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Date submitted2023-04-04
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Date accepted2023-09-20
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Date published2024-08-26
Association of quartz, Cr-pyrope and Cr-diopside in mantle xenolith in V.Grib kimberlite pipe (northern East European Platform): genetic models
The first results of mineralogical and geochemical studies of a unique xenolith of lithospheric mantle are presented illustrating the earlier non-described mineral association of quartz, Cr-pyrope and Cr-diopside. Structural and textural features of the sample suggest a joint formation of these minerals. The calculated P-T-parameters of the formation of Cr-diopside indicate the capture of xenolith from the depth interval ~ 95-105 km (31-35 kbar) corresponding to the stability field of coesite. This suggests that quartz in the studied xenolith can represent paramorphs after coesite. It was shown that quartz in this rock is not a product of postmagmatic processes. The transformation stage of the source lherzolite into garnet- and clinopyroxene-enriched rock/garnet pyroxenite as a result of exposure to a high-temperature silicate melt was reconstructed. Subsequent stages of the influence of metasomatic agents were identified by the presence of a negative Eu-anomaly in some garnet grains, which could result from the impact of subduction-related fluid and the enrichment of rock-forming minerals with light rare earth elements, Sr, Th, U, Nb and Ta as a consequence of fluid saturated with these incompatible elements. Several models for the formation of SiO2 phase (quartz/coesite) in association with high-chromium mantle minerals are considered including carbonatization of mantle peridotites/eclogites and melting of carbonate-containing eclogites at the stage of subduction and the impact of SiO2-enriched melt/fluid of subduction genesis with peridotites of the lithospheric mantle.
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Date submitted2023-03-16
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Date accepted2023-06-20
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Date published2023-07-19
Energy efficiency of the linear rack drive for sucker rod pumping units
- Authors:
- Oksana Yu. Ganzulenko
- Ani P. Petkova
At present, in order to increase oil production and reduce economic costs in the development of marginal fields, the development of a cluster method using compact mobile drives of sucker rod pumping units (SRPU) is relevant. The aim of the work is to analyze the ways to improve the energy efficiency of the SRPU by reducing the loss of mechanical and electrical energy, to select the most energy-efficient compact drive for the development of marginal fields in the cluster method, to carry out the kinematic and strength calculations of the drive of the selected size, to develop an adaptive control system for a group of drives in the cluster development of drillings. According to the results of the performed calculations, the linear rack-and-gear drive has the highest efficiency of the drive mechanism. The kinematic and strength calculations of a linear rack-and-gear drive with a stroke length of 1120 mm and a load of up to 8 tons are presented. It was shown that the usage of a direct torque control system and a kinetic energy storage system for the SRPU drive elements and a rod string is an effective means of reducing energy costs in oil production from marginal fields. The use of the developed system for storing and redistributing the potential energy of the rods between the SRPUs that lift oil made it possible to eliminate fluctuations in the power consumption, reduce the power peak value by three times, the peak value of the current consumed from the electric network by two times, and reduce losses in the input converter and cables by three times.
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Date submitted2022-04-07
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Date accepted2023-04-21
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Date published2023-08-28
Development of a new assessment system for the applicability of digital projects in the oil and gas sector
Digital transformation is one of the global trends that has covered most sectors of the economy and industry. For oil and gas companies, the introduction of digital technologies has become not just a trend, but one of the factors for ensuring competitiveness and maintaining a stable position in the market in a rapidly changing macro environment. At the same time, despite the positive effects achieved, digital transformation is a complex process from the point of view of implementation and is associated with high technological, financial, and economic risks. The work aims to develop and test a new system for evaluating the applicability of digital projects in the oil and gas sector. The research methodology includes the application of the Gartner curve, methods of expert assessments, and tools for assessing the economic efficiency of investment projects. The developed assessment system is based on a comprehensive accounting of four components: the level of digital maturity of the company; compliance of the implemented technology with the goals and objectives of the organization; the level of reliability of the implemented technology; the level of innovation of the implemented project. Particular attention is paid to the practical testing of the proposed methodology based on the evaluation of a digital project implemented by a Russian oil and gas company.
