The largest in the Jurassic, The Early Toarcian transgression in the eastern Siberian platform and its folded framing (Arctic superbasin regime, thalassocratic factor) was accompanied by extensive inversion of the arch of the Yakut buried uplift and the conjugate Tompo block to the east, as well as by the formation of volcanites of the Pliensbachian–Aalenian Kobyuma Suite (Pacific superbasin regime, geocratic factor). At the same time (the Danlap phase of tectonic activity) in the zone of junction of the Siberian platform and the Verkhoyansk fold–and–thrust belt (the Lena branch of the Priverkhoyansk foredeep), a key Early Toarcian clay horizon of the Vilyui syneclise was locally accumulating on a relatively steep paleo–slope. The horizon is lacking in the section of the Aldan branch of the foredeep, and near the northwestern boundary of the Vilyui syneclise (Tyung River basin) the Suntar Suite is found to transgressively overlie the carbonate base of the Upper Cambrian. The stratigraphic unconformity on the Tyung River is proved by new paleontological finds. The lack of Hettangian–Pliensbachian rocks and the fact that the Upper Cambrian carbonate base is transgressively overlain by the Upper Lias deposits permits establishing a new «Mastakh» type of the section of Jurassic marine rocks in the Vilyui syneclise.

The Rephean sediments of East of the Aldan anticlise are believed to have important significance for formation of hydrocarbons accumulations. The organic matter of Rephean sediments study has been made. Corg content in rocks as chloroform bitumoids yield has been determined. Structure-group composition of bitumoids has been studied by FT-IR spectroscopy. The quantity of hydrocarbons, resins and asphaltenes has been detected. Some samples have been studied by methods of gas-liquid chromatography and chromatograph-mass-spectrometry for identification of individual hydrocarbons and study of moleculebiomarkers. Distribution character of organic carbon and chloroform bitumoids content along the section of Middle-Later Rephean sediments had been analyzed (from Malginskaya to Ignikanskaya suites). It has been defined that the bitumoids have aliphatic composition, close distribution of hydrocarbons-biomarkers and absence of 12-и 13-methylalkanes (with the exception one sample). Significant variations of hydrocarbons, resins and asphaltenes content in bitumoids composition show presence of different bitumoids (autochtonous, paraautochtonous and mixed) and evidence of hydrocarbons migration processes. The Malginskaya formation (namely Upper part) is the most bituminous in comparison with the upper lied formations. According to geochemical parameters of organic matter and bitumoids the Malginskaya formation is concerned as oilproduced. Evidence of paraautochthonous bitumoids indicates the realization of oil-generating potential of the rocks.

General information about using in works for oil and gas a relatively new concept of «hard-to-recover hydrocarbon resources» is considered. The facts showing the existence of the hydrodynamic connectivity of previously identified gas deposits in the Mesozoic and Upper Permian sediments for Khapchagaysky petroleum district dedicated to the eponymous arched uplift of the first order in the eastern part of Vilyui syneclise, are presented. The arguments which can be taken into account in discussions about the possible existence of the largest gas deposit of a massive type in the section of the Upper Permian, controlled by Khapchagaysky uplift are described. A conditional model of a possible joint development of gas reserves in traditional collectors and of predictable resources in deeper horizons of the mantle with solid low permeable rocks are suggested. Recommendations for a wide application of the proposed methodological approach in the sediments of different age and lithology, including oil and gas fields of Vilyuisk region as a whole and beyond it.

In the eastern part of the Siberian platform, Phanerozoic magmatism manifested itself in various tectonic structures. It was related, in Middle Paleozoic and Lower Triassic times, to rifting processes, and in Late Paleozoic – Early Mesozoic times – to the initiation and development of traps. Varying geodynamic regime of magma generation resulted in a geochemical variety of the rocks. The Permo-Triassic traps are characterized by a low content of incompatible elements, insignificant REE totals (60–70 ppm), a moderate degree of fractionation (La/Yb)n=2.0–2.8 and the presence of a Ta-Nb minimum. By the amount of incompatible elements and their position on the correlation diagrams the traps are similar to E-MORB, which suggests that source rocks of this composition played a leading role in their formation. Middle Paleozoic rifting was accompanied by the formation of dike swarms and by eruptions of basalts. Characteristics of the rift-related Devonian basites are a high content of incompatible elements, significant REE differentiation (La/Yb)n=4.3–5.4 and a positive Ta-Nb anomaly. Geochemically, dolerites of the dike swarm are close to OIB, and effusive rocks on spider and correlation diagrams of elements are plotted between the values for E-MORB and OIB. A distinctive geochemical feature of trachydolerites is the highest content of incompatible elements, the character of REE distribution is distinguished by significant fractionation (La/Yb)n=23. On the correlation diagrams of incompatible elements, compositions of Phanerozoic basites exhibit a general trend from the EMORB field through OIB to the field of higher contents in trachydolerites.

