at pressures of 1.0–2.8 GPa and temperatures of 1300–1535°C. The slopes of the lines of the monovariant reactions An + Sp = Cpx + Cor + (Ga) and L = Cpx + Ga + Cor + Sp and the compositions of the phases involved in these reactions are determined. The results are utilized in the topological analysis of the aluminous region of the CaO-MgO-Al2O3-SiO2 system. On this basis, the principal structure of the phase diagram is analyzed, and a phase diagram is constructed for the junction region of the quaternary system and the CaO-Al2O3-SiO2 ternary system. A continuous series of the monovariant eutectic: L = Cpx + Opx + Fo + An, L = Cpx + Opx + An + Sp, L = Cpx + (Ga) + An + Sp, L = Cpx + Cor + (Ga) + An, L = An + Ga + Cpx + Ky and L = Ga + Cpx + Ky + Qz is examined within the pressure range from atmospheric to 3.0 GPa and higher. Analogous “telescoped” eutectic series are of fundamental character for interpreting the evolution of magmatic melts. A physicochemical model is suggested for the evolution of magmatic melts that produce rocks of the calc-alkaline series, with this model underlain by the fact that a change in the composition of magmatic melt at a pressure decrease should correspond to the minimum melting temperatures, i.e., to melts in the fundamental series of eutectic reactions. The comparison of our physicochemical model and rocks of the calc-alkaline series shows that the compositions of rocks of the calc-alkaline series are close to the compositions determined for the eutectic equilibria, and the mineralogical composition of xenoliths and megacrysts in volcanic and dike varieties of the rocks are similar to the subsolidus phases of the established fundamental eutectic system.

Transient luminous events (TLEs) occasionally observed above a strong thunderstorm system have been the subject of a great deal of research during recent years. The main goal of this review is to introduce readers to recent theories of electrodynamics processes associated with TLEs. We examine the simplest versions of these theories in order to make their physics as transparent as possible. The study is begun with the conventional mechanism for air breakdown at stratospheric and mesospheric altitudes. An electron impact ionization and dissociative attachment to neutrals are discussed. A streamer size and mobility of electrons as a function of altitude in the atmosphere are estimated on the basis of similarity law. An alternative mechanism of air breakdown, runaway electron mechanism, is discussed. In this section we focus on a runaway breakdown field, characteristic length to increase avalanche of runaway electrons and on the role played by fast seed electrons in generation of the runaway breakdown. An effect of thunderclouds charge distribution on initiation of blue jets and gigantic jets is examined. A model in which the blue jet is treated as upward-propagating positive leader with a streamer zone/corona on the top is discussed. Sprite models based on streamer-like mechanism of air breakdown in the presence of atmospheric conductivity are reviewed. To analyze conditions for sprite generation, thunderstorm electric field arising just after positive cloud-to-ground stroke is compared with the thresholds for propagation of positively/negatively charged streamers and with runway breakdown. Our own estimate of tendril's length at the bottom of sprite is obtained to demonstrate that the runaway breakdown can trigger the streamer formation. In conclusion we discuss physical mechanisms of VLF (very low frequency) and ELF (extremely low frequency) phenomena associated with sprites.

An experimental study of serpentine decomposition at high pressure (4.5 GPa) was carried out to elucidate if water can be preserved in the system in the form other than structural admixtures in minerals. This problem is of interest because it is water that plays a leading role in the melting in a subducted slab and a mantle wedge. To estimate the possible content of an aqueous fluid in deep-seated rocks, a BARS pressless split-sphere apparatus was used in complex with thermobarogeochemistry and gas chromatography. It has been established that the serpentine decomposition is accompanied by the release of water, which concentrates in inclusions in the produced minerals (olivine and orthopyroxene) and their interstices. Chromatographic analysis with a stepwise heating of samples showed that most of the released water is localized in the interstices, and the rest is conserved in fluid inclusions in the minerals. The produced solid phases conserve 0.13 to 2.43 wt.% fluids as inclusions, with water amounting to 0.1–2.06 wt.%. The content of inclusions determined by microscopic examination falls in this region. Since the mobility of the fluid conserved as inclusions in the olivine and orthopyroxene is significantly lower than that in the interstices, this fluid might be better preserved in olivine-containing rocks subsided to depth.

