bluuebunny/crossref_metadata_2025_split huggingface dataset:
Optimized Horizontal Well Placement in the Otter Field, North Sea using New Formation Imaging While Drilling Technology
Authors: Tribe Ian , Holm Gordon , Harker Stuart , Longis Christian , Milne Keith , Stromberg Simon , Greiss Rita , Webb Kate 
Published: December 2007

AbstractThis paper demonstrates how new Logging While Drilling (LWD) and Measurement While Drilling (MWD) tools were used to optimise placement of 3 sub-horizontal wells in a faulted, sand-shale oil bearing Brent Group reservoir known as the Otter Field, Northern North Sea, United Kingdom. As the target reservoir layer is only 8m thick and sub-seismic faulting and subtle changes in dip occur in the field, geosteering of the well paths was anticipated prior to commencing drilling. To aid with geological steering of the wells a new LWD tool was run: the azimuthal GR-resistivity device and this provided high-resolution borehole images of formation geology (eg. formation layering and dip, fault location and orientation). Using state-of-the-art mud-pulse MWD telemetry and the world-wide web, the images and other LWD data (eg. porosity) were made available, real-time, to both the onshore and offshore drilling team. Detailed geological cross sections constructed in real-time from the image logs aided steering the wells to the optimum geological locations. One of the three production wells [well 210/15a-T2 (P1)] is used to demonstrate how the imaging while drilling, viewed real-time via the web, was applied. This case study highlights the benefits the technology brought to the drilling operation and field development in terms of efficiency improvements in geological analysis and well steering decision making and maximized oil production through optimum well placement.
Twister Supersonic Gas Conditioning for Unmanned Platforms and Subsea Gas Processing
Authors: Brouwer J. M. , Epsom H. D. 
Published: December 2007

Abstract
Twister™ is a revolutionary gas conditioning technology which has been under development for natural gas applications since 1997. Condensation and separation at supersonic velocity is the key to some unique benefits. An extremely short residence time prevents hydrate problems, eliminating chemicals and associated regeneration systems. The simplicity and reliability of a static device, with no rotating parts and operating without chemicals, ensures a simple facility with a high availability, suitable for unmanned operation.
Full scale test units have been operational since 1998 at five gas plants in the Netherlands, Nigeria and Norway, with varying gas compositions and operating conditions. Test results have been used to improve and validate sophisticated Computational Fluid Dynamic (CFD) models of the complex combination of aerodynamics, thermodynamics and fluid-dynamics. These CFD models have been paramount in improving Twister performance.
Although Twister is a mature technology, Twister BV are developing a second generation Twister design promising a step change performance improvement and reduced pressure drop. Field testing is scheduled for early 2004 with market launch later that year.
The first commercial Twister application will start-up in the 4th Quarter of 2003. Twister has been selected for the dehydration process of a large, offshore gas development in Malaysia. The Twister system design will be described.
Its simplicity makes Twister a key enabling technology for subsea gas processing. The results of a joint industry feasibility study will be reported.
Oil and Gas Recovery Behaviour in the UKCS Basins
Authors: Toole S. T. , Grist D. M. 
Published: December 2007

Abstract
Company management, industry analysts and governments like to have measures of portfolio or national resource performance. Recovery factors are one such means of assessing relative performance. The UK DTI's large database has been employed to assess the distribution of recovery factors with basin parameters. Assessed over time, ultimate recovery factors indicate how expectations have changed for the UK North Sea fields and how new technology and cost reduction have broadly influenced exploitation. Recovery factors also seem to relate to geological facies. Forward prediction of overall growth in recovery factors is of concern for gauging the security of local and world supply. Of course there are caveats or limitations and these are discussed.
New Tools and Fluid Technology Redefine the Application Envelope for Horizontal Openhole Gravel-packing Into a Mainstay Deepwater Completion Method
Authors: Ali Syed , Grigsby Tommy , Vitthal Sanjay 
Published: December 2007

Abstract
Synergy between the horizontal drilling and openhole completion disciplines is required to deliver a reliable high-rate well completion in soft rock formations. This gap has finally been bridged, and the resulting success has allowed it to be considered as a mainstay completion technique in deepwater developments in Brazil. It has shown the same potential for upcoming deepwater developments in West Africa. The technology has also been an enabler for heavy oil developments (API gravity &lt;20 deg, and &gt; 0.934) in Brazil and in the North Sea that otherwise would have been uneconomical.
This paper will address where we started, the evolution of technology, and the lessons learned that are being applied to increase the application envelope and the reliability of this completion method. The review will cover advances in openhole drilling techniques that eliminate hole tortuosity, gravel-pack fluids that can reduce rig time and enhance well productivity, and improvements in downhole tools that have capability to reduce risk while reducing completion cycle time. The review will also examine a possible replacement technology.
The successes already achieved in light of the recent technological advances will be presented in case histories that will verify the reliability that can now be expected.
An Innovative Thermal Production Scheme for Mobile Heavy Oil Reservoirs with Bottom Aquifer
Authors: Rodriguez J. R. , Darche G. , Espinasse J. 
Published: December 2007

