bluuebunny/crossref_metadata_2025 huggingface dataset:
Warming tolerance across insect ontogeny: influence of joint shifts in microclimates and thermal limits
Authors: Pincebourde Sylvain , Casas Jérôme
Published: September 2014

The impact of warming on the persistence and distribution of ectotherms is often forecasted from their warming tolerance, inferred as the difference between their upper thermal limit and macroclimate temperature. Ectotherms, however, are thermally adapted to their microclimates, which can deviate substantially from macroscale conditions. Ignoring microclimates can therefore bias estimates of warming tolerance. We compared warming tolerance of an insect across its ontogeny when calculated from macro‐ and microclimate temperatures. We used a heat balance model to predict experienced microclimate temperatures from macroclimate, and we measured thermal limits for several life stages. The model shows a concomitant increase in microclimate temperatures and thermal limits across insect ontogeny, despite the fact that they all share the same macroclimate. Consequently, warming tolerance, as estimated from microclimate temperature, remained constant across ontogeny. When calculated from macroclimate temperature, however, warming tolerance was overestimated by 7–10°C, depending on the life stage. Therefore, errors are expected when predicting persistence and distribution shifts of ectotherms in changing climates using macroclimate rather than microclimate.
Successful Application of Through Casing Logging Technology To Increase Oil Production in a Brown Field Well
Authors: Salimov Farid , Plugin Stanislav , Kramer Hermann
Published: September 2014

Oil Producers are challenged every year to keep their companies profitable. The challenge can be met by implementing technologically advanced solutions. One of the solutions widely implemented in West Siberia is drilling side-track horizontal wells. In spite of high efficiency, this approach requires high quality formation information for successful well placement and completion. One of the technologies that provide high quality formation evaluation data through the casing is four detectors neutron-neutron and neutron-gamma QUAD technology.
Refracturing is the Best Way to Develop Hard-to-Recover Reserves in Romashkino Oilfield Conditions
Authors: Khusainov R. , Ganiev B. , Karimova A. , Karpova O.
Published: September 2014

Today hydraulic fracturing is proved to be the most reliable and effective method of well stimulation. Specialists of NGDU are performing hydraulic fracturing efficiently, taking into account the quality of wells selection, introducing mode of treatment in order to provide an optimal geometry of fracture and get the highest production index from every well.

In spite of the fact that repeated hydraulic fracturing is widely spread and used, all works are narrow directed. Considering either treatment results or, vice versa, describe process design. In this work we tried to identify treatment mode dependence, which allows generating required geometry of the fracture in accordance with different factors and then, estimate obtained results of well production increase and incremental ultimate recovery. Refractured wells were chosen for qualitative assessment of hydraulic fracturing to estimate correctness of project modes and treatment result more exactly. It will also allow improving efficiency not only from refracturing, but also from first treatments.
Integrated Workflow To Tackle Heterogeneous Karst Dominated Reservoirs: Kharyaga Example
Authors: Neillo V. , Pauget L. , Neumann C.
Published: September 2014

Kharyaga Upper Devonian oil reservoir, developed through water injection, is part of a highly heterogeneous carbonate platform. Three sedimentary domains can be identified from South to North: a microbial reef-flat, back-barrier grainy shoals and a non-reservoir lagoon. Static and dynamic data gathered since production start-up revealed that the barrier is extensively fractured and karstified and shows a dual permeability behavior. Understanding the distribution of the dual medium is key to successful development of such a complex reservoir.

To capture the relative weight on the flow network of each type of heterogeneity, a new workflow to characterize the dual medium has been developed, including the following steps: karst facies identification from cores and borehole images, comparison of the karst facies over a detailed flow analysis including detailed PLT interpretation; analysis of the facies spatial distribution using various diagenetic scenarios. As a result a new integrated vision of the reservoir and flow system has been consolidated and 3 main emersions followed by a hydrothermal phase have been identified. Each individual emersion generated a complex karst system composed of several components linked to the paleo-topography.

Representing properly such a heterogeneous system was coped with by iterating in order to match the dynamic data. A two-stage modeling workflow was used: (1) fast iteration process using a dedicated stochastic tool which generates karst conduits, constrained by infiltration zone, paleo-water-table and paleo-topography; (2) once the right inputs are captured, the forward modeling workflow simulated the process of dissolution and generated at very fine scale a more complex and more consistent system.

Finally, this work allowed to model different representations of this complex reservoir capturing the range of remaining subsurface uncertainties and consistent with the integrated interpretation of static and dynamic data. It allows to highlight and evaluate quantitatively the stakes of current and potential new development.
Specification of a Geological Structure of Productive Formations According to Seismic Data in the Process of Drilling
Authors: Gurievskih L. A. , Shelepov I. V.
Published: September 2014

In this article questions of specification of geological models in the process of exploitation drilling are considered on the example of geological structure of U1 fomation. Rather often there is a need of specification of a geological structure of oil and gas deposits, and sometimes even a full revision of existing before conception of geological features of deposits.

