bluuebunny/crossref_metadata_2025 huggingface dataset:
Assets Remote Monitoring GIS System
Authors: Tarabzouni Thamer , Al-Harbi Lafi , Al-Moaibed Ehab , Kaabi Abdulaziz
Published: June 2009

Oil and gas companies possess thousands of remotely installed assets that are critical and deemed necessary to ensure the safety and integrity of their vast operations. This fact necessitates extensive periodic field inspection trips to check asset status and operating condition. Consequently, maintenance trips are planned and executed to fix or calibrate those assets on a regular basis. Clearly this process involves many challenges, including the lack of knowledge of the assets' true operating condition and their operational effect until the next scheduled inspection visit. Also, it is difficult to determining asset locations in the field, when and why they stopped functioning, and the potential risk as a result of these failures.

Integrating a Geographic Information System (GIS) with remote asset monitoring technologies provides an innovative solution to address many of these concerns. This application will display the real-time status of these scattered assets to ensure maintaining the safety and integrity of the companies operations. The system provides visual, SMS, and e-mail alerts to report immediately any abnormal situations. The GIS provides the user with a representation of how these assets are installed geographically to unify and facilitate location and navigation tasks based on Location Based Systems (LBS) devices. GIS also allows a "Spatial" analysis to group together maintenance and inspection activities, based on priorities and geographical boundaries. This result will lead to resource optimizations (both in NDE and manpower), improve efficiency and integrity of assets, and enhance the safety of both field crews and the overall operation.
3D OBC Seismic Survey Parameters Optimization for a Carbonate Field Offshore Abu Dhabi, United Arab Emirates
Authors: Ishiyama Tomohide , Painter Derrick , Belaid Kamel , Ikawa Hidemasa , Al-Suwaidi Ahmad S. , Karwatowski Joe , Barwick David , Kaneko Mitsuyoshi
Published: June 2009

There is no doubt that 3D seismic data make a powerful contribution to field development. Less obvious, and often controversial, is the critical step of defining level of seismic survey effort required to achieve the objectives for field development. An over-specified seismic survey could be costly, and an under-specified seismic survey would not achieve the objectives.

A 3D OBC pilot seismic survey was conducted in a carbonate field of offshore Abu Dhabi, United Arab Emirates with the main objectives: (1) to demonstrate imaging of the Upper Jurassic Arab formation; and (2) to optimize survey parameters for future seismic surveys. In this highly-specified pilot seismic survey, two orthogonal 3D datasets were acquired, and one swath 3D dataset was simulated by sampling shot-points parallel to receiver-lines. The data density is significantly different among these datasets, however the offset and azimuth distributions are similar. Twenty-three cubes were generated from these datasets by decimating the full data. Unless particular reasons necessitated change, the same processing parameters were applied to all cubes to minimize any differences due to processing effects. The relationship between data quality and operational effort was determined by analyzing twenty-three cubes qualitatively and quantitatively from the structure interpretability point of view.

The main findings are: (1) higher specification cubes successfully imaged the main Upper Jurassic Arab reflectors; (2) higher specification cubes require higher operational effort; (3) in general, higher specifications improve data quality; (4) however, data quality eventually reaches a plateau even with increasing specifications; and (5) certain cubes are more efficient, they provide higher data quality with lower operational effort.

The methodology and results will be used to assist in establishing and optimizing survey parameters for future seismic surveys offshore Abu Dhabi, United Arab Emirates.
The Application of High Integrity Protection Systems to Prevent Topside Overpressure which Caused by Water Injection
Authors: Wang Jinfeng , Lili Wang , Yonghao Li , Yueping Zhuo
Published: June 2009

The Tang South-East platform is unmanned and a combined wellhead and process platform in the North Sea, it was installed to produce and separate the well streams into a vapour phase and a liquid phase, and transfer the gas and liquid in two separate pipelines to another field. There was no automatic relief system or flare system on the Tang South-East platform, and the High Integrity Protection Systems (HIPPS) was built to protect the export gas and liquid pipelines.

When water injection is applied later in Tang South-East field, it will lead to possible overpressure for the topside process systems under the situation of direct water hit through fracture.

Our solutions to prevent this overpressure can be divided into two parts:

First, design new HIPPS. Three transmitters and one Emergency Shut Down Valve (ESDV) are proposed to build downstream of each manifold, working with the other items, including Emergency Shut Down (ESD) and Independent Emergency Shut Down (IESD) panels, Master Control Valves (MCV) and Wing Control Valves (WCV). A reliability study is carried out; the resulting unavailability of the HIPPS is 9.716 × 10-5, which meets the requirement of better performance than a standard relief valve which has an unavailability of 2.12×10-4.

Second, change the process system upstream of ESDV according to new design pressure. This paper shows how to define this new design pressure which is higher than original design pressure.

