bluuebunny/crossref_metadata_2025_split huggingface dataset:
Successful Flood-Front and Breakthrough Prediction of Miscible WAG in a Complex Carbonate Reservoir - A Case Study
Authors: Qureshi Z. U. , Ashqar Ayham , Banyopadhyay Indrajit , Al Hammadi Khaled 
Published: November 2016

Abstract
Water alternating gas (WAG) is employed to improve flood mobility, and sweep efficiency during gas injection by squeezing more oil out of the reservoir. Injected water sweeps the lower part of the reservoir, while gas tends to sweep the upper part due to gravitational forces. Accurate mapping of fluids and their distribution across the reservoir is an important aspect of characterizing reservoir properties. Understanding the performance of the injected fluids, and their flow pattern is critical to understand reservoir behavior, the interaction between the fluids at reservoir level, and quality check the reservoir dynamic model.
Techniques such as tracer injection and time lapse logging are utilized as a method to monitor, and confirm flood front arrival. Pulse neutron decay time log (PNL) is a common method used to monitor reservoir fluid movement behind casing. Multi detector pulse neutron decay improves the tool capabilities and enhances its potential in detecting gas flood front and its miscibility.
Interpreting reservoir monitoring logs requires combining the innovative knowledge on the tool physics and understanding reservoir properties. Integrating all available data is an important step towards the correct interpretation.
Multi detector neutron pulse decay was run in time lapse logging using same tool provider to allow consistency. The tool has successfully mapped the approach of injected gas, it clearly showed the change in fluid properties over time, and most importantly has shown the type of fluid approaching. Few months later gas tracer was found in the close-by producer.
This paper shows a case study of successful integration of the results of six years’ time lapse logging with the dynamic simulation model, in a field located onshore Abu Dhabi UAE, and subject to rich gas EOR recovery through WAG cycling system. Gas tracer and PNL were used to monitor the flood front and break through. The flood movement mapped from neutron pulse decay with time lapse, was successfully history matched in the dynamic simulation model. The calibrated simulation model is used to monitor the further advancement of flood front.
GASCO ASAB-0 Turnaround 2016; Systems Dynamics for Extra-Ordinary Results
Authors: Al Hamed Omar , Nair Girish Kumar 
Published: November 2016

Abstract
Oil and Gas world is going through difficult times, with crude prices breaching some of the all-time low values. GASCO believes that, such situations call for extra ordinary efforts to control and extract best results out of every opportunity. Shutdowns/Turnarounds are such cost centric opportunities where careful and controlled actions can have significant effects on company bottom lines. This paper intends to portray the caution, controls and practices during Execution during Asab-0 Turnaround-February 2016, which enabled in producing extra ordinary results for GASCO.
GASCO operates its Turnarounds (TA) based on a well-documented ‘Shutdown Manual’, which has strong background in Maintenance Excellence practices on a well-defined process approach.
In order to control the TA effectively, Key Result Areas (KRA) were identified and actions were put in place for lean management of the various elements involved. Principles of Systems Dynamics were used to integrate various functions, people and hierarchies to break down silos in communication. Each of the KRA’s had elements of this approach in order to achieve performance up-scaling.
The KRA’s identified were: Cost optimization - achieved through resource optimization (pooling; Seamless integration for optimal use of all available resources (human/equipment)), iterative/dynamic planning, adequate contracting strategy (Performance-based), integrative thinking approach (Minimal Compartmentalization) with stakeholders and early start up.Scope Control - managed through strict control over scope creep and exercising continuous, dynamic scope optimizations.Schedule Control – optimization by implementing Critical Chain Method instead of Critical path, thus buffering floats towards end of TA activities enabling early completion. Also, "Daily Look Ahead" and "Look Back" prevented schedule slips.Quality – ensured by implementing GASCO TA vision of "Faultless Turnarounds", achieved through micro level planning. Many tools like IPF Functional test control sheet, Start up Readiness Certificates etc. were put in place to ensure ownership of quality to avoid errors, rather than rectify them.Efficiency, Effectiveness – Maximization achieved by establishing a transparent communication environment where cross functional interactions were ensured to be seamless and through careful resource/process management.
In line with GASCO’s established objective of ‘Delivering Exceptional Results’ and Turnaround Excellence goals, ASAB-0 Turnaround delivered a saving of approximately 6 MUSD by achieving plant start-up 3 days in advance, without compromising on HSE or Quality. Combined effect of all the above practices helped GASCO ASAB team deliver these extra ordinary results.
Free Rotating Eccentric Guide Shoe Reached TD in High Angle Well Saves ±60 Hours of Rig Time
Authors: Shabbir Huzefa , Al-Marzooqi Abdulmohsen , Khamis Mostafa , Marwan Kadri 
Published: November 2016

