Preview

Oil and Gas Studies

Advanced search
No 5 (2020)
View or download the full issue PDF (Russian)
https://doi.org/10.31660/0445-0108-2020-5

GEOLOGY, PROSPECTING AND EXPLORATION OF OIL AND GAS FIELDS

8-19 1141
Abstract

The article deals with the results of studies of the geological structure features of the US2 oil-bearing stratum in the upper part of Tyumen suite (a case study of the Surgut arch fields). Object US2 is represented by low-permeability reservoirs with complex facies variability and an uneven distribution of reservoir properties over area and section, characterized by a thin-layered structure. In this regard, the oil reserves of the US2 structure are naturally classified as hard-torecover, requiring additional work to further study its structure and features for effective development of oil reserves.
The facies of river channels, riverbank shoals and sands of floodplain spills were identified, based on the analysis of geological and geophysical materials: 3D seismic survey, core studies, well testing data, sampling and dynamics of wells operation in the area of the deposits in the upper part of the US2 horizon. Based on the analysis of the detailed correlation, three types of section of the US2/1 formation were identified, differing in the nature of the reservoir spread.
Based on the 3D seismic survey data, in order to clarify the structure of the US2 formation, a dynamic analysis of the attributes of the seismic record was carried out. Significant coefficients of cross-correlation between the dynamic characteristics and production parameters of the US2/1 formation were not obtained. It is necessary to develop optimal methods for exploration and clarification of the features of the geological structure and forecasting the distribution of reservoir properties, rational methods and approaches to the development of hard-to-recover reserves of Tyumen suite objects with a complex distribution of reservoir properties and variability of productive thicknesses.

20-35 630
Abstract

The article is devoted to the hydrogeochemical conditions of the Mesozoic hydrogeological basin within the Russkoye oil and gas field. The text gives valuable information on the natural conditions, geological structure, geotemperature regime of the bowels of the Earth and the composition of groundwater of the Aptian-Albian-Cenomanian, Neocomian, and Jurassic hydrogeological complexes. The change in the composition of groundwater in the section of the AptianAlbian-Cenomanian complex has been revealed. Vertical inversion zoning that traces the underlying the Neocomian complex is established. We describe the main features of the regional distribution of reservoir pressures. Hydrodynamic schemes of the Aptian-Albian-Cenomanian, Neocomian, and Jurassic hydrogeological complexes are given in the article. These schemes show that the Russkoye gas and oil field is located in the zone of low reservoir pressures. The above vertical inversion zoning and low reservoir pressures are associated with the location of the field within the elisional hydrodynamic water pressure system of the Yamal-Gydan lineaments. The data of the block-fault model of the considered field were used in the course of the study. The block-fault structure predetermined the migration of hydrocarbons and the formation of tectonically screened deposits.

36-52 774
Abstract

The use of the method of seismic data acoustic inversion, in the presence of thick gas cap, can lead to difficulties when building background models of elastic parameters. In this regard, in the conditions of acoustically contrast thin environments within the perimeter of the Russkoye oil and gas condensate field, in addition to the standard version based on the well data, the authors considered a number of modified techniques ("block", "flat", and background models). The use of these background models provided the best results and made it possible to significantly improve the quality of predicting rock properties; based on the drilling results, effective penetration was ensured at 66 %, which was 102 % of the plan. Also, based on the inversion results, it became possible to predict reservoir properties using the Bayesian lithotype classification method.

DRILLING OF WELLS AND FIELDS DEVELOPMENT

53-63 368
Abstract

The article is devoted to the problem of mechanical velocity measurement in deep wells. The standard error limit is set at 2,5 %. However, the existing methods of measurement of drilling parameters have large errors associated with the presence of friction forces in the well, temperature changes with depth, column layout, etc. The error is also introduced by the discrete measurement method, which manifests itself in smoothing of the useful signal and delay in the information about the speed value by half the averaging interval. The aim of the work is to determine the realistically achievable values of the mechanical drilling speed. For this, the reduced error was calculated according to the upper limit of measurement in accordance with GOST. The dependence of the error on the depth of the well and the drilling speed is graphically presented. The error estimation for different type of drilling and different column layout is given. The analysis of the obtained results showed that the set value of the error can be achieved not in the entire range of changes in the speed and depth of the well bottom.

64-73 583
Abstract

The article is devoted to the issue of control and regulation of the high-quality operation of a submersible motor with a long overhaul period. There are some complications of operating the electric submersible pump. One of them is the thermal interaction of the borehole fluid and components and parts of the electric submersible pump that leads to failure and repair. It is necessary to conduct research in the field of physical and hydrodynamic calculations to determine the effect of heat exposure. The article reveals one of the approaches to solving the problem of thermal interaction between a well and the electric submersible pump. We describe calculations of the winding temperature of a submersible electric motor for specific conditions in a particular well, including different modes of fluid flow, different loads of the submersible motor, and different concentrations of oil in water. The development of the described technique will allow creating special software aimed at determining the areas with the highest temperature of the motor winding, taking into account various parameters that affect the heat transfer process.