The results of geophysical works in different areas of Bazovskoe deposit are given. The study tested possibilities of high accurate magnetic prospecting, electric prospecting by median gradient and transient electromagnetic sounding when identifying and tracing ore-controlling structures, studying geological structure of the deposit. The analysis of the geophysical materials showed that methods of electric prospecting were the most informative. Transient electromagnetic sounding allows obtaining volume information on deep geologic structure of the studied object in bad grounding conditions. Three-layer structure of geoelectrical section of the deposit is identified according to transient electromagnetic sounding data. Magnetometry in combination with electric prospecting data makes possible to geologically interpret geophysical information with greater reliability. It is determined that, ore-controlling structures in electric fields are manifested by extended linear anomalies of decreased and increased conductivity, that is connected with mineralization features. In magnetic field, mineralized zones of crush are manifested, mainly, by negative linear anomalies.

The methods of coal ash content determination by selective micro-gamma-gamma ray logging, on the basis of established correlative relationship of geophysical parameter and ash content, as well as the method based on multifunctional relationships of coal ash content with its geophysical data are considered. The mathematical modeling scheme of coal quality indicators based on the usage of Markovian processes mathematical tool is also considered. Prospective lines of physic-mechanical properties survey in the rock mass and prediction of rock wall stability according to the received data on physic-mechanical mass properties on the results of borehole survey are offered.

The results of modeling of spatial distribution of earthquakes in northeastern segment of the Amur microplate in various magnitude intervals in the range of 120⁰Е to 140⁰Е are presented. The seismicity dynamics in the different phases of change of the Earth's rotation speed is established. It is suggested to group the seismic events on the time of their occurrence in two phases of change of speed of the Earth rotation of «deceleration-acceleration». It is shown that the earthquake within the magnitudes interval from M=5 to M=6, united by phases of seismic activity in the annual cycle, are grouped into clusters, which regularly alternate in the space of an average of (3.5–40). For the earthquakes in the magnitude range from M=2 to M=4 three lineaments are distinguished which spatially combine fault systems of the Stanovoy Ridge and the Tan-Lu fracture zones of different kinematics and azimuths stretch. A supposition is made about the collective fault activation on a background of random seismicity process.

The paper represents main stages of the development of Laboratory of carbon dating established in the Permafrost Institute SB RAS, which work is based on the classical method of liquid scintillation analysis using a spectrometer-radiometer Quantulus 1220. In 2014 Radiocarbon Laboratory initiated creation of an electronic database of radiocarbon dating standards, in which the authors (collectors) of the samples are named, as well as the precise coordinates of the sampling. This article presents a list of 32 dates performed in 2014. A brief description of the individual and unique dates and sections that play an important role for the understanding of Late Pleistocene and Holocene natural history of Yakutia.

Structures of bushy type, calcified, rock forming microfossil of Dzhelindia Kolosov 1970 genus, widely spread in the Upper Riphean deposits of Siberia, and organic-walled microfossil of Ulophyton Timofeev et German 1979 genus, according to their biologic interpretation are included into Cambrinaceae Korde family (Cambrinales Korde order, Ptotofloridomorphophyceae Korde class, Rhodophyta division). In this family they are compared with the Cambrian Filaria Korde, 1973 and Razumovskia Vologdin, 1939, genera, according to bushy structure of the thallus from uniserial branching, rising filaments with places of vegetative reproduction at different places of filaments and due to belonging to benthic algae ecologic group.