HIPPS are chosen in this project basically because they offer lower install cost of flowlines and process systems, and they do not discharge to the environment.
HSE Management in a Drilling Environment
Authors: May Andrew , Moonen Alain , Logan Stewart , Allinson Jackie
Published: June 2009

Since the commencement of the Pearl GTL drilling activities in Qatar's North Field in 2004, five drilling rigs have been taken on contract and, to date, it has been a 4-year, 3 million man-hours LTI free operation.

Recognizing the challenges of an overheated industry, introducing large numbers of inexperienced staff on the drilling rigs, proactive HSE management by engaging ALL levels of the operator and contractors' organizations has resulted in top quartile HSE and operational performance.

The HSE management starts at the inception of the project and is part of the tendering process. From the moment the contracts are awarded HSE engagement sessions are utilized to align expectations and generate a road map of deliverables as per the Upstream (Well Engineering) HSE Management System (HSE MS).

The success of a "One Team" approach to HSE management is through leadership commitment, i.e. displayed by fully supporting the assignment of resources. In the preparation phase this is reflected in ‘hazardous exposure reducing’ investments, Off-site HSE induction sessions with all crews and management, ‘STOP for safety’ sessions and continuous HSE support in creating HSE cases (Rig Specific/SIMOPS).

Providing joint support in the execution phase for implementing and further optimizing HSE tools with the crews who are actually executing the job, has led to a deeper understanding and buy-in. Examples of tools utilized are Hazard Identification Bow Tie Development, Toolbox Risk Identification Cards (TRIC) as a supplement to the widely used Job safety Analysis (JSA) and STOP reporting with participation rewarding.
Challenges of Optimizing Oil Recovery of "Tight Carbonate" Reservoir, Onshore Abu Dhabi Oil Field, United Arab Emirates
Authors: Benlacheheb Mohamed , Edris Adib , Al Jeelani Omar Sultan , Al Marzouqi Salman Hassan , Al Sheehi Maryam , Al Hashemi T.A.
Published: June 2009

Production rates from tight reservoirs are marginal. However, the tight carbonate reservoir under study accounts for a significant percentage of STOIP, which is the key for drilling and producing these reservoirs. The challenges here are to optimize both the production rates and the total amount of the recovered oil. Good understanding and high quality reservoir characterization lead to efficient reservoir management plans.

The studied reservoir is over 50 ft thick and covers an area of 140 km2 with porosity ranges from 3 to 25 pu. This reservoir was deposited during a transgressive cycle on a broad and relatively shallow shelf in an open to slightly restricted subtidal marine environment. The depositional environment plays the major role as well as the diagenitic overprint in term of low reservoir quality. The reservoir is subdivided into four sub zones separated by stylolites. The reservoir can be divided into two main facies fining upward. Although the lower facies composed of Algal Skeletal Floatstone-Boundstone while the upper one is Foraminifera Wackestone, the reservoir quality is relatively low in both (permeability does not exceed 6 mD) due to the severe impact of digenesis. Although a production test conducted over this reservoir reached only 300bopd dry oil, it is still encouraging to implement a sound development plan in order to sustain a reasonable plateau and obtain an optimum recovery. Moreover, the reservoir structure is quite complex in term of isolation with the overburden dense formation and juxtaposition with lower reservoirs. Several options are considered to develop this tight reservoir, but basically they consider the use of long horizontals under WAG and Gas injection processes.

Introduction

As the industry seeks to increasingly exploit reserves of oil contained in low permeability reservoirs, the reservoir under study present an average permeability of 1 mD. Many questions have been raised about how to optimize production rate, the total amount of the recovered oil and the optimum practice to drill and complete this kind of reservoir. The effective stimulation technique to obtain economic production rate is another issue. The reservoir damages during the drilling operations and workover also represent a concern.

Geological background

The structure of the reservoir is characterized by a highly faulted elongated NE-SW anticline with a main axis length around 25km and a width of approximately 6km covering an area of 140km2. fig.1

The structure was formed during the Upper Cretaceous in response to the compressional event related to the main ophiolites obduction. Subsequent movement of the structure during the Tertiary has occurred due to the Zagros orogene event which has regionally tilted the area down the NNE.
Cyclic Water Injection Improves Oil Production in Carbonate Reservoir
Authors: Surguchev Leonid , Giske Nils Harald , Kollbotn Lars , Shchipanov Anton
Published: June 2009

The cyclic injection process to improve water flooding in carbonate reservoir was evaluated in laboratory experiments, as well as analytical and numerical simulations.

Laboratory cyclic injection experiments were performed on a carbonate rock sample with an artificial horizontal fissure. Live oil was established by in-situ recombination of dead oil with hydrocarbon gas at reservoir temperature and bubble point pressure. The experiments were designed by numerical simulation of the cyclic process. Analytical modelling was done to evaluate cyclic injection sensitivity to critical reservoir and process parameters.