Abstract
In the pursuit to access reserves at ever increasing departures the ability to successfully run very long casing strings in highly deviated wells is essential. Running 6200 ft. (1890 m.) long 7″ liner in a highly deviated ‘S’ shape well (80 Deg.) with high dogleg severity 15 Deg. /100 ft. across whipstock window) is considered a big challenge. The severity of this challenge increases multifold while passing the string through challenging interbedded formations.
The case presented here had unique achievement that last seven days while performing extensive open-hole logging after drilling 8-½″ section and prior running the liner hanger system. Aligned with the pre-determined challenges; the normal drilling practice is performing two wiper trips. First wiper trip after drilling the 8-½″ section, pulling out till the 9–5/8″ window at 8740 ft. and RIH again till 8-½″ TD at 14442 ft., the first wiper trip would have consumed +/- 24 hours rig time. Then follow with another wiper trip through running 8-½″ drilling BHA from surface till TD at 14442 ft. after pulling out of hole with the logging tools, the second wiper trip would have consumed +/- 36 hours. Accordingly, a total of +/- 60 hours rig time would have been consumed in both wiper trips. Wiper trips would have increase the gap between finalizing drilling 8-½″ hole and running liner hanger system. Increasing the gap would thereby increased the possibility of open-hole pack-off while running the liner hanger system. Accordingly, an optimum solution is to run Free Rotating Eccentric Guide Shoe (FREG) with two Sure Seal valves each provided a 3.14 square inch (20.3 CM2) minimum flow area to allow large cuttings and debris to pass through. In addition, any resulting side force during running would rotates the guide shoe away from the obstruction, thus allowing continued running of the pipe to the predetermined depth without rotation of the entire casing or liner string and reducing the risk of string stuck. Accordingly, the risk of pulling out of hole twice and performing two wiper trips was eliminated.
Deriving 3D Model of Reservoir Geomechanical Properties Through an Integrated Geostatistical and Basin Modeling Approach - An Example from a Mature Field in Saskatchewan, Western Canada
Authors: Saikia Kalyan , Ikuku Clara E. , Zawar Pankaj 
Published: November 2016

Abstract
Measurement of geomechanical properties using seismic and laboratory methods have been used in oil and gas industry for several years. Laboratory methods, in most cases, take only small samples from consolidated rocks, which may not be representative of the elastic regime existing in the reservoir owing to sample size. In general, geomechanical studies are performed on a well-by-well basis. Measurements calculated at the wellsite are then used as calibration points to convert the 3-D seismic data to geomechanical cube. However, elastic properties measured this way are restricted to the well location and cannot be interpolated across the reservoir. To overcome these challenges, this paper describes an approach for deriving and discretizing geomechanical and other elastic properties in the reservoir by integrating results of 3D geo-cellular and basin models.
The workflow presented in this paper is utilized to calculate cell-by-cell elastic properties of the reservoir by integrating parameters from both basin model and 3D geo-cellular grid. The basin model reconstructs the geologic history (i.e. burial history) by back-stripping the reservoir to its original depositional thickness. Through this reconstruction, the mechanical compaction, pore pressures, effective stress, and porosity-vs-depth relationships are established for the reservoirs. In the final stage, dicretized calculations of geomechanical properties are assigned to each lithotype (facies) in the geomodel. The discretization of elastic properties into 3D grids resulted in better understanding of the prevailing rock elastic properties and stress regimes helping hydraulic fracturing operators in the effective design of their depletion strategies with minimal drilling risks and costs. This approach provides an innovative way of determining effective minimum horizontal stress for the entire reservoir through distribution of elastic properties in a 3D grid. The conventional approach of using small sample plugs is not sufficient to describe elastic properties for an entire reservoir and can be replaced by current approach.
Remnant Life Study of Rotating Machinery at Zakum Field, Umm Shaif Field and Das Island
Authors: Almemari S. , Duncan A. 
Published: November 2016