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Date submitted2022-04-08
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Date accepted2023-03-02
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Date published2023-04-25
Geochemical properties and transformation of the microelement composition of soils during the development of primary diamond deposits in Yakutia
Extraction of diamonds from primary deposits in Siberia is associated with the development of kimberlite pipes in challenging environmental conditions, accompanied by a complex impact on the environment. The article presents the results of monitoring the soil cover of the Nakyn kimberlite field in the Yakutia diamond province, which is affected by the facilities of the Nyurba Mining and Processing Division. Development of primary diamond deposits has a large-scale impact on the subsoil, topography, and soil cover: creation of the world's largest quarries, formation of dumps more than 100 m high, arrangement of extensive tailings, formation of solid and liquid industrial wastes of various chemical composition. The research is aimed at studying the spatial and temporal patterns of the technogenic impact on the soil cover, identifying the nature and level of transformation of the microelement composition of soils based on the analysis of the intra-profile and lateral distribution of mobile forms of trace elements. The study targets in 2007-2018 were zonal types of permafrost soils of northern taiga landscapes, cryozems, occupying 84 % of the total study area, which are characterized by biogenic accumulation of mobile forms of Ni, Mn, and Cd in the upper AO, A cr horizons, and Cr, Ni, Co, Mn, Cu in the suprapermafrost CR horizon. We found out that the contamination of the soil cover of the industrial site at the Nyurba Mining and Processing Division is of a multielement nature with local highly to very highly contaminated areas. Over a ten-year observation period, areas of stable soil contamination are formed, where the main pollutants are mobile forms of Mn, Zn, Ni. We suggest that against the background of a natural geochemical anomaly associated with trap and kimberlite magmatism, technogenic anomalies are formed in the surface horizons of soils. They are spatially linked to technogenically transformed landscapes. One of the sources of pollutants is the dispersion of the solid phase of dust emissions in the direction of the prevailing winds, which leads to the formation of soils with abnormally high contents of mobile forms of Mn, Zn, Ni.
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Date submitted2022-09-15
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Date accepted2022-11-17
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Date published2022-12-29
Comprehensive assessment of hydraulic fracturing technology efficiency for well construction during hydrocarbon production
The oil and gas industry has been an integral and fundamental sector of the Russian economy for the past few years. The main problems of this industry have traditionally been the deteriorating structure of oil reserves; depreciation of main assets; slowdown and decline in oil production. Recently these have been complicated by a number of new negative trends related to underinvestment, limited financial resources, deteriorating access to new equipment and technologies. The task of the research is to make a comprehensive assessment of hydraulic fracturing technology during well construction and to increase the recovery and intensification of hydrocarbons production. In this research, modeling techniques were used to assess the productivity of each fracture. Geophysical methods (seismic survey) were used to determine the geomechanical properties of the formation. Comprehensive assessment of hydraulic fracturing technology during well construction was carried out, which allowed to increase vertical permeability and unite disparate parts of the reservoir in practice, and to determine the development efficiency of the hydrocarbon field.
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Date submitted2022-01-31
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Date accepted2022-09-06
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Date published2022-11-10
Filtration studies on cores and sand packed tubes from the Urengoy field for determining the efficiency of simultaneous water and gas injection on formation when extracting condensate from low-pressure reservoirs and oil from oil rims
- Authors:
- Nikolay A. Drozdov
Oil rims as well as gas condensate reservoirs of Russia's largest Urengoy field are developed by depletion drive without formation pressure maintenance, which has led to serious complications in production of oil, gas and condensate. In addition, field development by depletion drive results in low values of oil and condensate recovery. These problems are also relevant for other oil and gas condensate fields. One of the possible solutions is simultaneous water and gas injection. Rational values of gas content in the mixture for affecting gas condensate fields and oil rims of oil and gas condensate fields should be selected using the data of filtration studies on core models. The article presents the results of filtration experiments on displacement of condensate and oil by water, gas and water-gas mixtures when simulating the conditions of the Urengoy field. Simultaneous water and gas injection showed good results in the experiments on displacement of condensate, residual gas and oil. It has been ascertained that water-gas mixtures with low gas content (10-20 %) have a better oil-displacement ability (9.5-13.5 % higher) than water. An experiment using a composite linear reservoir model from cemented core material, as regards the main characteristics of oil displacement, gave the same results as filtration experiments with sand packed tubes and demonstrated a high efficiency of simultaneous water and gas injection as a method of increasing oil recovery at oil and gas condensate fields.
