bluuebunny/crossref_metadata_2025 huggingface dataset:
Water Use in the Oil and Gas Industries: An Evaluation of Best Practices for Communicating with Scientists, Policymakers, and the Public
Authors: Cook Margaret , Grubert Emily
Published: March 2017

Onshore unconventional oil and gas production has prompted concerns about water use and related potential negative outcomes. For industry, receiving and maintaining social license to operate depends on good communication, particularly about controversial issues like water in the oil and natural gas industries. This study presents results from interviews with experts from different backgrounds who communicate about water as it relates to oil and natural gas to investigate: what are best practice strategies to communicate about water in oil and natural gas, and what can industry learn from current practice? Focusing on the United States midcontinent and using snowball sampling, we collected information from people from different backgrounds, career stages, and sectors—including industry, legislators, regulators, academics, and journalists—about their strategies and advice. We then interviewed community members in the Eagle Ford Shale in Texas about their communication strategies and how they perceive communications for which they are the audience, with the goal of determining what strategies are most effective. Results indicate that experts communicate in many ways—meetings, presentations, workshops and town halls, publications, emails, videos, and digital media. While experts prioritize face-to-face transmissive interactions, community members prefer face-to-face exchanges supported by verifiable printed information due to distrust of many expert communicators. Defining successful communication is difficult, though, and communication training is rare. Technical or scripted answers to emotional concerns are not always accepted by audiences, though they might be prioritized by companies interested in consistent messaging. The results of our interviews indicate that industry communicators should use clear definitions, build trusting relationships, approach diverse audiences, and be open to feedback and true exchange. The results of this study should aid industry in communicating with concerned community members, academics, journalists, and policymakers about water use in oil and gas operations. Results might translate to communicating about other controversial environmental topics, as well.
Pressure Transient Analysis for Leaky Well Characterization and Its Identification from Leaky Fault
Authors: Mosaheb Mojtaba , Zeidouni Mehdi
Published: March 2017

Deep saline aquifers are considered for underground disposal/storage of fluids. Undesirable leakage of the injected fluids to adjacent layers may adversely affect underground water and/or hydrocarbon resources. Two main potential leakage pathways are identified as leaky wells and leaky faults. In recent studies, pressure transient analysis was used to characterize leakage through such pathways assuming that the pathway feature (well versus fault) is actually known. However, in general one may not know the nature of the leak. It is important to determine whether the leakage pathway is fault (planar leakage pathway) or a well (line-source leakage pathway). The flow regimes corresponding to these different features can be very different causing completely different pressure signals. In this study, we use pressure transient analysis to provide diagnostic plots to distinguish the leakage through a well from that through a fault. Our approach is based on the development of analytical models cast in the form of type curves. We use analytical models to investigate the pressure change in a system of an injection zone and an upper zone separated by a barrier layer. A method is presented based on pressure transient analysis to differentiate between leaky wells and leaky faults and to characterize the leaky well. The nature of leakage is detected using the typical type curves and finally, location and hydraulic characteristics of the leaky well are obtained.
Experimental Evaluation of Wellbore Flow Models Applied to Worst-Case-Discharge Calculations
Authors: Waltrich Paulo J. , Capovilla Matheus S. , Lee Woochan , Zulqarnain Mohammad , Hughes Richard , Tyagi Mayank , Williams Wesley , Kam Seung , Archer Alexander , Singh Jagdeep , Nguyen Hai , Duhon John , Griffith Craig
Published: March 2017

An experimental investigation was carried out to investigate the behavior of gas-liquid flows in a large-diameter pipe with high flow-rates. The objectives are to experimentally evaluate two-phase flows in vertical pipes of large diameter and collect information to verify the accuracy of wellbore flow models applied to Worst-Case Discharge (WCD) calculations.

The flow correlations developed for small diameters, used on Worst-Case-Discharge calculations, show errors of more than 100% compared to the experimental data for large-diameter pipes. However, for low gas-liquid-ratios, the there is a reasonable agreement between experimental data and simulation results for all wellbore flow models tested, with errors lower than 10%. This study uses the experimental data to provide guidance on how to improve these flow correlations and proposes how to use the flow models to obtain improved results on WCD calculations.
Processing and Recycling of Waste Flowback Fracturing Fluids in Tarim Basin, China
Authors: Huifeng Liu , Xiangtong Yang , Hongtao Liu , Kelin Wang , Zebo Yuan , Ronghuai Zhao , Yanzhi Zhang
Published: March 2017

Hydraulic fracturing is extensively used in the petroleum industry to enhance well productivity. However, the discharge of flowback fracturing fluids after fracturing brings out significant environmental challenges. Flowback fluids usually contain poisonous additives, which may cause deaths of plants and animals if discharged directly to the ground. This paper introduced an effective processing and recycling system to deal with flowback fracturing fluids in Keshen gas field of Tarim basin, China.

