bluuebunny/crossref_metadata_2025_split huggingface dataset:
Determining Trapped Gas Saturation and Effect on Recovery Factor in Carbonate Reservoir
Authors: Dotoku Shun , Hutagalung Danny Riau , Purba Victor Stephen , Jailani Djunaedi Tugiman 
Published: October 2019

Abstract
Trapped gas saturation is existing gas saturation after displacement by water and it is one of the key parameters for the estimation of gas recovery factor and gas production deliverability for the reservoir, especially gas reservoir under active water drive. This paper presents a case study of producing North Senoro gas field in Indonesia for series of experimental work of trapped gas saturation measurement and comparison with estimated trapped gas saturation using well-known correlation from various core experiments results. Effect of trapped gas saturation on gas recovery and gas production deliverability were also assessed in various sensitivity analysis using simulation model.
Trapped gas saturation varies with rock physical properties such as rock type, porosity, permeability and initial gas saturation and experiments method. Various core samples were chosen to cover range of rock properties in bulk of reservoir and we applied two experiment methods under spontaneous imbibition, Counter-Current Imbibition (CCI) and Co-Current Imbibition (COI). Measured trapped gas saturation had strongly dependency on permeability rather than porosity. The comparison between two methods illustrated that COI showed lower trapped gas saturation compared to CCI except the core plug with high permeability. Difference of measurement results between CCI and COI came from different boundary condition and flow regime between air and toluene during experiment. As co-currently flow regime by COI was closer to fluid behavior in reservoir condition compared to counter current flow regime by CCI, the results from COI was adopted for further analysis.
Both of CCI and COI results showed higher trapped gas saturation compared estimated one from Agarwal correlation which defined trapped gas saturation as a function of rock type, porosity, permeability and initial gas saturation. It indicated measurements for specific formation is necessary and critical, especially for complex carbonate formation instead of using correlation.
The measured data was utilized to analyze effect on recovery factor in North Senoro gas field as a case study. In simulation model, trapped gas saturation was defined as a function of permeability and initial gas saturation based on our experiment results and Land equation. Sensitivity analysis results concluded that effect of trapped gas saturation on gas recovery factor was limited without any aquifer drive meanwhile trapped gas saturation was critical under strong aquifer support because bulk of gas was trapped by water under high pressure and it kept abandonment pressure high at the end of production high.
In addition to accurate measurement of trapped gas saturation, clear understanding of aquifer strength is necessary for realistic gas recovery factor estimation and optimum development planning.
Locating and Quantifying Downhole Sand Production with Wireline Sand Detection Tool and Examples of Application in Wells Offshore Caspian Sea
Authors: Timonin Andrey , Mollaniyazov Eldar 
Published: October 2019

Abstract
Sand production in oil and gas wells is badly affecting production rates, damaging downhole and surface equipment. Knowledge of source of sand production and its amount can prolong well life by performing timely remedial operations. Nowadays, companies rely on stress analysis and numerical models to predict source of sand production in wells producing from several layers commingled and at the same time amount of sand production is measured on surface with separators.
On the other side, wireline sand detection tool allows to quantify and locate source of sand production downhole as well produces, and when run in combination with production logging tool string, to quantify multiphase inflow profile into the well simultaneously.
Most of the wells on Dzheitune (LAM) field, located offshore Caspian Sea, were completed with dual tubing at the beginning of field development. Over the time, depletion in reservoir pressure caused formation failure in A-sand reservoir and wells producing from this formation started to produce sand. Some wells had to be recompleted by pulling out of hole dual string completion and running in hole single tubing with sand screens across existing perforations. Before pulling dual tubing, some wells were logged with slim sonic tool to locate top of sand accumulation in casing to long tubing annulus. This information was used to determine depth for tubing cut, before pulling it out of hole; whenever such operation was required. Most of the newly drilled wells are completed with single tubing having sand screens.
Field examples, presented in this paper, describe principles of data acquisition with sand detection tool when run in combination with production logging string, and results of logging in slightly deviated wells completed with sand screens. Comparison of multi-phase inflow profiles with source of sand production showed that most of sand is being produced through hotspot in sand screens; i.e. eroded hole that was generally located across topmost section of the screens in almost all the wells that were logged. Logging results are then used for planning remedial operations to pull tubing out of hole and to replace damaged screens.
Implementation of Collaborative Workspace for Petrophysics Asset Teams By Promoting Centralized Project Data Management
Authors: Fareed Abdul , Tariq Aqeel , Sani Usman , Abdul Rehman Musab , Palekar Arshad Hussain , Ali Mutawassam , Khan Zeeshan , Akber Javed , Abduallah Ibrahim , Sharif Duria , Nisar Kashif , Sukendro Hendrie 
Published: October 2019