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Date submitted2022-05-04
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Date accepted2022-06-15
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Date published2022-07-26
Prospecting models of primary diamond deposits of the north of the East European Platform
As a result of a comprehensive study of the geological structure and diamond presense of the northern part of the East European Platform, generalization of the data accumulated by various organizations in the USSR, the Russian Federation, and other states, three main prospecting models of primary diamond deposits have been identified and characterized: Karelian, Finnish, and Arkhangelsk. Geological, structural, mineralogical, and petrographic criteria of local prediction, as well as the features of the response of kimberlite and lamproite bodies in dispersion haloes and geophysical fields, are considered using known examples, including data on the developed M.V.Lomonosov and V.P.Grib mines. It is shown that the most complicated prospecting environments occur in the covered areas of the Russian Plate, where, in some cases, the primary diamond-bearing rocks are similar in their petrophysical properties to the host formations. The buried dispersion haloes of kimberlite minerals in the continental Carboniferous and Quaternary deposits are traced at a short distance from the sources. Differences in the prospecting features of magnesian (Lomonosov mine) and ferromagnesian (Grib mine) kimberlites are also shown. Conclusions about the diamond potential of the model objects of various types are given in this paper.
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Date submitted2022-01-28
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Date accepted2022-04-26
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Date published2022-07-26
On the presence of the postmagmatic stage of diamond formation in kimberlites
- Authors:
- Sergey K. Simakov
- Yuri B. Stegnitskiy
On nowadays multiphase and the facies heterogeneity of the formations are distinguished at the study of kimberlite pipes. Most researchers associate the formation of diamonds only with the mantle source. To date, satellite minerals with specific compositions associated with kimberlite diamonds have been identified as deep mantle diamond association. They are extracted from the concentrate of the kimberlites heavy fraction and may reflect the diamond grade of the pipe. For some minerals in the diamond association, however, they can not be reliable. Some researchers also revealed shallow diamond associations, related to the formation of serpentine, calcite, apatite, and phlogopite. There is recent data on the formation of diamonds in rocks of the oceanic crust. In the last years microdiamonds were identified in chromites of the oceanic crust in association with antigorite formed at 350-650 °C and 0.1-1.6 GPa. As a result, the authors established a postmagmatic kimberlitic stage of diamond formation associated with secondary mineral associations based on the experimental and mineralogical data for the conditions of the shallow upper mantle and crust. Mineralogical and petrographic studies of Angolan kimberlite pipe show that antigorite is the indicator mineral of this stage.
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Date submitted2021-03-31
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Date accepted2021-09-29
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Date published2021-10-21
Methodology of modeling nonlinear geomechanical processes in blocky and layered rock masses on models made of equivalent materials
- Authors:
- Boris Yu. Zuev
The research purpose is to develop a methodology that increases the reliability of reproduction and research on models made of equivalent materials of complex nonlinear processes of deformation and destruction of structured rock masses under the influence of underground mining operations to provide a more accurate prediction of the occurrence of dangerous phenomena and assessment of their consequences. New approaches to similarity criterion based on the fundamental laws of thermodynamics; new types of equivalent materials that meet these criteria; systems for the formation of various initial and boundary conditions regulated by specially developed computer programs; new technical means for more reliable determination of stresses in models; new methods for solving inverse geomechanical problems in the absence of the necessary initial field data have been developed. Using the developed methodology, a number of complex nonlinear problems have been solved related to estimates of the oscillatory nature of changes in the bearing pressure during dynamic roof collapse processes; ranges of changes in the frequency of processes during deformation and destruction of rock mass elements, ranges of changes in their accelerations; parameters of shifts with a violation of the continuity of the rock mass under the influence of mining: secant cracks, delaminations, gaping voids, accounting for which is necessary to assess the danger of the formation of continuous water supply canals in the water-protection layer.
