UDC: 622.276
BBK 33.361
A43

Editorial council:
V.A. Baykov
A.P. Bespalov
V.N. Zvereva
A.V. Kolonsky
S.V. Kostyuchenko
A.M. Kuznetsov
A.M. Petrakov
D.A. Skuba
E.N. Chernyshov
Editing:
V.I. Fedorova

Nowadays hydrodynamic modelling is the base for projecting and supporting the fields. Adequacy of the hydrodynamic model is connected with quantity and quality of initial data, and with petrophysical properties. In this case, in practice, there is a situation where there are problems with the quantity and / or quality of the source data. This problem can be solved using the Digital Core technology.

In this article is described the developed stochastic pore-network model, presented the results of testing the created computer program, and examines the results of its application to substantiate the porosity-the absolute permeability dependence of the BV formation of Samotlorskoye field.

Presented in the work the stochastic pore-net model of virtual rock samples was constructed in two stages. The first stage is the stochastic reconstruction of the void space. Capillary pressure curves were used as an initial information. The adjustment of the stochastic model to core data was carried out by correlation and topological parameters, such as the maximum coupling radius (directly affects the coordination number), weight functions, etc. The second stage is the absolute permeability calculation, starting from a numerical simulation of a single-phase incompressible fluid flow in pore channels. For this, the equations of hydraulics are used: the equations of the mass balance in the pores and the equations for the fluid flow in the channels (Poiseuille equations).

With the purpose of studying the object, several stochastic porous-network models were created with detailed tuning to cores data taking into account the lithological description of the samples. As a result of averaging a large number of calculations, the correlation dependence between the absolute permeability and the porosity was refined. Based on the calculation results, a new porosity-absolute permeability relationship characterizes the rock as having better petrophysical properties than the previously valid dependence. The improvement of the filtration-capability properties also agrees with the results of well research.

The application of the new dependence in the hydrodynamic model shows a marked improvement in the correspondences between calculated and actual development data, which indicates the legitimacy of the resulting petrophysical dependence.

In this work the results of applying the developed software for numerical analysis of oil well work on reservoir BV₈^1-3 of Samotlorskoye field. A computer program is created on the basis of physical-mathematical model describing the filtration of oil and water in the reservoir, including taking into account the nonequilibrium relative phase permeability (RPP) model by G.I. Barenblatt.

The work shows the results of testing a computer program, including the use of computational grids of different configurations and detail. It was found that acceptable quality and time calculation work well can be uniform design grid. Also we consider the results of a study of the influence of the ways of solving systems of linear equations.

The work shows the research results of well water cut dynamics depending on its work mode and characteristics of the reservoir. In all cases, the nonequilibrium RPP leads to having expressed pulsations of water cut.

The technique of assessment of coefficient of oil-and-gas saturation of complex structure, including low-impedance collectors is developed, according to standard logging of PS in a complex with the GIS electromethods where the static potential of EPS pays off according to the IntREst© program and the functional dependence "kern-GIS" the static potential of EPS from volume humidity of W is under construction. The example of interpretation of the low-impedance petrosaturated collectors of the Jurassic deposits Low-key, Polesia (Severo-Eguryakhsky-2 of LU) fields of LLC LUKOIL-West Siberia is given.

Studies on the topic of mathematical modeling of reservoir filtration and capacitance properties were carried out in the department for the creation and monitoring of geological models of the PermNIPIneft Branch of LUKOIL-Engineering LLC in Perm. The basis for the work was the need to test the method of the hydraulic flow unit at the Perm region deposit. The main task was to identify the regularities and characteristics of each class of the reservoir, separated by the indicator of the hydraulic flow unit. Graphical and geological-statistical processing of information was carried out using MS Excel, Statistica and IRAP RMS. For the study, a geological model of the Bb bed of the Moskudinskoye field was chosen.

For the facial complex of the delta channel, isolated during the core analysis and geophysical studies of the wells, some dependencies of the decrease in filtration-capacitive properties with depth increase were determined using the hydraulic flow unit indicator. Groups of values are defined that form linear equations with similar values of the angular coefficient. The features of each group are considered taking into account their getting into this or that class of the collector. A number of factors influencing the differences in changes in the properties of the reservoir were formed.

The most thoroughly investigated was the assumption of a clay material. Analyzing the graphs of the distribution of the coefficient of clayiness with depth for each of the isolated groups, the hypothesis was confirmed: with increasing depth, the coefficient of clayiness increases, thereby reducing the filtration-capacitive properties.

From the presented geological and statistical section of the previously identified groups, it became clear that the top of the section is represented to a greater degree by the rocks belonging to the group possessing the best filtration and capacitance properties. To the bottom of the section, the predominance of rocks of the group with lower properties is increasing.

The carried out researches allow to draw the following conclusion. The allocated groups have a different degree of accumulation of clay material. Greater clay is traced below the level of water-oil contact. The change in the properties of the clay material during the development of the deposits will worsen the reservoir filtration and capacitance properties. This decompaction, in turn, is the source of the energy of the reservoir for the selected groups. Differentiation of these groups makes it possible to specify in which sections of collectors these processes will pass, and in which they will not be significant. This will allow us to correctly understand the development of deposits, the design of drilling new wells and the adaptation of geological and hydrodynamic models

The current waterflooding system at the Achimov formation of the Potochnoye field is estimated, and method for increasing efficiency is proposed. The results of implementing the proposed solution are shown. The authors showed the dynamics of the indices at different distances between the injection and production wells, and substantiated the insufficient current efficiency and proposed a solution due to the transformation of the waterflooding system. The authors carried out comparative calculations of the operation of an isolated section of well area № 118P of the Achimov formation with the use of a sectoral hydrodynamic model to substantiate the efficiency of transformation of the development system. After the calculations made the program of industrial testing of the method was proposed.