Apparatuses such as AA7020 atomic absorption spectrophotometer, etc. were used to test the properties of the flowback fracturing fluids in Keshen gas reservoir so as to find out which properties are needed to be processed to meet the requirements. Then various technologies of processing harmful substances in the fluids like suspended solids and high-valence metal ions were compared and selected via repeated experiments. The procedures to compound new fracturing fluids using the processed fluids were also optimized and tested. Based on the selections and optimizations, a processing and recycling system to deal with on-site flowback fracturing fluids was founded and put into operation.

The results of laboratory tests of the flowback fluid properties showed that there was more than 60% of weighing additive residual in the flowback fluid, most of which could be recycled. The contents of suspended solids and high-valence metal ions in flowback fluids far exceeded the required water quality standard for discharge, and they had to be processed to re-compound fracturing fluids. For the processing of suspended solids, the effectiveness, costs and efficiency of three methods, Chemical coagulation-sedimentation, membrane filtration and sand filtration were compared and sand filtration method was selected as the best one. For processing of high-valence metal ions, the methods of complexing stabilization, ion exchange and chemical precipitation were compared and the chemical precipitation method was selected as the most cost-effective one. After the quality of processed fluid meet requirements, the procedures of adding the other additives were also optimized to guarantee good properties of the newly-compounded fluid. A recycling system has been founded to process the flowback fracturing fluids on-site, which has a processing capability of 300m3 per day. During on-site trials, 970m3 flowback fracturing fluids have been already processed and recycled successfully, and 560m3 of fluids have been successfully used for fracturing of well KeS2-2-16.

The laboratory experiments and on-site trials have proved the feasibility of the recycling system. It reduces the volume of fluids discharged to the environment by 70% in Keshen gas field, and is expected to reduce more if the processing system is further improved. As a result, it has the potential to be popularized to relieve the environmental stress brought by hydraulic fracturing.
Utilization of Co-Produced Water from Oil Production: Energy Generation Case
Authors: Akhmadullin Ildar
Published: March 2017

Co-produced water resources in oil & gas fields raise technological interest under the condition of increased energy demand and carbon dioxide emission reduction. Primarily the development of medium and low-temperature co-produced water resources are discussed in terms of energy production and further utilization in the downstream facilities of petroleum industry. Addition of the Organic Rankine cycle (ORC) as a compact binary power plant to the existing scheme allows harvesting a great portion of energy that is usually lost as waste heat. This additional system does not interrupt the main facility streams and operational parameters. The simple case with R134a refrigerant was numerically explored for the wide range of co-produced water flow rates and temperatures. The results show that with the increase of water production the power generation is increased up to 1 MW at 50,000 BWPD and 275°F water temperature. The economic evaluation shows that the Levelized cost of electricity falls lower than 1.5 cents/kW. With using the proposed scheme on the production facility, the carbon dioxide (CO2) emissions can drop up to 500lb. per operational hour comparing with traditional gas turbine station.
The Effects of Oil Market Events on Carbon Emissions: A 2016 Case Study
Authors: Rafieisakhaei Mohammadhussein , Barazandeh Babak
Published: March 2017

Combustion of fossil fuels are the main source of man-made Greenhouse Gas (GHG) emissions. Weather it is in power generation or manufacturing industries; weather in ground transportation or aviation, wherever fossil fuels are burnt to produce energy, GHGs (particularly CO2) are emitted to the atmosphere. Petroleum products are one of the main such fuels whose market events can hugely influence the emission control strategies of the industries. In this paper, we provide an extensive model to investigate the effects of oil market variations on the volumes of the carbon emissions.

Based on the system dynamics methodology, we perform a detailed literature survey on the factors involved in carbon emissions. In particular, we find the main variables involved in the decision making process of the power generation, manufacturing, and transportation industries. We build a causal model that describes the relations between these variables and utilize the related historic data, such as for volumes of emissions by sector and resources, emission allowance price (in an Emission Trading System (ETS)), global oil price, demand and supply, and economic growth. The relations between the variables are derived using time-series analysis wherever possible and look-up tables, otherwise. The overall model is reduced to a system of ordinary differential equations that is solved using numerical Euler methods.

Our oil market model is used to simulate several possible events in the oil market that can drastically affect either demand or supply. Moreover, stochastic events are also introduced where the occurrence of changes in the main market variables and the amount of such changes follow a random walk process. Based on our analysis in the carbon emissions, it is noted that the industries can change their short, mid and long term strategies on the portfolio of the natural resources that are utilized. However, the amount of reactions indicate different elasticities based on the type of industries. For instance, power sector as the main source of carbon emissions in the EU can plan for their mid-term portfolio based on the price changes, whereas in the long-term the effect of the EU regulations and goals in terms of the carbon emission (enforced by the ETS) play a more significant role. Our simulation results confirm these findings. Moreover, a detailed case study of related oil market events in 2016 is provided whose effects are simulated in the model to show the carbon emissions changes.

