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Date submitted2023-05-21
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Date accepted2024-05-02
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Date published2024-08-26
Assessment of the influence of lithofacies conditions on the distribution of organic carbon in the Upper Devonian “Domanik” deposits of the Timan-Pechora Province
The study of high-carbon formations was instigated both by the decreasing raw material base of oil as a result of its extraction, and by the progress in development of low-permeability shale strata, primarily in the USA, Australia, and China. The most valuable formations occur in traditional hydrocarbon production areas – the West Siberian, Volga-Ural and Timan-Pechora, North Pre-Caucasian and Lena-Tunguska oil and gas provinces. Specific features of the Late Devonian-Early Carboniferous high-carbon formation occurring in the eastern marginal part of the East European Platform are: heterogeneous section due to intense progradation of the carbonate platform from west to east; succession of lithofacies environments that determined the unevenness of the primary accumulation and secondary distribution of organic matter (OM); possible migration or preservation in the source strata during the subsidence stages of the moving parts of bitumides, which determined the prospects for oil and gas potential. The distribution pattern of the present OM content was investigated depending on lithofacies conditions and lithological composition of rocks in the “Domanik type” Upper Devonian-Tournaisian deposits in the Timan-Pechora Province (TPP), its transformation degree to bring it to the initial content of organic carbon and further estimation of the share of stored “mobile oil” in oil and gas source formation. The study was based on the analysis of the data set on organic carbon content in core samples and natural exposures in the Ukhta Region in the Domanik-Tournaisian part of the section including more than 5,000 determinations presented in reports and publications of VNIGRI and VNIGNI and supplemented by pyrolytic and bituminological analyses associated with the results of microtomographic, macro- and lithological studies and descriptions of thin sections made at the Saint Petersburg Mining University. For each tectonic zone of the TPP within the investigated high-carbon intervals, the content of total volumes of organic carbon was determined. The data obtained allow estimating the residual mass of mobile bitumoids in a low-permeability matrix of the high-carbon formation.
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Date submitted2023-08-14
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Date accepted2023-12-27
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Date published2024-12-25
Modelling of compositional gradient for reservoir fluid in a gas condensate deposit with account for scattered liquid hydrocarbons
In oil and gas reservoirs with significant hydrocarbon columns the dependency of the initial hydrocarbon composition on depth – the compositional gradient – is an important factor in assessing the initial amounts of components in place, the position of the gas-oil contact, and variations of fluid properties throughout the reservoir volume. Known models of the compositional gradient are based on thermodynamic relations assuming a quasi-equilibrium state of a multi-component hydrodynamically connected hydrocarbon system in the gravity field, taking into account the influence of the natural geothermal gradient. The corresponding algorithms allow for calculation of changes in pressure and hydrocarbon fluid composition with depth, including determination of the gas-oil contact (GOC) position. Above and below the GOC, the fluid state is considered single-phase. Many oil-gas-condensate reservoirs typically have a small initial fraction of the liquid hydrocarbon phase (LHC) – scattered oil – within the gas-saturated part of the reservoir. To account for this phenomenon, a special modification of the thermodynamic model has been proposed, and an algorithm for calculating the compositional gradient in a gas condensate reservoir with the presence of LHC has been implemented. Simulation cases modelling the characteristic compositions and conditions of three real oil-gas-condensate fields are considered. The results of the calculations using the proposed algorithm show peculiarities of variations of the LHC content and its impact on the distribution of gas condensate mixture composition with depth. The presence of LHC leads to an increase in the level and possible change in the type of the fluid contact. The character of the LHC fraction dependency on depth can be different and is governed by the dissolution of light components in the saturated liquid phase. The composition of the LHC in the gas condensate part of the reservoir changes with depth differently than in the oil zone, where the liquid phase is undersaturated with light hydrocarbons. The results of the study are significant for assessing initial amounts of hydrocarbon components and potential efficiency of their recovery in gas condensate and oil-gas-condensate reservoirs with large hydrocarbon columns.
