bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Causal Link Between Paleoenvironmental Dynamics and Borehole Instability in a Cenomanian Carbonate Reservoir, Offshore Abu Dhabi
Authors: Yamamoto K. , Obara H. , Tsusaka K. , Tsuji Y. , Al-Farhan Z. A. , Aljneibi M. M. , Takayanagi H. , Kurita H. , Sato T. , Iryu Y. 
Published: November 2016

Abstract
In the studied oil field offshore Abu Dhabi, horizontal wells in the upper part of the Cenomanian "E" Formation composed of shallow-marine carbonates often encounter unexpected rocks characterized by high GR values. They have been referred to as "High-GR section (HGRS)" and thought to cause borehole instability. This paper aims to unravel the geological factors that caused the borehole instability.
Coaly shale observed in cores had long been believed to be the problematic HGRS. Therefore, we conducted litho-, chemo- and biostratigraphic analyses and well log evaluation on the coaly shale and the surrounding deposits.
The obtained results indicate that the coaly shale occurs as thin stratiform layers which were formed under a salt to brackish marsh environment during the deposition of the uppermost part of the "E" Formation. Although the Cenomanian/Turonian transition is the period of the Cretaceous thermal maximum when the global sea level was very high, the "E" Formation was largely exposed in the Turonian due to a regional tectonic uplift caused by the Oman ophiolite obduction onto the southeastern Arabian Plate. Coal deposition and the subsequent significant karstification in the studied field were caused by a greenhouse-induced warm and humid climate.
GR log responses of the HGRS in the horizontal wells are classified into two types. One is a spiky shift that often reaches very-high GR values (&gt;100 gAPI), and the other is a much broader shift with a flat plateau with moderately-high GR values (60–80 gAPI). The latter is always found in the wells with the borehole instability. Calibration of GR logs to the core data in the same vertical/deviated wells suggests that the intervals with very-high GR values (&gt;100 gAPI) observed in the horizontal wells correspond to the coaly shale of the "E" Formation. Whereas, the intervals with moderately-high GR values (60–80 gAPI), which are too low for the coaly shale, are equivalent to marine shale of the overlying "B" Formation.
Karstic features including chaotic cave breccia are often observed in the upper part of the "E" Formation, which suggests that caves were likely formed during the episodic subaerial exposures. Subsequently, cave collapse likely occurred during and/or after the deposition of the "B" Formation, and it could pull down the overlying "B" Formation to the reservoir level of the "E" Formation, accompanying the coaly shale.
We consider that the borehole instability was primarily induced by penetrating the structurally-depressed "B" Formation, rather than the coaly shale. This new concept is based on a comprehensive understanding of the causal link between the paleoenvironmental dynamics and the borehole instability in the studied field.
Intelligent Use of Data Management Strategies Applied to the Oil and Gas Upstream Lifecycle
Authors: Mancilla Jose J. 
Published: November 2016

Abstract
This work identifies data management pillars and structure, and discusses strategies and processes in each area to obtain data with excellent quality that is centralized in a single database. Upstream data from various data sources is therefore available through a single access point, which enables interpreters to analyze the data quality and to create projects based on certified data.
The data management pillars identified include preserving historical information, new information, data integrity, and basic metadata for key variables and attributes.
Several data management challenges existed that were addressed by the strategy developed. These challenges include preserving information over time, reducing data duplication, achieving consistency across areas and platforms, and ensuring that the data are available. In addition, the strategy must provide information security and improve business decision making capabilities.
The primary benefits of the strategy used to address the challenges include reduced costs, improved time, and increased availability of data.
An integrated solution was implemented in a recent successful case for a major oil company in which key data management pillars were identified, and a new approach was established to improve the data quality of the oil and gas upstream lifecycle information. After implementing the solution, improvements were made for new information quality control and in the availability time for the interpreters. The final users and managers were able to know the status and the key performance indicators (KPIs) of their data projects before beginning work and during the entire interpretation process. In addition, the teams were able to generate synergies to make the necessary validations to preserve geological knowledge. Finally, the technical users could quickly identify the information to be used in the different leases and areas of interest.
Axial Interaction Behavior of Offshore Pipelines
Authors: Senthilkumar M. , Kodikara J. , Rajeev P. , Robert D. J. 
Published: November 2016