The cyclic water injection experiments above oil bubble point pressure increased oil recovery by additional 2.9% of Oil Originally In Place (OOIP) above ordinary water flood. This effect can be attributed to the hasten imbibition of water into the matrix during pressurisation half-cycles and capillary retained water in the fine pores in the matrix resulting in oil counter current flow from matrix to the fracture during de-pressurisation half-cycles. Cyclic injection below bubble point pressure, designed to ensure gas saturation not exceeding the critical level, yielded additional recovery of 5.9% of OOIP. This effect may be credited to the energy of released gas, expelling the matrix oil into the fracture.

The experimental results indicate significant potential of cyclic injection to improve micro level displacement efficiency of waterflood in carbonate reservoirs.

If cyclic water injection is applied at field scale, sweep efficiency improvement from flow pattern redistribution could make an additional contribution. This has been reported by several field cases in the US, China and Former Soviet Union (FSU).
An IOC's Experience in Implementing Digital Oilfield Technologies
Authors: Hacker James M.
Published: June 2009

Efficient recovery of hydrocarbons in increasingly challenging environments requires new solutions to managing upstream assets that integrate expertise, processes and technology. This paper will describe how ExxonMobil is incorporating digital technologies into its upstream projects and operations to improve reliability and uptime, improve safety and integrity of operations, enhance environmental performance, and ultimately to increase field recovery. The primary focus is on examples that illustrate the benefits of leveraging a Global Functional Organization and worldwide standard asset management processes to integrate expertise, work processes and digital technologies to maximize asset performance. The paper concludes by presenting five critical success factors in implementing digital oilfield technologies.
Rock-Typing of Upper Jurassic (Arab) Carbonates, Offshore Abu Dhabi
Authors: Lehmann Christoph T. , Hosany Khalil I. Al , Cobb David O. , Al-Hendi Ahmed
Published: June 2009

A preliminary rock typing scheme for the Upper Jurassic was established on Arab reservoirs on a field offshore Abu Dhabi. This study was performed in order to assist in the reservoir modeling and ultimately in the accelerated development scheme of the field. The study is based on 165 samples from all the Arab reservoir levels (Arab A, B, C, D) in 6 wells. These samples were selected to cover all the reservoir facies and the range of porosity and permeability. All these samples have MICP data, thin section and porosity/permeability data. The objective was to identify the major rock types occurring in the Arab reservoirs from these samples.

Rock types of the Arab Formation can be divided into 3 major rock type groups: Limestone, Dolomite, and Anhydrite. Limestones predominantly occur in the Arab D reservoirs, the dolomites in the Arab A, B, and C. Anhydrite occurs as non-reservoir, intraformational seal, and/or baffle between Arab, A, B, and C or is intercalated in these reservoirs.

Six rock types were identified in the limestone reservoirs (L1 to L6) and five rock types were identified in the dolomite reservoirs (D1–D5). Various degree of overlap in reservoir properties do exist between some of these sub-groups. The dolomite rock types are easier to be classified into rock types compared to the limestone because of their uni-modal pore throat size distribution and well-defined capillary pressure curves. Reservoir quality is related to crystal shape, size, crystal-to-crystal contact, and dissolution.

Limestones are much more complex and reservoir quality is controlled by mud content, grain size, sorting and diagenesis. Dissolution creating vuggy porosity can create high perm zones if the vugs are connected in both dolomites and limestones. Three limestone rock types show a pronounced dual-porosity system which is difficult to characterize with conventional rock typing methods.

This work is being used to assist in the detailed characterization of the offshore field and in the ongoing field development.
Innovative Approach to Incidents Investigation Improves Contractors HSE Performance
Authors: Ataya Zaher M.
Published: June 2009

The present paper focuses on an innovative approach to HSE incident management system, (reporting, investigation and close out process), which improved drilling contractors and service companies' HSE performance and assisted in the significant reduction of the total recordable incidents rate (TRIR) and lost time injury frequency (LTIF). The paper is a combination of best practices and practical experience with incidents investigation.
A Novel Combustion Turbine Inlet Air Cooling System
Authors: Zamzam Montaser M. , Al-Amiri Abdalla M.
Published: June 2009

Combustion turbine performance is known to significantly deteriorate at elevated ambient temperatures in the Gulf Countries. This phenomenon is typically tackled by incorporating turbine inlet air-cooling systems that are generally classified under evaporative and refrigerative types. Evaporative systems have limited improvement on the turbine performance and add risk of water carryover into the compressor. However, they are simple, require minor modifications to the inlet house, and have low capital and operating costs. On the contrary, refrigerative systems are complex and require high capital and operating costs and also consume significant parasitic power for the water chillers. Nevertheless refrigerative systems guarantee the required inlet air temperature irrespective of the ambient conditions thus, achieve higher power augmentation.

This paper introduces a novel system that combines the advantages of both the above technologies. The system basically consists of chiller, cooling tower, inlet air coil, interconnecting piping and controls. The tower works as a primary source of cooling to its maximum capability after which the chiller intervenes to supplement it as a secondary source in order to achieve the desired inlet air temperature that tower solely can not achieve it. The system components are arranged in a manner such that the chiller system alternates between two distinct operational configurations to suit the incurring ambient condition; one is similar to a classical chilled water system while the other is a new arrangement in which cooling is attained by the tower solely or assisted by the chiller.

