bluuebunny/crossref_metadata_2025_split huggingface dataset:
Design Methodology for Swellable Elastomer Packers in Fracturing Operations
Authors: Evers Rutger , Young Dustin , Vargus Greg , Solhaug Kristian 
Published: September 2008

Abstract
During past 7 years, swellable elastomer technology has been introduced to the oilfield, and its acceptance has been so rapid that its scope of application has rapidly expanded. Swellable technology employs the principle of elastomeric expansion in hydrocarbon or water to form a permanent seal. With the increasing acceptance of this concept for the oilfield, new applications are being explored, and this paper will discuss the application of swellable elastomer packers (SEPs) in stimulation operations. These applications include acid stimulations and/or hydraulic fracturing operations. During stimulation operations, SEPs are subjected to a very specific set of conditions that significantly affect the sealing performance of the tool(s).
Three primary challenges must be addressed when designing SEPs for stimulation applications: The downhole conditions; i.e., the main parameters to which the tool will be subjected such as the downhole pressure and the average temperature of the sealing elements.Anchoring forces; i.e., the forces that occur from the shrinkage of the pipe during the treatment that subject the SEPs to additional forces that do not occur in conventional zonal-isolation applications.Thermal contraction of the sealing element; i.e., the contraction that occurs due to the injection of the stimulation fluids that will cause the temperature of the packer to drop. This phenomenon causes the sealing element to partially contract and will result in altered sealing properties, and ultimately, the loss of the pressure seal.
This paper describes the technical challenges and discusses resulting design methodology based on modeling (downhole parameters, anchoring forces) and laboratory testing (thermal contraction measurements) that have been developed to resolve these issues. This design methodology is not limited to stimulation applications but is applicable to any scenario with dynamic loads on SEP applications such as in water injection wells, etc.
Finally, case histories are provided to illustrate the successes that have been achieved using the design methodology described.
Completion of a Horizontal Well With Swellable Packers To Control Water Production
Authors: Cooper Katrina , McVey Adrienne , Schafer Daniel , Cox J. D. , Hilleary Nathan , Parker Donald , Crooks John 
Published: September 2008

Abstract
A long horizontal sidetrack, Well 01, was drilled into the thin Sag River formation in the Prudhoe Bay field in Alaska. Original plans included a well completion with a simple slotted liner. However, lost circulation and water-swept zones in the production section made a solid, cemented, and perforated completion necessary. At a certain point of total losses in the drilling of the well, seawater replaced the original drilling fluid. This allowed the well to be drilled, but complicated log interpretation and perforation placement from the seawater invasion.
There was a risk of a channel developing in the cement along the top of the well during the primary cement job due to the length of the horizontal section. A swept and faulted section in the middle of the well held the largest risk of excessive water production, therefore four packers which swell in specific reservoir fluids helped isolate this problematic section from a possible channel.
The horizontal length of the well, the high risk of losses, and the four swellable packers made the cement job challenging. The completion team had several options available for the cement job. The team ultimately chose a one stage job with additional excess volume and loss circulation material added. Closely monitored returns ensured the accuracy of the cement calculations, and a back-up plan for a top-down job was available if needed. The ultimate success of the primary job made the back-up plan unnecessary. After completing the primary cement job, just over 1300 feet of perforations were shot in the well.
The ability to change completion plans at the last minute allowed the installation of a successful completion with swellable packers which controlled water production. Also, an effective cement job proved possible even with multiple swellable packers in the well. Well 01 initially tested at just over 1000 barrels of oil per day with a 24% watercut. Currently the watercut remains at approximately 50%.
Acquiring Microresistivity Borehole Images in Deviated and Horizontal Wells Using Shuttle-Deployed Memory Tools
Authors: Christie R. , Elkington P. A. S. , McIlreath I. , Natros T. 
Published: September 2008

Abstract
Borehole images have broad applications in geological, petrophysical, and geomechanical studies. The advent of the small-diameter memory resistivity micro imaging tool improves operational efficiency in a broad range of well types. In spite of the tool's small size and weight, its design provides coverage and image quality that matches or exceeds that of previous generation imaging tools. It is deployed with or without a wireline and is not constrained by wireline data transmission rates because data are recorded to internal memory. Deploying the tool inside the drillpipe on the well shuttle facilitates access into highly deviated wells and past bad hole conditions without compromising borehole coverage.
Finding fractures in deep and tight rocks has become a high priority among explorationists around the world. Recent discoveries have shown that fractures can play an important role in the productivity of low-permeability plays, such as coalbed methane or shale gas. The only logging technology with the resolution to detect and identify these small features within the reservoirs is borehole imaging, where 2 mm details can be visualized.
Deviated wells in the Western Canadian Sedimentary Basin were logged using memory borehole imaging tools. The tools were housed inside a special drill collar while running in the hole, allowing rotation and circulation and were deployed using a messenger system and pressure pulses. The tools recorded microresistivity data to memory as the drillpipe was then tripped to surface. In all wells data was recovered, processed, and interpreted using software specially developed for this new memory-based technology. The resulting images were the equal of electrical borehole images obtained using conventional wireline deployment.
Using the memory imaging tool housed in the special drill collars protects the tools while tripping into the well. Since there is no wireline and no wet latches the shuttle system is more robust than conventional tool-pusher systems. This reduces risk and logging operation time while simultaneously delivering high-resolution borehole images that allow these fractured reservoirs to be properly evaluated.
Dual Laser Scheme Revolutionizes DTS Deployments
Authors: Jaaskelainen Mikko , Suh Kwang , Lee Chung 
Published: September 2008

