bluuebunny/crossref_metadata_2025_split huggingface dataset:
Analytical Hindered-Matrix-Fracture Transfer Models for Naturally Fractured Petroleum Reservoirs
Authors: Civan Faruk , Rasmussen Maurice L. 
Published: December 2007

Abstract
The previous studies incorporating the matrix-fracture transfer functions in the naturally fractured reservoir models overlooked the effect of the fracture surface conditions on primary petroleum recovery by pressure depletion and secondary oil recovery by waterflooding and capillary imbibition. This paper presents an improved matrix-fracture transfer model and analytical solutions for rectangular shape matrix blocks in naturally fractured petroleum reservoirs by hindered interface flow between matrix blocks and surrounding fractures. The rectangular shapes are considered to represent the matrix blocks formed by intersecting fractures. The restricted and hindered matrix-fracture interface flow phenomenon is considered in order to account for the effect of the skin due to damaged matrix block surfaces by various processes, including deposition of mineral matter and other debris. The matrix fluid flow equations are formulated for multi-dimensional media, and linearized and solved analytically. The formulation is carried out in dimensionless form, leading to the same dimensionless equations and results based on the analogy between the single and two-phase flow situations involving pressure depletion and capillary-imbibition induced petroleum recovery processes. Then, full scale, and short and long-term analytical solutions are presented and validated by experimental data.
By means of these analytical models, various laboratory experimental data are analyzed, and it is demonstrated that the condition of the matrix block surface is an important factor in determining the rate of fluid flow between matrix blocks and fractures, and the skin effect may reduce the petroleum recovery factor. Comparison with previous simplified models shows that the present model can accurately predict the matrix-fracture interface fluid transfer rate over the full range of the petroleum recovery period, while the previous models can only represent either the early or the late time behavior with limited accuracy. In addition, the effect of the reservoir rock properties on the rate of petroleum recovery by hindered-flow is investigated by means of the hydraulic diffusivity coefficient, determined by correlating the experimental data by means of the new models. This study reveals that there is a strong relationship between the petroleum recovery factor and the diffusion coefficient.
The analytical models developed here can be utilized for rapid and accurate prediction of gas recovery from naturally fractured reservoirs undergoing a pressure depletion or waterflooding process.
Subsea Development of Shallow, Low-Pressure Gas Reservoirs Using High Performance Well Designs
Authors: Burton R. C. , Davis E. R. , Hodge R. M. , Gilbert T. , Stomp R. , Abdelmalek N. , Bailey M. 
Published: December 2007

Abstract
In the summer of 2000, Conoco began a program to develop a series of shallow, low-pressure gas reservoirs in the Indonesian waters of the West Natuna Sea. The project consists of a series of subsea wells linked by pipeline to a central mobile gas processing and compression unit which feeds a sales line to Singapore. Overall project life is 20 years and will require development of 8 small fields with reserves of the order of 1 TSCF gas.
Initial project planning used conventional well designs to deliver rates of the order of 20 MMSCFD/well from a number of gas reservoirs. This type of well productivity required 10 wells to meet Conoco Indonesia's maximum contract supply rate with several wells allocated to each reservoir. To improve project economics, a reduced well count employing high performance completion designs was developed. The high performance completions were designed to provide flow rates of the order of 100 MMSCFD at initial reservoir pressures ranging from 1250 psi to 1900 psi. These flow rates allowed well counts to be reduced to one well per reservoir.
This paper will review Conoco's methodology for design and implementation of the first 4 high performance completions in the West Natuna Sea Gas Project. Well deliverability and initial project results will be discussed.
Integrated Study Workflows for Field Development and Rehabilitation in the Burgos Basin
Authors: Cocker Mark A. , Mendoza Aurelio 
Published: December 2007