The system guarantees significant increase in power output, reduction of heat rate and exhaust temperature of turbine under various ambient conditions. The system requires smaller chiller that operates less hours and consumes much lower energy than the conventional refrigerative systems. The system also reduces the risks associated with evaporating water into the compressor intake.
High-Resolution Sequence-Stratigraphic Correlation and Facies Characterization of Upper Thamama (Lower Cretaceous) Reservoir Units and Non-Reservoir Zones, Abu Dhabi, United Arab Emirates
Authors: Al-Mansoori Abdulla , Strohmenger Christian J. , Ghani Ahmed A. , Mitchell John C.
Published: June 2009

Platform carbonates of the Lower Cretaceous Kharaib and Lower Shuaiba formations of Abu Dhabi contain three reservoir zones (Lower Kharaib, Upper Kharaib, and Lower Shuaiba Reservoir Units) bounded and separated by low porosity and very low permeability, so-called dense zones (Lower, Middle, and Upper Dense Zones).

Thirteen reservoir lithofacies and eight non-reservoir (dense) lithofacies were identified from core. Depositional environments of the three reservoir units range from lower ramp to shoal crest to near-back-shoal. The dense zones were deposited in a restricted shallow-lagoonal setting.

The Kharaib and Lower Shuaiba formations are part of the late transgressive sequence set of a second-order supersequence, built by three third-order composite sequences. The three third-order composite sequences are built by twenty fourth-order parasequence sets that show predominantly aggradational and progradational stacking patterns. The parasequence sets are bounded by sequence boundaries, maximum flooding surfaces, and flooding surfaces, which define reservoir sub-units or geological model units. These units are correlatable throughout Abu Dhabi.

Within the Kharaib Formation, third-order transgressive systems tracts are formed by mud-dominated, moderate to high porosity but low to moderate permeability carbonates, whereas grain-dominated, high to very high porosity and permeability carbonates occur in third-order highstand systems tracts. The Lower Shuaiba Formation shows a deepening-upward trend during the third-order transgressive systems tract. The overlaying third-order highstand systems tract is dominated by deeper marine mudstone to wackestone facies that shows a subtle shallowing-upward trend, as well as an upward increase in grain-richness to skeletal, peloid wackestone to packstone.

Thickness and facies changes are minor within one field and only become obvious on a sub-regional and regional view. The established sequence stratigraphic framework and sequence stratigraphy-keyed environment of deposition maps allow a better prediction of the distribution of reservoir rocks throughout the ADCO concession area.
3D OBC Seismic Data Processing for Two Overlapping Carbonate Fields Offshore Abu Dhabi, United Arab Emirates
Authors: Ishiyama Tomohide , Painter Derrick , Belaid Kamel , Gazet Stephan , Al-Suwaidi Ahmad S. , Karwatowski Joe , Mahgoub Mohamed , Furuya Keiichi , El Dakhakhny Alaa , Sinno Rick
Published: June 2009

A large 3D OBC seismic survey was conducted offshore Abu Dhabi, United Arab Emirates. This survey covered an undeveloped Lower Cretaceous Thamama field and a producing Middle Cretaceous Mishrif field and was highly-specified to achieve the different development objectives of the individual fields.

Data processing was particularly challenging. In addition to the mud-roll and trapped mode noises, inter-bed multiples and acquisition footprint that is associated with OBC data acquired offshore Abu Dhabi, there was a significant difference in raw field data quality between the two fields despite uniform processing that was applied in an attempt to obtain a seamless image across the area. A single set of parameters was applied after extensive testing in both fields using well synthetics and VSP's as to guide parameter selection at key steps in the processing flow. A conservative methodology was adopted for noise attenuation. The objective was to peal noises from the data without touching signal. Multiple targeted noise attenuation processes focused on specific noise types, were applied as opposed to a few harsh filters that addressed multiple noise types in the same step that could produce a uniform but low-resolution data set across both areas. Much of the coherent noise attenuation was performed on the separate P and Z components prior to PZ summation.

The processed final data revealed clear features: (1) continuous reflections and discontinuous fault trends; (2) channel-like-features in overburden; and (3) reefal reservoir edge; which were not mapped in previous 2D seismic surveys. However, some objectives were not fully resolved and have to be addressed in any future re-processing: (1) difference in data quality between the two fields such as S/N ratio, signal frequency bandwidth and wavelet; (2) remnant acquisition footprint; and (3) limited resolution and offset range. The marked contrast in data quality between the two fields was interpreted as being related to variations in near surface geologies. A separate targeted processing in each individual field could address these problems. The lesson learnt during the processing will help any future processing in a carbonate field of offshore Abu Dhabi, United Arab Emirates.
Analysis of Low Frequency Passive Seismic Data from an Experiment over a Carbonate Reservoir in Abu Dhabi
Authors: Berteussen K. A. , Ali M. Y. , Small J. , Anjana B. T. , Barkat B.
Published: June 2009

Passive seismic experiments using a small array of 3-component instruments were conducted over an onshore carbonate oilfield in Abu Dhabi. The aim is to confirm and understand the origins of a low frequency signals (2.5–2.8 Hz) that has been observed above several hydrocarbon reservoirs in the area and considered as a hydrocarbon indicator.

