bluuebunny/crossref_metadata_2025_split huggingface dataset:
Introducing New Shaly Sand Analysis Petrophysical Model for an Unconventional Reservoir Leads to Double the Volumes in a Brown Gas Field, Bahariya Formation, BED 2 Gas Field, Western Desert, Egypt
Authors: Mabrouk Ibrahim , El Bendary Ahmed , Magdy Mustafa , Bakr Ahmed , Ashraf Mohamed , Youssry Amira 
Published: October 2017

Abstract
BED 2 is a brown gas field located in the western desert, Egypt and commenced production 1982. The field has multiple reservoirs varying between carbonates, clean sand stone and shaly sand stone.
Baharyia formation is the main producing reservoir in the field. In the latest years of the field life, an unrealistic recovery factor was reached making the volume of the recovered gas exceeds the maximum volume that could be recovered from this reservoir.
Hence, a new further investigation and review for the previously calculated GIIP was initiated. The results of this study yielded that the main uncertainty in the volumetric calculations was the petrophysical evaluation subsequently a new unconventional petrophysical evaluation approach was performed.
The first step in the petrophysical evaluation was to use the core data to separate the rock into different rock types "hydraulic zones" by calculating the reservoir quality index (RQI) and the flow zone indicator (FZI). After that, an electro-facies model was created using the electric logs for the model input and the hydraulic zones derived from the core data as the model learning.
The resulted model matched the core data in all the four cored wells and hence it was applied to the un-cored ones.
After that, the created rock typing model was used to deduce the cut-off criteria per each rock unit which resulted a huge difference from the previously calculated cut-offs and hence the NTG ratio is doubled as three types of net sand were added to the petrophysical evaluation. The first type is a very silty highly laminated sand-shale reservoir while the second one was clean sand reservoir.
Conventional saturation calculation methods showed no match between the calculated volumes and production and hence different unconventional shaly sand analysis was used in calculating the saturation for the two different types of sands.
The new petrophysical evaluation resulted in doubling the volumes in Baharyia reservoir and so a perforation campaign was performed to confirm the new volumetric calculations, which showed a good match with the model results. Hence, a new well was drilled targeting the low quality sand and found them with high pressure almost near virgin pressure.
Design of a Partitioning Interwell Tracer Test for a Chemical EOR Pilot Targeting the Sabriyah Mauddud Carbonate Reservoir in Kuwait
Authors: Al-Murayri M. T. , Al-Qenae A.. , AlRukaibi D.. , Chatterjee M.. , Hewitt P.. 
Published: October 2017

AbstractThis paper sheds light on the design of a Partitioning Interwell Tracer Test (PITT) for a normal 5-spot chemical EOR pilot targeting the Sabriyah Mauddud (SAMA) carbonate reservoir in Kuwait. This pilot is currently going through the water pre-flush phase which will be followed by chemical injection in the near future.Due to recent improvements in the synthesis of partitioning tracers, water-based partitioning tracers can now be utilized to evaluate variations in oil saturation pre and post EOR applications as well as interwell connectivity for chemical EOR pilots. A PITT is planned to take place in support of a normal 5-spot chemical EOR pilot in the SAMA reservoir. Four unique passive tracers will be injected into the pilot injectors prior to better understand reservoir conformance. This will be followed by the co-injection of four passive-partitioning tracer sets to evaluate oil saturation before and after chemical injection.A fit-for-purpose facility set-up has been installed to perform quasi-simultaneous injection of different tracer packages into the four EOR pilot injectors and a robust sampling strategy was developed to analyze the produced fluids from the pilot producer and sampling observation well in addition to other offset producers surrounding the pilot area. Periodic lab analyses involving techniques such as Gas Chromatography coupled with Mass Spectroscopy (GC-MS) will be performed to analyze tracer breakthrough times, peaks, dispersion and partitioning-passive tracer relationships. The findings from this PITT will be used to develop a comprehensive understanding of oil distribution and inter-well connectivity within the pilot area to assess the techno-economic feasibility of multi-pattern chemical EOR deployment.This PITT in a major carbonate reservoir is one of the first reported field cases to evaluate variations in oil saturation and interwell connectivity for subsurface chemical EOR applications in a normal 5-spot pattern pilot area.
Installation of a Sucker Rod Pumping System Over a Failed Progressive Cavity Pump to Recover Production Using Rigless Intervention - Burgan Field - South East Kuwait
Authors: El-Dousary A.. , Al-Adwani H.. , Sierra T.. , Solaeche F. Ledesma , Darwish W. S. , Khan F.. 
Published: October 2017