A system dynamics model that combines the oil market and carbon emission model is provided and the effect of stochastic events in the oil market (that result in the oil price changes) are investigated. A case study of 2016 events are provided and possible future events are simulated to investigate the changes in volumes of carbon emissions.
Developing a Safety Culture for Remotely Piloted Aircraft Systems Operations: To Boldly Go Where No Drone Has Gone Before
Authors: Lamb Tracy
Published: March 2017

Star Trek movie fans no longer have to reach for the DVD player to have their Sci-Fi fix.

If you want to see the future, for better or for worse, look no further than the local news channel to see our ‘new world technology' interacting with our daily life. Drones, or Remotely Piloted Aircraft Systems (RPAS), are developing faster in their performance and capabilities than even the professional RPAS operators can keep up with.

The decision to ‘send in the drone', can provide safer and more efficient solutions compared to that of traditional labor intensive inspection, detection, survey and data collection methods. Across a wide range of industries, organisations are recognising significant financial and safety benefits of using RPAS, especially those companies who engage in High Risk Operations (HROs).

Humans play a vital and centric role in RPAS operations; research has indicated that this role is more complex than conventional aviation and safety critical activities such as commercial infrastructure inspections, testing and data collection. As this industry explodes like a supernova and RPAS operators become more prevalent in the commercial aerospace, we have to ask a deeper question, who is operating the system at the front line ?

The success of the emerging RPAS industry will be determined by the willingness and ability of RPAS crew and the end users to employ aviation safety philosophies, disciplines and the proven aviation safety culture model. The RPAS industry needs more than a compliance philosophy to harness success; the key to this is a positive commitment to develop an RPAS Safety Culture.

Fortunately, lessons learned from 110 years of aviation have been recognised as crucial to operational success by other safety critical industries, such as the medical, industrial, nuclear power, utilities and other industry sectors. It is now time for the application of this type of safety culture to progress into the commercial RPAS world, a new generation of Airmanship, for a new generation of aviation.
An Integrated Approach to Operational Risk Management – The Role of Process Safety Management
Authors: Neill Mike
Published: March 2017

Objectives/Scope

Operators need to manage a complex environment of operating activities, plant conditions, and working practices. All interact with each other as well as with process safety barriers, deliberately and inadvertently changing the potential for a major hazard event. With this complex range of interactions in mind, every operational decision has an element of risk. By taking a step back to look at how these interactions and process safety are managed across the planning-to-execution business processes, there is big opportunity to not only reduce risk but improve the productivity of operations.

Ultimately, Operators need to make risk mitigation arising from Process Safety Management (PSM) systems an integral part of efficient and effective daily operations.

Methods, Procedures, Process

Process safety deviations and non-conformances are often assessed and managed in different ways, by different functions. Furthermore, operational risk data is often stored and managed in multiple places. As a result, many key decisions can be made unaware of the major accident hazards arising from deviations as well as the interaction between deviations and daily operations. The absence of a consistent way to understand and mitigate the combined impact of risks to frontline operations adversely affects operational performance as well the overall risk profile. Operators need to employ a common means of balancing risk against productivity, so everyone across the business can make better operating decisions.

Arguably, Process Safety Management (PSM) has the greatest potential to affect major accident risk. As such, it is essential to capture the residual risk arising from each deviation in a transparent and common to understand the overall cumulative risk arising from deviations.

By placing PSM risk in the context of daily operations, PSM can become a powerful driver of operational performance.

Results, Observations, Conclusions

By capturing all activities, performance deviations, and non-conformances in terms of the risk they carry to the business, operators can build a holistic picture of operational risk. This approach makes the impact of PSM deviations on safety and operational performance clear for all to see, and it enables plant operators to improve their planning, maintenance, and work execution.

Rather than implement a new process safety model or an additional safety model, organizations are enabling a common language of risk to ensure that operational risk mitigation becomes an integral way of achieving efficient and effective operations. Through this, organizations are able to understand their levels of major accident hazard risk in a dynamic real-time view. This new approach allows organizations to better understand the cumulative risk they are carrying at any given time which can be used to improve long-term operational decision making, and achieving overall operational excellence.

Novel/Additive Information

N/A
Restoration of Reservoir Cores to Reduced Reservoir Conditions for Chemical EOR Studies: Impact on Mineralogy, Pore Structure and Rock/Fluids Interactions.
Authors: Guillon Valentin , Kohler Eric , Wartenberg Nicolas , Rousseau David
Published: March 2017

Reservoir rock samples available for chemical EOR studies are often not preserved. It is well known that wettability has to be restored by appropriate protocols. Some authors showed that rock samples should also be restored with respect to redox mechanisms, in particular in view of EOR studies involving polymer and surfactants. This could mainly be achieved by using reducing fluids removing the iron oxides formed at the surface. Still, the impact of such reducing fluids on minerals and pore structure is unknown. In this paper, we analysed the impact of various reducing fluids on a complex Bandera brown sandstone outcrop containing minerals present in many sandstone reservoirs.

