bluuebunny/crossref_metadata_2025_split huggingface dataset:
Design and Implementation of a Grass-Roots CO2 Project for the Bennett Ranch Unit
Authors: Hsu C. F. , Fitzgerald M. A. , Musallam S. C. , McCray T. L. , Purvis W. D. 
Published: December 2007

Abstract
Large-scale CO2 projects, like those implemented more than a decade ago in the Wasson Field, are not as attractive today because of large capital investments up-front and lower and uncertain oil prices. However, building upon our experience in large-scale floods, as well as recent improvements in the reservoir characterization and simulation technology, a grass-roots CO2 project can still be made attractive, in today's environment, by high-grading the reservoir resources, staging the development, and re-injecting the produced gas without facilitating a large gas processing plant. The paper contrasts the characteristics of the Bennett Ranch C02 project, a CO2 flood designed today, with traits of CO2 floods of yesteryear. The paper also highlights the innovative efforts in reducing and delaying the capital expenditures for wells and facilities, resulting in a less than 1 MM$ capital investment prior to the CO2 injection. Due to small flood patterns, significant production responses have been observed after only 3 months of CO2 injection.
Lost Soldier Tensleep CO2 Tertiary Project, Performance Case History; Bairoil, Wyoming
Authors: Brokmeyer R. J. , Borling D. C. , Pierson W. T. 
Published: December 2007

Abstract
The Lost Soldier Tensleep field tertiary performance has a noteworthy case history that demonstrates how an incremental 13% of original oil in place will be recovered from this sandstone reservoir using carbon dioxide. Located in south central Wyoming, the Lost Soldier Tensleep has been under carbon dioxide (C02) injection since 1989. From 1989 through 1995, a 61% hydrocarbon pore volume (HCPV) slug of C02 was injected into the reservoir to recover an incremental 13.6 million barrels of tertiary oil. Prior to C02 injection, the reservoir was producing 2,500 bopd at a 97% watercut. Within one year, oil production exceeded 10,000 bopd and is currently 6,000 bopd.
Since its start-up in 1989 with 47 producers and 40 injectors, the subject flood has used a water-altemating-gas (WAG) method and line drive pattern to process approximately 840 acres of reservoir. Illustrations of actual WAG injection cycles and resultant offset production response are included in this case history. The Lost Soldier flood has been so successful that one producing well had an incremental rate of 1700 bopd, carrying the unique distinction of having the highest peak incremental C02 response that the authors could find documented in U.S. literature.
Information contained in this paper provides observations and conclusions about field performance optimization as well as reservoir management philosophy. Several actions were completed during the early to mid-1990's to maximize recovery and profitability. These included maintaining miscible reservoir pressure, increasing natural gas liquid recovery, converting to sour reinjection, and exploiting downdip oil potential.
Pulsed-Neutron Capture Logging in Reservoir Management: Three Permian Basin Examples
Authors: Haynes F. M. 
Published: December 2007

Abstract
Pulsed-neutron capture logs (PNC) have been applied to address specific reservoir management issues in three mature Permian Basin fields (Cordona Lake, Cornell, and East Vealmoor). When combined with existing well data and a knowledge of formation fluid compositions, single runs with PNC logs have provided valuable reservoir surveillance data in secondary and tertiary recovery reservoirs. The logs have led directly to increased production, more cost effective workovers, and an improved understanding of fluid contact movement and injection breakthrough.
Areal Pattern Distribution of Remaining Oil Saturation in a Mature West Texas Waterflood – A Case History
Authors: Sharma Arun K. , Anil Kumar 
Published: December 2007