Abstract
This paper describes an innovative thermal production scheme, named "Horizontal Alternate Steam Drive" (HASD). This process has been designed to improve the recovery of mobile heavy oils in presence of bottom aquifers, where natural depletion is inefficient because of strong water coning from the aquifer.
HASD is a repetitive pattern using equi-depth horizontal drains acting alternatively as producers and steam injectors: the main recovery process is horizontal steam flooding between successive wells and is more efficient than classical cyclic steam injection.
After the description of the process itself, we will illustrate the performances of HASD using simulation results on simple 2D homogeneous models. We will finally show, using 3D simulations, that HASD increases the recovery in presence of moderately connected aquifers, as compared to natural depletion, and could even improve the performances obtained by more standard thermal processes such as SAGD (Steam Assisted Gravity Drainage).
Effect of Rate and Viscosity on Gas Mobility during Solution-Gas Drive in Heavy Oils
Authors: Talabi O. , Pooladi-Darvish M. , Okazawa T. 
Published: December 2007

Abstract
Some heavy oil reservoirs under primary production have shown higher recovery and production rates than expected. Many studies have shown that gas mobility in these reservoirs is low contributing to improved oil displacement and also that gas mobility may depend not only on gas saturation but also on depletion rate and oil viscosity. Despite the observed effect of oil viscosity and depletion rate on gas mobility, it is not yet clear to what extent these factors affect relative permeability and critical gas saturation.
In this study, we have conducted depletion experiments in a linear unconsolidated sand-pack. Three oils were used, with oil viscosities that varied by a factor of 30. The experiments were conducted at two different depletion rates for each of the oils. Experimental results show that as oil viscosity or depletion rate increases, critical gas saturation increases, gas mobility decreases and oil displacement becomes more effective. Critical gas saturation for all the runs was in the range of 0.2 – 5±1%. Furthermore, it was found that relative permeability to gas decreased as withdrawal rate or oil viscosity increased. The effects of oil viscosity and withdrawal rate were combined in the form of a depletion index, such that oil recovery increased as the depletion index increased.
Streamline-Based Dual Porosity Simulation of Fractured Reservoirs
Authors: Di Donato Ginevra , Huang Wenfen , Blunt Martin 
Published: December 2007

Abstract
We present a streamline-based dual porosity simulator to model waterflooding in fractured reservoirs. Conceptually the reservoir is composed of a flowing fraction, representing the fracture network and high permeability matrix, in communication with relatively stagnant regions. Streamlines capture movement through the flowing fraction while the transfer of fluid from flowing to stagnant regions is modeled as a source/sink term in the one-dimensional transport equation along each streamline.
We discuss different possible forms of the transfer function to represent counter-current imbibition. We implement three forms of the transfer function: the conventional steady-state model and two linear transfer functions that match experimental measurements on cores. An appropriate linear transfer function can be found that gives results similar to the conventional model, matches experiment and gives run times similar to standard single porosity simulation.
We compare the results and run times of the streamline-based approach with conventional dual porosity grid-based simulation. Using an example North Sea dataset for a highly heterogeneous reservoir, we show that streamline simulation gives similar answers to grid-based methods when using the same transfer function, but is at least one to two orders of magnitude faster for models with 100,000 to 1,000,000 grid blocks.
Black Oil Streamline Simulator with Capillary Effects
Authors: Berenblyum Roman A. , Shapiro Alexander A. , Jessen Kristian , Stenby Erling H. , Orr Franklin M. 
Published: December 2007

Abstract
A streamline simulation with capillary and gravity is presented. The black oil streamline simulator [3DSL 0.25 by R.P. Batycky, SUPRI-C group, Department of Petroleum Engineering, Stanford University, 1997] was modified to incorporate capillary effects.
The new simulator has been applied to several simulation cases. We discuss the influence of different factors that may impact performance prediction of water floods. The capillary forces are demonstrated to stabilize the displacement front and increase oil production even in rather viscous-dominated cases.
The new approach can provide a fast and a reliable tool for the simulation of water flooding in low permeable and heterogeneous oil reservoirs as well as for reservoir screening and upscaling studies.
Zulu Pipeline Debottlenecking
Authors: Aritonang Leonardo , Lucich Michael A. , Kurz John E. , Haryanto Kun , Suyanto Ato , Anwar Chairil 
Published: December 2007