Mapping of property distribution of formation using dynamic seismic attributes is a widespreaded way of analysis, but it is not always possible to receive reliable dependences between attribute and properties of formation, especially for the deposits having a complex geological structure. Using seismic prospecting data as dynamic and seismo-facial analysis U1 formation was devided into facies according special generation and accumulation conditions and having different reservoir properties. This approach allowed to get reliable correlation links for calculations seismic attributes into effective thickness maps that were used for determination of location of projected wells.
Techniques for Successful Heavy Oil Sampling with Wireline Formation Testers
Authors: Blinov V. , Weinheber P. , Ivashin M. , Novikov S. , Charupa M. , Filimonov A. , Abramov A. , Nizov S. , Kolobanov A.
Published: September 2014

Unconventional hydrocarbon resources are becoming more and more important to the overall world energy picture and Russia is no exception. Heavy oil has long been an acknowledged asset but renewed efforts to replace the aging conventional resource base are focusing increased attention on this often neglected resource. Many of Russia's heavy oil fields were discovered 20-30 years ago and the formation evaluation data from these old exploration wells is often scanty. Quality fluid samples, especially, were almost impossible to obtain. Aside from the very high viscosity that almost precludes fluid movement, the reservoirs were often either unconsolidated sands with low failure strengths or, in rare cases, carbonates with extensive vug and fracture networks. However, with a renewed focus on these reservoirs, quality formation samples are a necessity.

In this paper we show successful approaches using wireline formation testers to acquire heavy oil sample in two Lukoil fields in the Timan Pechora region: Varandeyskoe and Zapadno-Lekeiyaginskoe. These fields have many differences but two important similarities: very heavy oil and a vital need to understand the fluid properties.
Exploring Petrophysical Uncertainties Thanks to Stochastic Well Log Data Interpretation: Termokarstovoye Field Case
Authors: Samotorova Galina , Bronnimann Bruno
Published: September 2014

Nowadays petrophysical uncertainty is taken into account by major western companies for the field evaluation alongside with existing geological uncertainties. Several published papers review and generalize the main theoretical aspects. However, for Russian companies this idea of stochastic well log interpretation is rather innovative. Thus, the main objective of this paper is to represent the Monte-Carlo simulation method, frequently used in Total for the petrophysical interpretation, on the example of Termokarstovoye field. The stochastic interpretation was performed on two cored wells (providing the uncertainty reduction by the presence of core measurements), logged with wireline PEX tool.

Basically the stochastic interpretation follows the deterministic one and tells how much results vary around the deterministic result. Furthermore, the proposed methodology allows the interpreter to determine the most relevant uncertain parameters on which additional measurements or justifications are required to reduce the petrophysical uncertainty.

Following the described methodology it was identified that the main uncertainty on Termokarstovoye field is saturation. Its influence on the final HCPV (cumulative hydrocarbon pore volume) distribution can be decreased by providing the additional analysis on formation water salinity and by resistivity log inversion, which are the two main impacting parameters.

Thus, experience while running the Termokarstovoye practical case highlighted that, firstly, the final petrophysical uncertainty can be explained and justified. Secondly, further recommendations can be made on new acquisitions to later decrease the uncertainty.
Experimental Studies of Surfactant Adsoption Under Conditions of ASP Flooding at West Salym Field
Authors: Volokitin Y. E. , Koltsov I. N. , Evseeva M. Ya. , Nurieva O. A. , Akhatov I. S. , Kovaleva L. A. , Zinnatullin R. R. , Mavletov M. V. , Kudasheva F. H.
Published: September 2014

To minimize risks related to ASP flooding at West Salym field, experiments have to be carried out to study surfactant adsorption in the formation. Initially one should develop a necessary and sufficient list of experiments, as well as their conditions and interpretation of results. Therefore, two objectives were set: 1) determine the adsorption of anionic surfactant blend in static conditions adding NaCl, Na2CO3, and polymer within the working range of concentrations; 2) determine the adsorption rate of an ASP formulation in coreflood experiments for water- and oil-saturated cores under formation temperatrue.

The main reliability criterion for the results was the reproducibility of the surfactants adsorption experiments and achieving adsorption values within confidence interval. That is why, development of the methods that allow both to achive reproducibility of the results, and to identify sensitivity factors, is a critical aspect of the experiments.

The work presents an interpretation of the experiments for subsequent modeling of processes using mathematic simulators with the view to evaluate surfactant losses in formation during ASP flooding. The achieved results allow further optimization of the ASP cocktail and return a realistic value for surfactant losses in the course of its filtration, as well as ascertain the economic risks inherent to the project.
Treatment of Bottom Hole Zones of Production Wells With Oil-in-Water Emulsions To Restrict Breakthrough Gas Production in Yuri Korchagin Field
Authors: Deliya S. , Golenkin M. , Byakov A.
Published: September 2014

This article is based on field data obtained after seven sessions of bottom-hole zone treatment (BHZT) that were performed in horizontal wells in 2013 and featured fresh water and degassed oil injection for the purpose to restrict the amount of produced breakthrough gas.