Abstract
Since the mid 1990s, when an ambitious program to rejuvenate the Burgos Basin was undertaken, Pemex Exploración y Producción (Pemex) has embraced many of the technologies responsible for increasing gas production in South Texas. These include 3D seismic acquisition and processing, improved drilling and hydraulic fracturing technologies, new logging tools, and comprehensive core studies. However, a critical component to the success of these new technologies is the rigorous application of workflows that integrate the myriad elements required to identify reserves growth opportunities.
Key steps in the workflow involve generating and integrating 3D seismic and well depth structures; seismic attribute tests, depositional architecture maps from logs and core, well logderived rock properties calibrated to routine core and SCAL data, volumetric mapping; comprehensive well history and completion analysis, EUR and drainage area bubble mapping; per-fault block recovery efficiency determination, offset analog comparison, and location selection, risking and ranking.
Two such integrated studies conducted by Pemex with assistance from The Scotia Group (Scotia) identified substantial future reserves potential and demonstrated the effectiveness of this integrated approach. At Corindon-Pandura, in the northwest corner of the Burgos Basin, for example, integration of the depositional systems interpretation, seismic and structural mapping and analysis of EUR bubble clusters revealed an obvious structural component to reservoir performance that is contrary to the depositional architecture. The integrated analysis also indicated that the effective drainage radius of most wells was much smaller (21-115 acres) than the existing 300 acre well spacing. Comparison to contiguous production in Texas confirmed the need for closer well spacing and indicated that improved drilling and completion practices could increase per completion recoveries by 0.5Bcf. Numerous infill and step-out locations were identified at Corindon-Pandura, with reserve growth potential totalling189 Bcf. Drilling to date includes more than 16 successful completions with initial rates averaging 2.8 MMcfd per well.
Similar results were achieved at Mojarrenas-Santa Rosalia where opportunities depended on identifying better primary porosity trends as well as resolving the complex structural influence on reservoir performance. The recent drilling results from the Corindon-Pandura and Mojarrenas-Santa Rosalia field complexes show dramatically the effectiveness of the integrated study workflows being implemented by the Pemex's Reynosa production teams. Characterization of the structural and reservoir complexities of the field areas has enabled Pemex to predict with reasonable certainty the development of target sands. More than 90% of the 72 wells drilled since completion of these studies have been completed and are producing.
Natural Gas-Lift: Theory and Practice
Authors: Betancourt S. , Dahlberg K. , Hovde Ø. , Jalali Y. 
Published: December 2007

Abstract
This paper examines the concept of "natural gas-lift" or production of oil by in situ gas. This process involves the commingled production of an oil reservoir and a contiguous or non-contiguous gas zone in a controlled mode as an alternative to artificial gas-lift. Besides the normal conception of gas-lift as a remedy to high water-cut flow, lift assistance may be required at startup to commission production, and can also be required at low to moderate water-cut, when the wellhead pressure requirements are stringent. The latter is typical of subsea installations and platform installations with high-pressure processing. Contiguous gas-lift is a more complex process, due to the interaction of the oil column with the overriding gas-cap, but can be envisaged more easily than non-contiguous gas-lift which requires the presence of a suitable gas zone or depleted oil zone. We present results of numerical modeling of the contiguous gas-lift process for horizontal wells, for the case of a conceptual reservoir model with characteristics similar to certain North Sea provinces. Results show the applicability of natural gas-lift dependent upon standoff (with respect to the initial gas-oil and water-oil contacts) and target production rate. We also address design considerations for natural gas-lift applications and report the operational experience gained in the Troll field with contiguous or gas-cap gas-lift applications. Finally we examine a gas-lift application of the non-contiguous type.
Acquisition of Directional Survey Data with Adapted Logging Tools
Authors: Rosas R. Rodriguez , Uresti J. A. Niño , Zeegers E. J. , Lips J. P. 
Published: December 2007

Abstract
In the PEMEX Southern Drilling and Producing Region, which includes all land wells drilled in the southeastern states of Mexico, directional drilling has gradually increased to 75% of wells drilled. Producing zones in the region are also deep with difficult targets under high pressure and temperature. These factors have led PEMEX to seek out new technology in an effort to optimize drilling and producing operations.
One of the special projects defined for the year 2001 was to evaluate the application of running a high-accuracy gyroscopic directional survey instrument in tandem with PEMEX logging systems. In the process, the Southern Region engineering group and the PEMEX wireline logging division worked with a local survey company to build a special housing to run the gyro probe on top of several different logging instruments.
This paper describes the development of the tandem gyro-logging combination tool and tests in three wells. System performance is analyzed and comparisons are made between gyro survey results and other survey instrumentation. Conclusions indicate that the success of running two services in one run in the well saves substantial rigtime and eliminates the costs of additional wireline runs. Furthermore, the application of high-accuracy survey information may prove valuable in more accurate wellbore placement and reservoir mapping—leading to enhanced production. In the future, the combination run may also have value in detecting the orientation of imaging logs in both cased and open hole to determine fracture orientation and formation dip angle.
Omani Oil Fields Produced Water: Treatment and Utilization
Authors: Hirayama Akihiko , Maegaito Masaki , Kawaguchi Masato , Ishikawa Akira , Sueyoshi Mark , Al-Bemani Ali Soud , Mushtaque Ahmed , Esechie Humphrey , Al-Mazrui Salim Ali , Al-Haddabi Mansour Hamed , Al-Khanjari Sulaiman Said 
Published: December 2007

Abstract
Joint research between Sultan Qaboos University, Oman, and Petroleum Energy Center, Japan; sought to develop and establish a process whereby the large quantities of produced water from Omani oil fields can be effectively treated and utilized for irrigation. During pilot plant operation, oil contamination ranging from 50-300 ppm, was reduced to below 0.5 ppm. Irrigation with treated water showed no significant detrimental effects on the growth of three different salt tolerant species of plants.
Developments in Completion Technology and Production Methods
Authors: Betancourt S. , Shukla S. , Sun D. , Hsii J. , Yan M. , Arpat B. , Sinha S. , Jalali Y. 
Published: December 2007