Abstract
Pipe-soil interaction behavior in the axial direction is an important design parameter for offshore pipe design. Governed primarily by the axial interaction behavior, the thermal expansion of the pipe wall could cause the pipe to either freely expand, or buckle on the founded seabed. Therefore, it emphasized that by controlling the axial interaction behavior, the overall pipe on-bottom stability can be effectively managed. This paper presents laboratory experiments performed at Monash University to understand the pipe-soil interaction behavior in the axial direction. A special 2-D actuator test setup was developed to study axial walking of pipe on clay seabed under both drained and undrained loading conditions. The effect of pipe loading rate, pipe embedment, and shutdown cycles on axial friction force were explored. Based on the experimental results, the pre-peak, peak and residual components of the axial force-displacement curve were identified and explained using a simplified theoretical framework.
Impact of Individual Ions on Oil/Brine/Rock Interface: A Macroscopic Insight on Wettability Alteration
Authors: AlGeer M. A. , Gmira A. , Al-Enezi S. M , Yousef A. A. 
Published: November 2016

Abstract
SmartWater injection is a proven technology and a successful recovery method in carbonates at tertiary and secondary modes that showed significant incremental oil recovery compared to seawater injection. The objective of this paper is to bring new insights on wettability alteration mechanisms caused by SmartWater by investigating the effects of single ions (monovalent and divalent) at fixed salinity on rock/fluids and fluid/fluid interactions. Contact Angle (CA) measurements of oil, carbonate rock and different SmartWater recipes at fixed salinity were conducted at different temperatures and pressures in an attempt to evaluate the impact of individual components on the wettability of oil/brine/rock systems. Contact angle data are compiled and compared to rock surface potential properties obtained by earlier Interfacial Tension (IFT) measurements. This integration will help to identify the role and influence of individual mono and divalent ions on the wettability alteration mechanisms.
The data analysis confirms the sensitivity of contact angle against different temperatures and reveals the effect of individual key ions on crude oil/water/rock interface. At fixed salinity, different SmartWater recipes give different contact angle values, indicating that the interplay of determining ions is critical to fluid/rock interactions as individual ions play different roles depending on their valence, which will affect the wettability, and ultimately the oil recovery. SmartWater recipes that are composed of Mg2+ ions solely have exhibited a lower level of contact angle values compared to other SmartWater key ionic components. Na+ and Ca2+ have shown a comparable contact angle level, while SO42- ions, generally, have resulted in low contact angle values only at elevated temperatures. The ultimate goal of this study is to enhance our understanding of carbonate wettability alteration by integrating the role of oil/brine/rock interactions and the effect of individual mono and divalent ions. These efforts will ultimately lead to additional oil recovery through optimizing injected SmartWater recipes.
Case Study of CO2 Injection to Enhance Oil Recovery into the Transition Zone of a Tight Carbonate Reservoir
Authors: Luis Figuera , Al Hammadi Khaled , Tanakov Mikhail 
Published: November 2016