Abstract
Distributed Temperature Sensing (DTS) systems have offered oil and gas companies critical asset monitoring solutions for years. DTS monitoring solutions provide real-time, dynamic temperature data with high accuracy, fine resolution and fast measurement speeds. DTS systems can provide tens of thousands of discrete temperature measurement readings along the complete length of an optical sensing fiber. These systems provide significant cost savings by identifying the location of leaks, optimizing gas lift operations, identifying under-performing zones, and monitoring thermal changes in steam drive applications. This paper discloses the first truly self-correcting DTS solution, which incorporates a revolutionary dual laser technology. This technology provides energy companies with the simplest, fastest, and most reliable DTS deployment available to the industry, combined with a capability to automatically correct for dynamic changes to the sensing fiber.
Successful Relief Well Drilling Utilizing Gyroscopic MWD (GMWD) for Re Entry into an Existing Cased Hole
Authors: Maehs Juergen , MacAfee Doug , Renne Steve , Cellos Greg , Srinivasan Ananth 
Published: September 2008

Abstract
In late 2007, a blow out occured in a well in the Gulf of Mexico. The blow out was caused by a leak in the production casing, which broached the surface and caused the well structure to collapse.
This SPE paper describes how the Apache Corporation utilized the latest state of the art Gyroscopic Measurement While Drilling (GMWD) tools to drill a relief well to stop the blow-out.
The S-shaped relief well was drilled towards the blow-out-well to perform a planned wellbore intersection. When reaching the blow out well, the production casing was milled and kill weight mud was pumped. This action stopped the blow out and enabled the operator to regain full control over the wellbore.
This paper also emphasizes the challenges while drilling this re-entry well: A 800 ft portion of the relief well had to be drilled with a closure distance of less than 40 ft to the pilot hole. Conventional MWD drilling systems which base their measurements on earth's magnetic field are incapable of providing reliable readings in areas with magnetic interference. Proximity to casing hinders the ability of conventional MWD tools to function and therefore, a drilling BHA with an integrating rate GyroMWD (GMWD) was deployed in this well. Rate gyro measurements are based on the earth's spin axis and can provide accurate real time survey data, including true north toolface and azimuth where earth's magnetic field is distorted.
This paper details an efficient way to drill a relief well and focuses on the innovative GyroMWD (GMWD) instrument that works in magnetic environments and close to metal casings.
The Use of Composite Materials in Repairing and Reinforcing Pipelines, Piping, and Structures
Authors: Rowe Adam , Alexander Chris 
Published: September 2008

Abstract
The purpose of this paper is to provide the oil and gas industry with an evaluation of composite repair and reinforcement systems to properly evaluate how composite materials should be used to repair and reinforce high pressure pipelines and offshore risers. The contents of the paper will include discussions on what critical elements should be evaluated for each composite system, items of caution and concern, and the importance of evaluation to ensure safe longterm performance. Based on a review of available research, composite materials can be used to reinforce damaged pipe materials. Specific examples include reinforcing mechanical damage subjected to cyclic pressure service and reinforcing corroded offshore risers.
Insights gained through the past decade can be used to apply composite repair technology to new systems and structures. The pipeline industry has led the use of these materials as a repair method in the same way the aerospace industry adopted this technology in the 1960s and 1970s. Using a "lessons learned" approach better positions us to understand the capabilities and limitations of this technology.
Detecting Thief Zones in Carbonate Reservoirs by Integrating Borehole Images with Dynamic Measurements
Authors: Li Bingjian , Najeh Hamad , Lantz Jim , Ali Rampurawala Mansoor , Gok Ihsan , Al-Khabbaz Mohammed 
Published: September 2008