AbstractThis paper contains a condensed description of recent developments in completion technology and relates how these technologies have enabled novel production methods. Field applications reveal the geological, reservoir and surface characteristics that favor the application of these methods.
Depositional Environment Interpretation Using NMR and Core Data
Authors: Syngaevsky Pavel E. 
Published: December 2007

Abstract
This study is based on data from Gulf-of-Mexico (three wells) and West Siberia, Russia (two wells). We find a clear correlation between the NMR signal and depositional environments that also were identified on conventional log diagrams and in cores. Key sediments associated with the regressive bar and coastal fluvial sand sequences (distributary mouth bar, distal bar, delta-front, and pro-delta facies) were defined by predominant type and distribution of porosity and recognized on NMR diagrams. Corresponding distribution of total and effective porosity, permeability and amount of capillary bound water characterized the major depositional environments.
Seven rock types (lithofacies) were defined using statistical analysis of porosity/permeability laboratory data, SEM and thin-section description and mercury injection results; four of them were clearly correlated to various shapes of NMR response. The mixed type of porosity (associated with kaolinite cement) and interbeds with carbonate concretions (hardstreaks) were not recognized. The dissolution of feldspar grains in distal mouth bar facies results in significant enhancing effective porosity and permeability. An abnormally height porosity values (higher than 26 pu.) were formed as the result of feldspar and rock fragments total dissolution. Partial dissolution produces a micro-porosity that contains bound water. Results from both processes were recognized on NMR T2 distribution diagram. A dual porosity system was also identified on porosity-permeability cross-plot as two parallel areas.
NMR signals characterize the spectral porosity distribution and therefore could be used for various facies differentiation.
It provides a unique information on diagenetic alteration especially about total or partial grains dissolution. Best results on quantitative interpretation could be achieved by combining analysis of core data (SEM) and NMR logs.
Field Application of Near-Balanced Drilling Using Aqueous Foams in Western Venezuela
Authors: Rojas Y. , Vieira P. , Borrell M. , Blanco J. , Ford M. , Nieto L. , López G. , Atencio B. 
Published: December 2007

Abstract
This paper presents operational results of the pilot test under near balanced conditions of a new foam drilling fluid developed by PDVSA-Intevep in an inclined well drilled in La Paz Field in Western Venezuela. The target formations were a fractured, depleted limestone formations of low pressure, and the reservoir contains highly fractured and hard rocks, known for deferred oil production due to flushing by lost circulation. Similar wells drilled with aerated fluids in the vicinity have shown very low rates of penetration, short bit lives, and instability drilling fluid in presence of contaminants such as salts and crude oil. Results indicated that the foam formulation provided a high stability in presence of crude oil and cement contaminations, and an excellent cleaning capacity in a 12-1/4" hole wherein minimum annular velocities of 45 ft/min were obtained. The physico-chemical properties of the foam allowed regenerating the fluid 76 times with minimal amount of additives. Besides, the average rate of penetration was greatly increased compared to wellbores drilled conventionally and the bit used lasted much longer than in a conventional well in the same reservoir. Finally, this formulation specially developed to withstand high volumes of contaminants proved to be an excellent drilling fluid for near or underbalanced operations with adequate characteristics and very good performance.
Considerations Given to Land Rig Design for Versatility of Operations
Authors: Isinger Ron 
Published: December 2007

Abstract
This paper discusses factors that were considered in the design of the first generation Super Single™ rig. The initial design concept was driven by certain drilling requirements for a slant drilling operation of PanCanadian Petroleum. The discussion also includes examples of the rig's application, operating data and results and safety benefits achieved from the new rig design.
PanCanadian first applied the Super Single rig to a slant hole drilling under Lake Newell in southern Alberta. This application and subsequent projects, which represent a total of more than 5,000 wells drilled, have proven that the Super Single rig is more efficient and safer than conventional double, telescoping double and single rigs in the overall completion of a drilling well.
Multistring Casing Design for Deepwater and Ultradeep HP/HT Wells: A New Approach
Authors: Samuel G. Robello , Gonzales Adolfo , Ellis Scot , Kalil Issa 
Published: December 2007