This article includes the results of monitoring the performance of the wells before and after the BHZT. It contains information about a new approach to assessment of the well intervention techniques (WIT) with consideration of the effect of decreasing the amount of produced breakthrough gas. The article also contains brief information about other methods of eliminating gas breakthroughs applied by OOO "LUKOIL-Nizhnevolzhskneft".
Unification of Approaches in the Study of the Characteristics of Gas-Condensate Systems
Authors: Fateev D. G. , Nesterenko A. N.
Published: September 2014

Resume

Field and laboratory tests are the source data of formation fluids properties. Any study is uncertain due to imperfectness of the experimental methods and equipment and also due to inaccuracy and errors of measurements. A set of activities aimed at efficient use of the source data of the gas condensate characteristics for mathematical modeling of gas condensate systems has been developed on the basis of analysis and generalization of the results of many surveys of the gas condensate characteristics and the experimental methods and equipment.
Multi-Sensor Technologies for Horizontal Well Production Logging. Current Status and Application Experience in the Fields of Russia
Authors: Valiullin R. A. , Yarullin R. K. , Sharafutdinov R. F. , Ramazanov A. Sh. , Sadretdinov A. A. , Muhkamadiev R. S. , Bazhenov V. V. , Imaev A. I. , Semekin D. A. , Rakitin M. V.
Published: September 2014

Overview of modern well logging methods for research of operating horizontal wells was completed. The possibilities of practical problems solving with the use of application of distributed measurement systems in a horizontal wellbore. Need for mandatory combination of the results of production well logging with mathematical modeling of thermohydrodynamic processes when preparing the final summary was noted. The material contains an examples of production well logging data.

Due to the wide spread of horizontal drilling there are in the global well logging practice areas of work focused on the study operating horizontal wells using multi-sensor technology formed and rapidly developing. Direction of technology development are defined ways of getting information in operating horizontal wells and here are the following ways: Use the remote (or autonomous) downhole tools with distributed across the stream sensors of composition, velocity and temperature moved along the axis of the horizontal section of the well, "scanning" flows under different regimes;Use of several autonomous devices wich are delivered to the fixed depth in the horizontal section of the well with a change in mode of well operation;Use of fiber optic measurement systems, distributed along the length of the horizontal wellbore with the possibility of "instantaneous" temperature record for the entire length of the cable as in monitoring mode, and the mode transients. As additional parameter the bottomhole pressure, and in the future, the acoustic noise distribution is recorded.

The choice of production logging technology depends on the task, geological conditions of the deposit and technical equipment of contractors. Thus, none of the above methods for studying the horizontal wellbore does not exclude the possibility of other approaches, and the areas of effecient use of non-overlapping.

Thus, each of the directions of development of research operating horizontal wells technology has its niche, not limiting the development of existing and newly developed technology solutions. In this case, all methods of horizontal well research combine the need to scan the flow parameters using a plurality of separate (distributed) sensors spaced or transported to a horizontal well.
Development of Microbial Enhanced Oil Recovery Technology for Carbonate Formations: Stage 1
Authors: Khisametdinov Marat , Sokolova Diyana , Fedorov Alexey , Khisamov Rais S. , Ibragimov Nail G. , Nazina Tamara , Babich Tamara
Published: September 2014

Initial stage of development of microbial enhanced oil recovery technology for carbonate petroleum reservoirs is presented. OAO TATNEFT has been successfully employing microbial technology in terrigenous formations for a long time. Results of carbonate reservoir characterization and microbial community analysis show prospectivity of microbial technology development for carbonate reservoirs as well.

It has been found that microorganisms isolated from formation water can produce metabolites with high oil displacing potential when growing on carbohydrates. The main features of microbial method under development are formulated.
Improvement to Wellbore Stability while Drilling Challenging Profile Wells in the Vankor Field
Authors: Kharitonov A. , Burdukovsky R. , Semenikhin I. , Pogorelova S. , Sidubaev S. , Shafigullin R.
Published: September 2014

Various inhibitive additives are used during drilling in the Vankor deposit to stabilize the clay slate, such as Polyacrylamides, Acrylic polymers, inorganic Silicates, Asphaltens and Glycol mixtures. These reagents are used in aqueous slurries to help drill surface casing and process and extract columns.

Complex drilling conditions related to well trajectory, increased penetration speed, and increased rate of locating an instrument at the bottom hole continue to warrant the search for improved tools to better penetrate wells, increase wall stability, and optimize the drilling slurry process. For such reasons, it was decided to perform an industrial test on a new compositional inhibitor with a secondary function as a lube additive and microsealant.