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Date submitted2021-01-19
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Date accepted2021-07-27
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Date published2021-10-21
Geological and structural characteristics of deep-level rock mass of the Udachnaya pipe deposit
- Authors:
- Evgenii V. Serebryakov
- Andrei S. Gladkov
For hard rock massifs, structural disturbance is a key indicator of mining structure stability. The presence of intersecting structural elements in the massif reduces rock strength and leads to formation of potential collapse structures. In addition to that, disjunctive deformations that penetrate rock strata serve as channels for fluid migration and connect aquifers into a single system. It was established that the largest of them –faults of east-northeastern, northeastern and northwestern directions – form the kimberlite-bearing junction of the Udachnaya pipe. These faults represent zones of increased fracturing, brecciation and tectonic foliation, distinguished from adjacent areas by increased destruction of the rock mass. Specifics of tectonic fracture distribution within structural and lithological domains are determined by the presence of multidirectional prevailing systems of tectonic fracturing, as well as by differences in their quantitative characteristics. With some exceptions, the main systems form a diagonal network of fractures (northeastern – northwestern orientation), which is typical for larger structural forms – faults. Despite the differences in dip orientation of the systems, most of them correspond to identified directions, which is typical for both kimberlites and sedimentary strata. Overall disturbance of the massif, expressed in terms of elementary block volume, reaches its peak in the western ore body. For such type of deposits, friction properties of fracture structures have average values. Consideration of geological and structural data in the design and development of new levels of the deposit will allow to maintain the necessary balance between efficiency and safety of performed operations.
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Date submitted2019-12-20
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Date accepted2020-09-01
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Date published2020-10-08
Features of the underground storages construction in depleted oil and gas condensate fields
The paper considers the features of the underground storages (US) construction in depleted oil and gas condensate fields (DOGCFs). The requirements for the structure of the formation, corresponding to the parameters of the object for possible US creation are presented. The influence of geological, hydrogeological, mining and technical rock formation conditions on the reliability and tightness of underground storages, including underground gas storages, has been evaluated. The necessary conditions for the US design are analyzed at the example of the Ach-Su oil and gas condensate field, in the presence of a well-explored trap with acceptable parameters for the construction of an underground storage. An important aspect is the geological conditions that meet the criteria for selecting the object: the required structure, the absence of fracturing faults, high reservoir properties of the formation, a sufficient volume of the deposit for the storage. Geological conditions lay the basis for determining the individual characteristics of the US construction technology at each DOGCF. The refined results for the current gas-saturated pore volume and the rate of pressure drop in the formation are presented, which makes it possible to select improved technological indicators in the course of operation of the created US. In order to select the optimal option for the design and construction of the US, the results of economic and geological scenarios analysis were studied concurrently with the capabilities of the technological operation of the object and transport system, which can ensure the maximum daily production of the storage.
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Date submitted2019-03-21
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Date accepted2019-05-05
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Date published2019-08-23
Stimulation of the Drilling Process with the Top Driven Screw Downhole Motor
- Authors:
- S. L. Simonyants
- M. Al Taee
Paper considers application of the top driven screw downhole motor during drilling of directional wells. The advantages and disadvantages of the rotation-sliding technology with implementation of top drive together with screw downhole motor are shown. It has been proven that the use of a screw downhole motor with simultaneous rotation of drilling pipes using the drilling rig's top drive allows increasing the bit rotation frequency without additional loading of the drilling string. Field data for the work out of one-type PDC bits in identical geological and technical conditions with different types of drives during the construction of three directed wells at the Rumaila oil field of the Republic of Iraq were obtained. A regular increase in the mechanical penetration rate, which is explained by an increase in the bit rotation frequency, has been proved. According to the data obtained, a comparative analysis of the drilling indices was carried out, as a result of which the feasibility of joint use of top power drive with screw downhole motor at drilling oil and gas wells was proved.