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Date submitted2020-05-13
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Date accepted2020-06-24
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Date published2020-10-08
Barriers to implementation of hydrogen initiatives in the context of global energy sustainable development
Modern trends in the global energy market linked to the Sustainable Development Goals often lead to the adoption of political decisions with little basis in fact. Stepping up the development of renewable energy sources is an economically questionable but necessary step in terms of its social and ecological effects. However, subsequent development of hydrogen infrastructure is, at the very least, a dangerous initiative. In connection with mentioned above, an attempt to examine hydrogen by conducting an integral assessment of its characteristics has been made in this article. As a result of the research conducted, the following conclusions concerning the potential of the widespread implementation of hydrogen in the power generation sector have been made: as a chemical element, it harms steel structures, which significantly impedes the selection of suitable materials; its physical and volume characteristics decrease the general efficiency of the energy system compared to similar hydrocarbon solutions; the hydrogen economy does not have the necessary foundation in terms of both physical infrastructure and market regulation mechanisms; the emergence of widely available hydrogen poses a danger for society due to its high combustibility. Following the results of the study, it was concluded that the existing pilot hydrogen projects are positive yet not scalable solutions for the power generation sector due to the lack of available technologies to construct large-scale and geographically distributed infrastructure and adequate international system of industry regulation. Thus, under current conditions, the risks of implementing such projects considerably exceed their potential ecological benefits.
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Date submitted2019-07-11
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Date accepted2019-08-25
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Date published2019-12-24
Improving the efficiency of using resource base of liquid hydrocarbons in Jurassic deposits of Western Siberia
Under conditions of the same type of oil deposits with hard-to-recover reserves in Jurassic terrigenous reservoirs of the West Siberian oil and gas province, a study was made about the influence of the geological structure features of objects and water flooding technologies on the response degree of production wells to water injection. Response degree of the wells was determined by analyzing the time series of production rates and injection volumes of injection wells with the calculation of inter-correlation function (ICF) values. It was believed that with ICF values in a given injection period of more than 0.5, production well responds to the injection. Factors that have a prevailing effect on water flooding success have been identified. Among them: effective oil-saturated thickness of the formation in production wells; relative amplitude of the self polarization of the formation in both production and injection wells; grittiness coefficient of the formation in injection wells; monthly volume of water injection and distance between wells. Methodological approach is proposed based on the application of the proposed empirical parameter of water flooding success, which involves the use of indirect data in conditions of limited information about the processes occurring in the formation at justification and selection of production wells for transferring them to injection during focal flooding; drilling of additional production and injection wells – compaction of the well grid; shutdown of injection and production wells; use of a transit wells stock; use of cyclic, non-stationary flooding in order to change the direction of filtration flows; determining the design of dual-purpose L-shaped wells (determining length of the horizontal part); limitation of flow rate in highly flooded wells with a high degree of interaction; determination of decompression zones (without injection of indicators), stagnant zones for drilling sidetracks, improving the location of production and injection wells, transferring wells from other horizons; choosing the purpose of the wells during implementation of the selective water flooding system in order to increase the efficiency of using the resource base of liquid hydrocarbons.
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Date submitted2015-10-17
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Date accepted2015-12-19
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Date published2016-08-22
Improving the retention of minerals in the course of separating monolith from bedrock with the use of gas generator cartridges
- Authors:
- G. P. Paramonov
- V. N. Kovalevskii
- Peter Mozer
Results are presented on the effect of firing rate on pressure pulse in charge camera and fracture stress during spalling. Results are presented of comparative calculations using the equations of autocatalytic reactions of firing rates and escape of reaction products for the system of sodium chlorate - polythene (propylene) in pipe shape. Dependences are obtained of firing rate on concentration of gas generating mixture, its density, components size distribution and cartridge case size. Experimental and computational data were used to consider the conditions of firing turning into explosion for compositions based on sodium chlorate and hydrocarbons in layered and powdered systems. The relation is retrieved between the technological parameters of mining activities (blast hole to blast hole distance, blast hole diameter, depth of cartridge placement) and specific cartridge consumption along the spalling line with gas generators going off.