The service company proposed (and the operator supported) compositional inhibitor testing consisting of a dissolved sulfur asphalten mixture in glycol in certain proportions specially developed to increase the efficiency of inhibitive properties and the multifunctionality of an additive.

The testing was applied in a complex well (168° along the azimuth, horizontal projection length of 1,771 m, and a penetration angle of unstable argillites at 63.5°) to help demonstrate the technical efficiency of the new reagent (full dispersion in the aqueous drilling fluid, reduced processing time, and improved productivity of the treatment system) and the practicality of launching it (reduction/replacement of single-component inhibitors) in industrial volumes within Vankor field wells.
Artificial Neural Networks in Drilling Troubles Prediction
Authors: Lind Yuliya B. , Kabirova Aigul R.
Published: September 2014

Drilling of oil and gas wells is a basic process in production of hydrocarbons. Up to now drilling projects are often being designed on the base of segmental data and primary analysis of drilling experience, which is ineffective under modern drilling conditions. A possible solution of this problem consists in computer analysis of data on earlier drilled wells with the use of modern information technologies. Authors propose methods for prediction of probable troubles occurring while drilling new wells on the base of information on well stock of the oilfield using efficient data mining tools – artificial neural networks. Structural and parametric identification of a neural network solving the formalized problem of functions approximation has been conducted. Results of computational experiments on real data show effectiveness of software developed.
Overview of Solids Transport Studies and Applications in Oil and Gas Industry – Experimental Work
Authors: Li J. , Luft B.
Published: September 2014

The transport of solids is encountered in well bore drilling, completion, intervention and production operations. It is affected by many variables and the complexity of the process presents challenges to the field engineer who is trying to determine how these parameters affect solids-transport even if only one of these variables is changed. Historically, solids-transport studies focused mainly on determining the minimum critical velocity to prevent the formation of a stationary debris bed in the wellbore annulus for conventional rotary drilling with mud fluids. Over the past 10 years, the research and development focus has been on obtaining information related to the prediction of the equilibrium solids concentration profile along the whole well path during tripping in, the wiper trip speed during tripping out, and the prediction of the hole-cleaning time. Various computer models have been developed that, to some extent, guide the field engineer in the design and optimization of the solids transport process. However, due to its complexity and incomplete experimental data, a comprehensive, proven and reliable model still does not exist at present.

In this paper, based on 20 years of research experience, the authors present a review of previous approaches to the study of solids transport in both drilling and well interventions with emphasis on experimental studies. An overview of the theoretical study of solids transport is presented in a companion paper (Li and Luft, 2014). The basic tests required to collect comprehensive laboratory data in support of the development of a semi-empirical theoretical model to simulate the hole cleaning process, are also discussed. To date there is still no satisfactory solids transport software model commercially available for the oil industry. This paper provides some insight into and understanding of the complexity of the solids transport process, a general guide for necessary laboratory testing and some recommendations for future research related to this subject.
Bulk Transfer on Oil Rigs: System Optimised through Pilot Testing
Authors: Ratnayake Chandana , Saasen Arild
Published: September 2014

Pneumatic conveying is a material transportation process used on nearly every offshore rig, in which bulk particulate materials are moved over horizontal and vertical distances within a piping system with the help of an air stream. Using either positive or negative pressure of air or other gases, the material to be transported is forced through pipes and finally separated from the carrier gas and deposited at the desired destination. This mode of bulk solid transportation is efficient compared to other modes of transportation because of the flexibility of installation and application on the rigs. Although pneumatic conveying has seen increased use on drilling rigs, there are still many major problems hampering its employment in a wider range of conveying applications like high energy consumption, excessive product degradation and system erosion, unstable plugging phenomena, severe pipe vibration and repeated blockages. Further, the lack of simple procedures for the selection of an optimal system, thus use of sub-optimal system are major problems in pneumatic transport system design and rig applications.

This paper presents a scientific investigation aiming to design and optimise offshore bulk transfer systems for handling of weighting materials like barite, clay type materials like bentonite and oil well cements. The approach is based on a scaling-up technique involved with pilot scale testing. Test procedures, relevant theories on gas-solid two phase flow in pneumatic transfer and results are presented in the paper. Finally, a detailed procedure on how to optimise bulk transfer on drilling rigs is presented.
The High-Temperature Electrical Submersible Pump for Production of High-Viscosity Oil Using SAGD Technology
Authors: Poshvin E. V. , Sergienko A. V. , Komarov O. V. , Tolstoguzov O. A. , Malyavko E. A.
Published: September 2014

There is a growth trend of hard-to-recover oil reserves around the world, due to the development of heavy and viscous oil. Heavy oil is becoming an essential part of the raw material base now. One of the technologies of extra-viscous oil production is steam assisted gravity drainage (SAGD) which imposes significant operating restrictions on used equipment. First of all, it is the ability of the submersible unit to work at high temperatures of the pumped liquid. Equipment testing with the establishment of its efficiency and reliability in conditions close to the real operation is a very important issue.