Abstract
In one of Operator; they want that Asset teams must work closely and collaboratively to achieve results in Petrophysics projects. A project data management (PDM) effort established a system that enables collaboration for petrophysical teams and that makes quality-controlled data available for each project. A separate of objective in the effort was the documentation of business rules for the petrophysical asset team.
Centralization of PDM is the key to enabling collaboration and the provision of quality-controlled data. Therefore, one focus of the project was centralization. While implementing the technology, the project team also prepared the "agreed" business rules document (BRD). This BRD will guide the petrophysical teams to properly maintain their project data. The BRD lays down standards and supports common understanding. Additional steps before the implementation of technology were performing QC and cleaning the existing data.
Centralization of the PDM enabled some key workflows, which cannot be achieved in standalone projects. Specific achievements of this project included enabling collaboration, retaining knowledge, setting up business rules, and performing quality control. Enabling collaboration was the key objective of the project. After the implementation, it was noted that using the system, team members can work on the same "physical" project without disturbing each other's work. Any updates in the project are communicated to the entire team. The updates are accompanied by user notes to enhance team understanding. Collaboration enables teamwork during the project timeline. However, for the E&P companies, it is also very important to keep the "knowledge alive" for later work on the same project by other teams. Long-term knowledge retention has been enabled by the ability to maintain captions, notes, and quality parameters. These "pieces of knowledge" will help future teams understand the thought process behind the results. Setting up the BRD enabled alignment of the end users, IT teams, and data management teams. The one-time quality assurance of the existing project data and raw data has aided the operator in implementing the centralized PDM and workflows.
Effective Solutions To Well Integrity Management Using Multi Finger Caliper And Electromagnetic Tool
Authors: Ajgou Nadir , Graba Bachir , Sayah Laid , Ismail Moustafa , Yakupov Alfir , Saada Mahmoud , Rourke Marvin , Abdelmoula Mongi 
Published: October 2019

Abstract
A multi-sensor magnetic thickness detector tool has been developed specifically for the corrosion evaluation of multi barrier pipes. The electromagnetic tool would be able to identify a metal reduction of each pipe individually. The tool is combinable with Multi-finger caliper, which provides three-dimensional profiling of the internal pipe. Combining both tools together would provide a better assessment of well integrity and corrosion management.
The magnetic thickness detector tool is based on the physics of pulse eddy currents. It can detect up to three barriers and measure circumferential average metal loss at each barrier. Simulation software with advanced modeling techniques will aid to identify corrosion extent through a comparison of simulated model decay curves with real tool response. The Multi-finger caliper tool provides direct measurements of internal tubing and casing diameters. The mechanically measuring fingers will move radially along the inner pipe wall, which provides accurate diameter change.
In this paper, we are presenting a case study where a magnetic thickness detector tool detected corrosion in the outer barrier and was able to provide both pipe assessments individually. These results have been confirmed with running Multi-finger caliper and showed that the first pipe was of good condition. Later on, the tubing was retrieved and circumferential acoustic scanning tool was run and confirmed the metal loss detected by magnetic thickness detector tool. Similar cases showed that the combinability of Multi-finger caliper and magnetic thickness detector tool would help to identify inner versus outer corrosion in which it would save both time and money through real-time operational interventions.
Challenges in Developing a Marginal Thin Sand Reservoir: A Case Study from South Sultanate of Oman of Unlocking Potential
Authors: Ma'Mary Talal , Al-Jumah Ali , Maskari Muna , Harrasi Ameera , Saadi Faisal 
Published: October 2019

