bluuebunny/crossref_metadata_2025_split huggingface dataset:
How Technology Can Support in Tackling Drivers' Fatigue: Case of Petroleum Development Oman
Authors: Hadzic Demir , Al Esry Hamed , Marsh David 
Published: November 2020

Abstract
Petroleum Development Oman (PDO) operates in harsh environment with more than 320 million km-driven annually. Driver fatigue is one of the leading causes of Motor vehicle Incidents (MVI) within PDO operations. The objective of this research was to try and further understand how technology can support in the prevention of driver fatigue. A further objective was to explore driver beliefs related to fatigue as well as fatigue technology, which could help them in identifying fatigue in themselves and preventing further undesirable events. After the technology was applied, it was discovered that driver fatigue occurred at least once in every three journeys, whereas driver distraction occurred more than 4 times in a single journey. The initial survey showed an average level that drivers believed that the technology could prevent fatigue and further crashes. The experience conducting this research using technology greatly helped PDO HSE team to understand driver fatigue, and to develop preventative mechanisms to tackle driver fatigue.
The first chapter contains a review of the literature related to both technology and fatigue, including theory and definitions to help the reader to understand them better.
The second chapter discuss the research methodology, as well as the aim and research questions. It also includes a description of the technology, describing the system modules and their purposes.
The third chapter discusses the main data and results along with lessons learned.
Finally, the conclusion includes a discussion relating to the benefits of using technology to manage driver fatigue as well as recommendation for future enhancements.
Enhancement of Well Deliverability and Scrutinize the Proppant Discretion Based on Net Present Value
Authors: Sial Amaar , Memon Asim , Baig Abdul Ghaffar , Nawab Sohail 
Published: November 2020

Abstract
The selection of proppants is quite a challenging task as the cost almost comprises 20% to well over 50% of total fracturing jobs when ceramic is used. So, in the current situation of oil price crises, optimizing the proppant cost in Pakistan, where fracturing cost is twice as compared to the United States of America, not only provide better-optimized stimulation but also maximizes the Net Present Value. The objective of this study constitutes of two: firstly, to investigate the various types of proppants for peerless fracture parameters based on the post-frac results by using the FracCade simulator. Secondly, to evaluate the Net Present Value and select the most effective proppant based on the Net Present Value.
In this case study, the research is conducted on scrutinization of proppant discretion based on net present value, the reservoir data under the study is real-time data of x-well of Tobra formation. The average permeability of the formation is 1md. The focus of this project is to investigate the effects and potential of 25 proppants on hydraulic fracturing treatment. Prior to the selection of the proppants for the evaluation of NPV, sensitivity analysis is done based on closure stress and fracture parameters to screen out 20 proppants. The final selection of proppant is made on the Net Present Value (NPV) which will decide which proppant will give the economic edge to the fracturing treatment.
The result of the study is based on the investigation of 25 proppants based on the Net Present Value (NPV) of the fracturing treatment. Before the selection of the proppants for the evaluation of NPV. Almost 20 proppants have been screened out based on the closure stress and fracture parameters. Finally, 5 proppants after technical scrutinization are selected for the evaluation of NPV. From 17 proppants, 5 proppants are selected based on fracture conductivity. These are selected for the evaluation of NPV. Among the 25 proppants, proppant which gives the highest Net Present Value (NPV) is Sintered Bauxite which enhances the well productivity up to 3.5 times and gives the Net Present Value (NPV) of $12,548,762.98.
Enhanced Produced Water Deoiling Using a Centrifugal Separator
Authors: White Ramsey , Mulas Simone , Al-Jughayman Ahmed 
Published: November 2020

Abstract

Objectives/Scope
A field trial was conducted for deoiling produced water at a Saudi Aramco GOSP. The objective of the field trial was to prove the concept of the centrifugal separator and test its capabilities to deoil produced water at varying feed rates and inlet concentrations.