The sandstone mineralogical composition and petrophysical properties were at first fully characterized by classical core analysis, XRD and SEM measurements. This rock was found to contain high amount of clays such as kaolinite and chlorite, few feldspars, calcite cement and iron oxides. Reducing fluids were taken from literature and used to reduce rock surface to various extends. Impact on mineralogy, pore structure as well as on surfactants adsorption were evaluated by static and dynamic adsorption measurements and XRD/SEM analysis.

Main results have shown that rock mineralogy was impacted by reducing fluid, resulting in calcite cement dissolution. Depending on the presence or not of chelating agent, iron and calcite solubilized by the reducing fluid were sometimes shown to re-precipitate in the core (iron precipitating with sulphur under pyrrhotite form). Pore structure was hence strongly impacted by those dissolutions and precipitations.

A limited decrease of adsorption of surfactants was observed after reducing treatment. It is still unclear if this decrease is due to iron reduction or to calcite dissolution. Reducing fluids used were found to be unable to reduce rock surface while preserving pore structure and mineralogical composition of rock. It is then still unclear that reduced state has to be restored whereas it is clear that such fluids should not be used without studying their impact on mineralogy and pore structure.
An Enhanced Nonlinear Analytical Model for Unconventional Multifractured Systems
Authors: Molina Oscar , Zeidouni Mehdi
Published: March 2017

One of today's challenges in reservoir management of liquid-rich shales is to forecast production performance based on rate/pressure transient analysis. The need of large pressure gradients to produce from shale reservoirs through multifractured horizontal wells (MFHW) can induce considerable changes in rock and fluid properties that can largely affect the bottom-hole pressure behavior with time and consequently the accuracy in the prediction of well performance. Therefore, the assumption of constant properties in shale reservoirs may not be safe when modeling MFHWs performance. This paper presents an analytical model for MFHW that accounts for pressure-dependent rock and fluid properties by the application of a modified pressure to the five-region model (Stalgorova and Mattar, 2013) which can be easily inverted to get an analytical solution to the nonlinear problem in terms of pressure. The validity of the proposed MFHW performance model is compared against data obtained from numerical simulation for several case studies. We observe that our analytical solution accurately captures bottom-hole pressure behavior and gives an excellent estimation of depletion time under a certain restriction. Furthermore, we find that nonlinear diffusion processes in liquid-rich shales, for which pressure-dependent rock and fluid properties are given in exponential form, can be fully described by using the Porous Medium Equation (PME). We present a straightforward application of the PME to predict flow regimes (fast diffusion, normal diffusion or slow diffusion) and the excess energy gained or required to keep a constant production rate in MFHW undergoing nonlinear diffusion; however, the application of the PME to the five-region model is not forthright and remains a matter of future development.
Next-Generation Supramolecular Assemblies as Displacement Fluids in EOR
Authors: Yegin Cengiz , Jia Bao , Zhang Ming , Suhag Anuj , Ranjith Rahul , Balaji Karthik , Peksaglam Zumra , Thanon Diyar , Putra Dike , Wijaya Zein , Saracoglu Onder , Temizel Cenk
Published: March 2017

Current analyses indicate that 50% of oil produced in USA and the world will be through EOR technologies in the next 20-25 years, and heuristics suggest that polymer flooding should be applied in reservoirs with oil viscosities between 10 and 150 mPa.s. The key factor limiting the recommended range is that for oil viscosities greater than 150 mPa.s, where injected water viscosity values required for a favorable mobility ratio give rise to prohibitively low values of polymer injectivity and pumping efficiencies. Herein, we propose that a novel type of supramolecular system based on the complexation of long chain amino amides and maleic acid with reversibly adjustable viscosities can enable us to overcome the injectivity limitation.

The concept is that viscosity of the injected supramolecular system will be maintained initially at low values for easy injection and pumping, and then increased by means of an external pH stimulus just before or upon contacting oil. Our promising lab-scale preliminary studies have indicated that such supramolecular systems possess not only reversible pH-responsive properties, but are also very tolerant to high salinities and temperatures.

While polymers degrade and break up upon experiencing sudden extreme shear stresses and temperatures, supramolecular solutions merely disassemble and re-assemble. Therefore, supramolecular solutions can be considered as healable polymer solutions in a way. Supramolecular solutions can adapt to the confining environment. For instance, when a high molecular weight polymer macromolecule is forced to flow into narrow channels and pores, molecular scission processes may take place.

Supramolecular solutions can have a significant impact in the cases where thermal methods cannot be used for some viscous oils due to thin zones, permafrost conditions and environmental constraints. This project is primarily aimed at developing novel supramolecular assemblies with adjustable viscosity and interfacial properties that have robust tolerance against high temperatures and salinities. Such supramolecular assemblies will be used to significantly improve the feasibility and cost-effectiveness of displacement fluids used in EOR. Overall, there is a significant potential for application of supramolecular solutions in the US and throughout the world.
Step Rate Test as a Way to Understand Well Performance in Fractured Carbonates
Authors: Shchipanov A. , Kollbotn L. , Prosvirnov M.
Published: March 2017

Step Rate Test (SRT) is commonly used to estimate formation parting (or fracture opening) pressure for stimulated wells. SRTs may also focus on changes of well performance at different rates / pressures that is of special interest for stress-sensitive reservoirs such as fractured carbonates. Installation of permanent downhole gauges (PDG) and running SRTs on injection wells at the Ekofisk field gave a chance to improve the understanding of reservoir and well performance. Analysis of these SRTs also resulted in further development of SRT interpretation techniques.