To solve this problem stand testing was conducted to identify the most temperature-loaded elements of serial electrical submersible pump (ESP), and the complete high-temperature ESP was designed and manufactured. The high-temperature ESP incorporates new design solutions and new materials.

To confirm technical characteristics of new ESP, tests were carried out on the stand-well for research of submersible equipment at temperatures up to 250 °C. The unit was tested in periodic mode with a total time of work 80 hours. Fluid temperature is maintained during stops not less than 160 °C and during testing - not less than 180 °C. In the course of work head-energy parameters of unit were measured, as well as the temperature on the housing of protector and motor.

Testing of the complete high-temperature ESP was successful. It allowed avoiding costly and time-consuming stage of debugging in the field conditions. The conducted work confirmed the possibility of the effective ESP utilizing for SAGD technology.
Mature Field Gas Lift Optimisation: Challenges and Strategy, Case Study of D-Field, Malaysia
Authors: Ismail W. Rokiah , Trjangganung Kukuh
Published: September 2014

As the world's population continues to grow, the energy demand is forecasted to increase directly proportional by 52% in between 2010 to 2035 (OPEC, 2013). With the oil prices predicted to be stable in the long run and expected to be as high as $165 per barrel by 2035, the search for more oil continues (OPEC, 2013). An estimation of 70% world's oil and gas production originates from mature fields with recovery at an average of 35% worldwide (Hull, 2012). This proves that there are still opportunities to recover more through enhanced primary, secondary or tertiary recovery in creating further hydrocarbon flow of a mature field.

Lower reserve with high operating and field redevelopment cost for a tertiary recovery program has deteriorate the economics for a mature field. Developing tertiary recovery for a mature field requires major modification at surface and sub-surface. Leaving the operators with the challenge to maximize recovery under current operating conditions and limited work scope of a primary recovery mainly through artificial lift method such as gas lift in oil wells.

Gas lift has been part of the primary oil recovery ever since the 1800s and the effectiveness has proven to aid the acceleration of oil recovery in a well for centuries (Gas Lift: Wikipedia, 2014). Deterioration in surface equipment and sub-surface well completion condition in a mature field, such as worsening well integrity with leaks and holes, inaccurate production metering, instability of gas compressor availability and efficiency, has resultant in the ineffective of gas lift distribution and injection downhole.

Despite the challenges faced, through prudent technical analysis and effective execution at site, the production of D-field in Malaysia has managed to increase up to 8,000 bbl/d (barrel of oil per day) instantaneously merely through production and gas lift optimization exercise.

This paper will run through the challenges faced and the technical analysis conducted in overcoming the handicap at site. This has led to the successful implementation/formulation of production philosophy and strategy to overcome challenges under different production scenarios, resulting an instantaneous production gain of some 30%. To some extent the production has been sustained and the decline arrested.
Up-to-Date and Effective Solutions for Liquidation of Accidental Oil Spills in Oil Production
Authors: Golivkin R. G. , Kuznetsov I. V. , Kornilina N. R. , Dymov I. S. , Nemov D. A.
Published: September 2014

Strict requirements to environmental safety in oil production today determinate special attention to the measures of minimization of ecological damage from emergency situations, as the consequences of several methods of accidental oil spills liquidation do not meet high demands or are not studies well.

Most of common technologies of accidental oil spills liquidation have several disadvantages. For instance, mechanical methods have low speed of response, do not manage operations with oil sludge with high viscosity level and have low portability of the equipment. They can be hardly applied in case of rugged reliefs and in different climatic conditions.

Common physico-chemical methods (appliance of sorbents) are not efficient enough as well, because they lead to accumulation of waste, require fining and waste utilization.

This article is devoted to innovative developments in the sphere of accidental oil spills liquidation and recultivation of soils and waters, which meet modern requirements.
Power Distribution in Subsea Developments: A System Engineering Perspective
Authors: Moreno-Trejo J. , Markeset T.
Published: September 2014

Subsea developments represent several technical challenges for O&G companies. The tie-back solution has been used in the industry to exploit remote fields or connect systems directly to onshore facilities or nearby existing production facilities. As it can use existing resources/facilities, this solution may save capital and operational expenses (CAPEX and OPEX). Moreover, marginal fields may become commercially viable if they are connected to an existent platform.

However, as fields are located farther away, limitations related to flow assurance, power and system distribution make it more difficult to assign resources to these projects. Systems such as power and control equipment may be located on platforms or subsea, and the choice of solutions is based on cost-saving potential, reliability and environmental care considerations. Power and control systems also have to be capable of working for long periods and functioning without interruptions. Distribution systems’ study factors also concern distance from the power source to the seabed. For longer distances, the system should be designed to repeat signals from one subsea station to another.