To elaborate physicochemical models for the origin of crystalline rocks, experimental studies of the field of high-alumina assemblages of the system CaO–MgO–Al2O3–SiO2 were carried out at 10–30 kbar and 1250–1535 °C. We have determined the phase relations between the melt (L) and An, Sp, Cpx, Cor, and Ga, the slope of the rays of the monovariant reactions An + Sp = Cpx + Cor + (Ga) and L = Cpx +Ga + Cor + Sp, the position of the nonvariant point (An, Sp, Cpx, Cor, Ga, L), and the compositions of phases participating in these reactions. Based on a topological analysis of the studied segment of the system CaO–MgO–Al2O3–SiO2, we have substantiated that “eclogitization” must follow the reaction Opx + An + Sp = Cpx + Ga. A fundamental continuous series of eutectic monovariant equilibria was observed: L = Cpx + Opx + Fo + An, L = Cpx + Opx + An + Sp, L = Cpx (+ Ga) + An + Sp, and L = Cpx + Cor (+ Ga) + An. A change in the melt composition in this series of eutectic reactions depending on pressure must reflect the most likely magma genesis trend in nature. Comparision of the composition fields in which the above series of reactions is observed with the composition fields of the rocks of magmatic formations showed that this series is most similar to the alkali-earth series of rocks. The mineralogical compositions of cumulates and phenocrysts found in the effusive and dike varieties of these rocks correspond to unique sets of subsolidus phase associations and individual subsolidus phases crystallizing in this fundamental eutectic series.

Features of present-day channel deformations of the Tom' River within the Tomsk region and related processes of the ice jams’ formation have been considered. Recommendations about prevention of their negative consequences have been offered. They include organizational, scientific/information and engineering measures of the damages prevention against dangerous hydrological processes under consideration.

The subducting oceanic crust has a heterogeneous composition but mainly is composed of a mixture of anhydrous dolerite and gabbro with mafic green schist (albite + epidote + chlorite + actinolite) and amphib� olite [1]. An increase in pressure and temperature results in rock dehydration in the subducting oceanic crust [2]. As this takes place, dehydration proceeds successively depending on phase transitions in hydrous phases (chlorite, lawsonite, amphibole, phengite, zoisite–clinozoisite, and others). The sub� ducting oceanic crust contains >5 wt % Н2О at the ini�

During the last five years there has been considerable doubt over the age of the continental uppermost Permian Russian stages, the Kazanian and Tatarian. Traditionally they have been regarded as Late Permian but were re-dated as Middle Permian in the 2004 international time scale, despite fossil evidence that the Tatarian, at least, is Late Permian. These debated ages are tested by magnetostratigraphic study of five sections spanning the Permian Triassic Boundary (PTB) of the SE Urals in the Orenburg region of Russia. The Upper Permian and Lower Triassic of this region have a well documented vertebrate fauna whose evolution has a significant bearing on our understanding of the PTB mass extinction event. If the Tatarian is viewed as Mid Permian, then the Late Permian in Russia is marked by a 9–10 Ma stratigraphic gap. The palaeomagnetic data yield a distinct series of polarity zones that provide clear local and regional correlation and are readily tied to a recently compiled global magnetostratigraphic record. On the basis of this correlation the sampled sections span the upper Guadalupian to Induan stages without any obvious break, so confirming the traditional view that the Tatarian is Late Permian in age. Anomalies in the magnetic inclination are consistent with sediment compaction (inclination shallowing, a common phenomenon of red beds) but declination anomalies between these sites and elsewhere in Russia may suggest localised vertical axis rotation.