Methods, Procedures, Process
The centrifuge was fed from the common water outlet line of a gravity water oil separator. Samples were taken for oil-in-water measurement using ASTMD7678. The testing covered various flowrates and inlet concentrations, which were adjusted by manipulating upstream conditions. Several parameters were used to determine the adequacy:
Outlet oil-in water content (expected significantly less than 50 mg/l) and sufficiently high separation efficiencies to achieve the specification Unit downtime due to trip and failure of the unit and due to filter/screen cleaning and replacement

Results, Observations, Conclusions
The feed rate was adjusted by manipulating a valve at the inlet of the separator. A sample at the inlet and outlet of the separator was taken at each flowrate and condition as per the test guideline. It was noticed that inlet oil-in-water concentrations to separator were mostly on-spec, with only a few of them above 100 mg/l, as a result of temporarily lowering the dehydrator interface level for the the trial.
The following observations can be made based on the test run data:
The outlet oil-in water met the spec, far exceeding expectations Oil in water removal efficiency varied significantly, varying from 65-90% depending on rate and inlet concentration There were no issues in terms of unit downtime related to trips and filter/screen plugging

Novel/Additive Information
This was the first trial for a Saudi Aramco field. The process was applied to a facility with tight emulsions and a challenging environment that requires a highly efficient deoiling process, which the centrifugal separation has proven to be. Potential applications for produced water treatment and waste water handling can be derived from the field trial result.
Risk Mitigation Strategy Improves Drilling Performance of Shale Gas Horizontal Wells
Authors: Zhang Jinwu , Hua Jiqing , Xiong Xiaolin , Liu Jinxia , Li Mingbo , Gui Feng , Ghosh Amitava , Ong See Hong , Huang Xingning , Deng Lichuan 
Published: November 2020

Abstract
The shale revolution has extended the life cycle of the oil and gas industry, promoted the growth of global oil and gas reserves and production, and changed the energy's strategic pattern of various countries. At present, the national shale-gas demonstration area of PetroChina Changning and Weiyuan is in the stage of large-scale production. Horizontal well and hydraulic fracturing are two key technology that have proven to provide an effective way to economically develop medium to high maturity shale gas resources. However, due to geological complexity of the shale-gas demonstration area, and the lack of robust analysis and research on overpressure mechanism and wellbore instability characteristics, drilling events such as stuck pipes, lost circulations and inflows occurred frequently during horizontal well drilling. These non-productive events greatly restricts the wellbore construction cycle time and the production of shale gas reservoir. A comprehensive geomechanical study was carried out from which the three pressure profiles required for drilling, i.e., pore pressure, collapse pressure and fracture gradient, are established. The study also clarified the spatial distribution of overpressure across the field. The improved pore pressure and geomechanical understanding of the field provides the necessary inputs for an integrated, multi-disciplinary approach carried out during pre-drilled analyses, real-time monitoring and post-drilled evaluation to manage the stability of horizontal wells. The safe mud weight window derived from geomechanics provides the basis for mud weight and mud formulation designs that can be continuously optimized to improve wellbore stability and reduce drilling risks. The integrated approach has been applied for 4 horizontal wells in Weiyuan's shale gas field. One of the wells, Wei202-H34-3, has the horizontal section length of 2500m, making it the longest horizontal section recorded in the block. Drilling performance analyses of the well showed that the overall drilling risk, the wellbore construction time, and the drilling costs were substantially reduced by optimizing the drilling operations through geomechanics integrations and applications. The experience and knowledge obtained from this integrated workflow will provide guidance and serve as reference for the efficient development of unconventional oil and gas reservoirs in China.
Water Reactive Alloys with Artificial Intelligence, Smart Plugs Formulation for the Middle East and North Africa
Authors: Roy Ting , Shenoy Ram , Markel Daniel , Bolze Victor , Wilkinson Christian , Roy Indranil 
Published: November 2020