To explain some of the challenges and limitations for working subsea, a general description of power systems is provided. The study also discusses the role of system engineering in subsea projects and how it contributes to overcoming technical limitations and improving system performance. Good communication between all the groups is important and may reduce project errors and the need for rework.

The study discusses some considerations that should be taken into account during the concept selection to prepare the system for current and future requirements. The type of umbilical for the power and control groups is also discussed. These are used to transmit communication and power to the system.

Applications: The paper presents the role of system engineering in subsea projects. It identifies some parameters in the system and explains the technical limitations caused by loads and power requirements in subsea projects.

Results, Observations, and Conclusions: System engineering should establish strong communication between the groups working internally in the project. They provide an overall view of the system that is critical to the optimization of resources. Decisions on where to place distribution systems depend on the location of the subsea installation as the voltage drop and power loss is proportional to the distance at which the power source is located.
Development of Heavy Oil Deposits and Natural Bitumen With Small and Variable Thickness of the Formation the System of Horizontal Wells
Authors: Korepanova V.
Published: September 2014

This work is devoted to actual topic «Development of heavy oil deposits and natural bitumen with small and variable thickness of the formation in the system of horizontal wells».

This method presupposes drilling of pair of injection well and producing well over the thickness of the oil formation. Here with, producing well places under level of injection well, steam injection performs in injection well and extraction of oil performs from producing well. Changes in drilling trajectory of injection well are calculated in accordance with the mathematical model takes into account the anisotropy of oil formation. Offered method of exploitation provides creation of favorable conditions for effective exploitation of all parts of oil pool for completely deplete of it.

Heavy oils and natural bitumens classified as hard extraction of hydrocarbon feed. It has a high viscosity in natural conditions unlike light oils. That's why traditional methods of oil production is insufficiently effective in the case of heavy oils and natural bitumens. World's experience of heavy oils and natural bitumen production shows that there are wide range of methods:
The Effect of Field-Geological Characteristics Terrigenous Reservoirs on the Decrease Injectability after Well-Workover Operation
Authors: Elizaveta Soboleva
Published: September 2014

Reservoir pressure is reduced because the intensification of the selections and low compensation fluid withdrawal injection.

Engineers have made a program to increase injectability, but there is a problem. This problem is a short duration of effect it after well-workover operation (acid treatment, hydraulic fracturing).

Technological mode of injection wells and planned task is not meting.
Landing String Slip System: State-of-the-Art Design to Minimise Pipe Crushing Problems
Authors: Amezaga Federico , Rials Joseph Ross , Heidecke Karsten
Published: September 2014

New oil and gas reservoir discoveries in extreme deepwater conditions have become common. Constructing wells in these deepwater environments has challenged the industry to develop new technologies for reaching extended depths while focusing on limitations of the tubular goods due to excessive crushing loads from handling tools. To address this situation, a new landing string slip system with improved slip crushing capabilities has been designed and tested in the GOM. This hydraulically operated slip system was designed for 37 1/2-in. rotary profiles. It has a 1250-ton capacity and a pipe range of 5 1/2- to 7 5/8-in. Design considerations focused on limited maintenance, tubular guiding, and pipe centering capabilities. The main focus, however, was on reduced slip crushing forces to lessen the need of slip-proof pipe and to bring string capacities closer to tensile limitations.

To evaluate slip crushing capabilities, laboratory tests were performed on landing strings with varying wall thicknesses and yield strengths. Both strain gages and ID measurement tools were used to evaluate the slip crushing performance of this tool. The testing and results are detailed within this paper.

Applying results to field applications was the next challenge. The accepted application method is the Spiri-Reinhold equation; however, it is limited because it requires gross assumptions that do not accurately predict behaviors of critical load systems. The test data was used with the Spiri-Reinhold equation to produce a method of practical yet accurate evaluations of critical strings while highlighting important considerations for comparisons of results.

In this paper, the authors detail the operational advantages provided by this slip system, provide a comparison between the two testing methods, discuss the results obtained and their application to the Spiri-Reinhold equation, and highlight factors that must be considered when evaluating critical strings for which slip crushing forces are nearing pipe yield points.
Evaluating Gas Reserve and Project Cost Using Multistage Scenario Process on Gas Development Project
Authors: Asmoro Trian Hendro
Published: September 2014

The development phase of oil and gas fields is challenging, since wells need to be drilled and assessed for oil and gas reserves, and production facilities need to be built. It will only be executed after the exploration phase shows attractive economic indicators (IRR, NPV and payout time). Marginal gas reserves and high development costs will result in marginal economic indicators of the project compared to the company expectation.