The distribution of neck muscles and the shape of the skull shows that Permian and Triassic dicynodontsmay be classified into three categories which probably reflect feeding on low, medium and high vegetation. These are distinguished on the basis of the occipital index, the difference between the relative width and height of the occiput, which gives a measure of the relative importance of the lateral and the dorsoventral clusters of neck muscles. The basicranium is relatively shortened in Triassic forms, except in Vinceria, Shansiodon, Tetragonias, and Jachaleria, as has been noted before. Data on skull proportions indicates that the height of the parietal crest may be of little taxonomic use, and that the genus Tetragonias is not a clade. Dicynodonts with dietary preferences at the intermediate level correspondto major branching points in dicynodont phylogeny. High-level feeding adaptations among dicynodonts arose by the middle of the Tatarian (latest Permian) and lasted until the Late Triassic....

The intensity of postmagmatic processes in the Botuobinskaya pipe kimberlites was estimated from the calculated content of normative secondary quartz (Q). Several simple algorithms are proposed to calculate the Q content from chemical analyses of kimberlites. Ten groups of altered kimberlites have been recognized from the Q contents. The contents of MgO, some trace elements, and LREE in the groups, the contents of Cr and Ca of crimson garnets, the diamond contents of kimberlites, and the average weight of diamonds decrease as the Q content increases. It is shown that the negative SiO2–MgO correlation is the most effective indicator of the postmagmatic alteration of kimberlites. As the degree of their secondary alteration increases, the kimberlites transform into an assemblage of quartz and clay minerals enriched in some trace elements and almost completely lacking REE and diamonds.

Large footprints of terrestrial tetrapods have been found in the Cis-Urals region of European Russia. The foot- print horizon is in Late Permian (Changhsingian) deposits of the Vyatkian Gorizont (uppermost Tatarian) approximately 50 m below the local Permian ⁄ Triassic boundary. Seventeen randomly orientated footprints were excavated and are referred to the ichnospecies Brontopus giganteus. The foot- prints were emplaced in a reddish-brown mudstone that was deposited from suspension beneath shallow ponded water in a floodplain environment. They were subsequently cast by the base of the overlying fine-grained sandstone, which was deposited from a sheet-flood event. The footprints were pro- duced by a large therapsid, possibly a dinocephalian, but more probably a dicynodont, and represent the first ichnological record of the Therapsida from the Upper Permian of Russia.

Thermochemical plumes develop at the core-mantle boundary in the presence of a heat flow from the outer core and at local chemical doping that decreases the melting temperature near the bottom of the lower mantle (this dope triggers the melting of the mantle material and the ascent of the plume). The paper presents evaluations for the heat power of the Hawaiian and Iceland plumes and the results of the experimental modeling of a thermochemical plume. The diameter of a plume conduit was determined to remain virtually unchanging in the course of plume ascent. When the top of a plume reaches a “refractory” layer, whose melting temperature is higher than the melt temperature in the plume conduit, a mushroom-shaped head of the plume develops beneath the bottom of this layer. The analysis of geological and geophysical data and the results of experimental modeling are used to develop a thermal physical model for a thermochemical plume. The balance relations for the mass and thermal energy and systematic tendencies in the heat and mass transfer during free convection were utilized to derive a system of equations for the heat and mass transfer of a thermochemical plume. Parameters were determined for a thermochemical plume ascending from the core-mantle boundary. Geodynamic processes are considered that occur during the ascent of a plume before it reaches the surface. The effect of the P-T conditions on the shape and size of a plume roof is analyzed, and a model is proposed for mass transfer between a thermochemical plume and the lithosphere, when the plume reaches the bottom of a “refractory” layer in the lithosphere.