An approach to SRT interpretation, combining analytical pressure-rate (p-Q) curve analysis and step-by-step Pressure Transient Analysis (PTA) with numerical simulation of SRT, was suggested and tested. Applying this approach to Ekofisk SRTs has shown that the p-Q analysis may be used for diagnostics of well performance changes, while step-by-step PTA enables decomposing of well (skin factor) and reservoir (conductivity) effects with estimation of corresponding well-reservoir parameters as pressure or rate functions. Numerical simulation confirmed that pressure dependent conductivity estimated from the step-by-step PTA is the governing factor in matching SRT history.

Special attention was paid to the uniqueness of SRT interpretation using suggested approach. Reaching infinite acting radial flow (IARF) regime at each step of a test provided unique parameter estimates as shown by example of a stimulated slanted injector. Being too far from IARF at end of each step will make the interpretations more uncertain. Different sets of changing parameters estimated from SRT interpretation could provide satisfactory match in numerical runs as was illustrated by example of a horizontal injector with multiple induced fractures. Comparison of interpretation results for different wells integrating additional field data is a possible way to reduce this uncertainty.

Finally, some hints to designing, conducting and interpreting SRTs of different types of wells in fractured carbonate fields are given, using Ekofisk field experience.
Capillary Pressure in Nanopores: Deviation from Young-Laplace Equation
Authors: Li Bo , Bui Khoa , Akkutlu I. Yucel
Published: March 2017

Recent studies on multi-phase fluids in nanoscale capillaries indicated that the capillary wall-fluid interactions could play a dominant role on the co-existence of the phases, which may change the fundamental properties of the fluids, such as density, viscosity, and interfacial tension. At the extreme of the confinement, these properties become vague. This raises a serious question on the validity of Young-Laplace equation to predict capillary pressure in small capillaries that the unconventional resources commonly exhibit. In this paper, using nonequilibrium molecular dynamics simulation of mercury injection into model nanocapillaries, the nature of multi-phase fluids is investigated in capillaries with sizes below 20nm, and the Young-Laplace equation is re-visited.

Higher capillary pressure is predicted for the model nanocapillaries used in the simulations compared to that value obtained using the Young-Laplace equation, in particular, when the capillary diameter is less than 10nm. Good agreement found with the theory in larger size capillary. The capillary pressure increases as the capillary size is decreased and shows a power-law dependence onthe size of the capillary. This dependence yields up to 70% increase in the estimated capillary pressure value for the extreme case of 1nm capillary. Higher tangential local pressures at the nanocapillary entry resulted from the adsorption phase is the cause of the difference.

Based on the observations, a modified Young-Laplace equation is proposed for mercury-airfilled pore systems which are commonly used in Mercury Injection Capillary Pressure (MICP) experiments for the pore volume and pore size distribution measurements. At the highest injection pressure of MICP, the minimum captured size is predicted 4.8nm instead of 3.6nm based on the Young-Laplace equation. The increase in the predicted capillary size leads to an increase in total pore volume of the sample. The error in volume is up to 20% for measurements with shale samples. The results are important for the characterization of resource shale formations because the nanopore volume correction influence the hydrocarbon in-place and reserve calculations.

The work can be extended to other multi-phase systems, such as oil-water, and water-gas, grouping with other capillary wall material to study the behavior of multi-phase flow in nanocapillaries.
Development of a Parallel Simulator Utilizing Multiple Interacting Continua and Embedded Discrete Fracture Models in Fractured Unconventional Reservoirs
Authors: Wang Kun , Liu Hui , Luo Jia , Chen Zhangxin
Published: March 2017

Unconventional petroleum reservoirs, such as shale gas and tight oil reservoirs, have changed the entire energy equation in the world. An accurate and efficient reservoir simulator is essential for the development and management of these reservoirs and the optimization of their production schedules. However, the gas storage and transport mechanisms in ultra-tight matrix, including gas adsorption/desorption, non-Darcy flow, and surface diffusion, are different from those in conventional petroleum reservoirs. In addition, hydraulic fracturing techniques are often required to achieve their economical production, which leads to existence of complex fracture networks in the unconventional reservoirs. These features of unconventional reservoirs make their accurate numerical simulations a big challenge. In this paper, we develop a simulator for fractured unconventional reservoirs, which takes the specific gas storage and transport mechanisms into consideration, employs a multiple interacting continua (MINC) model to handle well connected natural fractures, utilizes an embedded discrete fracture model to simulate large-scale disconnected hydraulic fractures, and uses a coupled model to efficiently describe multi-scale fractures with irregular geometries. To reduce the computational time, parallel computing techniques are also employed, with which large-scale reservoir simulation cases can be finished in practical time. From the numerical experiments, we can see that reasonable physical phenomena is captured and accurate predictions are performed by this simulator.
Shale Gas Well Total Fracture Surface Area Calculation Re-Visited for a Dynamic Formation Permeability
Authors: Soni Laura Pelaez , Akkutlu I. Yucel , Maggard J. Bryan
Published: March 2017