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Date submitted2016-11-11
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Date accepted2017-01-21
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Date published2017-04-14
Conducting lithospheric heterogeneities as a criterion of predictive assessment for promising diamond areas (on the example of Siberian kimberlite province)
- Authors:
- E. V. Pospeeva
Results of magnetotelluric tests, carried out in Siberian kimberlite province, are examined from the viewpoint of structural control over location of kimberlite fields and bunches of kimberlite pipes. It is demonstrated that the key factors controlling occurrence of kimberlite magmatism are: deep systems of rift-driven fractures; areas of their intersection within high-ohmic blocks of Earth crust; conducting permeable areas, located at the intersections of deep faults. Various-rank objects of kimberlite magmatism are characterized by a certain combination of geoelectric heterogeneities, differing in resistance, lateral sizes and depth. The province is situated within the boundaries, limited by isolines 180-220 km of current asthenosphere; kimberlite areas – within the contours of high-resistance regional heterogeneities. Fields and bunches of kimberlite pipes are concentrated within boundaries of conducting subvertical zones. These factors can be used as criteria of predictive assessment for promising diamond areas of the ancient platforms.
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Date submitted2014-12-30
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Date accepted2015-02-03
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Date published2015-12-25
Open mining technique for unconventional mineral deposits
- Authors:
- G. A. Kholodnyakov
- K. R. Argimbaev
Nowadays the majority of deposits are successfully exploiting by mining enterprises with the help of traditional excavation and loading equipment. Typically, metals, construction materials, etc. are mined and extracted on these deposits, but modern society is progressing and producing new requirements to metals properties for creating a new type of equipment. The metals with new properties are located in unconventional areas: either in technogenic deposits (overburden dumps, tailings, etc.) or in hard-to-get natural formations. Technogenic mines, being a tailing of Kachkanarsky mining and processing plant, are referred to such unique deposits, which have expensive metals (scandium, gallium, strontium, titanium), as well as the natural deposit – rhenium deposit, located in the crater of an active volcano. Potentialities of open mining in the largest rhenium deposit with complex environmental occurrence have been analyzed in the paper. Temperature measurement results of adjacent strata and a temperature scheme of the host rocks on a separate site and the entire field have been presented. An open mining technique for a primary mining area as well as perspective methods of rock preparation for excavation, applicable to this particular deposit, has been considered.
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Date submitted2014-11-27
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Date accepted2015-01-15
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Date published2015-10-26
Socio-economic potential of large-scale projects to develop offshore oil and gas: risks and stakeholder expectations
- Authors:
- A. E. Cherepovitsyn
The development of the Arctic shelf is a strategic long-term objective of the energy development of the Russian Federation. At the present time, resource and economic potential of offshore oil and gas development projects is huge. However, it is constrained by the complexity of developing offshore oil and gas resources due to climatic, geological and technological conditions. In addition, the current unstable situation with world oil prices is also a constraint on largescale involvement in the industrial development of offshore oil and gas resources. The aim of the research is to determine socioeconomic potential of large-scale projects to develop oil fields in the Arctic shelf of Russia. The article presents the peculiarities of developing offshore fields, which are characterized by severe climatic conditions, high environmental risks, unique technological solutions, lack of infrastructure in coastal areas. A comparative analysis of projects to develop land and shelf is performed. The regional authorities’ and businesses capability of implementing large-scale projects to develop offshore fields on economic, social and environmental criteria is identified. The positive and negative effects of socio-economic development of the territory implementing projects of hydrocarbon field development are evaluated. A schematic diagram of the socio-economic potential of hydrocarbon resources development projects reflecting the opportunities and risks of such projects from the perspective of key stakeholders is developed. A set of strategic objectives to successfully implement projects in the Arctic shelf of Russia are proposed. The findings of the research can be used by the departments of energy, industry and mineral resources in the preparation of long-term strategic development programs for the oil and gas industry.