Abstract
Technology gaps to harness source rock or shale, unconventional reservoirs in the Middle East and North Africa pose unique challenges. Carbonate reservoirs, supplying Ca2+ ions resulting in passivation of traditional magnesium-based water reactive alloy alloys and abundance of H2S/CO2 rich production fluids at high pressure high temperature downhole conditions cause unpredictable degradation of plugs. This leads to the technology gap, an economical prediction mechanism to assess the degree of dissolution for deployed tools, which has prevented rapid uptake of water reactive alloys in these markets. Here we present, materials and methods to design and manufacture water reactive (fully dissolvable) alloy plugs for multi-stage stimulation (MSS) AKA hydraulic fracturing for the Middle East and North Africa (MENA). The backbone of our water reactive plug is a self-articulating amorphous and bulk nanocrystalline alloy and/or partially or fully vitrified dissolvable material with artificial intelligence (AI), sensing in its DNA, with an ability to learn from the environment it is deployed in. Additionally, these materials will deploy articles that relay information from downhole to surface without conventional telemetry. Other embodiments of the technology building blocks encompass novel, multi-layered smart water reactive nano-materials, further enhancing tailored and timed dissolution.
Application of Petroleum Geochemistry as a Surveillance Tool for Assessment of Annulus Seepage in Offshore Abu Dhabi, UAE
Authors: Koksalan Tamer , Ahsan Syed Asif , Azouq Youcef , Alhouqani Shamsa Sulaiman , Al Blooshi Ahmad , Ali Basioni Mahmoud 
Published: November 2020

Abstract
Oil leakage, due to well integrity issues of varying proportions, from downhole completions is a common phenomenon despite all measures and adherence to regulations. These leakages potentially could cause environmental damage through surface spill, aquifer contamination and in worst-case scenario loss of human lives. In an offshore setting, impact of well integrity issue can be more severe than in an onshore well due to complex and often costly offshore well operations. Downhole completions including cement quality deterioration occurs with the passage of time due primarily to corrosive nature of hydrocarbons produced from a well. Oil companies perform routine well integrity surveillance by acquiring real time annulus pressure data, cement bond, temperature and sonic logs to assess well integrity and perform remedial measures, if and when, required. Leakage may also occur in a complex pattern from nearby wells and different reservoir than the suspected reservoir and show up in the annulus or eventually on the surface. Whilst, well integrity surveillance data indicates leakage when it occurs, finding the exact source location of leakage is often difficult. Objective of this study was to perform a cost-optimized reservoir to annulus leakage oil correlation using geochemical methods in an offshore well to establish the source of oil in the annulus.
Lessons Learned from Extensive Well Testing Operations in Khuff Formations Offshore Abu Dhabi
Authors: Hollaender Florian , Basioni Mahmoud , Al Blooshi Ahmed Yahya , Elmahdi Ahmed , Sayed Sohdy , Belova Natela , Menon Pradeep , Azoug Youcef 
Published: November 2020