Shale gas wells exhibit formation linear flow, which is in most cases the only transient flow regime available for engineering analysis. Production Rate Transient Analysis (RTA) methods have been developed to analyze the transient flow into shale gas well. These methods often assume homogeneous reservoir properties and neglect the dynamic nature of the formation. In shale gas reservoirs, however, the properties could change; in particular, the permeability due to stress-dependence of the formation and non-Darcian effects. In this work, a theoretical study is conducted to show the range of errors on the predicted total fracture surface area caused by the constant permeability assumption. The study proposes a modified RTA model, which accounts for dynamic permeability to eliminate the error in calculated area.

Results from the sensitivity analysis show that the error on surface area calculation ranges from 1% – 323% due to the constant permeability assumption. The total fracture surface area calculation is most sensitive to the geomechanical (stress-sensitive) parameters, which affect the permeability in the region away from fractures. Results show that the error in area is reduced when the initial value of the dynamic permeability is large. Sorption parameters are the second most influential category affecting the surface area calculation. Molecular diffusion of the adsorbed and free gas molecules enhance permeability near the fractures, wherein the slightest variations in dynamic permeability can cause the error in area to change significantly. For these parameters, higher permeability near the fractures translates to higher error in area.
Seismic History Matching Using a Fast-Track Simulator to Seismic Proxy
Authors: Geng Chong , MacBeth Colin , Chassagne Romain
Published: March 2017

In this paper we propose a proxy model based seismic history matching (SHM), and apply it to time-lapse (4D) seismic data from a Norwegian Sea field. A stable proxy model is developed for generating 4D seismic attributes by using only the original baseline seismic data and dynamic pressure and saturation predictions from reservoir flow simulation. This method (MacBeth et al., 2016) circumvents the petro-elastic modelling with its associated uncertainties and also the need to choose a seismic full-wave or convolutional modelling solution, which are used in conventional simulator to seismic (sim2seis) modelling. The method is tested on an offshore field case study from the Norwegian Sea.

In this study we firstly perform a check on the validity and accuracy of the proxy approach following the methodology of (Falahat et al. 2013) as a guide. The results confirm linear superposition between the pressure and saturation effects controlling the seismic data. Next a quasi-history matching is set up - here simulation model realisations are selected by random assignation of the key parameters to define a walk through solution space. After this, both the sim2seis and proxy modelling approach are compared for each realisation against a known reference case. The results show a mean seismic error of lower than 5%, which indicates the possibility to utilise a fixed proxy to model the 4D seismic. Finally, the full seismic history matching loop is implemented, where the sim2seis and the proxy-driven SHM are launched to find the optimal solution for our field. A particle swarm optimization (PSO) algorithm is applied as the optimisation tool, and only seismic data are used in the objective function. In both cases the algorithm converged after 30 iterations, and the optimal solutions of the two schemes are comparable. It is observed that the full sim2seis and proxy-driven SHMs are only marginally different, implying that solution space is similar in both cases. We also observe that in either case, matching to seismic data only can improve the production match. A unique feature of this study is the application of a seismic modelling proxy in the SHM scheme. Despite its relative simplicity, the approach is found not to bias the optimal solution of the more conventional SHM where the full physics of seismic modelling is applied. Meanwhile, this approach can save over 60% of the total computing time compared with the normal procedure, and this helps significantly to achieve a rapid and effective seismic history matching and better define uncertainty with a larger number of realisations.
Conformance Control Using SMG Microgels: Laboratory Evaluation and First Field Results
Authors: Zaitoun Alain , Dupuis Guillaume
Published: March 2017

SMG Microgels are pre-gelled polymers having a narrow size distribution and behaving like large polymer molecules. Their stability is strongly enhanced by internal cross-links. Several SMG microgels having different chemical compositions and cross-link density, with a size of around 2 μm were submited to laboratory corefloodtests. SMG propagation in reservoirs is driven by a size exclusion mechanism. Microgel size prevents invasion of low permeability zones and creates flow resistance in high permeability zones by adsorption on the rock. The permeability cutoff can be tuned by microgel size and chemistry. Permeability reduction generated by SMGs is determined by the thickness of the adsorbed layer which is roughly the size of the microgel in solution. It is little dependent of the adsorption level. Adsorption depends on the chemical composition of the microgel and on the nature of the rock.