The results of the experiments indicate that a narrow-band of low frequency signal is present above the hydrocarbon reservoir as previously claimed, but that this signal is also observed over nearby assumed non-reservoir locations. Variations in the character of the signals recorded 12 hours apart during midday and midnight periods were observed.

The possible causes of this low frequency energy are not well understood. However, using the array of 3-components instruments, we are able to determine the apparent velocities and the azimuth of the wave fronts as well as the particle motion of the recorded low frequency waves. The results indicate that the observed signals are most likely due to some type of surface waves with the azimuth to the source pointing towards the nearest coastline in the area (the Arabian Gulf).
Gas Condensate Pseudopressure in Layered Reservoirs
Authors: Singh Kameshwar , Whitson Curtis H.
Published: June 2009

The paper presents verification of the Fevang-Whitson gas condensate pseudopressure method for layered reservoirs. Layers may be characterized by widely varying permeability and composition, and they may be communicating or non-communicating. The pseudopressure method is used in well calculations for coarse-grid models with relatively large areal grid dimensions (>50 m), capturing near-well condensate blockage without local grid refinement, thereby reducing runtime and model size.

The paper presents examples from several field studies, and two synthetic systems using a commercial reservoir simulator. The field studies include rich and lean condensates reservoirs.

The study was conducted using a commercial compositional reservoir simulator. 3D multi-layer, fine-grid (radial and cartesian) models and equivalent coarse grid models were used. Both depletion and gas injection cases were simulated for a wide range of reservoir fluids. Reservoir performance was compared between fine-grid models and coarse-grid models using the gas condensate pseudopressure method, showing comparable results in all cases studied, including relative permeabilities with capillary number dependence and high-velocity (P) flow treatment.

The coarse-grid model with pseudopressure is somewhat dependent on coarse-grid size, generally requiring Δx=Δy ≈ 50–100 m for lean gas condensates, and Δx=Δy ≈ 100–200 m for rich gas condensates.

The paper verifies for the first time that the gas condensate pseudopressure method as proposed by Fevang and Whitson is valid and accurate for layered systems with significant heterogeneity (permeability variation), with and without crossflow, with and without capillary number modification of relative permeabilities, and for widely-ranging fluid compositions in each layer.
Surface Deformation Around the Musandam Peninsula Detected by Differential SAR Interferometry
Authors: Onuma Takumi , Berteussen Karl , Fujita Nozomi
Published: June 2009

Repeated moderate earthquakes around the Musandam Peninsula have increased the concerns about earthquake hazards in UAE. In order to understand the influence of earthquakes around the Peninsula, long-term monitoring of the surface deformation should be considered. Pattern of surface deformation has been investigated around the Peninsula where parauthochthonous shelf carbonates ranging from Permian to Mid Cretaceous and Semail Ophiolite are widely exposed, using satellite-borne Synthetic Aperture Radar (SAR) data.

Differential Interferometry SAR (DInSAR), a promising remote sensing technique on the detection of ground displacement at an order of millimeters, was applied using nine ENVISAT ASAR scenes acquired since 2003 through 2008. Five earthquake events around Fujairah are listed in USGS/NEIC database, and co-seismic interferometry pairs that meet the baseline requirement less than 200m which is appropriate for ENVISAT ASAR interferometry processing, have been selected. Differential interferograms were stacked to detect the deformation rate with minimizing the atmospheric artifacts and phase noise. Tentative result of stacking shows that subsidence rate up to −10 mm/year in SAR line of sight direction was detected around Ras Al Khaimah Airport and Tayyibah, which may not be related with earthquakes. Also, upheaval patterns up to +7 mm/year for northern part of the Dibba Zone as well as subsidence pattern of −5 mm/year for the Khor Fakkan block are inferred which may be related with seismic activities. The result, however, is a little noisy due to limited number of interferograms, the inclusion of more scenes into the dataset, of which acquisitions have been planned, may improve the quality of the analyses. Deformation history since 2003 to 2008 using advanced analysis methods of DInSAR is another interest of the study.
Prudent and Integrated Production Planning to Maintain Excellent Operations in Angsi Field, Peninsular Malaysia Operations
Authors: Hadi Sriyanta , Osman Azmee , Bahrun Alfie Iskandar , Khalid Mas Thura , Ismaon Marliana , Rahim Parveen A
Published: June 2009