A mechanism of ULF geomagnetic field perturbations caused by rock fracture and tectonic activity is studied. It is assumed that the rock fracture is accompanied by crack-generated seismic emission due to cracks pile up at underground cracked zones. Temporal series of seismic impulses due to the crack growth is supposed to be a stationary random process, which obeys Poisson distribution. The seismic emission of the cracks results in excitation of electric current due to motion of the conductive ground in the geomagnetic field, that is so-called diamagnetic effect in moving conductors immersed in the external magnetic field. The electric currents build up as a result of the random displacements in the conductive rock, which in turn leads to the random perturbations of the geomagnetic field. Acoustic wave field derivable from the crack seismic moment is used in order to obtain the electromagnetic variations due to growth of single crack. Averaging of these variations over random crack plane orientation and over crack sizes gives an assessment of mean level of the electromagnetic noise produced by the evolution of the crack ensemble. This assessment is consistent in magnitude with the ULF electromagnetic variations recorded prior to and after some strong earthquakes.

The thickness of coastal landfast ice in the Sea of Okhotsk has been examined based on field data and thermodynamic modelling. The study sites were Saroma-ko Lagoon, Hokkaido and Kleye Strait, Sakhalin. The ice sheet has a two-layer structure: a granular snow–ice layer on top and a columnar ice layer below. In Saroma-ko Lagoon, the ice grows to 40–50 cm, with snow–ice portion of 10–100%. In Kleye Strait, the ice grows to about 100 cm, with a remarkable addition (on average 24 cm) during mid-March to mid-April due to snow–ice formation. A one-dimensional thermodynamic ice–snow model was calibrated with observed data and used to examine the thickness climatology; the snow component takes into account snow compaction, slush formation due to flooding, melting or rain and snow–ice growth. The model outcome showed reasonably good agreement for both sites. In Saroma-ko Lagoon, the calibration was based on four winters. The maximum annual ice thickness was in the model on average 3 cm below the observed one, 16 cm in the worst case; the model snow thickness was within 10 cm from the observed ones in February; and the date of ice breakup was on average biased late by 5 days and 11 days in the worst case. The model simulations predicted formation of slush layers and their persistency for 1–4 weeks in different winters. Climatological simulation resulted in mean maximum annual ice thickness of 32 cm, of which 15 cm was snow–ice. In Kleye Strait, the calibration was based on one ice season. The maximum annual ice thickness was 7 cm biased down, and the model snow thickness was within 10 cm from the observed level. Climatological simulation resulted in mean maximum annual ice thickness of 108 cm, of which 70 cm was congelation ice and 38 cm was snow–ice, and the ice season lasted from 5 November to 5 June. Thus, slush formation and its freezing are crucial in the study basin.

Fossil fishes and tetrapods (amphibians and reptiles) have been discovered at 81 localities in the Upper Permian of the Southern Urals area of European Russia. The first sites were found in the 1940s, and subsequent surveys have revealed many more. Broad-scale stratigraphic schemes have been published, but full documentation of the rich tetrapod faunas has not been presented before. The area of richest deposits covers some 900,000 km2 of territory between Samara on the River Volga in the NW, and Orenburg and Sakmara in the SW. A continental succession, some 3 km thick, of mudstones, siltstones, and sandstones, deposited on mudflats and in small rivers flowing off the Ural Mountain chain, span the last two stages of the Permian (Kazanian, Tatarian). The succession is divided into seven successive units of Kazanian (Kalinovskaya, Osinovskaya, and Belebey svitas, in succession) and Tatarian age, which is further subdivided into the early Tatatian Urzhumian Gorizont (Bolshekinelskaya and Amanakskaya svitas, in succession), and the late Tatarian Severodvinian (Vyazovskaya and Malokinelskaya svitas, of equivalent age) and Vyatkian gorizonts (Kulchumovskaya and Kutulukskaya svitas, of equivalent age). This succession documents major climatic changes, with increasing aridity through the Late Permian. The climate changes are manifested in changing sedimentation and the spread of dryland plants, and peak aridity was achieved right at the Permo–Triassic (PTr) boundary, coincident with global warming. Uplift of the Urals and extinction of land plants led to stripping of soils and massive run-off from the mountains; these phenomena have been identified at the PTr boundary elsewhere (South Africa, Australia) and this may be a key part of the end-Permian mass extinction. The succession of Late Permian fish and tetrapod faunas in Russia documents their richness and diversity before the mass extinction. The terminal Permian Kulchomovskaya and Kutulukskaya svitas have yielded respectively some 6 and 13 species of fishes (sharks, bony fishes, lungfishes) and 11 and 14 species of tetrapods (aquatic amphibians, herbivorous and carnivorous reptiles of all sizes up to the hippo-sized pareiasaurs and sabre-toothed gorgonopsians). Immediately following the end-Permian environmental catastrophe, earliest Triassic faunas consisted only of a few fish taxa and small, aquatic tetrapods, in low-diversity, low-abundance assemblages.