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Date submitted2014-07-21
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Date accepted2014-09-19
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Date published2014-12-22
Preliminary preparation of oil for primary processing
Oil supplied for primary processing always undergoes preliminary preparation, the purpose of which is to eliminate the harmful effect of water and salt contained in the oil. It is thought that corrosion of the equipment is connected mainly with chlorides of magnesium and calcium, which are subjected to hydrolysis with the formation of hydrochloric acid. Under the influence of hydrochloric acid the destruction (corrosion) of metal equipment at technological plants occurs (especially refrigerating-condensing and heatexchange equipment, furnaces of rectification units etc.). The authors of the article, on the basis of thermodynamic calculations, provide their point of view on this process and give a methodology by which the process of preliminary oil dehydration and desalting can be controlled. The thermodynamic calculations executed for standard conditions on the basis of refer-enced data confirm a high probability of chemical interaction of iron with hydrogen ions, hy-drogen sulphide and especially with carbonic acid. This testifies to high activity of the carbon dioxide dissolved in water and the impossibility of hydrolysis of ions of magnesium, calcium and iron. The calculations show that only the hydrolysis of magnesium chloride is possible tak-ing into account the ionic composition of the water phase in the oil. It should be noted that the presence of ions of chlorine shifts the iron potential in a nega-tive direction and increases the speed of corrosion of petrochemical equipment. The solution of this problem is in the development of modern methods of crude oil dehydration and desalting. It is also, however, in an intensification of the processes of mixing water-oil emulsions with wash-ing water by using various physical fields (for example, ultrasound) and creating new effective mixing devices on the basis of them.
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Date submitted2013-07-22
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Date accepted2013-09-24
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Date published2014-03-17
Contemporary Problems of salvaging drill cuttings on the Western Siberia oilfields of the final stage of development
- Authors:
- V. V. Katsilo
The article deals with the problem of disposing of industrial and technological drilling wastes due to the application of salt biopolymer drilling fluids for extraction of residual oilfields of Western Siberia, which are at an final stage of development using the technology of directional drilling. The problem of disposal of drilling waste in the oilfields of the final stage of development is proposed to solve through the introduction of protective functions of the complex engineering activities, including, the development of waterproofing layer of clay cuttings, which is formed by drilling the top of the production casing, for different host rock cuttings.
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Date submitted2009-09-01
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Date accepted2009-11-09
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Date published2010-06-25
Thermal, power and economic parameters of innovative technology of development of nearsurface geothermal deposits
- Authors:
- E. I. Boguslavskiy
Deficiency of organic fuel and necessity of protection of environment cause growth of rates of development practically inexhaustible, everywhere widespread and ecologically pure geothermal resources. For needs of a heat supply especially actively developing innovative technology of development of near-surface geothermal resources has great value. Operative mining of the production schedules containing optimum parametres and indicators PSGT is necessary for designing and building of near-surface systems of a geothermal heat supply (PSGT). The imitating economic-mathematical model is developed, the algorithm and the program of their optimisation are created. Computer calculations for a wide range of natural, power and economic conditions are carried out. Key parametres and indicators PSGT are defined. Their optimum values for a heat supply of local consumers (apartment houses) in the conditions of the Yaroslavl area are recommended.
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Date submitted2009-07-12
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Date accepted2009-09-16
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Date published2010-04-22
Numerical assessment of stress-strain field in vicinity of large open pit mine taking into account geomechanical, geological and mining factors
The results of modeling of rock mass stress state in the vicinity of large open pit mine using finite-elements method are represented. The model allows to take into account the influence of large-scale fractures. The initiation of boundary conditions is based on the results of determination of stress parameters in situ. The locations of risk areas near the slope are defined.