Abstract
A novel material balance technique presented by Kumar et al1 has been applied to estimate areal pattern distribution of remaining oil saturation, ROS, in a mature West Texas San Andres carbonate waterflood which is a potential candidate for the implementation of an improved oil recovery (IOR) project. This material balance accounts for two major dynamic unknowns: (1) loss of injected water vertically into non-target zones, and areally to adjacent patterns, and (2) progressive gas fill-up that begins with the start of water injection and may continue for several years before reaching the maximum fill-up.
The calculation procedure discussed here can be easily converted to a spreadsheet program and requires only readily available field production and injection data for oil, water and gas. The results indicate that 50 of the 103 patterns in the unit have been depleted to waterflood residual oil saturation, Sorw, and 33 patterns comprising 42% of the pore volume have relatively high ROS (&gt;45%) even after 18 years of injection. A normal distribution in ROS is obtained in this unit with ROS ranging from a high of 67% to a low of 21%. This information is highly desirable for waterflood surveillance, monitoring, and in planning for an IOR project.
Multi-Lateral Horizontal Wells Optimizing a 5-Spot Waterflood
Authors: Hall S. D. 
Published: December 2007

Abstract
Interest in horizontal drilling has increased over the last six years. Most horizontal drilling has been in primary recovery operations to intersect fractures. Applying horizontal technology in a multi-layered carbonate waterflood has different challenges. For example, how can areal and vertical sweep efficiencies be improved? Short radius multi-lateral wells meet that challenge. Review of the design, application, and results shows multi-lateral wells superior to vertical and single lateral wells.
Comprehensive Evaluation of Horizontal Wells with Transverse Hydraulic Fractures in a Layered Multi-phase Reservoir
Authors: ElRafie E. A. , Wattenbarger R. A. 
Published: December 2007

Abstract
The objective of this work was to investigate the viability of converting existing conventional vertical wells to horizontal wells with multiple transverse fractures in targeted reservoirs. These reservoirs can be characterized as two thin, low permeability layers with no crossflow between them. The productivity of these reservoirs was very limited when producing by conventional vertical wells.
Reservoir simulation was used to evaluate various combinations of transverse fractures in horizontal wells. These results were compared with simulation results for conventional vertical wells, with and without vertical fractures. Only infinite conductivity fractures were considered. Early transient behavior as well as pseudosteady-state behavior were simulated.
The results show that horizontal wells with transverse fractures appear to make production of the targeted reservoirs economically feasible.
It has been shown that the productivity index of horizontal wells with transverse fractures is mainly affected by the distance between the outermost fractures and not by the number of fractures nor the spacing between them. Between fractures perforations has been shown to have negligible effects on increasing the productivity of horizontal wells with transverse fractures in these reservoirs. Decline type curves are presented, for horizontal wells with transverse fractures, for future performance prediction and reserves estimates.
An Engineer's Guide to Legal and Regulatory Matters for Horizontal Wells in Texas
Authors: Judah J. S. 
Published: December 2007

ABSTRACT
This paper will provide a guide for engineers and operators to the legal issues, Railroad Commission's regulations and practices governing horizontal wells in Texas, with particular emphasis on their application in the Permian Basin. Horizontal drilling is standard in the Austin Chalk trend and its application is spreading as the technology becomes cheaper and gains acceptance. The paper will cover drilling issues, completions, allowables, secondary recovery, and land and legal considerations. Its purpose is to provide a practical map for Permian Basin engineers through the legal and regulatory minefield.
Characterization of the Naturally Fractured Spraberry Trend Shaly Sands Based on Core and Log Data
Authors: Banik Ashish K. , Schechter David S. 
Published: December 2007

