Finding the Best of the Best: Hydraulic Fracturing Design Optimization Study in Oman

Development of the tight gas Khazzan Field in Sultanate of Oman has progressed through an extensive learning curve over many years. Thereby, the hydraulic fracturing design was fine-tuned and optimized to properly fit the requirements of the challenging Barik reservoir in this area. In 2018, BP Oman started developing the Barik reservoir in the Ghazeer Field, which naturally extends the reservoir boundary south of Khazzan Field. However, the Barik reservoir in the Ghazeer area is thicker and more permeable than in the Khazzan Field; therefore, the hydraulic fracturing design required adjustment to be optimized to directly reflect the reservoir needs of the Ghazeer Field. A comprehensive hydraulic fracturing design software was used for this optimization study and sensitivity analysis. This software is a plug-in to a benchmark exploration and production software platform and provides a complete fracturing optimization loop from hydraulic fracturing design sensitivity modelled with a calibrated mechanical earth model to detailed production prediction using the incorporated reservoir simulator. One of the stimulated wells from Ghazeer Field was used as the reference for this study. The reservoir sector model was created and adjusted to match actual data from this well. The data include fracturing treatment execution response, surveillance data such as radioactive tracers, bottomhole pressure gauge, and pressure transient analysis. Reservoir properties were also adjusted to match long-term production data obtained for this reference well. After the reservoir model was fully validated against actual data, multiple completion and fracturing scenarios were simulated to estimate potential production gain and thus find an optimal hydraulic fracturing design for Ghazeer Field. Many valuable outcomes can be concluded from this study. The optimal treatment design was identified. The value of fracture half-length versus conductivity was clarified for this area. The comparison between single-stage fracturing versus multistage treatment across the thick laminated Barik reservoir in a conventional vertical well was derived. The drainage of different layers with variable reservoir properties was compared for a range of different scenarios.

Field-Scale Modeling of Smart Completion Tools for Optimum Recovery

Flow control devices (FCDs) like inflow control devices (ICDs) and interval control valves (ICVs) (i.e., equalizer) have increased applications in both conventional and unconventional resources. They have been used to mitigate water or gas coning problems for mature fields in conventional reservoirs, to alleviate premature water breakthrough in naturally fractured reservoirs, and to optimize the steam distribution in heavy oil reservoirs. There have been increased trend in using FCDs in the real field. Previously, complex well models have been implemented in a large-scale parallel reservoir simulator by Tareq et al. (2017). The implementation can simulate an intelligent field contains tens to hundreds of multilateral complex wells commonly referred in the literature as maximum reservoir contact (MRC) wells with mechanical components such as ICVs and ICDs. In this paper, a new framework to model controlling the FCDs in complex well applications will be presented. The implementation is integrated into a complex well model. It can be easily used to model the dynamical control of devices. Simulation studies using both sector model and field model have been conducted. A systematic full-field operation is used for device control applications of smart wells. Successful application of field level controls in smart wells has the benefit of the improved overall GOSP performance.

Advanced Multi-Disciplinary Simulation Workflow for Well Placement, Hydraulic Fracturing and Production Optimization Applied to the Diyab Unconventional Play in Onshore UAE

The Diyab play is an emerging unconventional play in the Middle East. Up to date, reservoir characterization assessments have proved adequate productivity of the play in the United Arab Emirates (UAE). In this paper, an advanced simulation and modeling workflow is presented, which was applied on selected wells located on an appraisal area, by integrating geological, geomechanical, and hydraulic fracturing data. Results will be used to optimize future well landing points, well spacing and completion designs, allowing to enhance the Stimulated Rock Volume (SRV) and its consequent production. A 3D static model was built, by propagating across the appraisal area, all subsurface static properties from core-calibrated petrophysical and geomechanical logs which originate from vertical pilot wells. In addition, a Discrete Fracture Network (DFN) derived from numerous image logs was imported in the model. Afterwards, completion data from one multi-stage hydraulically fracked horizontal well was integrated into the sector model. Simulations of hydraulic fracturing were performed and the sector model was calibrated to the real hydraulic fracturing data. Different scenarios for the fracture height were tested considering uncertainties related to the fracture barriers. This has allowed for a better understanding of the fracture propagation and SRV creation in the reservoir at the main target. In the last step, production resulting from the SRV was simulated and calibrated to the field data. In the end, the calibrated parameters were applied to the newly drilled nearby horizontal wells in the same area, while they were hydraulically fractured with different completion designs and the simulated SRVs of the new wells were then compared with the one calculated on the previous well. Applying a fully-integrated geology, geomechanics, completion and production workflow has helped us to understand the impact of geology, natural fractures, rock mechanical properties and stress regimes in the SRV geometry for the unconventional Diyab play. This work also highlights the importance of data acquisition, reservoir characterization and of SRV simulation calibration processes. This fully integrated workflow will allow for an optimized completion strategy, well landing and spacing for the future horizontal wells. A fully multi-disciplinary simulation workflow was applied to the Diyab unconventional play in onshore UAE. This workflow illustrated the most important parameters impacting the SRV creation and production in the Diyab formation for he studied area. Multiple simulation scenarios and calibration runs showed how sensitive the SRV can be to different parameters and how well placement and fracture jobs can be possibly improved to enhance the SRV creation and ultimately the production performance.

