bluuebunny/crossref_metadata_2025_split huggingface dataset:
Less is More: an Objective/Cost-Driven Approach to Reducing Uncertainty in the Appraisal of the Lam Reservoir, Central Yemen
Authors: Sellar Christopher , Zabalza Isabelle Amaya , Miguel Karina 
Published: December 2014

Abstract
This paper presents a cost versus knowledge-gained appraisal strategy for reducing uncertainty in a tight sandstone reservoir within a short timeframe. More uncertainty should not necessarily demand more data acquisition, rather an approach that focuses on answering the big questions first.
In the Shabwah Basin of central Yemen, sands from the Upper Jurassic Lam Member form fine-grained turbidite lobes. These tight sands, encountered while drilling to the Block S2 Basement reservoir, are currently undergoing appraisal as a potential unconventional oil resource. The presence of oil on surface correlates well with direct and indirect indications of natural fractures during drilling and wireline logging. In contrast, fluid sampling of thin hydrocarbon-bearing sands identified by magnetic resonance tools have so far been unsuccessful. Two possible production mechanisms have been identified in this sandstone reservoir: production from natural fractures and/or production from tight sands by hydraulic fracturing.
The carefully risked appraisal strategy will target the key reservoir uncertainties, productivity and production mechanism, using three kinds of well re-completions: testing production from a well with natural fractures (with or without frac’ing), frac’ing and flowing a well with hydrocarbon-bearing tight sands and, drilling a slanted sidetrack well to increase exposure to natural fractures, with or without frac’ing.
The appraisal approach is objective driven, not a wide-ranging data acquisition programme. There are many unknowns in the reservoir but this project focuses on reducing uncertainty efficiently by prioritising answers to the key objectives which are productivity and the production mechanism.
A decision-tree based appraisal strategy has been developed with clearly defined exit points to control the cost of appraisal versus the value of information gained from the re-completion and drilling activities. This innovative, business-driven approach to reservoir appraisal maximises early uncertainty reduction by the most cost effective methods and can be used as a model for appraisal and early development projects in the industry.
Introduction
The Lam Member is an appraisal target for a hydraulic fracture campaign in Block S2 Yemen. The exploitation of this poor quality reservoir faces many challenges, which are approached in a carefully risked way to maximise the value of information gained while minimising financial exposure to stakeholders.
Geological background
The Lam Member of the Madbi Formation was deposited within the Shabwah sector of the Sab’atayn Basin on the southern part of the Arabian Plate during the late Jurassic (Figure 1).
The Application of Very Large Numbers of Pseudo-Wells for Reservoir Characterisation
Authors: Connolly Patrick , Hughes Matthew 
Published: December 2014

Abstract
We describe a method to invert seismic data by matching to large numbers of pseudo-wells. Pseudo-well construction is based on lithofacies micro-layering constrained by a model for the vertical statistics. Elastic properties are derived from a rock physics model. We match either to single or multiple angle-stacks using synthetics based on extended elastic impedance. This is a joint inversion process as it simultaneously accounts for both elastic parameters and reservoir properties. Both localised means and standard deviations of reservoir properties are estimated.
We do not include priors for lateral statistics but instead we envisage this process forming the first step of a two stage workflow with the output providing constrains for geostatistical modelling in the second stage. With no constraints on lateral correlation the first stage can operate in 1D greatly decreasing computational requirements.
We show examples of application to two fields; one offshore Angola and the other offshore West of Shetlands. These demonstrate the quality of the algorithm which provides laterally stable results, high signal-to-noise modelling of the seismic and accurate blind well predictions.
A Novel Methodology for Estimation of In-Situ Relative Permeabilities from Wireline Formation Tester Data in an Abu Dhabi Carbonate Reservoir
Authors: Cig Koksal , Kristensen Morten , Thum Sebastian , Ayan Cosan , Mackay Eric , Elbekshi Amer , Naial Radwan 
Published: December 2014