Angsi Field is an offshore field located in offshore Peninsular Malaysia, developed with an integrated oil and gas processing plant, water injection facilities and gas lift infrastructure. The field was brought to oil production at an initial rate about 30 Mstb/d in end 2001. In early 2002, it started gas production at an initial rate of about 300 MMscf/d of gas which is currently maintained at about 300-400 MMscf/d. Crude oil production peaked in 2005 and was followed by a moderate decline over the next three years. Besides crude oil and gas production, the field also produces condensate while producing gas. It was recognized that a proactive field management strategy was required in order to minimize any further production decline and maintain excellent production operations as the field production forecast showed a declining trend. Four key levers for sustaining Angsi's production were identified, namely: 1) prudent reservoir management and reliable water injection; 2) continuous production improvement and unfailing well integrity; 3) facility optimization and operational improvement; and 4) maintenance of high equipment uptime and infrastructure integrity. On top of those four levers, prudent and integrated production planning was very important in managing the integration of sub-surface and surface aspects. Various sub-surface and surface technologies were sourced with a target of sustaining production and maximizing oil and gas recovery. The lookback analysis presented here describes the use of an integrated approach in production planning and creativity in resolving problems involving reservoir management & well integrity and production operations through teamwork building.
Design and Fabrication of a Low Rate Metering Skid to Measure Internal Leak Rates of Pressurized Annuli for Determining Well Integrity Status
Authors: Al-Tamimi Ali , Al-Mansoori Shaheen , Samad Saleh , Al-Shagga M. , Hussain Ashiq , Ghneim George J.
Published: June 2009

In the oil industry, the wells are designed to have at least two tested barriers intact and maintained at all times to avoid any uncontrollable release of hydrocarbon/water at the surface. A sustained annulus pressure indicates failure of one or more well barriers. It is important to measure the leak rate associated with a barrier failure in order to properly risk assess the well from safety and operation integrity point of view.

In case of a downhole barrier (completion, tubing, casing or cement) failure, surface pressure may be seen in the annuli. In such a case, the question of how to live with and how to manage these annuli pressures are always raised. The risk associated with this failure are defined considering annulus pressure value (Should not reach Maximum Allowable Annulus Surface Pressure (MAASP) which safeguard the weakest element in the pressure envelop) and leak rate of effluent fluids of the annulus. Annulus fluid leak rate provides a sense of the leak path geometry and the risk associated with the annulus pressure in case of loss of wellhead control. The company has defined Allowable Leak Rate for oil, gas and water as 6.3 gallon/hr, 15 SCF/min and 400 gallon/hr respectively as standards. In case of sustained annulus pressure with leak rate outside the acceptable range, an immediate action is required to secure the well, carry further investigations and plan proper well intervention to restore the annulus integrity. The leak rate measurement can be performed through test vessels but this will be good for the high flow rates. The test vessel costs more money and delays other routine operations. On the basis of these limitations, the idea came to design and fabricate a portable Meter Skid capable of measuring low flow rates especially for off shore operations.

A portable fit for purpose Meter Skid to measure annulus fluids rate measurement has been fabricated by the company. The Skid is basically a small knock out drum comprises a drum with level glass, flow meter for gas and piping with gauges built on a skid with lifting hooks. During flow rate measurements, extra oil is decanted using a small portable pump. The Meter Skid is unique and one of its kind which helps to measure the small flow rates from the annuli to better define the well integrity status of the well in the light of company Well Integrity Standards.
Professional Development Advisors: The Link between Line Organizations, Management and the Training Organization
Authors: Aggour Tamir
Published: June 2009

One of the traditional problems associated with technical training is the disconnect between the training organization in charge of arranging and offering the training, and the line organizations whose engineers are receiving the training. This often results in somewhat random and unfocused training that is not always aligned with the current and future business needs of the company. Saudi Aramco has introduced the concept of the Professional Development Advisor (PDA), who serves as the intermediary between the line organization, management and the training organization. This paper discusses the roles and responsibilities of the PDA, as well as the organizational and administrative structure established to facilitate effective execution of the numerous PDA duties.

Professional Development Advisors represent the line organizations within the training organization. They are technical experts responsible for managing the curriculum for their respective disciplines. PDAs provide technical oversight of their curriculum, ensuring that it remains current and responsive to the needs of the company. Interacting extensively with their line organization as well as the other departments in the training organization, they ensure effective integration of the various training and development components, including formal training, work assignments and e-learning. The ultimate goal of PDAs is to ensure that the structure and content of technical development programs effectively and efficiently produce competent engineers and geoscientists who can contribute to their technical organizations.
3-D Seismic Evidence of Tertiary - Cretaceous Karsts & Collapse Disturbances from Offshore Oil Field in Abu Dhabi and Outcrop Analogs from Jebel Hafit, United Arab Emirates
Authors: El Awawdeh Raed , Khouri Naeema , Al Neyadi Abdulla , Shevchek Zygmunt J , Shebl Hesham , Edwards Henry Ewart , Gombos Andrew , Johns Mary
Published: June 2009

Tertiary to Cretaceous age karsts and collapse disturbances were observed from recent 3D seismic interpretation of an offshore Abu Dhabi oil-field. The seismic evidence of karst features was investigated using full-stack, spectral whitened, and discontinuity volumes. In addition, circular features were detected at specific sequence boundaries after examining curvature maps, disturbed amplitudes, velocity effects, and attenuation attributes. Several karsts and collapse disturbances tend to be associated with anhydrite beds overlaying thick carbonate intervals and seem to be limited to the Tertiary stratigraphic column; other karsts were observed to be limited to Cretaceous dolomite and limestone reservoir intervals. The Tertiary age karsts were observed to cause seismic image and amplitude disturbance at various depths, whereas the Cretaceous age karsts tend to be limited in radius and depth and have more limited effect on seismic response.