Abstract
One of the key issues in creating a good reservoir model in carbonate reservoirs is the identification of the horizontal permeability conduits— "thief zones"— if any. In the Sabriyah field in Kuwait, dynamic measurements showed evidence of thief zones in the Mauddud formation. Early water breakthrough has occurred in some wells. Previous studies indicated that it was very challenging to detect the thinly layered thief zones using conventional openhole logs. This paper describes a methodology of recognizing the different types of thief zones in the Mauddud carbonate reservoirs using high-resolution image logs with calibration from core and dynamic measurements and by integrating image logs with nuclear magnetic resonance (NMR) and conventional openhole logs.
The Mauddud carbonates are Early Aptian in age and consist of grainstones, wackstones, and mudstones deposited in a ramp setting. Observations from production logging tool (PLT) and production data indicated that there are a few thief zones in different levels within the vertical Mauddud sequence. A previous core study shows that the fractures in Mauddud formation are short (&lt;10 cm) and concentrated in diagenetically cemented layers. The fractured thin layers are believed to be the principal type of thief zone. Another type of thief zone is associated with better-developed vuggy porosity. This study shows both fractured and vuggy porosity–related types of thief zones can be potentially detected through integration of high-resolution image logs with PLT, NMR, and conventional logs. In addition, methodologies of estimating fracture permeability and porosity-related permeability based on logs are also proposed. The log-estimated permeability determined using this approach fits better with the production profile and can then be used to evaluate the thief zones in a more quantitative manner.
Nuclear Energy for Unconventional Fossil-Fuel Resource Recovery
Authors: Badruzzaman A. , Hedges J. , Demayo T. , Sigworth H. 
Published: September 2008

Abstract
Nuclear energy is typically used to supply electricity, but a new generation of novel, inherently safer reactors can supply high-temperature steam for a number of petroleum, coal and chemical industry applications. Potential applications include recovery from unconventional petroleum sources such as oil sands and heavy oil, coal-to-liquids conversion, and production of hydrogen for refineries, chemical industries and possibly future transportation. Currently, natural gas is the typical source of the process heat and its use in these applications is likely to increase, as a greater reliance is placed on these resources to meet the projected growth in energy demand. This will increase greenhouse emissions from fossil fuel use. Techniques, such as carbon dioxide capture and sequestration, proposed to mitigate greenhouse gas emission from fossil-fuel based power and heat generation are in early stages of development and face technical and economic challenges. Nuclear power and heat generation emits almost no greenhouse gases. In addition, use of nuclear energy can free-up fossil fuels for other unique applications. These advantages, together with energy security concerns, improved safety and reliability, and reduced cost of nuclear plants, have renewed interest in this technology.
The paper explores the potential benefits and challenges of using nuclear energy in enhanced recovery from unconventional fossil-fuel resources. The associated economics and corresponding potential reduction in CO2 emission are examined. Both appear substantial in some applications, such as production from heavy oil reservoirs and oil sands. Economic benefits are more questionable in other applications such as in hydrogen production, and would require technological breakthroughs. Challenges facing nuclear energy include concerns of proliferation, waste disposal, public perception, demands on various resources, and licensing of novel high-temperature reactors. Resolution of power and temperature rating compatibility issues and siting constraints which may arise in some of the unconventional recovery operations will be additional challenges. However, these challenges may be less inhibiting than previously thought. The paper also briefly summarizes government-industry initiatives being discussed in the US to develop novel nuclear reactor concepts for these uses.
Experimental Study and Modeling of Cuttings Transport Using Foam with Drillpipe Rotation
Authors: Duan Mingqin , Miska Stefan , Yu Mengjiao , Takach Nicholas , Ahmed Ramadan , Hallman John 
Published: September 2008

Abstract
Although rotary drilling is being used in most wells, the impact of drillpipe rotation on hole cleaning during foam drilling has not been investigated. There has been no single predictive tool developed to address pipe rotation effects on foam drilling. This paper presents the first study of cuttings transport using foam with pipe rotation under simulated downhole conditions.
A field-scale, high pressure high temperature wellbore simulator with a 73-ft long, 5.76″ by 3.5″ eccentric annular test section was used to investigate the effects of pipe rotation, foam quality and velocity, downhole pressure and temperature on cuttings transport and pressure losses in a horizontal wellbore. Experiments were conducted with backpressures from 100 to 400 psi and temperatures from 80 to 160 degrees F. Pipe rotary speeds were varied from 0 to 120 RPM with foam qualities ranging from 60% to 90% and foam velocities from 2 to 5 ft/s.
It was found that pipe rotation not only significantly decreases cuttings concentration in a horizontal annulus but also results in a considerable reduction in frictional pressure loss. The reduction in cuttings concentration is up to 40% at a medium foam velocity (3 ft/s) when pipe is rotated up to 120 RPM. The decrease in frictional pressure loss is up to 50% at a medium foam velocity and is more than 60% at a low velocity. Using a higher foam velocity or quality also improves hole cleaning, however, pressure losses are significantly increased.
A mechanistic model and an associated computer simulator were developed for practical design and field applications. It can be used to predict cuttings concentration, bed height and pressure drop during horizontal foam drilling with various pipe rotary speeds, eccentricities, foam qualities and velocities under different pressure and temperature conditions. Comparisons between model predictions and experimental results show that the difference is less than 15% in most of the cases.
Effect of Porosity and Permeability on the Membrane Efficiency of Shales
Authors: Osuji Collins E. , Chenevert Martin E. , Sharma Mukul M. 
Published: September 2008