Abstract
AVSA and Zulu production areas, located in the NW corner of BP's Offshore Northwest Java, ONWJ, production sharing contract, (PSC), posed a significant challenge for its operator. Production rates had declined significantly, operating costs were creeping up and system reliability was at an all time low. An unreliable compressor pushed gas down an unstable 44.5-mile 20-inch three-phase pipeline from the Zulu Flow station to the PCP central gas-gathering center (Figure-2). At the same time, the AVSA Flow station, located approximately 16 miles to the north, with marginal production, high pour point crude and stranded gas had been shut-in for nearly 2 years due to low export pipeline temperatures associated with low flow rates. A troubleshooting team was hard at work trying to improve Zulu compressor reliability while a team of facilities engineers was trying to figure out how to take water out of the system to reduce pipeline backpressure and mitigate slugging problems. In an attempt to increase production, reservoir and production engineers were testing the economics of ESP recompletion in both fields.
The Asset Manager, frustrated by the lack of progress at Zulu, and under pressure to increase production and improve compressor reliability felt that water removal would help elevate slugging, stabilize pipeline pressure and reduce compression headaches at Zulu. He organized a team to consider water removal options.
What resulted was a not so obvious flow reconfiguration solution that eliminated a major operational defect. The operation was simplified, facilities reliability improved, production increased and lifting costs fell and management could turn its attention elsewhere.
This paper presents a production system operability problem on a very mature offshore oil and gas producing asset, the simple but effective defect-elimination-solution and the resulting benefits.
Integrated Characterization of the Thin-Bedded 8 Reservoir, Green Canyon 18, Gulf of Mexico
Authors: Aniekwena Anthony U. , McVay Duane A. , Ahr Wayne M. , Watkins Joel S. 
Published: December 2007

Abstract
The thin-bedded, channelized-turbidite 8 reservoir of the Green Canyon 18 field (GC-18) had previously been difficult to describe owing to its complex architecture and limitations in seismic data resolution. The reservoir has high rock compressibility. Its complex geology had, before this study, prevented the delineation of its hydrocarbon accumulation and determination of the different resource volumes.
An integrated approach has been used to develop a geologically consistent model of the reservoir. Seismic interpretation and attribute extraction provided the reservoir geometry and stratigraphy, which show the preeminent role of salt tectonics in the shaping of the reservoir before and after deposition. Geostatistical methods were used to construct gross and net thickness maps and to infer lateral variations in the quality of the 8 sand. Lithofacies description from cores showed 3 distinct facies - channel, levee, and overbank deposits - that were sufficient to describe the reservoir. Fine-scale heterogeneity in each zone was determined from core and log lithological descriptions. Truncated Gaussian sequential simulation was performed to distribute facies and reservoir properties throughout the reservoir volume.
The resulting geological model was used to construct a dynamic flow model that matched historical production and pressure data. This work shows the efficiency of the integrated approach in describing complex reservoirs where the internal variability is a major control of flow efficiency. This approach is especially valuable in reservoirs like the GC-18 8 reservoir where the well information is scarce or not uniformly distributed.
Wellsite Information Transfer Standard Markup Language, WITSML, an Update
Authors: Kirkman M. A. , Symmonds M. E. , Harbinson S. W. , Shields J. A. , Will M. , Doniger A. 
Published: December 2007

Abstract
E&P companies are now putting more focus on collaborative asset teamwork to speed and improve decision-making involved with developing oil and gas fields. To facilitate such collaboration, E&P companies are adopting shared, integrated, IT technology to enable multi-disciplinary teams to engage in improved workflow processes across all phases of the oil field life cycle. Much of the data needed to feed these workflow processes can be shared between Service Companies and E&P companies during the planning and execution phases of the wellbore construction process. The "right time" seamless flow of this data between operators and service companies will speed and enhance decision-making.
There have been a number of solutions tried over the past 20+ years, some more successful than others. The WITSML initiative was started in 2000 to update the existing methods for the 21st century and incorporate the lessons learned from previous initiatives. It is sponsored by both E&P operators and oilfield service companies, aimed at providing an industrywide solution for transfer of information between service companies and E&P companies.
This paper will provide a brief review of the WITSML initiative, its original charter and development effort. It will then explore the current status of development for the standard and its API, discuss the current commercial development and the strategy, which aligns the initiative with POSC for the support and enhancement of WITSML. In addition, the paper will briefly discuss future potential areas of benefit for E&P companies, such as WITSML use in the Production Phase of the E&P life cycle.
Simulated Expert Interpretation of Regional Data to Predict Drilling Risk
Authors: Balch R. S. , Weiss W. W. , Ruan T. , Weber S. 
Published: December 2007