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Date submitted2009-07-25
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Date accepted2009-09-09
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Date published2010-04-22
The use of data on stress-strain state of rock mass in solutions of mining-and-technical tasks on the example of the Tishin ore mine
The Permion State Technical University and ASE «VNIItsvetmet» have carried out in situ measurements of stress-strain state at the Tishinsky lead-zinc ore deposit. Measurements and interpretation of deformations and stresses caused by excavation were used. Complex of researches made it possible to solve some important problems for safeguarding effective and secure ore production ore on deep level.
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Date submitted2008-11-15
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Date accepted2009-01-11
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Date published2009-12-11
Economic mechanism of forming of hydrocarbon fields special fund
- Authors:
- A. E. Cherepovitsyn
- A. V. Radko
Factors and presuppositions of forming of special fund of fields are determined. Scheme of functioning of special fund of fields, inclusive elements of production share and privileged taxation are proposed. Economic efficiency of special funds of oil and gas fields’ development are defined.
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Date submitted2008-10-20
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Date accepted2008-12-22
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Date published2009-12-11
Analytical continuation of geophysical fields by continued fractions method
- Authors:
- K. M. Ermokhin
The most close to reality geophysical field description is the approximation of the fraction-rational type. In this case the presence of poles in the lower half space corresponds adequately to the denominator zeros. This article contains the theory and algorithm of realization of this conception. The proposed method is called – Continued Fraction Continuation Method.
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Date submitted2008-10-21
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Date accepted2008-12-10
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Date published2009-12-11
Prediction and prospecting types of reflection of buried kimberlite fields in terrigenous diamond-bearing rocks
- Authors:
- V. N. Ustinov
On the basis of complex of lithologic-stratigraphic, mineralogical, facial-dynamic, paleogeomorphologic and morphogenetic features of post-kimberlitic terrigenous diamond-bearing rocks and reconstructed synchronous relief three prediction and prospecting types of reflection of buried kimberlite fields are distinguished. It is shown that ranging of diamondiferous territories to various types enables to direct exploration works to discovery of diamond deposits of the certain origin and makes possible to select proper prospecting technique. With the use of suggested criteria of research of promising territories the evaluation of diamond presence in the industrial regions of the Siberian, East-European and African-Arabian platforms is carried out.
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Date submitted2008-10-22
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Date accepted2008-12-14
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Date published2009-12-11
Peculiarities of structure and comparative analysis of oil-and-gas basins in the Pacific segment of lithosphere
- Authors:
- V. B. Archegov
Comparative analysis was carried out for oil-and-gas-bearing basins of young and oldland platforms of the Pacific segment. Previously the same kind of analysis had been realized for the Atlantic segment of lithosphere. Obtained results confirm the unique geological structure and oil-and-gas capacity of Siberian platform, by these features it differs from all other cratons in the whole world.
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Date submitted1952-07-06
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Date accepted1952-09-29
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Date published1953-01-01
On the issue of permafrost formation and degradation of permafrost in non-stationary temperature fields
- Authors:
- A. S. Ter-Pogosyan
The theoretical calculation of the movement of the permafrost boundary inside the soil under the influence of temperature changes on the surface is of great scientific importance in permafrost science: a whole range of issues of the dynamics of the permafrost process depends on its solution, including the correct scientific analysis of the current state of the permafrost zone, its changes (degradation and onset) under the influence of climate change, the correct definition of the role and place of the thermal factor in a number of geological and other factors of permafrost formation, etc. However, this calculation can also have important practical significance for a number of problems of industrial development of the permafrost area, for example, for establishing a rational thermal regime for the currently empirically used methods of artificial thawing of frozen deposits, for industrial construction in the permafrost zone, etc. The problem of permafrost penetration into the soil or permafrost thawing is similar to the problem of propagation of the solidification boundary into the molten mass. Unfortunately, the latter can be solved exactly only under stationary conditions, with the initial temperature of the liquid being the same everywhere and a constant temperature given on the surface, taken below the freezing point.