The paper presents engineering solutions utilized in directional drilling as well as the impact they have on construction of underwater passages. This is exemplified by an accident development scenario of passing through gravel and cobble soils. Following the model of stress-strain state of soils composing the wellbore and based on fluid dynamics model pertaining to drillingmud filtration, potentially hazardous process failures have been analyzed.
This paper addresses the issue of selecting a rock cutting tool to ream a pilot bore of an underwater passage as applicable to soil physics and mechanics and reaming techniques. Engineering challenges arising from the use of various cutting tools for reaming are also highlighted.
At the present time, the gas field is a complex system, which includes various subsystems such as: separator, pipelines, wells and reservoir. One of the actual problem of the field operational management is a gas-condensate wells regime planning. The objective is to find by iterations a wellhead pressure that will provide require production plan and will keep stabilize regime for each well.As an approach for this aim authors proposed the Levenberg - Marquardt algorithm which will describe in this article.
The article describes tests and the results of the integrated exploration of formation hydrocarbon system gas-condensate characteristics of wells of the Achimov deposits of the Urengoyskoe feld, situated in the area 2A of the experimental program, concerning with the depletion ofthe reservoir energy, taking into account their unique geological and physical parameters.
The article reviews consistent pattern of thickness variation of Berriasian-Lower Valanginian in West Siberia. The paper specifies expansion zones related to palaeodepressions of Late Cimmerian deposition. The presence of such depressions became crucial in perception of Neocomian sedimentation trends. It resulted in justification of Achimov formation variative ages (deep-sea Neocomian sands) and reiterated validity of Neocomian structure clinoform model for West Siberia.
Despite longstanding debates on origin of hydrocarbons, theories keep coming. The author of the paper presents his view on the role of microorganisms in petroleum formation with respect to deep planetary degassing. Not only does such approach somewhat help to compensate for weak points and shortcomings of both organic and inorganic theories, but It also fills their gaps and enables to draw one’s own conclusion. Interesting microbiology studies of recent years have allowed geologists to differently tackle the issues of elementary life forms, their relation with development of Earth’s atmosphere and lithosphere and potential impact on formation of hydrocarbons.
This paper gives the very first description of the reservoir void spaces of the Senonian epoch, belonging to the area of Nadym, Pur and Tazovskiy in West Siberia. The research is based on the core analysis accomplished with such techniques as light microscopy, X-ray microtomography, and mercury porosimetry. The study has also employed the data received with volumetric and static analyzer of specific surface area and porosity of the samples. It has been found that fracture capacity amounts to 1/30 of total porosity, and flow channels are sized to a nanoscale, which depends on the form of silica prevailing in the formation.
The paper presents the findings of a research study of BS102+3 reservoir geology, including classification of well logs based on thorough correlation between stratum thicknesses and their quantities. Hydrodynamic study has allowed us to confirm the occurrence of faults, review their impact on connectivity across BS102+3 reservoir and reveal potentially bypassed areas for further investigation, completion and enhancement of oil recovery factor. It has been found that distribution of facies is related to NS tectonic deformation.
Most oilfields in the Republic of Tatarstan are currently nearly depleted. Assets of each oil and gas production facility include wells which are considered noncommercial due to complex geology and low reserves. Preparation of reserves and their development is a current challenge for geologists. This paper addresses application of conceptual geologic model of Bobrikovskian formation in Sirenevskoye oilfield to estimate reserves and further evaluate hydrodynamic model. Recreation of depositional environment has been achieved through lithofacies analysis.
High requirements to the quality and productivity of marine seismic exploration determine the modern technology of field observations.The acquaintance of Russian survey geophysicists with the materials of the international geophysical conference is of some interest, since The reports reflect the development trends in marine seismictechnology, which illustrate the efficiency and good prospects for the future and can be useful to domestic marine seismic surveys.
The study discusses the experience of Gazprom Neft Shelf LLC in implementing stationary tracing monitoring technology for horizontal wells in the Prirazlomnoye oilfield. The paper explores the technology of inflow profiling based on the data from intelligent inflow tracers installed in completion strings of production wells in the Prirazlomnoye oilfield.