Abstract
The current competitive market conditions in the oil industry and company’s shoestring budgets call for methods to recover crude from wells with minimum costs. This paper focuses on the design, rigless installation, and successful results of a sucker rod pump (SRP) system after the failure of the existing progressive cavity pump (PCP).
The subject well had a PCP at 4,248.05 ft. setting depth failed after 60 days due to a broken rotor. Attempts to fish the parted rotor were unsuccessful. To avoid a workover rig and to reduce non-productive time (NPT), a SRP system with an insert pump anchor was set over the failed PCP system at 4,028 ft. via a flush by unit. A tubing punch job from 4,085 to 4,145 ft. was done for allowing the fluid entering the tubing and passing through the SRP system.
Running a SRP with an insert pump anchor enabled the pump to be set at any depth inside the tubing, above the failed PCP system. Successful installation of the SRP system reduced NPT and standby costs, and eliminated the need for a workover rig. While running the SRP system, the production enhanced by 50% more than the PCP’s maximum recorded rate. On the other hand, the pump can be retrieved and/or the artificial lift method can be converted later on without the requirement of a workover rig.
In Burgan field, Kuwait, the first rigless installation of a sucker rod pump over a failed progressive cavity pump has turned into the reference for methods of how to recover oil when other artificial-lift systems fail.
Realtime Reservoir Fluid Characterization Using High Efficiency Gas Extraction Membrane Technology System and Advanced GC Tracer Chromatograph; A Case Study from East Kuwait Jurassic Reservoir
Authors: Rane Nitin , Ahsan Javed Mohamed , Turkey Shaikha , Datta Kalyanbrat , Al-Nasheet Anwar , Al-Sabea Salem , Al-Mahmeed Fatma , Moustafa Ahmed , Guettal Miloud 
Published: October 2017

Abstract
One of the first sources for formation evaluation while drilling a well is the gas data provided by the mud logging services, that is used increasingly as preliminary real-time reservoir interpretation to identify gas-oil or oil-water contacts, reservoir entry points, lithological changes and other applications.
Gas ratio analysis and interpretation is a very valuable formation evaluation tool for geologists and petrophysicists to characterize the hydrocarbon fluid types and rock properties. Gas ratios when used in combination with wireline or logging while drilling tools can help resolve uncertainties that otherwise could only be resolved by testing a well. Jurassic deeper wells (&gt;11000 ft) with a varying pressure regimes, very often the wireline logging or Logging while drilling (LWD) logs are cancelled due to several drilling related complications especially mud gain/loss situations. In these wells, Gas while drilling becomes a very unique and important tool that can provide significant insight into the reservoir properties. The gases liberated from the formation at the surface helps us determine the composition of the reservoir fluids and also provides information about the lithological changes, water saturation, and the mobility of the hydrocarbons contained into the rock. This broad spectrum of hydrocarbons assisted by the surface gas analyzer allows the separation of producible mobile heavy hydrocarbons from water wet zones. This ability to differentiate allows operators to geosteer a horizontal well in thin units of potential reservoirs by avoiding water bearing zones and staying in producible hydrocarbon zones. The end result is the ability to intersect the maximum amount of net pay in the target zones.
This paper highlights the case studies from deeper reservoirs of East Kuwait where a surface gas logging system employing a semi-permeable membrane extractor coupled with an advanced GC tracer chromatograph detector has been applied in some of wells drilled in Greater Burgan Magwa Marrat limestone reservoir. Advanced gas logging system was deployed in two vertical/deviated wells to characterize the gas ratios for the different units/zones of Marrat reservoir. The zonation from Gas ratio interpretation was validated with the available wireline logging data before using it for planning the horizontal well. The GWD and LWD were performed independently of each other to determine the effectiveness and reliability of the GWD method. GWD in conjunction with LWD was used for the first time in Kuwait to place a horizontal well in a thin (15-20 ft) layer of a deep Marrat reservoir. Use of realtime Gas ratio data and analysis, successfully helped to complete the well as planned high producer.
Application of a Multiple Attribute Decision Making Method to Improve Oil and Gas Field Development Projects
Authors: Passalacqua Herminio , Ortiz-Volcan Jose Luis , Al Einawi Mohamad Hasan , Kadnaji Jamaneh Mostafa , Karam Fatemah 
Published: October 2017