Abstract
This paper presents a case of study of carbon dioxide (CO2) injection into the Transition Zone (TZ) of a heterogeneous, low dipping and tight carbonate oil reservoir. In such reservoir, a relatively thick TZ is expected to contain 30% of the oil in place that would not be commercially feasible to target by water flood. Therefore, the development of this area by Enhanced Oil Recovery (EOR) methods offers a valuable source of oil production.
CO2 injection into oil reservoirs is well known as an efficient EOR process as well as one of the promising technologies for reducing greenhouse gas emissions. This study was conducted with the objective to enhance oil recovery in the TZ and also to utilize anthropogenic CO2 as an effective substitute for hydrocarbon (HC) gas injection.
In order to define the optimum production strategy to maximize oil recovery, compositional reservoir simulation models were developed and utilized. The effects of several flood design parameters on the efficiency of the process were evaluated, such as: the number of wells and well patterns, well designs, injection schemes, injection and production rates, etc.
This paper describes primarily the modeling and flow simulation process developed and utilized for the design of the first commercial CO2 EOR project in the Middle East region to become operational in 2016. The modeling workflow incorporates several important steps from 1-D simulation model to large scale complex compositional simulation models with geological high-resolution grids. The simulation work is supported by a comprehensive and reliable experimental data such as PVT, swelling tests, slim tube and core flood displacement experiments. Important operational experience, understanding of CO2 migration within multiple sub-zone and lessons learned from the CO2-EOR pilot previously conducted in the same field2 are used to reduce technical and commercial risks. An extensive reservoir monitoring plan has been developed to further improve the understanding of reservoir performance, calibrate the models and optimize the CO2 flood. This paper concludes with an assessment of the potential benefits of CO2 injection in the TZ that opens additional development opportunities in other fields.
Challenges and Solutions While Cementing Long Extended Reach Wells in UAE
Authors: Navas Luis , Bermudez Romulo , Saleh Medhat G. , Al Katheeri Yousif Saleh , El Hassan Azza , Kapoor Saurabh , Jain Bipin , Pallapothu Surya , Shakour Sherif Abdel , Sinha Ravi Kumar 
Published: November 2016

Abstract
In 2012 ZADCO commenced drilling operations from artificial islands in the Upper Zakum field. The field development is based on drilling extended reach wells up to 35,000 ft measured depth in three different reservoirs. More than twenty wells have been drilled from these islands so far, with the longest well reaching ~31,000 ft MD. Longer than 35,000 ft MD wells are planned to be drilled in the near future. The 9-5/8″ casing in 12-¼″ open hole is set at a measured depth of ~9,000-17,000 ft with cement designed to reach surface. There are several challenges experienced while cementing these wells, due to the narrow pore and fracture pressure gradients. Key challenges include: ECD management, maintaining fluids density and rheology hierarchy, proper centralization, lost circulation, use of NAF drilling fluids and limitations to pipe movement opportunities. Based on ultrasonic imaging of initial wells, the overall desired cement bond was not as good as desired on initial wells. Several improved practices were applied to enhance the cement bond across reservoir sections. However, the log quality was still below expectations. Hence, a more robust solution was required to successfully cement the long maximum reservoir contact (MRC) wells.
These challenges were successfully addressed and mitigated through a step-wise approach. The cement slurry designs were optimized by adjusting rheologies and static gel strength, lowering fluid loss values, adding lost circulation material and using trimodal cement designs. Mud removal was further enhanced by using better cleaners in the spacer system to provide efficient cleaning and de-emulsification. Updated mud conditioning procedures and better centralizers was also implemented.
Cement bond log and interpretation techniques were improved by using ultrasonic measurements and flexural attenuation measurements and imaging the annulus through these tools to determine actual casing centralization. The log showed a significant improvement especially across the horizontal reservoir sections.
The use of these techniques has improved cement quality and enhanced zonal isolation of the producing zones in these horizontal MRC wells and will assist in maintaining the quality for future development of the Upper Zakum field.
Achieving Excellence in Offshore logistics & Supply Chain Management, UZ750 EPC1&EPC2 Modularization and Transportation Directly to UZ Artificial Islands
Authors: Fahmy Ibrahim , Macaulay James , Bufalah Salah J. 
Published: November 2016

Abstract
Zakum Field is the back bone of the UAE economy contributing approximately 35 % of the overall UAE oil revenue.
ZADCO, on behalf of its shareholders, has a strategic target by managing UZ750 Project to increase the production to 750K BPD crude oil from the Zakum Field.
The project involved Building, Transportation and installation of approximately 270 Structures required to complete the Offshore construction of UZ750 EPC1& EPC2 Projects.
Co-Development Plan Optimization of Complex Multiple Reservoirs for Giant Offshore Middle East Oil Field
Authors: Khan Mohammad Yunus , Tiwari Anupam , Ikeda Shuichiro , Syed Fahad I. , Al Sowaidi Alunood K. , Martin John 
Published: November 2016