Abstract
Drilling operations in deep water and ultra-deep water are increasing around the world. The development of these substantial prospects is very challenging and requires integration of knowledge with prudent designs at different stages of the well development. However the cost premium imposed by deep water and ultra deep wells are higher and many of the discoveries are marginal in terms of the commercial viability. With the increase of developing and operating costs, there is a growing need to reduce the cost of drilling and other allied operations. The casing program constitute a significant portion of the well cost and this calls for an alternate approach to the casing design criterion particularly relevant to high temperature and high pressures are encountered in ultra deep wells. Challenges associated with extreme depth, pressures and temperatures where annular fluid expansion is a problem translate to additional problems in casing design. It is therefore required to align design objectives closer to the changed requirements, which necessitates changes in traditional casing design methods. The design implemented should be without sacrificing the safety and integrity of the well.
This paper presents a study on the new approach and the alterations proposed to the casing design to adapt to the new criterion for the deep water and ultra deep high-temperature high-pressure wells. This paper will examine some of these proposed changes, while asserting that it is necessary to integrate this new approach, so that cost effective solutions can be derived as a result. This new design encapsulating annular fluid expansion and pressure provides a simple, practical way to view the severity of the composite well system during the course of drilling as well as the production phase of the well. The practical usefulness of the theory, backed by the fundamental analysis is demonstrated with three numerical examples.
A New TAML Level 3 Multilateral System Improves Capabilities and Operational Efficiencies
Authors: Fipke Steven , Oberkircher Jim 
Published: December 2007

Abstract
In recent years there has been a dramatic increase in the pace of the evolution of multilateral systems. Many systems with new features and improved functionality have been introduced which have enhanced the success and growth of multilateral technology. The MACH-3™ system is among the latest of these offerings. This innovative hybrid system is an example of RMLS™ technology that has been re-designed to provide a simpler and faster method of completing TAML Level 3 multilateral junctions. This system will greatly reduce the amount of rig time required for multilateral junction construction by simplifying the installation process and minimizing the number of trips to complete. It also provides increased functionality with large diameter, selective re-entry access to either the lateral or main well bore. Primarily designed for heavy oil applications where the cost of installation is a major issue, the system has potentially far reaching applications in this and other markets.
The paper describes the mechanical and operational principles of the system in its potential applications. The basic functionality of the MACH-3™ system will be analyzed, and some simple guidelines and limitations will be put forward for the selection of a Level 3 multilateral system. These guidelines are based on some of the lessons learned from multilateral experience in Canada, Venezuela and the U.S.A.
The Blowout at UPRI Search Klua d-27-J/94-J-8
Authors: Grace R. D. , Bueckert J. D. , Miller M. 
Published: December 2007

Abstract
In December 1999, UPRI and Search Energy combined their resources to drill an exploration well south and west of Fort Nelson, British Colombia. An unusual chain of events combined to result in loss of control and a blowout. Located in an environmentally sensitive area, containing the blowout was a most important priority and a most difficult challenge. The very high flow rate, hydrogen sulfide content, large volume of water and freezing temperatures made work at the well slow and difficult. This paper chronicles the unusual chain of events that preceded the blowout and the equally unusual approach to recovery. The lessons learned at the Klua blowout will be of benefit to the entire industry worldwide.
North Sea Coring Record Attained by Step Change Application Modeling
Authors: Norrie A. G. , Akram S. , Niznik M. R. 
Published: December 2007

Abstract
A North Sea coring record was set by Conoco UK Ltd (CUKL) and service provider Baker Hughes INTEQ (BHI) on 20 January 2001. A 179-ft core was cut and recovered in 6" hole from the Rotliegendes formation in the Southern North Sea.
In-depth operational planning, which included offset core viewing by a multi-discipline well team was undertaken in an effort to identify potential coring hazards. Physical testing of offset cores, rock strength data, and other relevant data sets were used to model the length of core that could be safely cut.
The coring operation was executed with the selected coring assembly and 179 ft of high quality core was recovered. Subsequent testing and analysis was performed on the core, which satisfied all evaluation requirements of the sub surface team. CUKL and BHI have successfully applied these planning techniques on a number of other wells resulting in significant improvements in coring efficiency, recovery and core quality.
Pressured Drilling Riser Design for Ultra-Deepwater
Authors: Zhang Jane , Magne Eric , Morrison Denby , Efthymiou Mike , Leach Colin , Lo King H. 
Published: December 2007

Abstract
This paper focuses on the design considerations of a pressured drilling riser that can be used with a surface BOP in deepwater. One key element to the development and reliable use of surface BOP drilling is this (riser) link between the seabed and the drilling rig.
The pressured drilling riser, unlike a conventional marine drilling riser, is not designed to cover all situations and applications. On the contrary, it is a purpose-built riser designed to suit the requirements of specific drilling application.
This paper outlines the general design process of the surface BOP riser. Discussion of key design issues that are sensitive to ultradeep-deepwater application are included.
The technical aspects of using (disposable) standard casing with threaded connector for the drilling riser are discussed, with a particular emphasis on the connector fatigue-testing program to quantify the stress concentration factor for fatigue design.
Emerging composite material offers some alternatives to the steel riser when drilling in ultra-deep water. Design issues related to the high-pressure composite drilling riser are briefly discussed.