Abstract
This paper presents the application of a Multiple Attribute Decision Making (MADM) method based on the Analytical Hierarchy Process (AHP), a technique developed by Saaty, T.L. (1980, 2008), to improve definition of field development projects at early stages, when facing the challenge of selecting the best development option from multiple alternatives.
In order to rank efficiently various alternatives of development we apply AHP to technical quantitative or qualitative criteria, like EOR options, well types options, facilities options, transport options, operability and reliability, subsurface conditions, as well as economical quantitative parameters, such as Life Cycle Costing (LCC).
The AHP methodology supports decision-making using pairwise comparison of two or more criteria previously established by experts. For the application of this method, it is necessary to decompose the problem into several steps. In this paper, we show how to apply the method for the selection of a development option for a heavy oil field.
AHP applied to Front End Loading (FEL) staged-gate process increases the probability of success in generation of economic return and mitigation of major capital project risks faced during the early stages of the project. We discuss the advantages and disadvantages of this method with respect to other more conventional techniques.
The objective of this work is to introduce the use of the AHP methodology for the FEL screening phase with a simple exercise using information taken from the existing literature. At no time is this intended to be a complete guide for FEL applications.
A Novel Approach for Handling Unstable Wara Shale in Sabiriyah Field, North Kuwait
Authors: Nair Sajan , Alam Harry , Sitinjak Eri Sarmantua , Nugroho Cahyo 
Published: October 2017

AbstractThis article attempts to summarize measures that are required to be adopted in order to have safe drilling practices mainly in unstable shale formation and have a smooth landing section in target reservoir below the shale. For the last three years in North Kuwait, the number of geo-steering jobs increased significantly and some encountered problems while drilling Wara shale that may end up in losing tools and eventually the hole itself. This paper focuses on information regarding problems encountered in geo-steering jobs and the best practices followed to achieve goals. Stratigraphically, Wara shale lies underlying Tuba and overlying Mauddud carbonates. It has thickness variation in between 80 to 110 feet TVD. Wara shale in North Kuwait is generally unstable and very sensitive to mud properties and creates instability of the wellbore. A wide range of drilling data from well placement jobs were documented and analyzed in order to get an idea of the behavior of shale section, how to drill safely across this layer and mitigate possible risks that may harm the well as well as the tool. Detailed scrutiny was done to compare the drilling parameters, log responses, inclination and trajectory direction between stable and unstable wells. The results were integrated with regional tectonic regime in the area. The methodology and learning curve continuously improved with assimilation of new drilling data and information. Integrated study on all aspects in drilling that involving geo-steering engineers, drilling team, geologists and field engineers on-site has enhanced the ability to understand the situation in the hole and ultimately able to provide faster decision. It was observed that there is strong relationship of building inclination, direction of the well and mud weight in some wells when crossing Wara shale. Wells that have East - West or Northwest - Southeast direction tend to be unstable when compared to wells in North - South or Northeast - Southwest direction. Low incident angle (high inclination) will mostly cause more problems in drilling than high incident angle due to longer section of exposure as well as overburden. Compressional tectonic regime of the area dictate the recommendation of well trajectory should go towards maximum horizontal stress. Recommended to cross it with low inclination and consequently approaching the target reservoir with high dogleg severity tool was to maintain the stability of the wellbore. These findings will help service provider and client to make proper planning, adopt best practice, take proper decision and thereby successfully execute well operations. Indeed saving rig and delivery time that fulfill business objectives as planned.
An Engineered Workflow to Optimize an Openhole Multistage Acid Frac Design in Unconventional Horizontal Wells in North Kuwait
Authors: Ashqar Ayham , Chin Chao , El-Aziz Sabry Abd , Al-Ajmi Moudi , Robles Fernando , Mauro Rick , Nada Mohamed 
Published: October 2017

Abstract
Openhole (OH) multistage (MS) technologies can maximize reservoir contact and productivity by optimizing the distribution of acid across the formation matrix. Successful completion of these reservoirs can be challenging. This paper discusses the recommended practice for optimizing OH fracture stages and cluster placement distribution within heterogeneous unconventional oil carbonate reservoirs based on formation, completion properties, and reservoir fluid distribution.
Completion technology is based on distributing intelligent packers along the lateral section to develop the MS fracturing stages. Intelligent packer displacement influences fracture effectiveness and conductivity. Typical packer placement can undermine formation potential and productivity results. Packers and their ports are placed based on the formation's petrophysical and mechanical properties to increase the cumulative production in a shorter timeframe and help improve recovery. The workflow followed was based on analysis of the reservoir properties (porosity and permeability). These were later integrated with the measured rock mechanical properties. The developed integrated model was used to divide the rock into segments that share similar properties.
The use of an advanced azimuthal sonic with a high signal-to-noise ratio and wider frequency response helped improve the accuracy in assessing formation mechanical properties. Additionally, conventional logs, when combined with formation mobility measurements, help calibrate the permeability model and classify the formation into distinctive clusters. These clusters are then grouped according to their mechanical and brittleness properties to form a separate unit with a selected fracture port to help ensure the necessary fracture length. The developed method provides an opportunity to determine the necessary fracture stages and reduce the risks of over or underplacement. It also improves stage integrity, helps ensure better distribution of the acid across the formation matrix, and provides effective propagation of the fracture network.
The applied procedure follows an innovative workflow to optimize the fracture stage and cluster placement distribution across the reservoir using a new combination of advanced and conventional data acquisition and interpretation. The discussed case study demonstrates the benefits of engineered fracturing stage placement compared to a geometric displacement.
Sour Gas Compositions from the Analysis of Core Samples
Authors: Nederlof Peter , Fiorentini Pietro 
Published: October 2017