Abstract
Incomplete or sparse information contributes to high levels of risk for oil exploration and development. To more accurately and consistently predict drilling risk, a degree of automation of data analysis may be helpful. "expert systems" developed and used in several disciplines and industries, have demonstrated beneficial results in modeling the decision making process of human experts. A state-of-the-art "expert" exploration tool using computerized multidisciplinary databases, expert developed "rules", and regional data maps -generated using artificial neural networks, has been developed.
The system employs a web interface for users to select prospect(s) of interest and to allow data review or addition, and includes security to maintain the sanctity of proprietary information. Two types of rules are applied to the data. Heuristic rules are generated directly from engineering, geophysical and geological databases. Expert rules are developed through interviews with successful prospectors. Rules are applied in four categories: Regional Indications, Trap Assessment, Formation Assessment, and Oil Price. Some users may elect to not factor in certain aspects, or to use their own values.
Each of the sub systems assigns a numerical score based on the answers to individual "expert" questions. Results are then combined to form an overall risk assessment associated with the selected prospect(s). These scores can be derived from "crisp" mathematical computations, "fuzzy" analysis, or a combination of the two.
This expert system can help companies of all sizes, to more efficiently evaluate prospect quality, and thus more rapidly eliminate poor prospects and generate new production from favorable prospects. The initial system has been initially tuned for the Brushy Canyon formation, Delaware basin, New Mexico.
Practical Approach in Modeling Naturally Fractured Reservoir: A Field Case Study
Authors: Bahar Asnul , Ates Harun , Al-Deeb Maged H. , Salem Salem E. , Badaam Hussein , Kelkar Mohan 
Published: December 2007

AbstractThis paper presents a practical approach in modeling a naturally fractured reservoir. The approach was used for a field study of a giant carbonate reservoir in the Middle East. The method is shown to be practical and comprehensive and yet has produced good results. It consists of a fully integrated effort from geological, geophysical and engineering disciplines. The overall goal of the study is to develop a representative reservoir model to form the basis for reservoir management and long-term development planning.The approach consists of the following procedures: Generation of multiple realizations of matrix property using geostatistical techniques. The standard cosimulation procedure was implemented to ensure the consistency among reservoir properties, namely rock type, porosity and permeability.Generation of multiple realizations of 3D fracture property by reconciling seismic, well logs and dynamic data. These were obtained from curvature analysis and seismic facies map validated by borehole image and dynamic data. The fracture network was described in the reservoir as lineaments (fracture swarms) showing two major fracture trends.Calibration of the model permeability with well test-derived permeability considering fracture distribution. A newly developed technique was implemented to ensure that the fine scale model (i.e., geological model) honors well test as well as production data before it was subjected to the flow simulation. The technique also generates permeability anisotropy to account for fracture orientations.Ranking of multiple realizations using streamline simulation to select three representative realizations (low, medium and high models).Upscaling of reservoir properties, including vertical upscaling level optimization using streamline simulation.History matching and future performance prediction of the three selected realizations as a single media model. The use of single media model was based on the observation of relatively high matrix permeability in the major producing zone. However, for comparison purposes, a dual media model was also developed.Uncertainty analysis of the future dynamic performance using a probabilistic approach.The procedure described above has been implemented successfully in a field study. The use of a calibration process in the geological model reduces the number of parameters that need to be adjusted during history matching. Consequently, history matching may concentrate on the uncertainty in parameters that have not been specifically accounted for in the geological modeling stage, such as relative permeability and aquifer size/strength.
Will Wireline Formation Tests Replace Well Tests?
Authors: Whittle T. M. , Lee J. , Gringarten A. C. 
Published: December 2007

AbstractWell testing in exploration and appraisal wells has become increasingly unpopular. Reasons include costs, safety and environmental impact. Well testing has also become rare in production wells because of the potential revenue loss during build-ups. Whether suitable alternatives can be found for sampling and reservoir parameter estimation is the subject of regular debate. Alternatives are wireline formation tests in exploration and appraisal, and continuous recording with permanent pressure gauge in production wells.The quality of pressure and rate transients measured during wireline formation tests has improved greatly in recent years. The transients obey the same laws of physics as those measured during a well test and can theoretically be interpreted in the same way. The scale of the measurements, however, is very different. The challenge is to understand what the wireline formation test interpretation results mean and how they can be upscaled to the information provided by a well test.The paper discusses these key issues with examples that illustrate the quality of the data and the analysis process. The interpretation methods are essentially the same as those used in well test analysis with the addition of the formation rate analysis plot, which is particularly useful in high permeability formations where other methods are limited by pressure gauge resolution.