Abstract
An extensive study was conducted to revise the field development plan (FDP) of a giant offshore Middle East oil field. The subject field contains several stacked reservoirs with light oil and has a long production life extending beyond 100 years. Primary recovery began in 1968. The field has been under water flooding with pattern injection since 1982.
In the subject reservoir, most of injector wells are located in a concentric ring along the crest. This reservoir is currently undergoing further redevelopment with a line drive injection pattern utilizing long horizontal wells. Currently, a revised field redevelopment plan is being evaluated to assess increasing the production target of the reservoir while maintaining the production plateau. In order to sustain target oil production and improve recovery, the revised field redevelopment consists of different innovations including maximum reservoir contact (MRC) wells with line drive pattern, gas lift, infill drilling and co-development of multiple reservoirs with single lateral or dual lateral wells with different tubing strings and appropriate EOR technology.
This paper describes the current work to optimize the combined development plan of three vertically adjacent reservoirs by using multiple strings in a given well to access them. The focus was to revise the development plan of the larger reservoir and use the future development wells of this reservoir to access other smaller vertically adjacent reservoirs that are within the drilling reach from different artificial islands. The study addresses optimized well spacing, vertical well placement, well drill sequence and infill well placement. This study also includes assessment of the value of infill wells, dual-lateral and single-lateral wells to target more than one reservoir.
An optimized field development plan is formulated with new MRC wells which include both single and dual-lateral wells accessing one, two or three reservoirs depending upon location and applicability.
Assessment of Simultaneous Water and Gas Injection SWAG Pilot in a Giant Offshore Carbonate Reservoir
Authors: Chen Peng , Al Sowaidi Alunood K. , Patel Harshad , Brantferger Kenneth , Bin Buang Kamarul Ariffin , Syed Fahad I. , Shehhi Rashed Al 
Published: November 2016

Abstract
Gas injection has been widely used by industry for improving oil recovery. A common variation of gas injection is to have water-alternating-gas (WAG) injection which attempts to overcome gas override in an oil reservoir. In this paper, a simultaneous water and gas injection pilot is discussed. Water and gas are injected simultaneously using two strings in the same well with water injected into an upper zone and immiscible hydrocarbon lean gas injected into a lower zone. This is referred as SWAG in the paper.
The subject reservoir is part of a large field located offshore in the Middle East. Water flood started in this under-saturated oil reservoir since 1980’s. Five immiscible gas injection pilots (GIPs) including the SWAG pilot were initiated in late 2001 in this reservoir to assess the benefits of immiscible gas injection in improving oil recovery.
This paper describes the performance analysis from field surveillance data of the SWAG pilot which is also aided by a sector simulation model. Performance comparisons of the SWAG pilot versus the earlier completed gas injection pilots is also demonstrated. The history matched model successfully predicts gas arrival timing in the pattern producer. The model results are used to infer the swelling effect of the injected gas as well as to estimate gas sweep efficiency.
Both RST log and simulation results show that simultaneous water injection introduced in the upper zone is not able to mitigate gas override. The model analysis, coupled with results from special core analysis, suggests the immiscible gas is not as effective as water injection in maximizing oil recovery from this reservoir. The volumetric sweep efficiency of the injected immiscible gas is estimated to be less than 10% pore volume (PV) and the swelling benefit is less than 1% OOIP at the time of gas breakthrough.
Conceptual Study for Sour Gas Processing Emphasized on Acid Gas Injection
Authors: Haristyawan Rendra B. , Yuliatri Mira , Sugiarto I. Totok , Ringoringo Adi F. , Adhi Tri P. 
Published: November 2016