AbstractA detailed understanding of the composition of sour gas accumulations is essential for facility design and for production forecasting. Compositional data like H2S and CO2 contents, net sales gas volume and condensate gas ratio also form the basis for all project economics. The acquisition of high quality fluid compositions is therefore a priority in all sour gas well evaluations. For conventional gas accumulations, PVT analysis of down-hole or well-head samples provides accurate and representative compositions of reservoir fluids. But in many sour gas accumulations, like the Marrat in North Kuwait, the prediction of future production streams is a difficult task. H2S levels are highly variable and the ‘point measurements’ from MDT fluid samples may not be representative for the entire reservoir unit. This paper describes a new approach to derive gas compositions from the analysis of core samples so that PVT compositions can independently be verified and H2S concentrations can be extrapolated away from the down-hole sampling points. The method is illustrated with two wells from an ultra-sour gas field in the Arabian Gulf region.Core and cuttings samples from gas reservoirs contain trace amounts of adsorbed gas and condensate, which can be thermally extracted. The desorbed fluids can then be analyzed using existing geochemical technology and the molecular compositions of the condensate can be used to derive the composition of the gas that was trapped in the reservoir. Carbon isotope ratios can be measured on the gas that is desorbed from core samples and provide a second, independent parameter to estimate the original gas composition. The obtained fluid distributions are used to reconstruct the filling history of the sour gas accumulation.The isotopic signature of the gas, together with the composition of the organo-sulfur compounds in the condensate, allow the reconstruction of fluid compositions, which are a critical input parameter for the reservoir simulators. Combining the results from the geochemical analysis with existing PVT data allows the extrapolation of the fluid compositions and the reconstruction the field-wide compositional gradients.With H2S and CO2 concentrations varying between 5 and 35%, the production forecasting of sour gas accumulations can be subject to large uncertainties. Reconstructing the gas compositions from core and cuttings samples with geochemical techniques substantially reduces these uncertainties.
Engineered Bit Design and Drilling Parameters Mark Breakthrough Drilling Performance in Interbedded Damaging Carbonates
Authors: Agawani Waleed , Al-Ajmi Abdullah M. , Fawaz Wasim , Al-Rushoud Abdulaziz , Pandya Mehul , Al-Haj Hussain Ali , Abdelhamid Atef , El-Sherif Mohammed 
Published: October 2017

Abstract
West Kuwait's 22-in. section comprises a vertical hole through 3,500 feet of interbedded carbonates varying significantly in compressive strength, and drilled commonly with minimal or no fluid returns. The section is typically drilled with roller-cone tungsten carbide insert (TCI) bits because large polycrystalline diamond compact (PDC) bits are extremely costly and require expensive performance motors to support their generated torque. PDC bits are also at risk of impact damage when drilling through the interbedded formations in this interval. Operators tend to apply higher drilling parameters while in the lower compressive strength intervals to achieve higher rates of penetration (ROP). Consequently, when the TCI bit enters the following harder formations with the same high operating parameters, it often suffers severe cutting structure damage. The result is reduced ROP. Greater weight on bit is then applied, causing further bit damage and possible sealed bearing failure.
An engineering project was launched to develop a TCI bit specifically for the interbedded carbonates of this section. The primary challenges of the project were:
Ensure the bit finishes the section in one run Improve dull condition of bit coming out of hole Surpass current field average ROP consistently Maintain efficient cleaning at lower flow rates for drilling in complete fluid-loss scenario
Based on data and experience in drilling the application, an engineering process took place where several designs improvements with potential to improve performance were identified and trialled. Field engineers then worked onsite to identify how to drill the interval with optimal parameters for each sub-layer. The final design included:
Specialized TCI cutting structure for carbonate drilling High impact-resistant insert geometry Simulated hydraulic efficiency to improve hole cleaning Improved high aspect ratio elastomer seals designed to endure longer runs Specialized tungsten carbide to improve cutting structure durability
The engineering process yielded a design that successfully drills the complete section in one fast run - the fastest of the section - with an improved field average penetration rate to 63%, saving the operator more than 38% in associated cost for drilling the section. The application-engineered cutting structure enabled the use of lower drilling parameters than normal, thereby improving drilling efficiency and enhancing the post-drilling dull condition from the average of 3-3-BT to 1-2-WT.
The paper shows a case study in Kuwait demonstrating the engineering and results of designing a TCI bit matched to application.