A Multi-Process Reservoir Modelling Workflow as the Key for Unlocking Reservoir Prediction in Carbonates. Application to a Sector Model from the Albion R&D Project

In carbonate reservoirs, because of the diversity of geological processes involved in the reservoir construction, the extrapolation of properties directly from well data to reservoir model gridblocks may lead to poorly predictive reservoir properties and then production forecasts. This paper proposes a modelling workflow in which new tools from disruptive technologies are associated in order to produce reservoir models consistently with reservoir geological construction. The workflow combines the simulation of the depositional facies and their transformation after diagenesis overprint. Original depositional facies are carried out from SED-RES™, a stratigraphic forward modelling software that generates and transports carbonate sediments according to ecological conditions and wind-induced currents. Then GODIAG™, a lattice gas, reproduces the evolution of the properties of the sediment after it has been deposited. The diagenesis history can be multi-stage and can involve different kinds of physical and chemical reactions. This new workflow has been evaluated in the framework of the ALBION R&D Project dedicated to the study of the Barremian-Aptian rudist-rich carbonate platform from south France that is known as an analogue of the Kharaib and Shuaiba reservoirs (UAE). Thanks to its multi-scale and multi-site aspect, ALBION offers the opportunity to test new modelling tools. The efficiency of the new workflow has been successfully applied on a sector model from an ALBION site on which a rich geological and petrophysical dataset is available from outcrops and numerous wells,

Understanding of Vertical and Horizontal Pressure Barriers in the Naturally Fractured Carbonate Field

The Karachaganak field is a massive reef carbonate structure. The main reservoir is of the late Devonian-Carboniferous age, where sequence stratigraphic cycles of progradation and aggradation defining the growth stages of the carbonate build-up have been revealed. Vertical and horizontal semiconductive barriers was identified in the reservoir during the field development. It was assumed that these barriers are located at the boundaries of the changing depositional cycles, which took place during the reef structure growth. According to the simulation results on a sector model of the reservoir it was determined that the pressure barriers can be developed due to different fracture intensities observed in the reservoir and not because of rock property as such. The reason for the different fracture densities may be associated with compaction during primary diagenesis and may have a sync-depositional nature, which can be seen on carbonate structure outcrops.

Financial Sector of Russia: 30 Years of High Volatility Inside Global Finance

The article provides a comparative analysis of the financial sector of Russia and other countries in the structure of the global economy; international comparisons are made over 30 years in terms of financial depth, including monetization, “saturation” with loans and securities, inflation, and interest rate. The inadequacy of the size of the financial sector to the size of the Russian economy is shown, the extremely high volatility of financial variables is analyzed (using the example of the exchange rate and changes in the institutional network (banks and non-bank financial institutions)). The model of the financial sector is revealed (excessive role of the state, overconcentration in the markets and among financial institutions, oligopolization, “monetary desertification” of regions, excessive administrative costs, focus on capital export). Shown is the “pro-crisis” nature of the financial sector in Russia (1– 2 crises in 10–15 years). The complete correspondence of the parameters of the financial sector of Russia to other developing economies is demonstrated (the fourth – seventh dozen countries in terms of financial depth). It is shown that the parameters of financial development, as a rule, are worse than the groups of countries with lower middle income (according to the international classification). The analysis of the Russian economic model made it possible to show the cause-and-effect relationships between it and the financial sector model, their interdependence. Four scenarios of the economic future (“besieged fortress”, “frozen economy”, “Spanish”, “growth economy”) are given, with estimates of their probability, and on this basis the corresponding scenarios for the future development of the Russian financial sector. The scenario of the “growth economy” based on the change in the model of the economy in Russia, the policy of “financial afterburner” and the formation of a new model of the financial sector in Russia is more fully disclosed.

Value principles of the equilibrium economic development in the new global challenges

The paper reveals that the formation of the information society at the turn of the century with a focus on a network economy marked the beginning of the economic relations and laws system global modification. This modification is due primarily to the latest technological changes and innovations in information and communication. However, in its profound nature, it has a value character and is associated with the need for a thorough understanding of the new socio-economic picture of the world. The traditional interpretation of this situation does not meet public expectations about progressive, creative development possibilities. Public dissatisfaction with globalisation is growing. Phenomena of socio-economic instability (turbulence) and uncertainty undermine the civilisational foundations of the social economy, create several global challenges and threats. It is shown that an adequate guideline for successful management is to ensure balanced social development through the development of a holistic institutional architecture, which operates under the laws of effective economic equilibrium. Economic theory is designed to substantiate the laws of operation and the principles of building the institutional architecture of management. At the same time, modern economics remains traditional, while the correct answer to the global social demand must be given by relativistic economics, which can form the socio-economic foundations of the phenomenon of relativity. It is determined that the concept of the institute as a transformed form of economic value (economic good, the only one in the triple definition of marginal utility, value, and price) is an adequate basis for building relativistic economics, methodological source of creative knowledge and formation of the latest holistic picture of the world. It is noted that the tools of value economic analysis (in particular, the model of general economic equilibrium) were formed in the depths of classical political economy, but today it needs to be updated. It is established that the methodological restoration of economics as a valuable source of a positive relativistic understanding of the latest world picture is an essential agenda for further creative research to determine the principles of building an economy of trust forerunner of the institutional architecture. The basis of such an economy is a public sector model focusing on the market of public goods, which harmonises the system of public interests, processes of self-organisation and organisation in the economy, thus contributing to the formation of effective mechanisms for stabilising social development.