GEOLOGY, PROSPECTING AND EXPLORATION OF OIL AND GAS FIELDS
The article briefly covers the entire period of the Trans-Urals exploration, including Kurgan region. We report the main historical events of the process of prospecting for oil and gas. As a result of geological exploration, the industrial oil content of Cretaceous and Jurassic sediments have been identified, and powerful sequences of carbonate rocks of the pre-Jurassic age in Vagay-Ishim depression (the territory of Kurgan region) have been developed. It should be noted that the discovered sequences of carbonate rocks under favorable structural and tectonic conditions could be productive for oil and gas.
The article deal with a new approach to the assessment of geological and technological efficiency of the implementation of the remedial cementing (a case study of water shut-off treatment) in the productive part of Vikulov suite in order to limit the level of water inflow into the near-well area of the array and maximize the duration of waterless period of crude oil production in the conditions of two-phase filtration.
The article is devoted to a generalization of the obtained empirical material on modern geodeformation processes. For this, we used the basic methods of analysis and interpretation of the received information. In addition, we show the possibility of using the results of geodynamic monitoring in order to ensure industrial safety of urban development facilities in Pyt-Yakh from the harmful effects of the development of the Mamontovskoye oil field. The main conceptual scheme of interpretation of the obtained data is reduced to solving the inverse problems of modern fault geodynamics and identifying the sources of formation of local anomalies of stress-strain state of the subsoil.
Geometric leveling of class II accuracy, high-precision satellite observations, high-precision gravimetry and satellite radar interferometry were used as the main methods of analysis.
The article presents results and findings of the research into stratification of the hydrogeological section of western areas of the Yenisei-Khatanga basin localized in the Siberian Arctic zone. The identified two hydrogeological structural stages in the study area include the Paleozoic (undivided), Triassic, Lower-Middle Jurassic, Upper Jurassic, Neocomian, Aptian-Albian-Cenomanian, Upper Cretaceous and Paleogene-Quaternary water-bearing complexes. There have been recognized as many as eleven aquifers and eleven confining beds formed within the area where the established hydrogeological units are found not ubiquitously distributed, which is associated with the sedimentary basin evolution. A considerable part of the horizons have failed to be included in the hydrogeological section either due to the erosion processes within the Messoyakha inclined ridge or their pinching out in the borders of the basin.
DRILLING OF WELLS AND FIELDS DEVELOPMENT
The development of the theory and application experience of enhanced oil recovery methods comes to the fore in the conditions of depletion of traditional reserves. Russia has accumulated quite a lot of experience in applying gas enhanced oil recovery methods that have been tested at the Romashkino oil field, the Samotlor oil field, the Fedorovskoe oil field, etc. The maximum efficiency in the application of gas drive methods is achieved under the condition of miscibility or full solubility of the injected gas and reservoir oil. Therefore, an analysis of the gas methods applicability begins from the investigation of miscibility conditions assessment. Experimental study of miscibility conditions is a time consuming and expensive procedure. A large number of correlation dependencies taking into account the reservoir temperature and the composition of oil and gas - a candidate for injection into the reservoir were proposed in the technical literature for the initial assessment of miscibility. Most of these dependencies are defined for petroleum occurring in different parts of the world and diverse sediments. An analysis of the applicability of these correlations for the fields, which are located in Western Siberia, is an actual task.
The article compares the results of calculations for more than ten correlation dependencies with experimental data for determining the miscibility conditions, performed on of slim tubes models, a case study of the Samotlor oil field. The comparison is made for both carbon dioxide and enriched hydrocarbon gases.
The development of reef deposits is complicated by the high variability of the geological and physical properties of the reservoir along strike and section, as well as the variability of the rheological properties of oil within the reservoir. The level of interaction between wells before they are put into production is not predictable. In such conditions, the organization of an effective system of stimulation of the reservoir is associated with the solution of many unique in each case technological problems. Using the example of a group of reef deposits, the experience of introducing exposure systems by various agents and their combinations (water, gas, water-gas) is summarized. It is shown that the exhaustion of natural reservoir energy is not the basis for stopping the development of an isolated section of the reef deposit. It is necessary to assess the primary direction of filtration according to the development history for the formation of a set of measures using the information received (changing the direction of filtration flows, changing or combining displacing agents), including the information for areas consisting of only two wells. The reaction features of producing wells that provide the basis for the use of flow deflect technologies are highlighted.