A new mechanism for the ionospheric Alfvén resonator (IAR) excitation at middle latitudes is considered. It is shown that the ionosphere wind system in this region is capable of sustaining the generation of geomagnetic perturbations that can be detected by ground magnetometers. The general IAR dispersion relation describing the linear coupling of the shear Alfvén and fast magnetosonic/compressional modes is obtained. The dependence of the IAR eigenfrequencies and damping rates on the perpendicular wave number and on the ground conductivity during the day- and nighttime conditions is analyzed both analytically and numerically. In order to demonstrate the IAR excitation by neutral winds the power spectra of the geomagnetic perturbation on the ground surface are calculated. Furthermore, it is found that Kolmogorov spectra of the ionospheric turbulent neutral winds and the IAR eigenfrequencies lie in the same frequency range that make it possible to enhance the IAR excitation. The relevance of the developed theoretical model to the ground-based observations is stressed.

Fossil tetrapods (amphibians and reptiles) have been discovered at 206 localities in the Lower and Middle Triassic of the southern Urals area of European Russia. The first sites were found in the 1940s, and subsequent surveys, from the 1960s to the present day, have revealed many more. Broad-scale stratigraphic schemes have been published, but full documentation of the rich tetrapod faunas has not been presented before. The area of richest deposits covers some 900,000 km 2 of territory between Samara on the River Volga in the NW, and Orenburg and Sakmara in the SW. Continental sedimentary deposits, consisting of mudstones, siltstones, sandstones, and conglomerates deposited by rivers flowing off the Ural Mountain chain, span much of the Lower and Middle Triassic (Induan, Olenekian, Anisian, Ladinian). The succession is divided into seven successive svitas, or assemblages: Kopanskaya (Induan), Staritskaya, Kzylsaiskaya, Gostevskaya, and Petropavlovskaya (all Olenekian), Donguz (Anisian), and Bukobay (Ladinian). This succession, comprising up to 3.5 km of fluvial and lacustrine sediments, documents major climatic changes. At the beginning of the Early Triassic, arid-zone facies were widely developed, aeolian, piedmont and proluvium. These were replaced by fluvial facies, with some features indicating aridity. At the end of the Middle Triassic, deltaic and lacustrine-marsh formations were dominant, indicating more humid conditions. The succession of Early to Mid Triassic tetrapod faunas documents the recovery of life after the end-Permian mass extinction. The earliest faunas consist only of small, aquatic tetrapods, in low-diversity, low-abundance assemblages. Climbing the succession through the Early Triassic, more terrestrially adapted tetrapods appear, and larger herbivorous and carnivorous reptiles come to dominate in the Mid Triassic as ecosystems were rebuilt.