Abstract
This paper presents experimental data showing the dependence of shale membrane efficiency of water-base muds on its petrophysical properties and mud composition. Wellbore instability often occurs as a result of osmotic pressures that develop when shale is in contact with water-base muds. The osmotic pressures generated are proportional to the shale membrane efficiency. It is not currently possible to directly measure the shale membrane efficiency downhole. A pressure transmission technique was used to measure the membrane efficiency of Atoka shale at different porosities. This provides a way to estimate shale membrane efficiency from wireline measurements. The results of this study could possibly be used to design muds that cause shale strengthening and result in better wellbore stability.
Two series of tests were performed; the first used brine solution as the test fluid while the second used three industry-provided water-base muds. Results show that the membrane efficiency of Atoka shale ranges from 0.4% to about 13% and is a function of the shale porosity. This shows that the porosity of the shale itself is an important consideration in mud design. The data clearly show that the membrane efficiency is negatively correlated with the shale porosity until about a porosity of 7.5% beyond which there is essentially no change in membrane efficiency. A good correlation was also found between the shale permeability (which is in the order of 0.1 nD) and the membrane efficiency. Beyond a permeability of 0.2 nD osmotic effects are small.
For tests conducted with water-base muds, the membrane efficiency of the shale was reduced by a factor of more than 2 after contacting two of the three muds with the mud-altered Atoka shale. This decrease was found to correlate very well with an increase in porosity and permeability in the shale. However, muds which reduced the permeability recorded an increase in membrane efficiency. This shows the importance of porosity and permeability reducing agents in changing the membrane efficiency and osmotic pressure in shales.
Shale membrane efficiency has been shown to correlate with the shale porosity and permeability. Interaction of the shale with different water-base muds is shown to change the membrane properties of the shale. Furthermore, the nature of this change determines the effectiveness of these muds in the stabilization of troublesome shales. This is important because of the time dependent nature of wellbore failure. This study shows that certain drilling fluids have the ability to alter the shale through permeability reduction induced by osmotic flow. The results of the study can be used to better design water-base drilling fluids that will stabilize shales.
Characterization of Reservoir Heterogeneity through Fluid Movement Monitoring With Deep Electromagnetic and Pressure Measurements
Authors: Zhan Lang , Kuchuk Fikri , Ma S. Mark , Al-Shahri Ali M. , Ramakrishnan T. S. , Altundas Y. B. , Zeybek Murat , Manin Yves , Tartaras Efthimios , de Loubens Romain , Chugunov Nikita 
Published: September 2008

Abstract
Cores, open hole logs, formation testers, pressure transient tests, and production logs are usually used to assess reservoir heterogeneity. A common limitation of these techniques is that they do not provide two-dimensional spatial information of reservoir characteristics. For example, cores and logs have excellent vertical resolutions, but very small lateral radii of investigation, and the pressure transient tests have a large lateral radius of investigation, but very poor vertical resolution. Constructing an appropriate simulation model requires rescaling the data, and that may introduce significant uncertainties. To address these limitations, we explored the use of electrode resistivity array (ERA) measurements in a carbonate formation for reservoir characterization. The ERA was installed on tubing in a barefoot well rather than permanently cemented outside the casing as in previous applications. This notable difference introduced particular issues in the ERA data acquisition and interpretation, but also provided flexibility for device installation and operation. Furthermore, the ERA measurements were carried out in conjunction with low-salinity water injection and production in the same well. It was found that the ERA voltages near a source electrode showed unique characteristics that represented local formation heterogeneity. Although the new technology can be used at any scale, the focus was on characterizing formation heterogeneity within the length of the ERA string in the vertical direction and about 100 ft laterally around the wellbore. The scale of the investigated formation heterogeneity is comparable to grid sizes used in current reservoir simulations. Models were developed to identify stratified permeability heterogeneities from the time-lapse ERA voltages. The stratified heterogeneity estimated from the ERA measurements was compared to and verified by open hole logs and core analyses. The final heterogeneous reservoir model from ERA was subsequently applied to a numerical simulation that integrated the dynamic fluid flow, salt transport, and electrode array responses for water front monitoring and multiphase formation property evaluation and confirmed the first pass estimates of the identified heterogeneities.