In the attempt to better understand the limit of some karsts and collapse disturbances, well data (wireline log, conventional core, and thin-section) were investigated within the karst areas and integrated with 3D seismic data. 3D seismic based geometries and attributes were analyzed to evaluate the possibility of detecting the damage-zone limit versus velocity effect with depth due to fill material. Another effect investigated is that of fracture-fault zone distribution relative to karst localization.

Analogue karst features of a similar age-range (Tertiary and younger) to the seismic examples occur within Jebel Hafit in the onshore UAE, where solution effects, debris fill, mineralization, and collapse effects can be observed and compared with the offshore examples. Here, structural discontinuities also enhance the karstic features.
Wireline "creep"
Authors: Fitzgerald Peter
Published: June 2009

Stationary operations, such as formation testing, sidewall core sampling or perforating, conducted with wireline tools are usually intended to be made at depths precisely specified with respect to some reference log. The process of correlating to the reference log is, in principle, simple, and well understood. However, regardless of how well the depth has been adjusted to match that of the reference log while the winch and downhole tool is moving towards the required station depth, when the winch is stopped the toolstring will, in general, continue to move for some time afterwards. Thus, the very act of stopping the winch leads to the development of a discrepancy between the indicated and true tool depths (with respect to the reference log). This effect, known as creep, has been recognized for many years, but recent work, described here, sheds some new light on the phenomenon.

Depth uncertainty due to creep may lead to "dry tests" when making pressure measurements, or mis-interpretation of any samples that are taken – or even a failure to take fluid samples at all, particularly in highly-laminated reservoirs. Additionally, pressure gradient determination is complicated by any uncertainty in the depths of indivivual pressure measurements. Finally, if the effect is significant during perforation operations, the well's performance may be adversely affected.

This paper discusses some of the causes of wireline creep, which are more complex than might be thought. It presents a method for estimating or measuring the amount of creep that has occurred when the toolstring finally comes to rest. It also discusses the qualitative differences between creep during typical open-hole and cased-hole wireline jobs, and some of the operational implications of these differences.

Some specific examples of creep in open hole, and a summary of a study to quantify the amount of creep observed during wireline perforating jobs, are also presented.

Some suggestions for future work to shed further light on the creep issue are made.

Finally, some recommendations for wireline operations, to minimize the impact of creep, are proposed.
Development and Application of Pressure Systems Integrity Management through Risk Based Inspection Audits in Abadan Refinery
Authors: Hashemi Seyed Javad , Javadpour Sirus , Bajestani Mohammad Nazarnezhad , Zahiri Mohammad Reza
Published: June 2009

Abadan Refinery was completed in 1912 and until 1980 this refinery was known as the largest refinery in the world. A large number of aging oil refining facilities are operating in this refinery. Older distillation plants built in the late 1950s are approaching the end of their design life. The company is facing the challenge of optimizing the return on inspection efforts in a period of time when more production is required and operating costs have to be minimized. Therefore, implementation of the latest inspection and maintenance strategies become a part of the company integrity management policy. This paper describes the methodology, analysis and results of a Risk Based Inspection (RBI) study conducted on a fifty-year-old distillation plant that was the first effort of this kind in Iran.

As a part of developing and implementing a Best Practice Integrity Management System, a multipurpose software was designed and developed by RBI team that can conduct Level 2 Fitness-For-Service assessment procedures (as defined by API RP 579) to evaluate pressurized components containing flaws or damage, and develop a comprehensive inspection program for each equipment analyzed, following the procedure and guidelines given in API 580/581 resource documents.

This paper summarizes the experiences in developing and implementing a risk based inspection strategy and the value of the RBI approach in terms of its contribution to the company's business drivers. The study has resulted in numerous benefits for the plant, which include safety and compliance issues, cost savings, and focused inspection plans using the latest NDE technology, and will assist management in making informed, defensible operational decisions.

Finally, some useful lesson learned are included to prevent common problems from recurring, to stimulate the application of better practice and where possible to prevent or reduce the failure.
Training and Development Case History: Evolution of Open-hole Logging Applications from Post-Drilling to While Drilling Requires a New Generation of Geoscientist
Authors: Hearn F. P. , Trichel K. , Thanabalasingam K.
Published: June 2009

Traditionally in the oil and gas industry, expertise in the geoscience disciplines has been built largely upon the acquisition, interpretation, and post-processing of measurements obtained from wireline-conveyed logging instruments after the well was drilled. However, the recent shift in acquisition strategies toward logging while drilling (LWD) and the evolution of while drilling applications require a new generation of geoscientist equipped with a new set of skills. An in-depth understanding of the latest LWD technology combined with knowledge of the dynamic drilling environment is essential for successful integration of while drilling applications.