The article is devoted to the conclusion of a semi-empirical dependence for calculating the volume coefficient of gas-saturated oils. For this calculation, the author of the article used expressions, which have been calculated earlier; the first expression is the expression of dependence for determining the volume coefficient at a gas saturation pressure of oils; the second expression is the expression for the compressibility factor of such oils. These dependences are based on a hypothetical model of the molecular structure of gas-saturated oils, developed on the basis of the J. I. Frenkel's hole theory of liquids. This fact, the physical validity of these expressions, and the basing of the obtained expression on a generally accepted dependence for determining the compressibility coefficient of a liquid under laboratory conditions give the final semi-empirical expression a theoretical character and ensure its applicability for a wide range of oils, which is confirmed by the verification of the expression, which is obtained in the article.
The article is devoted to the study of tributary profiles arising from the selection of hydrocarbons from partially opened reservoirs. The calculations were performed based on the finite-difference program for calculating the pressure and velocity fields in the formation, based on the solution of the problem of the pressure field in an isolated isotropic homogeneous formation, localized in the range from H1 to − H2 and perforated in the range −H < z < H, which is completely contained in the interval of the reservoir.
Graphical dependencies are constructed for the pressure field, the vertical and horizontal components, and the velocity modulus of the fluid filtered from the periphery to the well. Level lines for the indicated fields are presented and, based on their analysis, important regularities of the flow are revealed. A computational experiment showed that there are no vertical flows at the hole in the perforated part of the formation, and when they are removed from the well, they are non-zero. It was shown that interlayer flows exist even in homogeneous partially opened formations. At the same time, the inflow from an imperfectly opened homogeneous isotropic reservoir producing in a given depression mode is not uniform, and the maximum modulus of the horizontal velocity component in all curves is reached at the boundaries of the perforation interval. It is shown that in the center of a symmetrically perforated and imperfectly opened formation a minimum specific inflow is observed.
Currently, the use of jet devices in the oil and gas industry is constantly expanding. The reason for this expansion in the oil and gas industry is the presence of a number of advantages. One of the advantages is the compactness of the working section. Other advantages of the jet pump are the simplicity of its de-sign, high reliability and unique technical capabilities when pumping gas-liquid mixtures, the absence of moving mechanical parts, low criticality to the content of mechanical impurities and viscosity of the extracted liquid.
The aim of the study is to analyze the use of jet devices during well develop-ment in Western Siberia.
MACHINERY, EQUIPMENT AND FIELD CONSTRUCTION
The article is devoted to the modeling of physical and chemical creep process, which determines the plastic strength of cutting parts at the vertices of the tools from STM. The creep process is associated with the phenomena of diffusion and diffusion wear of the tool from STM in the zone of quasi-brittle transition (that is, the temperature transition of tool STM from brittle to plastic state at high cut-ting temperatures) with thin turning of heat-resistant alloys and steels. Turning of heat-resistant alloys at high cutting temperatures, corresponding to the quasi-brittle transition, allows the machining process at ultra-high cutting speeds, which expands the application of tools from STM. We have created mathematical model of wear and destruction of the cutting part at the top of the tool and STM due to diffusion phenomena in the process of thin turning of a heat-resistant alloy.
The subgrade design concept on permafrost soils was developed in the last century, and currently it are still used in the highway engineering by design organizations. However, this design concept doesn't provide the required stability of the subgrade that leads to premature destruction of road pavement. One of the main reasons for the destruction of road pavement is the lack of accounting for the processes of heat and moisture transfer of the "atmosphere — embankment — active base layer" system. When filling the subgrade with loosely frozen soils and dry frozen soils, the estimated embankment height according to the first principle is 2,0–2,5 m. Nevertheless, in summer the embankment soils, but also the active base layer is thawed by filtering water. This leads to additional waterlogging of the active layer and the occurrence of deformations of the settlement of the subgrade and road pavement. In winter the water potential thus accumulated migrates to the freezing zone, and due to the forces of frost heaving, expansion and cracking de-formations of the embankment soils appear. Therefore, the development of structures using geotechnical materials is necessary for reliable regulation of the water-thermal regime of the embankment.
DESIGNING, CONSTRUCTION AND OPERATION OF PIPELINE TRANSPORT SYSTEM
The article developed a finite-element model of a tank for storing liquefied natural gas. The influence of the damping coefficient of laminated rubbers on the movement of the tank and the acceleration of the stored product at different frequencies of seismic waves is numerically studied. Graphic dependences of the displacement and acceleration of the structure along the height of the wall are established.