74-80 543
Abstract

A complex of special equipment is required for the construction of high-tech wells. The basis of modern time efficient, precise and safe drilling is rotary steerable systems (RSS).
For the past five years, rotary steerable systems have been using in Russia as a technical and technological solution to reduce accidents and to improve the quality of well construction with large vertical deviations of the extended drilling radius. These systems allow drilling to be oriented along the entire length of the well.
Rotary steerable systems allows drilling both perfectly vertical wells with a deviation angle of not more than 0,2°, and horizontal wells more than 2 000 metres long.
Implementation of rotary steerable systems allows building wells with extremely extended reach and conducting wells in 1–2 metres thick reservoirs with precision.
In 2016, OktoGeo LLC carried out pilot well program with APS Technology's 172 mm RSS (with power section) at an oil field in the territory of KhantyMansiysk Autonomous Okrug — Ugra.
All the rotary steerable system positioning programs were completed based on the results of that work and results of drilling 2 205 metres long directional well.

81-93 530
Abstract

The article is devoted to the quality of well casing at the Pyakyakhinskoye oil and gas condensate field. The issue of improving the quality of well casing is associated with many problems, for example, a large amount of work on finding the relationship between laboratory studies and actual data from the field; the difficulty of finding logically determined relationships between the parameters and the final quality of well casing. The text gives valuable information on a new approach to assessing the impact of various parameters, based on a mathematical apparatus that excludes subjective expert assessments, which in the future will allow applying this method to deposits with different rock and geological conditions. We propose using the principles of mathematical processing of large data sets applying neural networks trained to predict the characteristics of the quality of well casing (continuity of contact of cement with the rock and with the casing). Taking into account the previously identified factors, we developed solutions to improve the tightness of the well casing and the adhesion of cement to the limiting surfaces.

DESIGNING, CONSTRUCTION AND OPERATION OF PIPELINE TRANSPORT SYSTEM

94-103 513
Abstract

Maintaining of the pipeline system in an operational condition can't be achieved without solving the problem of their protection from internal corrosion as the main factor that leads to numerous accidents. In conditions of limited funding, the creation of scientifically based methods that regulate repair work on difficult areas [1] or those that are not repairable using "classical" methods is a very urgent task. In this way, the use of repair methods without stopping product pumping, in terms of justifying the placement of technological equipment, even more increase the importance of the problem being solved.
Research methods are experimental and theoretical character and based on the analysis and processing of statistical data received during the experimental studies of field objects.
The result of this work was the creation of a methodology that allows determining the order of repair work on pipelines with different degrees of corrosion damage and its speed on different sections of the route [2]. And as a result, reasonable placement of technological equipment along the pipeline route for in-line pipeline repair, without stopping the pumping of the transported product.

CHEMISTRY AND CHEMICAL TECHNOLOGIES

104-111 478
Abstract

The waters of oil fields are characterized by low concentrations of iodine. It is required to create new technologies for the extraction of iodine from groundwater, which will reduce the iodine deficiency in Russia. It is necessary to organize the production of iodine from oil waters, in order not to depend on imports. The construction of new factories producing iodine is extremely timeconsuming and costly. Therefore, the issue of the integrated use of produced water requires an immediate solution not only in Western Siberia, but throughout the country. This requires work on new technologies to maximize the use and application of groundwater in order to get that done. The availability of cheap iodine in unlimited quantities can influence new nanotechnologies, contribute to the creation of points of growth for various industries (lasers, computers, etc.).

MATERIALS AND STRUCTURES IN THE OIL AND GAS INDUSTRY

112-119 376
Abstract

The article is devoted to the results of studies, which have been conducted on parts with electrolytic chromium in order to determine the effect of the coating on fatigue strength of their. The work was performed in observance of standards, which are fixed in GOST RV 2840-001-2008. Samples for the tests were made from standard gas turbine engine compressor blades. We used a VEDS- 1500 electrodynamic vibration stand with an UMK-12K power amplifier to excite vibrations. It has been shown that the minimum endurance limit of 46 kgf/mm2 based on 2 ∙ 107 cycles, established on uncoated parts, didn't decrease during fatigue tests of compressor blades with an electroplated chrome layer. It should be stressed that the influence of the geometry of the chrome-plated part on the reduction of the endurance limit has been established.



ISSN 0445-0108 (Print)