Abstract
Despite of its popularity as cleaner fuel natural gas exist in the ground occasionally contaminated with high contents of acid gases. Venting the acid gases from the resource is somehow unviable in the near future while many countries all over the world has pledged to reduce their greenhouse gas emissions. This study presents a conceptual approach for processing natural gas to address the acid gas injection option as the environmentally friendly manner to deal with in the development of highly contaminated natural gas, regardless the importance of the acid gas injection, storage, and field economics. Preliminary selection and comparison of gas processing technologies has been evaluated considering the proven technologies as well as the emerging cryogenic technologies. As the results a potential cost saving which may benefit to the field economics and higher process performance can be achieved by the emerging cryogenic technologies compared to current proven technologies as base case. The challenges is how making the technology feasible at commercial scale.
Application of Ultrashort Radius Lateral Drilling Technique in Top Thick Reservoir Exploitation after Long Term Water Flooding
Authors: Liu He , Huang Shouzhi , Sun Qiang , Ming Eryang , Li Tao , Han Weiye , Chen Qiang , Li Yiliang , Pei Xiaohan , Zhang Shaolin 
Published: November 2016

Abstract
Numbers of oil fields in China had entered high water cut stage. The inefficiency circulation happened frequently during water flooding of these oil fields because of seriously intraformational heterogeneity in thick reservoir. Based on oilfield development dynamic data, it indicated that the problems of inefficiency fluid injection and futility circulation could not be solved in vertical well exploitation, no matter using water flood or chemical flood. There was a certain thickness of unexploited or low flushing efficiency oil remained on the top of thick reservoir. The traditional lateral drilling techniques could not be applied in short radius within 5 1/2 inches to 7 inches casing which were regular casing sizes of injection well in these oil fields. To exploit remained oil, the recent method to increase flow conductivity was hydraulic jet technology. But it had several disadvantages, like small aperture diameter, short drilling distance, inaccuracy orientation and limited flow conductivity.
This paper introduces an ultrashort radius lateral drilling technique (URLD) which provides an efficient method to increase production by drilling into the target reservoir to build a flow channel between unexploited reservoir and wellbore. The ultrashort radius lateral drilling technique includes flexible lateral drilling tool, deflecting tool, directional tool, etc. The flexible lateral drilling tool, which is the key in URLD technique, is consisted of several flexible nipples in the length of 15 cm. It is connected by double offset universal joint between adjacent flexible nipples. The movable angle between adjacent flexible nipples is 4-6 degree. And a PDC drill bit is connected in front end of tool. The URLD technique can realize lateral drilling within 5 1/2 inches to 7 inches casing. It can be applied to target reservoir thicker than 2 m. The drilling track is controllable. Target error is within ±1 %. Minimum deflecting radius is 1.8 m. The drilling hole diameter is 114 mm. The length of lateral drilling is more than 100m in 5 1/2 inches casing and 200 m in 7 inches casing.
The URLD technique has applied in more than 20 wells in China, and barels oil per day increases by 3 to 5 times in average. The URLD technique provides a solution to exploit remained oil after long term water flooding, and increases the production of mature oil field in economical way.
Delivery, Acceptance and Mobalization of a New Built Offshore Lift Boat
Authors: Alyafei Othman 
Published: November 2016

Abstract
The majority of Offshore Accommodation Jack Up Barge units in the area operate in shallow water depth of 50-60 m. The accommodation barge serves offshore operations as a reliable unit facilitating all required work programs.
Dolphin Energy entered into an agreement with a local Qatari contractor in July 2014 to deliver a new build, self-propelled Offshore Jack up Barge to support maintenance, well services, and shutdown campaigns at Dolphin Energy’s Offshore production platforms operated in unmanned mode. The barge is considered to be the first locally built barge.
Dolphin Energy was involved from design and construction phases to the trial phase. It was possible to share the operational problems faced with the barge utilized in the past and address these for the new barge.
The purpose was to build a barge which could safely operate and efficiently support wide range of well intervention and construction activities offshore.
The contractor was able to construct and deliver effectively the required barge. The jacking up and sea trials were witnessed by Dolphin Energy’s Marine Team. The barge was then moved to offshore and jacked up on along side the Platform in February 2016.
This paper describes the challenges faced that were then overcome during the execution of the project.