The marginal economic indicators have created the mechanism for tight project control during project execution, in order to maintain acceptable NPV. The objective is that the thresholds of model parameters need to be defined on a staging basis to guide the project on an economical track. The thresholds will confine the limit of drilling and facilities cost which can be spent according to reserve scenarios.

The monitoring model is then built by combining the development project economics using multistage scenario tree. A solid model needs to be built and tested using Monte Carlo simulation to generate the drilling and facilities costs. Thus, the model will result simulated economic indicators which will limit of maximum allowable project cost for each reserve scenario.

This paper shows that the economic feasibility of a gas field project at the development phase can be analyzed using the multistage scenario process. Therefore, the key activity is to monitor the performance of the project, i.e. reserve verification, drilling and facilities costs, in addition to the project schedule. Finally, decisions about the project may be made at each stage according to the portfolio profile of the company.
Ichthys Field Development - Implementation of a Multi-Disciplinary Well Optimisation Workflow for a Large Gas-Condensate Reservoir
Authors: Kawasaki A. , Batiot S. , Ion A.
Published: September 2014

Optimisation of development well locations is a critical field development objective to ensure maximisation of hydrocarbon production and gas plateau duration. In a large reservoir with relatively sparse well control, significant inter-well uncertainty can exist, resulting in a high degree of subjectivity in the selection of production well locations. Following the implementation of a comprehensive workflow to construct multiple geologic realisations of the Brewster reservoir, a two-step process was developed to: 1) objectively identify optimum production well locations that suited a selected range of geologic models, and 2) subjectively refine these locations to satisfy practical requirements.

Optimum well locations were initially identified using a systematic approach covering a wide range of geologic scenarios based on an objective to maximise gas plateau duration. Resulting well locations for each realisation were then consolidated into a single well pattern using a frequency mapping technique. Subsequently, a subjective approach was adopted to refine these well locations based on considerations, including targeting of structurally high points, minimum inter-well spacing, step-out from subsea drill-centre locations, maximising the value of data acquisition (distance from existing well control) and reducing well construction complexity (minimising lateral step-out and drilling in non-preferred azimuth). Concurrently, optimisation of well geometry and total depth was investigated which indicated the potential for drilling/completion cost savings with negligible impact on predicted production performance.

The integrated, multi-disciplinary nature of this methodology was paramount in effectively communicating and satisfying well planning/execution objectives between key project disciplines.
The Coniston and Novara Development in Western Australia - Offshore Challenges met with Solutions
Authors: Sankoff Roumen D. , Di Martino Gianluca , MacDonald Shona , Marshall Craig S. , Smith Anthony
Published: September 2014

The development of heavy oil accumulations presents difficult engineering, technological and geological challenges that need to be overcome to produce economically viable projects. Even a large oil accumulation can be deemed unattractive for development in cases that combine a high cost environment with complex geological setting and unfavorable fluid dynamics. This paper highlights the challenges and presents the subsurface solutions that unlocked the value of an offshore heavy oil accumulation, 32 years after it was first discovered. Within the context of the overall development plan, the paper describes:

The design of the offshore well test that delivered 11,244 bbl/d 15.7°API oil and proved the production capacity of the reservoir and the conceptual well design. Workflow for confirming the existence of a compositional gradient and characterization of a biodegraded oil column. A novel approach to evaluation of inflow control devices (ICD) and its implementation in the well design. An ICD modelling tool developed specifically for direct comparison of different ICD geometries.

The paper also presents the field history to date – from the early failures in recovering hydrocarbons using conventional methods, through to the enabling technologies that made Coniston and Novara a viable project.
Reservoir Characterisation Using Distributed Temperature Sensing in CSG Development: Application in the Surat Basin, Queensland, Australia
Authors: Furniss J. P. , Schouten J. , Bottomley W. , Taylor H.
Published: September 2014

This paper discusses the use of distributed temperature sensing (DTS) in QGC's Surat Basin wells, and how this new technology has been used to improve reservoir characterisation through enhanced resolution of zonal productivity and flowing contributions.

In stacked reservoirs with zones of varying quality, it is vitally important to allocate production volumes to flowing zones in order to adequately characterise the reservoir and create a representative dynamic simulation model that can accurately match reservoir productivity and depletion.

For conventional oil and gas production, subsurface allocation of flowing contributions can be achieved through the use of production logging tools, which provide a measurement of volumetric flow rate and fluid density along the completed well length. The nature of Coal Seam Gas (CSG) well completions reduces the options available for allocation of flow to zones. Also, the producing characteristics of a CSG well can make this zonal allocation more complicated. Firstly, the lower zones of QGC's Surat wells are subject to higher back-pressure due to the column of water sat in the annulus, rising above the pump location. Secondly, the de-watering and subsequent de-sorption periods complicate matters, where initially 100% water flows from a zone followed by a gradually increasing gas-water-ratio: the rate of transition from water to gas production is expected to be different for each producing zone. Additionally, due to the stress dependency of coal fracture permeability during the de-watering phase, and later the impact of gas de-sorption on fracture permeability, different zones might be expected to show larger or smaller changes in productivity with time: to understand this would require repeatable measurements through the production life of wells.