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Date submitted2015-08-17
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Date accepted2015-10-12
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Date published2016-04-22
Isolation of promising areas to drill for unconventional hydrocarbons petrikovskih sediments Davydovskogo deposit Pripyat Trough
- Authors:
- E.I. Shevelev
Pripyat Trough is the only oil basin in the territory of the Republic of Belarus. Mining is carried out within the basin for 50 years. During this time, the proportion of active stocks decreased significantly, while the share of hard-to-inventories increased. Therefore, due to the depletion of traditional reserves, urgent problem arises in the study and production of unconventional hydrocarbon traps. To this type of traps are Petrikov deposits Davydov field. These deposits have low permeability and capacitive properties, but at the same time in a number of wells in the test sediment in Colon yielded commercial oil inflows. Some of the well in a certain period of development led oil from Petrikov deposits. In similar deposits Rechitsa field yielded commercial oil inflows in drilling horizontal wells with hydraulic fracturing. Until recently, the reservoir Petrikov deposits was listed among the off-balance sheet reserves after drilling – reserves transferred to the balance of C1. Therefore, the input to the development of stranded there is a need to identify the most promising area for drilling horizontal wells, followed by hydraulic fracturing. To perform this work was carried out pointwise interpretation of GIS for all wells Davydov field, the results of which built the geological and petrophysical model of the deposit. Also, the analysis of core samples, the results of drilling. Produced dismemberment Petrikov deposits on two subhorizon on the results of the interpretation of GIS and well logs. The outcome of the work performed is a recommended site for drilling.
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Date submitted2014-12-19
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Date accepted2015-02-27
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Date published2015-12-25
Geological and mathematical model of secondary sulphidisation zone polarizability as a function of oil and gas deposit depth
- Authors:
- O. F. Putikov
- S. A. Ivanov
The differential-normalized method of electrical exploration (DNME), by means of polarization study of the secondary sulphidation zone (depth ~ 0,4-0,6 km), allows making conclusion about existence and parameters of an oil and gas deposit (depth up to ~ 2-5 km). The approximate solution of the system of nonlinear differential equations in partial derivatives for concentration of sulfur-hydrogen and pyrite (polarizability) as the function of oil-gas deposit depth has been received. The results are confirmed by experimental investigations in the North Sea.
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Date submitted2014-11-01
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Date accepted2015-01-25
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Date published2015-10-26
Application of the geoelectrochemical method for prospecting of oil and gas deposits in the Barents and Kara seas
- Authors:
- M. A. Kholmyanskii
- S. P. Pavlov
- O. F. Putikov
The use of the geoelectrochemical method of ion-selective electrodes for continuous recording of hydrocarbon micro-components – heavy metals – during the vessel movement to search for oil and gas deposits on the shelf is justified theoretically and experimentally. The existence of «jet» halos in the water column above the shelf oil and gas deposits is discovered experimentally and the method of geoelectrochemical ion-selective electrodes as well as the developed instrumentation for recording these halos is described. The application of a new geoelectrochemical method for prospecting in motion (without sampling) both structural and non-structural oil and gas deposits on the shelf is justified.
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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 submitted2008-10-13
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Date accepted2008-12-28
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Date published2009-12-11
Ore-forming hydrothermal solutions and gas hydrate formation in the ocean
- Authors:
- S. M. Sudarikov
- S. S. Filatova
Geological and tectonic settings and thermobaric characteristics of hydrothermal activity are confronted with those of gas hydrate formation. Hydrocarbon concentrations and isotopic composition in hydrothermal fluids of mid-ocean ridges with different thickness of sediment cover and marginal oceanic basins are compared. The possible influence of rising thermal fluids on gas hydrate accumulations was analyzed and examples of hydrate formation linked with hydrothermal process are given.
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Date submitted2008-10-13
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Date accepted2008-12-15
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Date published2009-12-11
A complex of gravi-, magneto-, electroprospecting аnd geoelectrochemical methods for local prediction and prospecting for hydrocarbon deposits
It is proposed to use interpretational spatial distributions of effective parameters of the medium under investigation instead of measured fields in the process of comprehensive prediction-prospecting investigations. There are used effectively: effective density, effective magnetization, intensity of probable sources of geochemical anomalies.