At negative Celsius temperatures the phase composition of pore water determines the whole spectrum of rocks’ and construction materials’ properties. It has a dominant role in the physical, chemical and mechanical processes which take place in them. The paper presents some results of the phase transitions study of pore solutions in a variety of soils over a wide range of negative temperatures. The studies of NaCl, CaCl2 pore solutions phase transitions in sand, loam and clay were carried out using a differential scanning calorimeter DSC L63. The concentration of NaCl and CaCl2 solutions varied from 5 to 20%. The samples were cooled down from a room temperature to an initial temperature of -100°C at the rate of 5 °C/min. After being kept at an initial temperature for 30 min, the samples were heated to 10°C at the rate of 2°C/min. The studies confirm the complex nature of the influence of rock’s hard skeleton onto the phase equilibrium conditions of the pore solution, and show the need for detailed studies of the saline soils phase composition in each particular case. It is shown that rock’s hard skeleton and solutes are the factors influencing the shift of the eutectic temperatures, which depends on the dispersion of the hard skeleton and pore solution concentration.

Proposals for improving the design of rock cutting tool (bit) during drilling in permafrost conditions in areas of the North-East and Arctic regions are considered. The extreme climatic conditions of the regions and thick layers of permafrost rocks bring about special requirements for methods and technology of exploration. Deposits of the permafrost zone have significant differences from deposits located in areas with a temperate climate and positive temperature rocks due to a complex interaction and the influence of geological, mining, permafrost and climatic factors. The basis of the complicated conditions of drilling in permafrost temperature is the temperature factor that determines the efficiency of the process of destruction and transportation of frozen rocks. In the process of destruction of frozen rocks, upon contact of the cutters with rocks in the area of the working surface of incisors the heat dissipation is enhanced. Analytical studies of the regularities of heat formation on the surface of the incisors are carried out and the dependence of heat generated on the wellbore from the radius of the rock cutting tool (bit) cutters location T=f(r) when cutting frozen rocks is revealed. On the basis of the obtained data, we propose an improved version of rock cutting tool (bit), which provides effective destruction of the borehole bottom and minimizes the heating.

A short review is given and new methods of the development of small-volume kimberlite fields and excavation of undersurface and undermine reserves of diamonds are suggested. The essence of the drilling method is that an ore field is divided into adjacent to each other regular hexagons with sides equal to the diameter of a drilling well. Then of kimberlite cores of large diameter with the centers at the apexes and in the center of the regular hexagons are drilled. The cores are cutted by mechanical method from the cavity of the central well and are excavated by a self-propelled mobile crane. For cutting the core of the central well a secondary bore hole is bored in its center. It is shown that delivery to the surface of a mineral in the form of a core of large diameter allows a broader line of methods of further disintegration, than at a bottom hole. The novelty of the methods is confirmed by the patents of the Russian Federation. The feature of the methods is a possibility of their use as in geological exploration for pits and trenches, and in construction for deep holes and foundation pits.

The article presents the results of the research in the field of open pit mining transport development. The revealed regularities are described and the basic principles and provisions of the strategy of open pit mining transport systems formation are formulated. It is established that the establishment of the adaptive nature of open-cast mines transport systems development, revealing of the regularities and constraints of their formation, determining of the most likely forecast background along with the methods of prediction and the universal interactive model of functioning of complex open pit mining transport systems constitute the methodological basis of long-term and overlong-term forecasts of formation these transport systems, which should be based on new researches, clarifying and developing the theory of open pit mining transport systems formation. Promising directions of research are defined and some results in the theory of open pit mining transport are presented.

The results of rubber modification based on various rubbers for sealing materials with high frostand oilresistance are presented. Ultra high molecular weight polyethylene UHMWPE is used as the main modifier. It is established, that introduction of UHMWPE in rubber blend V-14 based on butadiene nitrile rubber BNRS18 allows to receive a protection film on the surface of cured samples with 70–80 mcm thickness, which provides of increase of oil resistance in 2.5 times. The coating technology of protection film from UHMWPE with the thickness up to 2 mm on the rubber samples based on BNRS-18, isoprene SRI-3 and butadiene SRD-2, which allowing to increase of oil resistance of the samples in 3, 23 and 26 times respectively is developed.

Physical and mechanical characteristics of engineering continuous basalt fiber plastics make them a promising material for various industries. Due to low weight and high corrosion resistance, these plastics provide the axis tensile strength along higher than most structural steels. However, the magnitude of the modulus of elasticity is still significantly lower. Therefore, the main research task now is an increasing the Young’s modulus of basalt fibers plastics. The objects of the study were selected experimental samples of combined basalt rods of various types with the diameter Ø8 mm, which were produced by the longitudinal and transverse winding of basalt fiber to a metal wire, combined with carbon portage and twisted in a spiral shape of individual unidirectional basalt rovings, impregnated and cured with 3-component epoxy-anhydride binder. A metal rod with a diameter of 4 mm brand BP-1 was used as the reinforcement material for basalt rod Ø8 mm, obtained by longitudinal-transverse winding. In the samples with a carbon fiber of reinforcing material was used Zoltek Carbon fiber with volume content of 25% in the composite. Experimental studies of physical-mechanical properties have shown that the 25% volume content of carbon fiber leads to the 29% increase of the limit of the tensile strength, and 90% growth of tension elasticity modulus. The ultimate strength in static bending is increased by 50%. It is revealed also that the destruction of the unidirectional composite rods is fragile with the bundle.