The authors proposed the transformation of the implemented waterflooding system on the nearby section by transferring a part of the low-productive extraction fund to water injection, prepared and presented the address program of the development to maintain reservoir pressure in experimental industrial works. The proposed solutions are fulfilled. The authors have estimated the volumes of additionally produced oil and the economic efficiency of the program. For 2016, the economic effect amounted to 89.7 million rubles.

Requirements for reservoir model quality have significantly increased by the last few years.  Number of well operations and duration of oil production are constantly increasing. Reservoir simulation is used not only for the field development projects, but also for most well operations at the present time. Import software is widely used for these calculations. Restrictive sanctions and high cost of import software necessitate Russian oil companies to develop their own simulators.

This article contains the description of the developed modules for corporative reservoir simulator «TecScheme». These modules are used for quality control of geological and hydrodynamic models and operational planning.

According to the currently accepted methodology applied to shale oil prospecting (in Bazhenov rocks), total organic carbon (TOC) in Bazhenov rocks is one of the key factors in prospective area assessment. The prospected TOC areal distribution is primarily obtained as a result of core sample laboratory tests, and it does not always correspond to the real geochemical environment owing to insufficient amount of investigations. This fact makes detailed TOC forecasting on the scale of the study area, and subsequently, defining potentially prospective areas difficult. To solve the above mentioned problem the author proposes TOC forecasting technique using well logging data which is based on correlations of geochemical parameters with parameters obtained by spectral gamma-ray logging (SGR).

The research target is wells located in different oil-gas bearing areas within Tomsk Oblast which were subject to laboratory tests on Bazhenov rocks, using Rock-Eval pyrolysis, in particular, and advanced well logging. Both pyrolysis investigations of core samples (TOC) and spectral gamma-ray logging (uranium, potassium and thorium mass content) provided input data for technique validation.

Based on the observed regularity indicating that Bazhenov bituminuous argillite radioactivity is due to uranium sorption enrichment, the correlation between total organic carbon content and uranium content determined by spectral gamma-ray logging throughout the Bazhenov section was considered.

The research is aimed at the study of the geology and geochemistry of the Domanic formation in the Republic of Bashkortostan as a promising exploration target and a reservoir for shale oil and gas. The Domanic sediments are confined to the Domanic Fm. of the Upper Devonian and are widespread almost throughout the Republic. The study included the lithology and facies analysis, evaluation of HC occurrences in this section, geochemical measurements on core such as TOC, vitrinite reflectance (Ro) and pyrolysis. The Domanic Fm. is characterized by TOC values from 3.0 to 29.1% wt. The pyrolysis data indicates the maturity of the source rock (organic matter) at stages MK1 to MK2 of the mesocatagenesis corresponding to the main oil window, as also supported by Ro values ranging from 0.46 to 0.71. For the first time pressure and present-day temperature were mapped adjusted to the top of the Domanic formation. to recreate the burial history and maturation. The in-situ temperatures and pressures increase southwards in the direction of the Mrakov Depression. The research area was then divided into zones based on their HC potential. It was found that the Domanic formation. is most prospective within the Verkhne-Kamskaya Depression, margins of the Bashkir Arch, the north-eastern margin of the Tartar Arch and the adjacent areas of the Blagoveschensk Depression and Birsk Saddle. The novelty and applicability of the research lies in the use of the obtained geochemical findings from the Domanic formation. for evaluation of its maturity, correlation of the pressure and temperature data against the optimum criteria for finding the so-called sweet spots or most prolific production zones. The research also resulted in recommendations for planning further exploration efforts in the south-east of the Mrakov Depression where this play is assumed to have highest petroleum potential.

The information and analytical WellInfo system (further - IAS WellInfo) represents the hardware and software system intended for loading, storage, granting to users and unloading of all range of geologic-geophysical, trade and other information on oil-and-gas fields. 
The main prerequisites of creation of IAS WellInfo is reduction of costs of search and improvement of quality of initial information during creation of scientific and technical works. At the moment IAS WellInfo possesses a role of the central storage of all range of geological, geophysical and trade information.
The standard configuration of IAS WellInfo includes the database, the application server, a workplace of the client, the GIS-server and the program of loading of logging curves.
The WellInfo database consists of more than 1300 tables in which more than 30 000 attributes, and the electronic catalog of documents are defined. As a control system of data Oracle Database 11g Enterprise Edition functioning in the Oracle Enterprise Linux operating system is used.
The application server is developed as a web application on the basis of a stack of Java Enterprise Environment technologies. The client application is run on Adobe Flash Player technology in the ActionScript v.3 language and functions on the user computers under control of operating systems of the Windows family. 
The architecture of the application server is under construction on modular type. A set of the basic technologies which are responsible for functioning of system in general is concentrated in a system kernel. The functionality of IAS WellInfo is broken into separate modules. In total in system there are eleven applied and seven office modules. 
The main directions of development of IAS WellInfo for the following version are formulated.