Abstract
Sanctioning the development of complex carbonate reservoirs and selecting an adequate development plan is not a trivial matter. Understanding formation heterogeneities such as layering, lateral continuity, natural fracture networks, or the impact of faulting are crucial to identify the optimal development strategy. Furthermore, completions strategies can have an outsized impact on the viability of such projects.
Those challenges are particularly acute in the Khuff formations offshore Abu Dhabi and detailed formation evaluation is required.
An extensive appraisal campaign was performed in Khuff reservoirs, with multiple appraisal wells drilled in different fields. Those wells were evaluated using detailed logging campaigns and then subjected to well tests, usually through drillstem testing (DST) for targeted intervals. Depending on the openhole logs, one to four tests were performed on each well.
Multiple objective had to be met: assess formation potential, tie petrophysical properties to inflow sources observed from production logs, perform descriptive pressure transient analysis to understand formation structure away from the wellbore, and assess the optimal completion and stimulation strategy.
The interpretation of well tests, combined with advanced petrophysical analysis, formation test data, and production logs, provided a unique insight into the nature of the Khuff reservoirs. A wide range of responses was observed, from tight to highly productive, but not necessarily with clear prior indications of deliverability or inflow intervals.
Clear evidence of natural fracture networks or thin highly productive zones were observed, not necessarily correlated to standard logging results. By contrast, other tests yielded more of a matrix-driven flow, even though marked by significant vertical variations. Lateral continuity was also shown to be a possible development challenge, with behavior changing significantly between wells in relative vicinity of each other.
This paper will present the observations but also offer some explanations and highlight remaining questions stemming from the analysis of the data acquired. Critically, this will show how the near-wellbore formation characteristics cannot readily yield a clear picture of larger-scale formation behavior and that only actual well testing combined with an appropriate stimulation strategy can unlock formation potential.
Observations from the appraisal data over the wide number of wells considered in this study brought a unique insight into the characteristics of the Khuff reservoirs, offshore Abu Dhabi. We highlight their complexity and identify challenges in reliably characterizing them to enable optimal development. This study also shows how well test results can uniquely provide answers not obtainable through other means.
West Africa Salt-Zone Cementing Best Practices: Laboratory Evaluation and 5-Year Field Application Review
Authors: Nana Degaul , Uba Christopher , Johnson Carl , Lonca Matthieu , Zghal Jamel 
Published: November 2020

Abstract
To determine which salt-based cement system [potassium chloride (KCl) or sodium chloride (NaCl)] was suitable for cementing across halite and anhydrite salt sections in West Africa, eight slurry recipes were tested to assess how formation salt contamination would affect slurry properties. The formation salt used for testing was sampled from a deepwater, presalt well in Angola. The recommendations developed from the laboratory study were implemented in 10 projects across West Africa over 5 years with 100% operational and well integrity success.
A candidate deepwater well was selected in which the surface and intermediate strings penetrated salt formations. A total of four slurry designs (a lead and tail slurry used on each casing string) was programmed. Each slurry was designed and tested as two distinct systems using KCl and NaCl salt respectively, yielding a total of eight slurry designs. Using the methodology and data presented by Martins et al. at the 2002 IADC/SPE Drilling Conference (SPE-74500-MS), the mass of dissolved formation salt that each slurry may receive during placement was estimated and duly incorporated into each slurry design. Subsequently, the salt-contaminated slurries were tested and compared with the properties of the initial uncontaminated slurries. Based on these results, conclusions were then made on which salt slurry system (KCl or NaCl) exhibited better liquid and set properties after contamination with formation salt. Subsequently, this knowledge was applied to 10 projects across three countries in West Africa.
This study showed that when the contact time of liquid cement slurry to salt formation was low—typically when the salt formation interval across which the cement slurry flowed was less than 100 m thick—the level of formation salt dissolution entering the slurry during placement was limited. In this case, a KCl salt-based slurry delivered improved liquid and set properties as compared with a NaCl salt-based slurry. In the field, this knowledge was applied in all oilfield projects cemented by an oilfield service company between 2015 and 2020. This included deepwater, shallow offshore, and onshore wells. All related salt-zone cement jobs, including sidetrack plugs, placed across the salt formations were successful on the first attempt.
In an absence of industry consensus around salt-formation cement slurry design, this paper validates a guideline for West Africa, based on results from laboratory testing and 5 years of field application. In contrast to current literature that recommends only NaCl salt-based slurry designs across halite or anhydrite salt intervals, this work demonstrates that KCl salt-based slurry systems can effectively be used to achieve well integrity where a halite or anhydrite salt interval is less than 100 m [328.1 ft] thick.
Modelling of Micro-Sized Graded Proppant Injection in the Natural Fractures Around a Hydraulic Fracture with Consideration of Proppant embedment and Deformation
Authors: Liu Huifeng , Li Jiaxue , Yuan Zebo , Liu Jv , Ren Dengfeng , Feng Jueyong , Lv Yongke 
Published: November 2020