The article describes the main provisions and the application of a structured approach to building a multilevel model of damage accumulation and fracture of materials of different nature with the structure of defects at different scales.As the basis of the study an approach of micro-macroscopic physical modeling was adopted, which has been developed for complex multilevel (multiscale) systems with internal microstructure and evolving under the action of external factors. As a rule, this leads to the process of damage accumulation in the material, and subsequent fracture. The analysis of existing multi-level approaches has been done, and the possibility of creating full-scale models on the basis of theoretical analysis and experimental data has been discussed. The authors on the basis of works of domestic and foreign authors come to conclusion about the necessity of the experiment at submicroscopic level, allowing to quantify the process of damage accumulation and to identify the patterns of fracture. The novelty of the approach is the use of structural models and Verhulst logistic function to assess the evolution of damage at several structural levels, as well as direct experimental in situ observation of damage processes at the nanolevel. The study also describes the prospects of non-Markovian approach and Bayesian probability interpretation for safety evaluation and lifetime prediction of equipment operated in the North conditions.

A combined method of intensive plastic deformation combining extrusion and screw pressing is presented. The method has been realized in the developed device and allows to produce a metal screw profile from a strengthened ultrafine-grained material. The technological tooling and test parameters are described. The data about obtained ultrafine grain structure, mechanical properties of the low-alloyed steel subjected to the combined influence by extrusion and screw pressing are provided. After crushing of structure with grain refinement the steel durability increased by 1.4 times and its plasticity decreased by 38%. The analysis of the structure let us to assume that the material strengthening is caused by dispersive strengthening and increase of closeness of dislocations, unlike crushing and degradation of ferrite grains in case of strong extents of deformation, and also fragmentation the subgrain blocks at implementation of the scheme of pressing with hydrostatic pressure.

We have considered the fracture features of steel 09G2S obtained by equal channel angular pressing (ECAP) with subsequent tempering and tested at different temperatures of impact test. It is shown that the thermomechanical treatment led to a significant increase in strength coupled with high resistance to impact fracture, including low temperature tests. Found that immediately after ECAP there is a sharp decrease in toughness, which is due to a change of the main destruction mechanism from viscous patching in a coarse-grained condition to brittle fracture by quasi-spalling in ultrafine-grained state. Subsequent thermal treatment of the material had an obvious relaxing effect on the structure of the steel subjected to severe plastic deformation by the ECAP method, allowing it to maintain high strength of the material with simultaneous increase of impact values. It is established that quenching and subsequent short time heating after ECAP increased the energy of destruction more than 12 times at room temperature and almost 20 times at –60°C.

The results of a study of the influence of long operation on structure and mechanical properties of lowcarbon and low-alloy steel of the pipe of the main gas pipeline in Republic of Sakha (Yakutia) are presented. It is shown that structurally degradation processes proceeding on nanometer scale level lead to degradation of structure and properties on microand macro-levels. Destructions and damages of pipelines and the equipment of the gas industry at their long operation in conditions of the Arctic are considered and their interrelation with degradation of a physical and mechanical condition of the constructions metal is shown. The analysis of destructions and damages of the objects testifies about the necessity of development and use of new methods of nondestructive control, and that it is necessary to take into account the change of a physical and mechanical condition of pipes metal at long operation when standard documents regulating their building and operation are worked out.

Dynamics of change of fatty acids composition in the leaves of Amaranthus retroflexus, Thlaspi arvense and Agastache rugosa is investigated at their cultivation in Central Yakutia in the course of vegetation from June to August. The quantitative and qualitative content of saturated and unsaturated fatty acids in the leaves of the studied plants is revealed. The maximum quantity of fatty acids was fixed at the end of June, the minimum at the beginning of August. It is established that the main unsaturated fatty acid is the linolenic acid (С18:3Δ6,9,12), saturated palmitic acid (C16:0) in all studied plants. It is revealed that with decrease of temperature the percentage of unsaturated fatty acids at all three species of the studied plants increases. It is shown that the studied plants differently react to change of temperature conditions of their growth that displays in changes of their fatty acid composition. This may testify to various mechanisms of adaptation to a lowtemperature stress.