Abstract
A multilayer carbonate reservoir, having medium to low permeabilities with distinctive oil-water contacts, is in an appraisal stage. Large data gathering including rigorous coring is underway in the field. It is identified that the slowest part of the data evaluation is generally SCAL analyses due to its laborious workflow. A new approach is proposed by introducing a wireline formation tester (WFT) multiphase flow analysis to obtain relative permeabilities. The WFT tool is commonly used in this field to measure pressures and collect samples. In this paper we present a novel methodology for estimating in-situ relative permeability curves with the help of available WFT multiphase flow data and its numerical optimization.
During drilling of a well the formation is exposed to mud filtrate invasion. The invasion displaces oil in the vicinity of the wellbore, much like a small water flooding experiment in the case of immiscible mud filtrate and formation fluid. A WFT sampling operation in a multiphase flow environment provides an opportunity for determining related properties by utilizing bottom-hole pressure and water-cut data. A numerical model replicates the mud filtrate invasion and sampling with reservoir properties and WFT tool geometry. The numerical simulation model consists of a proper definition of reservoir properties as well as WFT tool geometry, including size and shape of flow inlets, along with tool storage and fluid segregation effects. The model is embedded in an optimization workflow and relative permeability curves, damage skin and depth of mud filtrate invasion are then estimated by minimizing a misfit function between measured and modeled pressures and water-cuts. The relative permeability curves are parameterized using industry accepted models. The optimization workflow uses a distribution function of response parameters where the entire parameter range is included in the numerical runs, thus ensuring that a global optimum is found. Initial parameter estimates are determined from open hole logs, such as resistivity, dielectric, magnetic nuclear resonance and from pressure transient analysis.
The methodology developed in this paper is validated by application to a synthetic dataset with a known solution, and it is subsequently demonstrated on actual field data from a WFT sampling operation. The results of this paper demonstrate that it is possible to reliably estimate multiphase flow properties from WFT sampling data. The key contributions of this study are to show the capability of estimating a variety of multiphase flow properties from routine WFT cleanup data and to establish an automated approach, including a novel inversion methodology, to reduce the turnaround time.
New Frontiers for the Prevention Of Major Accidents and Catastrophic Oil Spill Release: a Successful Synergy of Consolidated Approaches and Innovative Methodologies to Enhance Oil Spill Preparedness and Emergency Response
Authors: Petrone A. , Scataglini L. , Buffagni M. , Aiello G. , Cianfanelli M. , Di Muzio D. , Borello L. , Sordini E. , Faraoni G. , Salvador C. , Giusto M. , Catalano R. , Cherubin P. , Antico L. , Bonuccelli M. , Bandini R. 
Published: December 2014

Abstract
The Oil and gas industry is a risky business: e&p activities have the potential to give rise to major accidents such as Blow Out events, as well as hydrocarbon leaks and also catastrophic pipeline/ riser release leading to fire and or explosion. These dramatic events can result in loss of human lives, severe pollution to the environment, damage to the asset and production disruption, and in additional to the emotional and ethical impact can seriously compromise company reputation.
On top of that, in recent years another critical challenge is posed by e&p activities in sensitive and hostile environment that represent the new frontier of development: in fact the increasing hydrocarbon demand pushes operators towards unconventional deposits and higher-risk and remote areas characterized by social and environmental sensitivities where the emergency response and the oil spill preparedness become particularly difficult.
This paper describes the successful synergy of some consolidated methodologies and new initiatives undertaken within our Company to foresee consequences of major accidents and enhance emergency response and oil spill preparedness in e&p operations: –a new procedure for the evaluation and prevention of the exposure to pollution of e&p wells that foresees the identification of exposure to pollution classes (High, Medium, Low EtP), for different typologies of wells;–the development of SMART GIS project, a web application to acquire data source information to support emergency management and oil spill preparedness;–the combination of in house Short Cut Model (SCM)iiiiii in BART tool for an expeditive estimation of Blow Out consequences;–the development of an expeditive semi-quantitative methodology to assess risk of release from pipeline combined with a Bow tie approach for the identification of preventive and recovery barriers to reduce frequency of hazardous event or mitigate their consequences.
Transition Zone Behaviour: The Measurement of Bounding and Scanning Relative Permeability and Capillary Pressure Curves at Reservoir Conditions for a Giant Carbonate Reservoir
Authors: Spearing M. C. , Abdou M. , Azagbaesuweli G. , Kalam M. Z. 
Published: December 2014

Abstract
Significant reserves are held in the transition zone of an Abu Dhabi carbonate reservoir, but uncertainty exists in how relative permeability (kr), capillary pressure (Pc) and residual saturations vary with initial water saturation throughout the column. A study has been undertaken to provide an improved understanding of the water flood recovery and remaining oil saturation distribution within the transition zone by better definition of the scanning kr and Pc curves. Primary drainage, and imbibition from irreducible water saturation were measured for both kr and Pc to provide the "bounding" data. Imbibition kr and Pc curves were then measured at three higher initial water saturations up to 0.60PV. The semi dynamic method was used for Pc measurements and steady state method for kr. All tests were performed with live reservoir fluids at full reservoir conditions with in-situ saturation monitoring (ISSM). Drainage curves are often measured in the laboratory with refined oil and then aged with live crude oil at Swirr. This may not truly reflect the reservoir wetting conditions and so in this study both the primary drainage kr and Pc measurements were performed with live reservoir crude oil. During the drainage tests an ageing period was allowed at each progressively higher oil saturation as new regions of the pore space were exposed to crude oil. Transition zones are typically modelled using curves that "scan" from the drainage curve origin to the imbibition curve as water saturation increases. Models typically show a distinct separation between the drainage and imbibition bounding curves, within which the scanning curves are located. The shape of the scanning curve is dependent on the model used and typically retains the characteristic shape of the bounding curve.
Results from this study showed:
little spread in the bounding curves with minimal "hysteresis space" for both the kr and Pc datasets. the water imbibition bounding curve to be of lower relative permeability than the water drainage bounding curve, contrary to many models. no clear relationship of remaining oil saturation to initial water saturation.
These results may have a significant impact on how the transition zone modelling is implemented for this carbonate reservoir. This study adds to the literature data set on a topic where few full reservoir condition laboratory measurements have been published.
Well Testing of Multiple High H2S Reservoirs in an Environmentally Sensitive Area Offshore Abu Dhabi
Authors: Al Ameri F. , Al Kindi M. A. , Kuramata H. , Watanabe Y. , Tominaga N. 
Published: December 2014