An SMG Microgel with soft consistency was selected for a Conformance Control field application in a heterogeneous sandstone reservoir. Reservoir permeability ranges between 10 mD and 1200 mD with an average permeability of around 200 mD. The pattern consists of one injection well surrounded by eleven offset producers. The injection lasted 3 months with a total volume of 9,000 m3. After a few months, six offset producers showed increase in oil rate along with a reduction of a few points of water cut. One well lost both water and oil, thus proving diversion to the other wells. The trend remains steadily established in the pattern with continuous increase in additional oil production. After two years, more than 33,000 bbl of additional oil has been produced, giving a ratio of less than 0.7 lb of microgel per extra barrel of oil.
Harsh Environment Logging-While-Drilling Tools Enhance Well Performance in North Sea HPHT Wells
Authors: Lunney Iain , Duriez Alban , Solbakk Tommy , Skaug Mats Bjørndal , Brian Tom
Published: March 2017

Increases in high pressure, high temperature (HPHT) drilling campaigns on the continental shelf of Norway and the UK have increased demands for next-generation technology that can deliver borehole measurements, enabling the wells to be drilled and reducing the operator's risk and operational expense. These deep gas development and exploration wells require a dramatic departure from conventional operating envelopes, including pressure, temperature, hydraulics, and formation evaluation capability. This paper discusses unique borehole integrity and formation evaluation challenges in two North Sea HPHT wells. It demonstrates how innovative new technology, coupled with fast-track component design modifications to meet specific operational challenges, enabled the safe, cost-effective drilling of these wells.

The development of telemetry, gamma ray, pressure-while-drilling (PWD), vibration, and induction resistivity technology that is rated to operate at 200°C / 25,000 psi followed a stringent life cycle process. In this process, the field trial phase of the technology development included a rapid phase of trial runs, followed by engineering improvements. This iterative process helped to ensure that the technology was fit-for-purpose when it reached the commercialization phase.

The step change in the thermal tolerance of the downhole electronics was accomplished through significant changes in design simplification, thermal screening, ceramic encapsulation, and thermal dissipation modeling relative to existing high-temperature electronics rated to 175 °C.
Statistical Analysis on Nutritional Status and its Associated Factors of Under Five Years Children in Nepal
Authors: Upadhyay Hari Prasad , Bhusal Madhav Kumar
Published: March 2017

Malnutrition among under five year of age group is a major underlying cause of the child morbidity and mortality in many developing countries like Nepal. Nutritional status of children is a proxy indicator for assessing the health status of entire population. This study was carried out to evaluate the nutritional status of the most vulnerable age group of children (0-59 months) and to identify different factors associated with it. Generally three anthropometric indicators were often used to assess the nutritional status of children height-for-age, weight-for-height and weight-for-age. This study is based on data of Nepal Demographic and Health Survey. WHO Anthro software and IBM SPSS 20 were used to analyze the data. The prevalence of the malnutrition (stunted, wasted and underweight) was found in the different aspect. This study consists of 2334 children of under five years age groups, out of this 50.9% were male children and 49.1% were female children, the prevalence of the stunted is 41%, wasted 29% and underweight 11%. The prevalence of diarrhea during the data collection period is 13.80% and prevalence of fever during the data collection period is 18.70%. The statistically significant factor were body mass index of mother, wealth index, size of child at birth and education of mother and smoking habit of mother. Malnutrition (stunted, wasted and underweight) still remains as a major health problem in our country Nepal. So, our government should be focused on those factors which are significantly associated with malnutrition like health care during pregnancy period, education of mother etc. Significant number of under-five children’s of Nepal was malnourished. Maternal factors have significant association with nutritional status of the children which include extra diet in pregnancy and lactation, iron supplements in pregnancy, exclusive breast feeding for six months.
Estructuralismo y desarrollo económico regional: contabilidad social en Cartagena de Indias
Authors: Gómez Acevedo Kathy , Escobar Álvaro Andrés
Published: March 2017

La Escuela Estructuralista tuvo importantes implicaciones en el ámbito de las política públicas orientadas a promover estrategias de desarrollo económico hasta la década de 1970, con particular presencia en América Latina. Una de sus principales características es el estudio de las estructuras económicas y de las instituciones de la economía. Para tal fin, las Matrices de Contabilidad Social se emplean como metodología esencial previa a la construcción de modelos económicos siguiendo los trabajos desarrollados por Defourny y Thorbecke (1984), Stone (1985), Adelman,Taylor y Vogel (1987), y Round (2003). Bajo esta metodología, los resultados para el caso de la ciudad de Cartagena de Indias, indican la importante influencia del sector Gobierno en el dinamismo de la economía local.
Making the Sustainable Development Goals work.
Authors: Vaggi Gianni
Published: March 2017