In this article were analyzed causes of failures the gas pumping unit equipment of compressor stations and statistics of theirs’s failures in the course of 10 years. Key causes responsible for failures of sleeve bearings which fix the position of the turbine rotor shaft and ensure minimal clearance in the inflow section have been revealed. An original mathematical model of the basic components in a gas pumping unit has been devised for the purpose of identifying faults happening in the thrust section of the sleeve bearings based on diagnostic parameters. This has made it possible to ascertain the working condition of the sleeve bearings by the change in their rigidity in the oscillating model of the gas pumping unit key elements.
The paper explores the new technique of measuring drainage capillary pressure curves using digital microtomography imaging of porous media. Analysis of drainage curves is based on simulation experiments of displacement of one fluid in the pore volume with the other. Computational grid is represented by binary microtomography imaging of sandstone. Mathematical tool used for computation is the lattice Boltzmann method. Calculated curves have been successfully correlated with experimental data. It has been shown that the flowpatterns, used in simulation experiments, have revealed peculiar propagation in directions different from flowing pressure gradient, including opposite directions.
The paper explores impact of fault conductivity on development dynamics of oil reservoir under depletion drive. It also presents comparison of sealing faults and capillary barriers. In both cases, the fault is identified both by the presence of amplitude shifts and by the difference in water-oil contact levels in the adjacent sections of the deposit. The study is conducted on a 3D flow simulation model of a hypothetical hydrocarbon deposit based on the initial data for one of the fields in West Siberia. The results of the simulation show that erroneous estimates of the fault conductivity may lead to an incorrect choice of the field development system and the sequence of wells drilled, which significantly affects production performance and recovery of reserves.
PJSC Tatneft has been implementing a program for production optimization and reducing its own costs. Cutting down the costs incurred in operation of above ground oil field equipment is one of the key priorities within the framework of the above mentioned program. This article discusses the upgrading of pump unit shaft seals for the pumping of produced liquid.
The paper explores ESP shaft failures, occurring in difficult wells. It also presents protection technology for downhole pumping equipment to prevent failures.
This article presents the results of the analysis formed the base data of the filtration-capacitive properties (FCP) of carbonate reservoirs.Collected indicators of FCP defined on the whole complex of methods: laboratory studies ofcore samples, well logging, hydrodynamic well survey, lifetime data.Proposed assessment field classification of carbonate reservoirs, which allows to evaluate the predominant type of permeability that provides a flow. The purpose of the proposed valuation and commercial classification is to complement existing classifications, which are based on genetic assessment and genetic criteria, qualitative and quantitative indicators of the type of the void space, the intervals of variation coefficients of the open, effective porosity and absolute permeability are defined primarily by core and well logging.
Commercial oil production in the Udmurt Republic has been going on for more than 50 years. Continuous development of oilfi ds has gradually reduced reservoir temperature, increased water cut and made oil composition heavier. Nowadays there are many technologies aimed at prevention and removal of paraffi wax and asphaltene deposits, and each of them certainly has its benefi and drawbacks. Unfortunately, none of the existing inhibitor solutions can fully prevent wax buildup. In fact, such inhibitors only help to increase intervals between treatments. Key research objective implies the search for efficient removal of paraffin wax buildup from downhole pumping equipment, production tubing and gathering pipelines in a way that would ensure quicker treatment and smaller amount of chemicals used.
Enhanced oil recovery is a vital issue for all petroleum companies. As is well known, recovery of oil reserves is non-uniform across the field, with recovery factor rarely exceeding 0.4, which is especially notable in reservoirs of complex geology. Drainage of oil reserves is also significantly affected by discrepancies in directions of regional horizontal stresses. Movement of injected water and propagation of natural and hydraulic fractures go along thedirections of maximum stresses, thus increasing poorly swept areas. Changing fracture propagation patterns enables better stimulation of the pay zone and recovery of bypassed and dead-end oil as well as extraction from lenticular and semi-lenticular beds, increment of recovery factor, expansion of candidate well selection criteria, and maintaining oil production levels.
Based on individual composition of saturated and aromatic hydrocarbons, the paper presents geochemical properties of oil from 20 different fields in the central area of Siberian craton. The study reveals that initial organic matter of observed crude oils was formed in marine environment of high salinity. By their geochemical properties, crude oils are divided into two groups: group one refers to Riphean sediments of Baykitskaya petroleum-bearing region (PBR) and group two refers to Vendian-Cambrian sediments of Katangskaya and Nepsko-Botuobinskaya PBR.