Abstract
In 2013, Abu Dhabi National Oil Company and Abu Dhabi Oil Co., Ltd. (Japan), ADNOC and ADOC hereafter, drilled an appraisal well in an environmentally sensitive area located offshore Abu Dhabi, tested three zones and abandoned the well successfully in accordance with ADNOC's requirements. Since the operations were carried out in a marine protected area known to contain significant ecological resources, special measures were put in place to ensure the protection of the area during well testing operations.
In the case that the liquid hydrocarbon was oil, it was planned to recover all oil to surge tanks and subsequently re-inject the oil to the reservoir after each test. Therefore, five surge tanks were prepared and flow lines and a re-injection pump were rigged up so that the liquid in the surge tank could be re-injected to the well via a Test Xmas Tree.
In the case that the liquid hydrocarbon was condensate, it was planned to burn the condensate with burner booms, once precautions had been taken to ensure the condensate would be fully burned without any fallout. A special burner which performs fallout-free and smokeless combustion of liquid hydrocarbons produced during well testing was also prepared.
Moreover, the reservoir fluid was sour and corrosive. Well testing operations included various data acquisitions including separator sampling, bottom hole sampling, gas analysis etc. The tests were carried out using a Surface Testing Tool designed by ADOC and approved by ADNOC, which enables tests to be carried out without nippling down the BOP.
This paper will summarize the various challenges, measures taken and lessons learnt during the well test in the stringent HSE regulations and complex conditions of such challenging environments.
The Use of New Technologies to Maximize Oil Production in a Viscous Oil Field in Arctic Environment: The Nikaitchuq Experience
Authors: Raniolo S. , Mancini S. , Vimercati S. , Gentil P. , Simeone D. , Buchanan A. 
Published: December 2014

Abstract
The paper presents the experience of an accurate reservoir Development and Management for a viscous oil field and its benefits in terms of production.
The Nikaitchuq field is located in the North Slope of Alaska. The production start up was in January 2011. The main hydrocarbon reservoir is a Cretaceous sedimentary series developed in a sand lobe environment within the Schrader Bluff formation. The structure is a monocline gently dipping to NE with a gross thickness of about 30-35 ft, the reservoir is composed by two main sand bodies. The oil presents different characteristics varying between 16°-19° API with associated viscosities in the range of 50-200 cP at reservoir conditions.
The oil quality and drilling pad constraints defined a development scheme consisting of a water-flood linedrive with horizontal producers and water injection wells located side by side. Different well designs for producer wells have been implemented in time: single horizontal trajectory undulating between the two sands bodies in counterphase with the related water injectors; fishbone design with main borehole in the lower sand and multiple branches in the upper sand; multilateral counter-phase design with extended reach undulating dual laterals. As a result of the multilateral campaign, well productivity doubled with respect to the average before the intervention.
A challenging horizontal reach/depth step-out ratio between 6.0 to 6.5 has been achieved, the lateral section lengths stand between 6,000 up to 18,000 ft. The completion string was equipped to provide the capability of integrating a complex reservoir monitoring plan including distribute temperature surveys, inflow control devices and polymer tracers. Nikaitchuq is a "Digital Oil Field" and a full set of monitoring activities are performed in real time from remote.
With the aim to maximize production a set of future actions have been established: Intrawell tracers campaign for a comprehensive understanding of reservoir communication; EOR technologies to improve sweep efficiency.
At present production is sustained by 23 producers and 18 injectors. The multilateral design is now standard practice for the remaining producers. Since the multilateral campaign started up the fieldwide production step-change was evident with a doubled oil rate in a six month timeframe.
Integrated Seismic Feasibility Workflow: Elastic Modeling Approach In A Complex Near Surface Area
Authors: Mattonelli V. , Brega F. , Buia M. , Ferla M. 
Published: December 2014