Electrokinetic phenomena in a water-porous medium with a fractal structure above percolation threshold are theoretically investigated. Fracture zone with space-variable porosity is considered as a model of an earthquake hypocenter zone in which the electrokinetic current results from fluid filtration in a fractal pore network. A critical exponent of the streaming potential coefficient is found to depend on both the transport critical exponent and correlation length critical exponent. In this model, logarithmic dependence of electric field amplitude E on the earthquake magnitude M is derived which is compatible with the one observed by the VAN group. Without fractal properties, this form of dependence contradicts the empirical data. The electromagnetic field far from the hypocenter is calculated, which leads to the prediction of weak magnetic field variations. To explain the observed amplitude of VAN's Seismic Electric Signals (SES), the electric source must be at a distance of about 10 km from the registration point if the medium is homogeneous. Therefore, some conductive channel(s) are needed to explain the long distance selective SES transmission.

The short-term EQ prediction on the basis of non-seismic technique is an intriguing problem since conventional seismic techniques provide us with long-term EQ forecast but cannot predict an impending EQ a few days or hours before main seismic event. Our prime interest is in the theories which are capable of explaining different electromagnetic phenomena possibly related to the EQs. In this chapter we consider the theories of ULF electromagnetic noise produced by rock fracture and crack formation. Here we explore GMPs, electrokinetic effect, variations of the rock basement conductivity, ionospheric perturbations, and other physical mechanisms which have been studied in previous chapters. Particular emphasis has been placed on the problem of direction finding for the ULF electromagnetic source. In the remainder of this chapter we discuss electromagnetic phenomena associated with large-scale natural disasters such as volcano eruptions, tsunamis, and hurricanes.

Basics of electrokinetic and seismoelectric phenomena in water-saturated rocks are discussed in this chapter. We study electrochemical and hydrodynamical processes in the fluid flowing in pores space in order to derive the relationship between the electrokinetic current and pore pressure gradient. Then we focus on the electrokinetic effect in anisotropical and fractal media. The remainder of this chapter covers seismoelectric effect caused by seismic waves.

In previous chapters we discussed the magnetospheric, ionospheric, and atmospheric sources of the ULF electromagnetic fields. The main emphasis has been put on studies of the global lightning activity, which results in an energy storage inside the resonators followed by the excitation of global electromagnetic resonances such as Schumann and IAR resonances. Furthermore, there are a variety of other terrestrial and atmospheric causes for the generation of ULF electromagnetic fields: ocean waves, tsunami, volcanic eruptions, earthquakes (EQs), meteoritic falls to the atmosphere, as well as the man-made sources such as the stray current, atmospheric and underground explosions, and so on. It is usually the case that the large-scale ULF perturbations resulted from the magnetospheric sources and lightning activity can be easily distinguished from the terrestrial fields and different kinds of local noises but sometimes there are a few problems because the terrestrial fields may be very weak.

It is planned that the LUNA-GLOB spacecraft will deliver an orbiter and 14 landers to the Moon. The schematic diagram of the spacecraft flight to the Moon is shown in Fig. 1 Download : Download high-res image (148KB) Download : Download full-size image Fig. 1 . Schematic diagram of the LUNA-GLOB SC flight to the Moon. . The flight time is estimated at 4.5 days. Some 33 h before the spacecraft approaches the Moon a container with 10 small high-velocity penetrators (SHVP) will be separated from the spacecraft. It will continue the flight to the Moon autonomously. When the container is at a close distance to the Moon it will intensively rotate, and the penetrators will be separated from it. They will continue their flight to the Moon, and at a rate of 2.6 km⧸s, they will penetrate the surface. Then, two large penetrators (LP) will separate and continue the flight autonomously. In due time they will decelerate and penetrate the surface at a rate of 80–100 m⧸s. Finally, after leaving the satellite orbit the polar station (PS) will land to the South Polar Region at a rate of 80–100 m⧸s. All 12 penetrators, which will be dropped from the spacecraft, have seismometers. They are intended for the research into the internal structure of the Moon that is one of the main scientific objectives of the project. The (PS) accommodates a complex of instruments intended for the solution of another objective of the project: the search for volatiles.