El logro de los 17 Objetivos de Desarrollo Sostenible aprobados por la Asamblea General de las Naciones Unidas en 2015 dependerá en gran medida del funcionamiento del último objetivo: “Asociación global para el desarrollo sostenible”. El documento sugiere que el punto principal para una asociación global efectiva debería ser el reequilibrio del poder de negociación de las diferentes partes interesadas. De esta manera, en la sección I se describen brevemente algunos cambios en la noción de desarrollo y cooperación desde 1950. En la Sección II se describe el proceso que ha conducido a los ODS y a la idea de cooperación como asociación mundial. La sección III se centra en dos grandes cambios económicos que han tenido lugar desde la década de los setenta: el crecimiento económico en Asia y el auge de las finanzas internacionales. Ambos hechos tienen enormes implicaciones para los ODS y para la asociación global. La sección IV presenta tres pasos que podrían ayudar a implementar la “asociación global para el desarrollo” de acuerdo con elprincipio de reequilibrio. Los países en desarrollo necesitan más espacio político, especialmente en sus políticas comerciales y fiscales.
Lo que el dinero no puede comprar. Los límites morales al mercado
Authors: Acosta Castro Juan Gabriel
Published: March 2017

El libro Lo que el dinero no puede comprar. Límites morales al mercado del Profesor de Harvard Michael J. Sandel es una invitación a considerar hasta dónde estamos dispuestos como sociedad a dejar que los principios económicos determinen la forma en que las relaciones personales deben desarrollarse, y si estamos dispuestos a asignarle un precio a todo, es decir, a la vida, a la amistad o al honor, por citar algunos ejemplos. Esta reseña tiene por objeto mostrar la forma en que el autor explica esta idea, utilizando situaciones que podrían parecer absurdas o inaceptables, pero que son cada vez más frecuentes en sociedades que se resisten a ser de mercado y que quieren levantar una frontera entre lo que se puede o no comprar y vender.
TEN THESES FOR THE PROGESSIVE FORCES IN THE CONTEXT OF THE EMERGENCE OF P2P AND COMMONS DYNAMICS AND THE END-GAME OF CLASSIC NEOLIBERALISM
Authors: Bauwens Michel
Published: March 2017

The emergence of radical right populism shows the end game of classic neoliberalism is in sight, and a new regime is in preparation. In this context, we need to know what the forces are that propel the victories of the Trump movement, and what progressive forces can do, especially in the context of the emergence of peer to peer and commons dynamics. The following is a short summary of such positioning, in the form of ten theses.
SMART CITIES, INTERNET OF THINGS AND PERFORMATIVE SENSIBILITY. BRIEF ANALYSIS ON GLASGOW, CURITIBA AND BRISTOL’S INITIATIVES
Authors: Lemos André
Published: March 2017

Smart cities initiatives are based on strong narratives fostered by companies and governments to deploy digital technologies in a way to improve economic growth and sustainability, as well as to maintain a better control, surveillance, and efficient usage of urban resources. It is a mix of business innovation, technocratic discourses, big data and internet of things hype. Many projects are currently being carried out and celebrated around the globe. With Internet of Things (IoT) and Big Data deployment in the core of Smart Cities initiatives (digital things, algorithms, operational systems, control rooms…), we now have to deal with a new feature of objects: their performative sensibility. Based on my observation of three smart cities initiatives (Glasgow, Curitiba, and Bristol), I would like to point out to a specific issue on the social and political dimensions of objects’ invisibility in everyday life. I propose here a very preliminary theoretical background in order to analyse the public participation and the object's invisibility in those cities. I’ll put a strong emphasis on the Internet of Things and the changing in the nature of objects. In my preliminary analysis, informational-enhanced objects are not clearly in "handiness". This invisibility is in the core of the "algorithm governmentality".
CAMBIO DE LAS INSTITUCIONES PARA EL DESARROLLO
Authors: Vázquez Barquero Antonio
Published: March 2017

Existe un amplio acuerdo sobre que el funcionamiento de las instituciones determina la evolución de las economías y la senda específica de crecimiento de las ciudades y países; es decir, que las normas y reglas, formales (como los contratos y los acuerdos entre empresas y actores) pero también informales (como los códigos de conducta y las convenciones), existentes en cada sociedad, juegan un papel estratégico en los procesos de desarrollo. Las empresas y las organizaciones toman sus decisiones de inversión en un entorno institucional y las realizan a través de un sistema de relaciones e interacciones con otras empresas y organizaciones, que forman el sistema institucional, lo que afecta a los resultados de la inversión, y, por lo tanto, al comportamiento de la productividad y al propio proceso de desarrollo económico (Vázquez Barquero, 2005).
LOS FONDOS DE CONTRAPARTIDA: MECANISMOS PARA EL FINANCIAMIENTO DEL DESARROLLO LOCAL
Authors: Mirna Benavides Blanca
Published: March 2017

El presente artículo está basado en una sistematización de cinco experiencias de alianzas multisectoriales en El Salvador: Los Fondos de Contrapartida, localizados en los municipios de Soyapango y Mejicanos, en el departamento de San Salvador; Quezaltepeque y Santa Tecla, departamento de La Libertad; y, Acajutla, Sonsonate. ...