Changes of parameters of the human cardiovascular system (CVS) when a person is being exposed to sound waves of different frequencies are experimentally investigated. Classical music (Mozart) which presents the sounds in the frequency range (from 700 to 3000 Hz) and heavy music (style death metal, Cannibal Corpse) with ultra-low (15–30 Hz ) and ultra-high (up to 80 000 Hz) frequencies were used. Students-volunteers (18– 20 years old) of the indigenous nationality (the Yakuts) took part in the experiment. It was established that the classical music causes an increase of blood pressure in women, especially of systolic (SBP) in the group of extroverts and having high levels of neuroticism (p <0,001). Men with high levels of neuroticism, regardless of the level of extraversion, Mozart’s Sonata in D major causes a decrease (p <0,05) of the indices of the CVS. At different levels of neuroticism audition of heavy metal music has the opposite effect on men and women (p <0,05, r = 0,784). CVS indicators are rising among women and are falling in men. CVS parameters of extroverts, regardless of gender, reduce, while CVS parameters of introverts increase (p <0,05). The results suggest that changes in the parameters of the CVS under the influence of sound waves depend on gender and individual-typological (extraversion-introversion, neuroticism level) characteristics of a person.

The influence of a mineral composition of the nutrient solutions and new growth stimulants from a vegetable origin raw materials on the morphogenesis of Onobrychis arenaria in a culture of the tissue in vitro studied. The new growth stimulants from a vegetable origin raw materials, which were put into composition of the nutrient media for the recurrent regeneration and the micro-cloning multiplication of the onobrychis in concentration 0.5–1 mg/l, have an effect on the morphogenesis and permit to change the expensive synthetical cytokinins and the auxins, reduce the cultivation’s time in vitro in 1.5–2 times, increase the appearance of the scions and the frequency of rhizogenesis by 15–90%. The effectiveness of the antiseptic treatment of the seeds of the onobrychis with a mixture of ethanol and hydrogen dioxide achieves 97 % and the germination of the aseptic seeds under laboratory conditions is 72 %.

The protocols of the recurrent regeneration with nano-biocomposites as the alternatives of the synthetical plant hormones are worked out. The new selection biological technologies are applicable for creation of highly productive and longeval forms of onobrychis, which are resistent in conditions of the cryolithic zone.

The practicability of application of the structural-morphological approach to resolving the existing problems of the identification of ontogenetic stages of thick-root bunch grasses on the example of Festuca lenensis is shown. For Festuca lenensis ontogenesis 4 periods and 10 ontogenetic stages are revealed, biological criteria and morphological characteristics of the ontogenetic stages of the species are presented. Structural-morphological analysis of Festuca lenensis shoots and shoot systems is conducted using three categories of modules. Three elementary, two universal and 2 basic types of modules are identified. For the species the izomodular type of structure have been revealed, due to the uniformity of both universal and basic modules. It is shown that with the development of individuals, the same type of modules accumulates and the structural organization becomes more complex. At the same time each stage of this iterative process corresponds to a particular ontogenetic stage. This method is relevant for identification of ontogenetic stage of individuals in pregenerative period and is significantly simplified compared to the existing procedure for determination of ontogenetic stages. Using the structural-morphological approach the selection criteria of virginile stage of thick-root bunch grasses such as an emergence of shoots of III order and formation of a system of partial bunches (system basic module 1) are found out.

When assessing plants introduction abilities, one of the criteria determining the sustainability of a species in the culture is the duration of its cultivation. The plants have been classified into the following groups depending on the duration of their cultivation in the collection: highly sustainable species that have been a part of the collection without human intervention in its reproduction for 25 or more years; sustainable species whose longevity in the collection is supported by human intervention – annual seedlings or artificial vegetative propagation; unstable species that have been a part of the collection for less than 5 years and have been unable to reproduce even under the conditions of a nursery with the help of a human.