AbstractThis paper discusses the multidisciplinary challenges faced while assessing and developing a thin sandstone reservoir with limited connectivity and no aquifer support, and how gathered data and surveillance, combined with tests and engineering sense, turned this reservoir into a feasible development, unlocking its full potential that was overseen earlier. A case study is presented with the Lessons learned to be replicated. The reservoir in question will be referred to as IRS.Picking and identifying the reservoir on openhole logs is difficult, as it has been overseen in the past. Few existing wells where logs are available have been re-assessed and IRS perforated and tested, yielding very positive results. Few dedicated horizontal wells were drilled with encouraging results, core has been acquired, and preparation for a water injection pilot is undergoing to close the loop with the pressure support story. All results are presented as a case study in this paperWhile targeting the main reservoirs in a development drilling for the field in question, a smaller opportunity (IRS reservoir) was identified in the buildup section of hundreds of horizontal wells. The immature IRS represents the upper most part of a main sand body. The sand is enclosed between the Upper and Lower major Shale layer. It is believed that it was formed at the latest stage of Glacial age when a large lake has formed and it was receiving sand influxes from surrounding highs due to ice melt forming what is called IRS in this paper. The Cretaceous marine Shale reservoir on top acts as a regional seal and lies on a regionally extensive unconformity. The IRS reservoir is laterally discontinuous and variable in thickness and rely on truncation underneath the cretaceous Shale as trapping mechanism. The attractiveness is the stable dry oil production combined with stable pressure drop. Preliminary encouraging production data of oil per well as compared to a regular development well, generally with low water cuts. Following the implementation of appraisal and study plan, supplemented by production tests and surveillance, more confidence is being built in IRS as a feasible development reservoir, with further assessment being carried out at the time of preparing this paper.Active development of IRS reservoir have been the attention of the authors for an extended period of time, the team of integrated disciplines has captured the development challenges from Geology, Petrophysics, Reservoir Engineering and Well Completion in a detailed manner with a clear path towards full exploitation of the reservoir. The authors trust their experience and approaches used are practices worth replicating and are captured in this paper.
Innovative Engineered Approach to Improve the Hydraulic Isolation and Wellbore Integrity Across Production Zone in Challenging HP Wells
Authors: Bugrayev Amanmammet , Nafikova Svetlana , Taoutaou Salim , Timonin Andrey , Gurbanov Guvanch , Rovshenov Gadam , El Sayed Mohamed , Hay Kevin 
Published: October 2019

Abstract
Complete and durable zonal isolation is the foremost goal of the cement job. In the deep and high-pressure environment, obtaining such goal is particularly critical, but also challenging due to the additional factors associated with the high drilling fluid densities that limit mud removal efficiency, narrow margins between fracture and pore pressures that cause loss circulation and differential sticking, and cement sheath exposure to downhole stresses during construction and production phases that compromises its integrity.
Careful planning is required to ensure all risks are captured and mitigated during the design stage, taking into consideration not only the construction phase, but also post-placement downhole conditions changes caused by temperature, pressure fluctuations, and mechanical shocks during perforation and stimulation operations.
Data analysis of the offset wells located in the eastern section of the Caspian shelf showed that conventional cement systems and previously applied cement job designs had limited success in addressing those challenging complex requirements. Thus, a new approach was required. This approach was used in 20 wells in the field with excellent results.
Two wells were used to demonstrate the improvements obtained in zonal isolation behind production liners upon implementation of new engineered methodology. The innovative complex approach involved not only the revision of the previously used cement and spacer fluid designs, but also required revisiting and evaluating every aspect of cementing practices to achieve the desired results. Fiber-based spacer technology was introduced to enhance mud displacement and an engineered flexible and expanding cement system to achieve and maintain well integrity.
Numerical analysis modelling was used to simulate the stresses that the cement sheath will experience over the well's life and calculate the minimum required mechanical properties of cement to be able to withstand these stresses. The set cement mechanical properties were then customized using a proprietary trimodal particle-size distribution technology to accommodate the expected downhole stresses. Hydraulic isolation improvement was achieved and confirmed by downhole logs.
Project Construction Modularization Assessment
Authors: Abdellatif Mohamed Sameh 
Published: October 2019

Abstract
The decision to use Modularization Vs Stick Built for project execution must be subject to proper assessment followed by Constructability Assessment to decide on the best way forward.
The Construction Modularization Assessment is the best process to decide. This exercise must be carried out during FEED taking into consideration the geographic site location, resource availability, logistics, constraints and limitations. The outcome of this exercise will determine the feasibility of modularization and estimate the number, type and weight of each module.
The build sequence is an important factor linked to this exercise and must be carefully studied to provide a clear plan linked to the estimated delivery dates of material and equipment with special attention to long delivery items in addition to assessing the risk of delays and provide alternative module installation sequence.
Conducting such assessment during FEED will have a major impact on Project successful delivery since it will provide the EPC Tenderers with clear methodology for fabrication and installation, however this assessment and proposed modularization scheme can always be modified by the EPC Contractor to suit his capabilities and resources.
Also, it worth highlighting that the assessment will identify the associated risks which will help the Contractor to be very competitive in his bid.
This paper is based mainly on lessons learned from implemented major onshore and offshore projects and accordingly reflects a practical approach which can be adopted for future projects.
It is to be noted that such assessment is not part of the standard formal reviews carried out by companies during FEED and mostly left to EPC Contractor to decide.
A Soft but Effective Strategy to Ensure Data Completeness and Data Quality
Authors: Diwakar Amitesh , Akoum Mohamed 
Published: October 2019