Abstract
Regular life cycle of any equipment undergoes various stages starting with R&D phase, concept design, procurement, construction, initial operation, beneficial operation, mature operation, and at last, remnant life stage. Cost involvement accordingly varies per stage, which can be demonstrated with reference to fig. 1. Anticipated cost for an equipment at the remnant life stage is at highest compared to other costs during equipment life, which shall be assessed thoroughly to sustain optimum operation in line with maintaining reasonable expenditure. The scope of RLA was to assess life expectancy, performance, technical integrity, CAPEX, and emission across ADMA OPCO's existing critical list of rotating machineries. Approach taken to conduct the study and compile the results was through various interviews, site visits, data reviews / analysis, and collecting team experiences. As a result from RLA, ADMA OPCO highlighted major areas of concerns and were given a better position to develop a well-established CAPEX estimate and replacement scope for existing rotating machinery fleet.
Structured Analysis of Pump Systems Unleashing Novel Horizons of Energy Savings
Authors: Sajjad S. , Dias B. , Al Jenaibi E. 
Published: November 2016

Abstract
Pumps are large consumers of energy and play a vital role in daily operations at the Oil & Gas processing facilities. General tendency to oversize pumps during design phase in order to tackle all possible scenarios or conditions leads to inefficient pump operation thus resulting in higher energy costs. Changes in feed characteristics and throughput for a given facility due to numerous reasons also supplements higher energy costs and inefficient pump operations. Energy performance study has been conducted for selected pumps at an Oil & Gas processing facility. In this study, most of the pumps indicated higher head than actual requirements for the given flow conditions, highlighting potential of energy savings. Generally, multiple solutions are applicable for optimization of any pump operation. Potential solutions include changing running / standby configuration, installing Variable Frequency Drive (VFD), replacing pump motor, trimming impeller, replacing pump and modifying the system resistance by adding, removing or changing the components like valves and orifices etc. Each solution exhibits different magnitude of energy savings and CAPEX requirements. This paper introduces a systematic methodology for a structured analysis of pump systems, to explore and evaluate potential solutions for energy efficiency improvement. Targeting pumping system improvement thru this structured approach would help to evaluate all pertinent solutions, in conjunction with techno commercial analysis, and identify the best solution. Proposed methodology has been applied on four different cases of pump operation optimization and the results are discussed in this paper.
ADMA Integrity Assurance in Major Projects
Authors: Al Marzooqi Mahdi Mohamed , Al-Hameli Mohamed Saif , Al-Sayed Talal A , Khade Sanjay Harishchandra , Yella Srikanth 
Published: November 2016