The data on the species composition of the genus Spiraea L. in Yakutia and its introduction into the Yakut Botanical Garden are presented. Totally 23 species, 5 forms are tested. 10 species combine highly decorative qualities with the resistance to adverse conditions. 5 species belong to the local flora and have the early and middle phenological rhythms. Spiraea media, S. dahurica, S. sericea belong to the group of spring-flowering spiraea. The species from other regions, S. betulifolia и S. salicifolia, have the middle and late phenological rhythms and are summer-blooming. Between them S. chamaedrifolia occupies an intermediate position. The variability of morphological features depends on the wetness and lighting of locus spirea. The most studied species of spirea are mesoxerophytes and only S. salicifolia is a mesohygrophyte. Variability of morphological features is influenced by moisture conditions and illumination of a place of growth of a spirea. High degree of variability was shown in damp habitats, and it was noted for signs of a gabitus of a bush and an inflorescence. Unpretentiousness to soil conditions, hardiness, high decorative quality of Spiraea allow to use it widely in landscaping.

To poikilothermic organisms it is particularly important the presence of a variety of adaptive mechanisms to successfully withstand to adverse environmental factors. The article deals with the environmental aspects of adaptation for the winter period of 6 species of grasshoppers living in Central Yakutia. The climate of Central Yakutia is one of the most severe and harsh continental in Eastern Siberia. The minimum soil temperatures in Central Yakutia in winter are close to the temperatures of the «Pole of Soil Cold», located in the basins of the Indigirka and Yana Rivers. Grasshopper eggs overwinter in the supercooled state in the soil under the snow, at depth of 3–5 cm. It is experimentally established that the eggs supercooling point (SCP) of 6 studied species of grasshoppers varies from –25 to –35 °C. The threshold temperature is continuously transferred in the range from –23 to –29 °C, and allows the eggs to safely survive severe winters. It is revealed that Omocestus haemorrhoidalis, Glyptobotrus maritimus jacutus and Gomphocerus sibiricus have higher reserve of cold hardiness, and Bryodemella tuberculata – the lower.

In the paper 25 species of Pamphiliidae sawflies are presented, 2 of which (Cephalcia pallidula Guss., Pamphilius hortorum Kl.) are firstly recorded for the fauna of Yakutia. Brief characteristics of zoogeographical and ecological features, literature data, studied material are given for each species. Arealogical analysis showed that large part of fauna (11 species) has wide trans-euroasiatic distribution. By trophic relations it was showed that 16 species are narrow oligophages and 6 species are wide oligophages. By imago's flight activities all of the species of Pamphiliidae family belong to a summer group. Economic importance of Pamphillidae sawflies is insignificantly because Pamphiliidae sawflies have no outbreaks of mass reproduction in severe climate of Yakutia.

The phenology of 25 species of damselflies and dragonflies in the cryosemiarid conditions of Central Yakutia is studied. Total flight activity of the imago is continued during 5 months from May to September. Six seasonal groups are revealed: hibernating – the first 10 days of May – the last 10 days of August (Sympecma paedisca), late spring-summer – the last 10 days of May – the last 10 days of July (3 species), late spring-late summer – the last 10 days of May – the last 10 days of August (1), summer – 10 days in the middle of June – the last 10 days of July (9), summer-late summer – 10 days in the middle of June – the first 10 days of September (9), and the summer-autumn – 10 days in the middle of July – the last 10 days of September (2 species). Emergence of damselflies and dragonflies from reservoirs occur within seventy days from the last 10 days of May to the last 10 days of July and their greatest diversity (25 species) is observed in the period from the 11th to the end of July. The period of seasonal flight activity of adults Odonata in the investigated area essentially does not differ from the period of flight in the North-East of the European part of Russia. The terms of flight of damselflies and dragonflies in the Central Yakutia, in comparison with phenological data of the north of the Far East appear longer for a month, and is shorter for a month than in the south of Siberia and the Far East.

In the summer of 2015 moisture regimes of permafrost meadow-chernozem soil under rainfed and irrigation in the area «Moydooh» of the agricultural firm «Nemyugyu» (3 km from the town of Pokrovsk) in the Khangalassky district of the Republic of Sakha (Yakutia) were studied. Summer of 2015 was extremely dry, and therefore on rainfed area due to extreme shortage of moisture in the root zone the crop of green mass of oats was 70 kg / ha., while at the irrigated ones thanks to irrigations (irrigation rate of 900 m³/ ha.) , the yield was 1.5 times higher. For the period from the 18^th of June to the 18^th of August 2015 the total water consumption in the irrigated area was 132 mm, and in the rainfed area – 65 mm. At the same time at both sites the main quantity of moisture was coming from the top half-meter of the soil strata.