Abstract
In the Big Data and Artificial Intelligence (AI) era, Data Completeness and Data Quality are corner stones to get data insights. Among many projects in this field, ADNOC Onshore put in place a framework supported by a comprehensive Service Level Agreement to ensure that all data either internally generated by the company or acquired from our service providers are made available for the user's community to use after validating the Data Quality.
The outcome of this effort is a framework that defines the boundaries and the rules, which govern the data completeness and data quality in the organization. It is meant also to support the implementation of the technical tools, which are meant for this purpose. The Service Level Agreements covered all sub-surface, drilling and engineering data from initiation, to provisional data, to interpreted data to final and complete data that is required for AI and Data Analytics use by the end-users. The SLAs identified the role and the time allocated for each stakeholder to perform its job. A Dashboard has been developed to show the status of each data set in terms of completion within the stipulated time by the data owner, custodian and steward.
The Data Quality rules have been embedded in the SLAs terms to ensure reliable and trustworthy data. This foundation is a soft approach to support the system and various Data Management tools in facilitating data enrichment for comprehensive business value to ADNOC.
Case Studies of Expanding Cement to Improve Wellbore Sealing
Authors: Bugrayev Amanmammet , Nafikova Svetlana , Taoutaou Salim , Timonin Andrey , Gurbanov Guvanch , Burkenya Alexander , Amanova Irina , Hegab Mahomud 
Published: October 2019

Abstract
Good cement bond at the casing-cement and cement-formation interfaces is essential for effective zonal isolation. Poor bonding can lead to underground fluids and gases to enter the annulus and create sustained casing pressure (SCP), jeopardising the working envelope of the well and limiting its production. One of the causes of a poor cement-formation bonding is attributed to a cement shrinkage. Cement systems that expand after setting can help improve primary cementing job results by sealing microannulus. The enhanced bonding is the result of enhanced shear bond and adhesion of the cement against the pipe and formation.
Cement expansion is achieved by addition of the expanding additives into cement system. The mechanism of expansion is based on set cement volume growth over initial volume post setting. This is driven either by gas bubbles created during chemical reaction or by crystal growth within set cement matrix. Careful optimization of the cement slurry designs with an addition of the expansion additives to conventional and complex blend systems allowed greatly improving the cement bond evaluation log results without compromising other mechanical properties of cement.
This paper outlines the successful application of expanding cement to seal different sizes of wellbore; the study evaluates the effect of the expansion by comparing the cement evaluation log from numerous cementing jobs. Examples included in the comparison are cemented production strings (casings and liners) with different types of cement systems used across 9 5/8-in. production casings and 7-in. and 4 1/2-in. production liners.
Combined Sand/Water Control Polymer Treatment in Cheleken Offshore Oil Well Case Study
Authors: Kontarev Roman , Berdyev Yunus 
Published: October 2019

Abstract
A new polymer technology successfully implemented in one of offshore oil well.
The technique uses water-soluble polymers and microgels having a strong tendency to adsorb on the surface of the rock, thus forming a protective film to prevent the erosion process.
Many wells in this area are facing sand problems due to reservoir depletion and water entries. To avoid critical problem connected to sand production the most common action has been so far to reduce production rates by choking down the wells and recompleting the wells utilizing downhole sand-control solutions (sand-screens).
The common problem of sand-screen completed wells is mechanical screen damage due to high abrasive reservoir fluid velocity resulting resuming and even accelerating sand production to the surface.
Damaged section of sand-screens has been identified by utilizing sand-detection logging technique ran in hole by wireline and polymer sand consolidation treatment selectively placed by CTU across target zone.
Executed chemical treatment consist of injecting of water soluble polymers with the main objective to form an adsorbed polymer layer on the surface of the rock, thus providing sand/fine stabilization.
The products also have RPM properties (Relative Permeability Modifiers), i.e. they affect little oil relative permeability while reducing the relative permeability to water.
Field trial have been executed with the following results: Treatments were successful in stopping sand productionNo water production observed over the few month after the treatmentThe treatment helps to restore the production of the well shut-in more then 6 month due to extensive sand production.