Abstract
The objective of this study is to assess the most appropriate seismic acquisition parameters and processing workflow in a complex near surface area characterized by presence of extreme topography, boulder-strewn canyons and shallow fracture systems. Proper simulation of this harsh topographic and geological environment, through an elastic modeling approach, is implemented into an integrated feasibility study to identify the main effects in the seismic response.
The consequent evaluation and analysis reproduce the main issues related to processing, useful to identify reliable acquisition template and processing key-steps able to support better imaging for explorative targets in the area. The scope of elastic modeling is to simulate the effect on seismic of a system of aligned fractures, areal scatterers and canyons, located in the near surface of the future survey area. Anisotropic elastic modeling was accomplished through a finite difference (FD) code, generating the possible seismic response in terms of vertical and horizontal components (P-wave and PS-wave seismic data). The parameters and the geophysical model, input to the modeling exercise, were defined on the basis of in-place data measurements and observations (logs, outcrops, vintage seismic, etc.).
Synthetic seismic was then carefully analyzed in order to infer considerations about the geophysical problem generated by such an environment, with particular attention to surface wave generation, scattered and mode converted energy, anisotropic behavior. Denoise tests were implemented in order to identify the most effective acquisition parameters and a possible future processing strategy. The integration of the achieved results demonstrated that seismic data and the quality signal are strongly affected by the presence of canyons, in terms of diffractions and scattering; the fracture system amplifies the noise in the data, increasing the scattering effect.
An appropriate acquisition template is then proposed to reduce the noise level in the recorded data. Processing steps are also recommended to face the geophysical issues in such surface and near-surface complexities.
Digital Architecture, Infrastructure and Cultural Development in the Information Age Using 3D Animated Video Manuals for Attracting, Engaging and Enriching Future Workforce
Authors: Sanakam Sreenivasa Rao 
Published: December 2014

Abstract
This paper discusses the practical use of information management in workplace safety concentrating on current and future generation work force technical and safety training, utilizing Multimedia, Social Media, Mobile Devices and Digital Technology. Impending baby boomer retirement is creating a need for younger workers. Organizations can use multimedia tools to develop younger workforce competency and to transfer knowledge across generations immediately. Animations appeal to a technologically savvy workforce, retain subject matter expertise within organizations, transfer technical information across generations of workers, convey industry best practices effectively and can do all of the above on a global basis in multiple languages. So continuous, informal and formal ongoing flexible education techniques in compliance, processes, mandatory, crisis response training procedures will help organizations build their employee competency through animated video manuals, interactive animations and educational gaming techniques. The combination of Industry experts or (SMEs) and accomplished technical animation designers allow organizations to develop safety and technical related information that is visually engaging, precise, cost effective and superior to other alternatives. Providing a format that allows for visual learning, that helps clearly demonstrate intricate and detailed steps that is readily accessible, can be utilized anywhere employees can carry combustion proof smart phones, tablets or a computer with access to Internet or downloadable apps. Adding evaluation techniques that assess the trainee knowledge improves understanding and accuracy. Employee engagement is enhanced with mobile/digital devices. With a finger click on subjects such as field guides, risk related decision support tools, industry best practices and procedures, lessons learned and pre-job/checklists, contextualized learning, augmented learning and simulations can be provided. Animations have the ability to withstand technology changes over time without costly redesign or reconfiguration and can be used in multiple applications to assess situations, identify hazards, recognize industrially accepted procedures and implement appropriate solutions to reduce human errors on critical tasks and critical elements. In conclusion 3D animated video manuals can provide effective and inexpensive tools for training technicians on protocols and safety rules, which include best practices to convey information from experience personnel and industry experts.
From a Standard to a More Rigorous Development Framework for Unconventional Reservoirs
Authors: Colombo I. , Spelta E. , Giamminonni D. , Russo S. D. , Rotelli F. , Rotondi M. 
Published: December 2014

Abstract
During the last years, oil Majors have been struggling trying to make the unconventional business profitable. Indeed, the strategy to build an unconventional portfolio by means of merges and acquisitions is not giving enough return of investment. This is mainly due to internal processes, which contrary to Independents, are customized on a very different business model.
In addition, it is becoming clear that unconventional resources cannot be considered and developed as "statistical" ones. Nowadays, several publications are stating that only a small percentage of fractured wells is generating positive return. Even though unconventional reservoirs are considered more complex than conventional ones, less efforts are unjustifiably applied for their understanding. Hence, there is a need to switch from a "drill baby drill" to a "more from less" approach. This implies to address several issues such as: a better understanding of shale gas production mechanism at nano-scale, sweet spots identification, proper fracture placement and treatment, realistic full field simulation of fractured wells.
This paper describes how seismic-reservoir integration, advanced production analysis, accurate nano-scale and 3D full field simulations may address the above issues and help oil Companies to be more efficient in developing their unconventional portfolio. This new approach, based on placing and fraccing wells only where needed, is already providing interesting results in mature plays like the Barnett Shale and will be even more crucial for sustainable unconventional developments outside US.