Abstract
Through this paper, the author intends to share the valuable experience of benefits in introducing the Integrity assurance program in a structured manner at early projects stage starting from Assess, Select Define through to the commissioning stages.
ADMA is pioneer in major Oil & Gas producers worldwide where critical Integrity Deliverables are embedded through customsied locally designed Code of Practice (CoP-036 "Integrity Assurance in Projects) in Value Assurance Process (VAP) stages, enabling robust control on Integrity Measures upfront. Early identification of Integrity risks with proactive mitigations based on experience from previous Projects. This initiative prevents operating critical facilities with unknown HSE and business risks. The process is embedded within project activities implemented through PMT having full knowledge of design and complete as-built data. This essentially ensures best outcome with significant cost savings.
Early interventions result in timely risk reduction. Saving significantly in CAPEX / OPEX and enabling smooth commissioning handover. Preventing failures, unplanned shutdowns thereby providing adequate confidence to stake-holders during entire life-cycle of the facilities.
Being unique in MENA; ADMA is the first and only company in ADNOC group where there is direct involvement/integration from Integrity Division in the major full field development projects, thus decades of operational experience and lessons learnt are directly fed into the projects.
Proactive Learning from Process Safety Events to Prevent Process Safety Events in an Oilfield Services Provider
Authors: Peresypkin Sergey , Fei Leong Weng 
Published: November 2016

Abstract
Since the introduction of upstream process safety programs to manage various critical activities of an oilfield services provider, much has been learned in this pioneering field which allowed us to further fine- tune the program in preventing process safety events during well services operations. This paper examines in detail, using several past upstream process safety incident case studies within the Middle East and Asia Pacific region, and demonstrates how effectively investigated and understood UPS barrier failures contribute to improved implementation of the upstream process safety program and effectively prevent recurrence of such events. Key failure modes and root causes involved in these upstream process safety incidents and near misses will be analyzed in detail. Using barrier check tools employed as part of the upstream process safety program for the various well services activities, an analysis will be done to evaluate if the barrier check tools would have helped prevent these incidents. Some leading performance indicators will also be discussed and use of learnings from process safety events serve as a validation point for understanding effectiveness of the operationalization effort for upstream process safety. The barrier check tools will be briefly introduced early on to give context to this endeavor. Where there are inadequacies in the program, these will be identified from this review and will be fed back into review of the upstream process safety program. Highlighting the impact of the program in potentially preventing these incidents helps reinforce the appreciation for effective implementation and execution of the upstream process safety requirements. The proactive learning process from operationalization of upstream process safety goes toward improving the execution of the program as well as driving towards consistency within the industry in operationalizing upstream process safety.
Well Productivity Analysis Integrating Ultra-High Resolution LWD Images and PLT: A Data Integration Case Study
Authors: Shehhi H. M. , Shehab S. S , Celma R. I. , Girinathan S. , Sadaoui B. 
Published: November 2016

Abstract
The Production estimated from standard porosity logs in carbonate reservoirs has often been greater than expected. This study looks for the correlation between well productivity and high resolution porosity information derived from borehole electrical images. Good production contribution has been obtained from intervals where logs show low porosity (verified by PLT analysis) whereas zones having higher porosity could have major or minor contribution to the well production. Carbonates, in general, have complex porosity systems with widely varying proportions of primary and secondary porosities. The term "secondary porosity" includes vugs, moulds, bioturbation features and open fractures that are often missed on conventional porosity logs. These diagenetic phenomena are not captured on coarser resolution conventional logs (density, neutron and sonic), thus porosity is usually under-estimated or overlooked.
Resistivity images have been known to provide both high resolution and azimuthal borehole coverage to characterize reservoir heterogeneity from a qualitative perspective. New generation LWD borehole imagers record wireline-par resolution data while rotating at full borehole coverage (unlike wireline imagers). This case study sets sight on two horizontals wells – one injector and one producer – targeting Lower Cretaceous carbonates. Production / Injection logging (PLT) data are integrated with high resolution image-derived geological information to explain the nature of flow profile and dominant textural parameters at play at various levels along the borehole-section. Part of this exercise seeks to derive a more quantitative high resolution image-based secondary porosity by solving the porosity from the Archie equation in the flushed zone.
The workflow arrived at, allows one to understand correlations between various carbonate porosity components and well productivity data. In the present case study, it is concluded that not all productivity is derived from primary porosity. This is important in terms of well completion, carrying out optimized completion, design of hydraulic fracturing stages and placement of packers and inflow control devices.
Integrated Reservoir Characterization to Approach the Carbonate Permeability Distribution Challenges: Case Study from Offshore Abu Dhabi
Authors: Elarouci F. , Maalouf C. B , Espinoza I. Baca , Al-jaberi S. M. , Amer M. , Smith S. S. , Jalalh A. A. 
Published: November 2016