A new competency management system has been implemented to facilitate the accelerated development of geoscientists in company core competencies to more effectively adapt to today's while drilling environment. The system consists of a drilling and evaluation competency framework with core disciplines, skills specific to each, and common skills that bridge these disciplines.

Mentors assigned to each geoscientist assess skills and skill gaps, provide guidance and accelerate development through direct knowledge transfer. The competency development system also includes a formal certification process and tracking system that ensures each geoscientist meets or exceeds development expectations.

There are 12 primary geoscience and drilling certifications and six advanced certifications in areas of drilling, geology, geomechanics, formation evaluation and petrophysics, reservoir engineering, reservoir navigation, integrated pressure management, wellbore integrity, and completions and production. The certification process also provides the direct link between competency development, required peripheral training (technical and non-technical), and the career ladder for geoscientists and application engineers.
Managing Downhole Parameters During Re-entry and Intervention to Improve Operational Efficiency
Authors: Joppe Lambertus , McNicol Jim
Published: June 2009

As well complexity increases, re-entry and intervention operations are becoming increasingly ambitious in both their objectives and their risk profile. At the same time, intervention and service tool operating parameters downhole are traditionally controlled by making surface adjustments based on surface readings of hook load, rpm, torque, etc. A system has been developed that measures all the physical parameters downhole at the intervention tool itself, and transmits them to surface for rig site and remote viewing, enabling real time control of intervention operations.

The new system has been used with fishing tools, sidetracking systems, and a variety of different service tools. The system captures and computes all the service tool operating parameters downhole, then uses a measurement-while-drilling (MWD) tool to send selected and critical parametric information to surface. Furthermore, bi-directional capability allows parameter formats to be updated throughout the job.

A great deal of learning has been acquired from operating the new system, mostly in the form of parameter detection, quantification, and job management; such as: detecting delicate and ultra-light events; quantifying actual torque and drag; managing helical lock-up, untoward vibration events, and exit window trajectory and quality. In conclusion, a significant number of runs have shown that surface and remote viewing of actual operating parameters in real time has enabled improvements in operational efficiency by improved decision-making that led to reduced job times. The purpose of this paper is to demonstrate this learning through multiple case histories.

A new system provides the ability to view actual downhole parameters of fishing tools, service tools, exit tools, etc. in real time, and remotely, during re-entry and intervention operations. The system is shown to have a significant impact in removing uncertainty and driving improvements in operational efficiency.
Seeking the Hidden Threat: Applications of a New Approach in Pipeline Leak Detection
Authors: Elliott Jack , Fletcher Richard , Wrigglesworth Mike
Published: June 2009

Prompt leak detection is an essential element of the integrity management process for any hazardous materials pipeline. If leaks are not detected at an early stage, they will result in progressively worse damage to the environment and can endanger the local population. Ultimately they can grow into a far more serious failure of the pipeline if not repaired in a timely manner. Therefore a variety of leak detection and/or leak prevention systems are used, including monitoring flow and pressure levels, surface monitoring and networks of sensors located along the line. However, no single system is able to detect and accurately locate all small leaks when they first occur, and many require installation and maintenance of substantial levels of costly equipment on the pipeline. For this reason, the industry is interested the in advancement of alternative approaches in leak detection. Figure 1Illustration of SmartBall™ During Operation

SmartBall is a radical new technology that has been successfully deployed in water transmission pipelines since 2004. It is now offered as a solution to the problem of leak detection in oil and gas lines too. It is a spherical acoustic device that travels through the pipeline propelled by the product flow and will detect the acoustic signature of any release of pressurized product to the environment (i.e. a leak). Its low cost, ease of deployment and the ability to immediately locate pinhole leaks to within a meter offer major benefits to pipeline integrity managers worldwide.

The paper discusses a number of case histories from the early deployment of SmartBall. The complexities of transferring the technology from a water environment to the hydrocarbons industry are addressed.
Measurement of the Volumetric Temperature Distribution in Bulk Liquid Tanks
Authors: Nguyen T. , Stojcevski A. , Veljanovski R. , Chandran J.
Published: June 2009

In this paper, we present findings from a study of the vertical and horizontal temperature distribution in a water tank to simulate a bulk petroleum tank. The temperatures were measured using discrete integrated circuit temperature sensors in a multiplexed sensor network. The experimental study found that there was a variation in the horizontal and vertical temperature profiles of up to 0.7 °C and 4.3 °C respectively. The horizontal temperature profile can be attributed to heating of the equator-facing surface from solar radiation. The temperature profile presents an uncertainty in the measurement of tank content volume and can cost tank owners many thousands of dollars.