AbstractNatural fractures are usually developed in unconventional reservoirs like shale, tight sandstone, CBM etc. Volume fracturing has been extensively used in such reservoirs to create a complex fracture network to provide flow paths for oil and gas. However, the stimulated area is usually very limited because conventional proppants cannot percolate into deep reservoirs. Micro-sized proppants have been introduced in recent years to increase the size of stimulation area, but the modelling of the injection of micro-sized proppants is far from good.The most representative model for micro-proppant injection is the graded proppant injection model proposed by Khanna, Keshavarz, et al. They have done a lot of work of establishing the analytical models and performing experiments to verify their models. The highlight of their work is finding the optimal proppant packing ratio. However, the biggest shortcoming of their models is that proppant deformation and the embedment of proppants into the fracture wall are neglected. Besides, how to establish an optimal injection schedule using the optimal proppant packing ratio is not clear.In this paper, an analytical model of calculating proppant deformation and embedment is introduced. It is incorporated into the graded proppant placement model to investigate the influences. Since proppant deformation and embedment will cause the reduction of natural fracture aperture, fracture conductivity instead of fracture permeability is employed to evaluate the influences of graded proppant placement. A diagram based on conductivity for determining the optimal proppant packing ratio is drawn and compared with the Khanna's diagram. Most importantly, an optimal pumping schedule for stimulating the natural fractures or cleats around a hydraulic fracture is established, and the influences of proppant deformation and embedment on it are studied.The results show that with consideration of proppant deformation and embedment, the fracture conductivity is reduced considerably and the optimal proppant packing ratio is significantly larger. The time-fixed pumping schedule and the concentration-fixed schedule are all different when proppant deformation and embedment are considered: the particle concentration is higher and the pumping interval is longer. This paper improves the previous graded micro-sized proppant injection model and the calculating results are better. The method of establishing optimal pumping schedule provides a direct guidance for researchers and onsite engineers.
Geomechanical Evidences for Conjugate Slip and Block Rotation Along the Strike
Authors: Noufal Abdelwahab 
Published: November 2020

AbstractWrench fault system is the predominant regime of Abu Dhabi tectonics and their related damage zones influences the stresses between the fault segments and hence representing the main controlling factors in field development of hydrocarbon.The strike-slip structures are related to the activation of sinistral strike-slip shear zones oriented N75°W, which initially inherited in the Arabian Plate craton and activated trough the geologic time. The main reactivation happened with the Late Jurassic- Middle Cretaceous and then by the Paleocene and finally by Late Miocene. These reactivations accompanied with block rotation of the stress tensors from NE-SW to NW-SE and finally by NE-SW respectively. The identification of transpressive and transtensional structures are the main concept of locating the hydrocarbon provinces.During the transpressive stage, sinistral transcurrent movements along the Abu Dhabi Shear Zones led to the activation of a multiple set of parallel sinistral faults, conjugate and antithetic to the master fault. The activation of these structures determined a deformation by block rotation that provoked an overall anticlockwise rotation of (N150° to N120°) of 30°.The data show how the rotations occurred might be caused by the activation of multiple strike-slip fault sets and that the rotational mechanism around vertical axes is connected to transpressive tectonics. The use of kinematic and geomechanical models allow quantification of the blocks rotation due to the combined action of multiple sets of strike-slip faults with modest displacements and to demonstrate that the rotation of blocks and their lateral movement constitute two different, contemporaneous expressions of a single deformational event. A systematic classification of the rotational zones and their influences on reservoir behavior was addressed.Classification of stressed zones favoring reactivation based on their location relative to fault segments growth. Therefore, development of structures were combined with fluid flow in/between fault segments to characterize placing wells for an effective field development plan.