In this work, DTS technology has been proven, for the first time in QGC's Surat CSG wells, as a means of achieving subsurface allocation of well test kh. This is important for the justification of permanent installations that will allow ongoing zonal allocation of produced volumes. The impact of this methodology on history match quality and reservoir characterisation accuracy is discussed. It is suggested that these new workflows could prove very beneficial in the characterisation of CSG reservoirs.
Irrigation, Straw, and Nitrogen Management Benefits Wheat Yield and Soil Properties in a Dryland Agro‐Ecosystem
Authors: Wang Shujuan , Tian Xiaohong , Liu Ting , Lu Xinchun , You Donghai , Li Shuo
Published: September 2014

Soil water, organic C, and N management practices exert strong influences on winter wheat (Triticum aestivum L.) yield and soil properties under dryland farming conditions. Here, a 9‐yr field experiment was conducted in northwestern China using treatments that included nine factorial combinations of three cultivation practices, conventional cultivation (CC), straw mulching (SM), and supplementary irrigation (SI), and three N application rates (0, 120, and 240 kg N ha−1). Relative yield gradually declined under CC and SM with N, yet remained steady under SI. Without N, yield decreased by 50 to 60%. Soil organic carbon (SOC), labile organic carbon (LOC), total nitrogen (TN), and available potassium (AK) in the 0 to 20 cm (upper) soil layer were significantly increased by SM but were unaffected by SI treatments. After wheat harvest, N application increased SOC, LOC, and TN in the upper soil layer by an average of 4.81, 20.70, and 7.61%, respectively, and decreased AK by 6.12%. The cultivation practice and N fertilizer effects on soil properties were more pronounced in upper than deeper layer (20–40 cm). At soil depths of 0 to 100 cm, nitrate accumulation under N240 exceeded 69.27% of the critical environmental risk value. Thus, SI + N120 achieved a high and stable wheat yield, and SM + N120 increased soil fertility. However, the two combinations applied over 9 yr did not meet both high soil fertility and high productivity needs. Additionally, cultivation practices with high N fertilizer are not sustainable soil management techniques in dryland regions.
Growth Habit of Rhizoma Peanut Affects Establishment and Spread when Strip Planted in Bahiagrass Pastures
Authors: Mullenix M. Kimberly , Sollenberger Lynn E. , Blount Ann R. , Vendramini João M.B. , Silveira Maria L. , Castillo Miguel S.
Published: September 2014

Planting rhizoma peanut (RP; Arachis glabrata Benth.) in strips in bahiagrass (Paspalum notatum Flügge) pastures may be an economical approach to increase sward nutritive value, decrease dependence on N fertilizer, and promote sustainable mixed‐species pastures. Released cultivars and germplasms of RP range in growth habit from decumbent to upright, differences that may affect their spread and response to defoliation in grass pastures. The objectives were to quantify initial establishment characteristics and subsequent spread of RP entries following strip planting. Treatments were the factorial combinations of two defoliation practices after planting (haying or grazing every 28 d) and four RP entries (Arblick, Ecoturf, Florigraze, and UF Peace). By the year after planting, decumbent types Arblick (51%) and Ecoturf (48%) had greater RP ground cover than upright‐growing UF Peace (34%), but they were not different in cover than the intermediate type Florigraze (40%). Haying resulted in greater cover than grazing (51 vs. 31%). Spread of RP into adjacent bahiagrass was reduced by grazing compared with haying during the year of planting (0 and 0.24 m, respectively) and year after planting (0.34 and 0.67 m, respectively). Results suggest that decumbent Ecoturf and Arblick and intermediate growth habit Florigraze can be established successfully in strips in bahiagrass pasture, and establishment is favored when swards are used for hay rather than grazing during the first 2 yr.
Personality Correlates of Aesthetic Preferences for Art, Architecture, and Music
Authors: Cleridou Kalia , Furnham Adrian
Published: September 2014

The current study investigated the relationship between aesthetic preferences and the Big-Five personality dimensions across the three domains of art, architecture, and music. A five-factor classification of artistic styles was devised which included the Sophisticated, Contemporary, Intense, Mellow, and Unpretentious factors. Participants were required to provide ratings for aesthetic stimuli representing these factors, as well as complete the International Personality Item Pool (IPIP) inventory. As was predicted, aesthetic preferences did vary as a function of personality, with Openness to Experience being, as usual, the best predictor. Preferences were consistent across the domains of art and architecture, but were inconsistent with some artistic styles in the music domain. Gender, ethnicity, and artistic experience were also found to exert some influence on aesthetic preferences. Implications, limitations, and future research suggestions are discussed.