Abstract
Heterogeneous carbonates formations have unique challenge to obtain representative permeability values. During the exploration phase and due to the limited number of wells and technologies, the initial formation evaluation might be misleading. The permeability results from conventional core analysis (CCA) might be significantly under evaluated because vertical interference tests from a wireline formation tester and production tests show different results. This paper describes a case study in offshore Abu Dhabi and solutions that should be assessed to overcome this challenge.
An integrated approach was performed to determine the possible causes of permeability mismatch between cores, logs, wireline formation testers and production tests in this field. Based on logs and core data, the reservoir was subdivided into different layers and further refined using permeability indices from NMR logs. Formation testers with advance measurements were used to evaluate effective vertical and horizontal permeability of a single layer. The production testing covering several layers was used to fine-tune subzone permeability and subsequent flow units.
The results from this study show that permeability given by CCA was somewhat misleading due to physical limitations from core plugging. The detailed core description and well-test data indicate that a significant portion of flow passes through high-permeability (vuggy) sections of the formation that cannot be measured by plugs. A formation tester was applied to check vertical and horizontal permeability in one productive zone.
Various methods were integrated in the study to reconcile the unexpected high productivity of the sub-layer and explain permeability distribution from different tools. This case study provides a useful example in identifying and explaining data from reservoirs where the dynamic well productivity data differs from static data prediction.
Experimental and Numerical Studies on EOR Using a Biosurfactant
Authors: Saito Minoru , Sugai Yuichi , Sasaki Kyuro , Okamoto Yoshifumi , Ouyang Chencan 
Published: November 2016

Abstract
The EOR potential of a biosurfactant was evaluated through core flooding experiments and numerical simulation in this study. The biosurfactant which was called surfactin was generated by a microorganism belonging to Bacillus species. The EOR potential of surfactins has been already reported by previous papers, however, that of surfactins can be different depending on their making process such as the conditions of incubation, extraction, purification, etc. This study used a surfactin which was made by Kaneka corporation's original techniques.
Core flooding experiments were carried out under ambient temperature and pressure to evaluate the EOR potential of the surfactin. Berea sandstone cores whose permeability was 50 md were used in this study. The surfactin solution was injected into cores after water flooding. 3 experiments were carried out by injecting surfactin solution whose surfactin concentration was 0.3 %, 0.03 % and 0.003 % respectively. An experiments were carried out by injecting the culture solution which had been diluted so that the surfactin concentration was 0.3 %. 4 experiments were carried out by injecting sodium dodecyl sulfate (SDS) solution which had been supplemented with a slight amount of surfactin or the culture solution. An injection was continued until oil was not produced completely.
Higher oil recovery was obtained by injecting higher concentration of surfactin. 13.6 % of original oil in place (OOIP) was recovered by injecting 0.3 % of pure surfactin solution, whereas 6.3 % of OOIP was recovered by injecting 0.3 % of pure SDS solution. 0.27 % of SDS solution which was supplemented with surfactin whose concentration was 0.03 % could recover 14.7 % of OOIP. 23.9 % of OOIP could be recovered by injecting the culture solution which was diluted by 16 times so that the surfactin concentration was 0.3 %. Enhancement of oil recovery which was obtained by injecting SDS solution supplemented with the culture solution was a little lower than that with pure surfactin.
The EOR potential of surfactin is quite higher than that of SDS. It was shown that the surfactin can be useful as a cosurfactant for SDS. Culture solution of the microorganism demonstrated much higher EOR potential than pure surfactin, therefore, it may include effective components other than the surfactin. Utilization of the culture solution is economically advantageous.
Numerical simulation was also carried out using UTCHEM, a reservoir simulator for chemical EOR. The simulation model accurately history matched the core flooding experiments and allowed us to scale from the lab scale to the pilot scale.