Abstract
In this paper, the naturally fractured Spraberry Trend Area reservoirs have been characterized with emphasis on identification of oil-bearing silt and sands based on core-log correlation. Integration of extensive geological, geophysical and petrophysical data into a modem shaly-sand log interpretation model has been made in this study to characterize the Spraberry Trend properly. Quantitative cut-off criteria based on core-log correlation was developed which allows log based identification of thin oil-bearing intervals suitable for hydraulic fracture treatment. The Archie parameters (a, m and n) have been derived from core data to improve log-derived water saturation. Corederived porosity and water saturation have been compared with log-derived values for the purpose of quantitative identification of oil-bearing intervals. The results from this investigation provide recommendations for logging suites that will allow a better description of thin pay sands which characterize the Spraberry Trend throughout the Midland Basin. The methodology developed may be used primarily to understand the areal extent and pinch-off of productive intervals and the water saturation within the pay intervals. We believe this technique to be one of the ingredients required to understand the controlling parameter of fracture intensity within the pay zones (i.e. bed thickness, curvature etc).
Use of Production and Well Test Data with Predictive History Matching to Improve Reservoir Characterization for CO2 Flooding at the South Cowden Unit
Authors: Harpole K. J. , Gerard M. G. , Snow S. C. , Caldwell C. D. 
Published: December 2007

Abstract
The South Cowden Unit was selected for one of three mid-term field demonstration projects being conducted under the DOE Class II Oil Program for shallow-shelf carbonate reservoirs. The South Cowden project is designed to demonstrate the technical and economic viability of using horizontal CO2 injection wells and centralization of surface facilities to optimize CO2 project economics. If successful, this approach will help to improve the economic viability and application of CO2 flooding for many smaller fields which might otherwise soon face abandonment.
Successful design and implementation of the project requires a focused, cost-effective reservoir characterization effort to identify those reservoir characteristics and field areas best suited to application of this technology. Integration of production and well test data with geologic reservoir description information was necessary to develop a sufficient understanding of the permeability distribution at South Cowden. A predictive history matching approach was used in modeling historical field performance to further refine the reservoir description.
Fracture Monitoring Using "Low Cost" Passive Seismic
Authors: Taylor A. R. , Brown K. , Hinterlong G. , Watts G. , Zeitmann T. , Justice J. , Woerpel C. 
Published: December 2007

Abstract
Passive seismic measurements were taken before, during, and after a fracture stimulation treatment to monitor the fracture growth and optimize future fracture treatments. The seismic events created by the fracture treatment showed an asymmetrical east-west trend during the treatment, with wide variations in the locations of events. The passive seismic measurements support the previous belief that the fracture orientation for the field is east-west. However, the recorded events showed more complexity to the fracturing process than had been anticipated. The events showed a southwest trend toward a producing well along with the widely scattered events to the east. Neither, the 3D fracture simulator, pressure transient analysis, nor production injection data supports the very large fracture geometry of the passive seismic events.
Fracture lengths and heights from the passive seismic events varied along with the directions. The length of the wing to the southwest showed seismic events over 1200 feet from the well, while the east wing events only reached about 700 feet. The different wings also showed a large variation in the height of events. Although the treatment interval was 4820-4910 feet, seismic events occurred from 4550-4900 feet for the southwest wing and 4600-5008 feet for the east wing. The shorter length to the east is believed to be due to the well being offset to the east, by another injection well. The higher pore pressure, from the water injection, caused the fracture pressure to increase, thereby changing the direction of growth of the fracture.
The passive seismic results show that fully modeling the fracture process will need to incorporate a simulator that allows varying fracture parameters aerially as well as vertically. The 3D model, of the initial 1966 fracture treatment, showed a propped fracture length of 139 feet, with a propped area of 29,000 square feet. The prefracture falloff, which followed running a liner and a cement squeeze, showed an area of 15,000 square feet. The second 1995 treatment model results gave a length of 150 feet and an area of 26,000 square feet. The values for the last job match very closely the pressure transient results following the treatment, of 24,000 square feet, showing that the current model can predict fracture results adequately for most evaluation purposes. However, for nonuniform pressure gradients a more detailed areal model will be needed.
Digital Data Acquisition for Tracer Quality Control
Authors: McLaughlin James S. 
Published: December 2007

Abstract
Radioactive tracers have been successfully utilized to interpret the placement of stimulation treatments. A field data acquisition system has been developed to monitor tracer injection in real time. By placing a gamma ray sensor assembly over the stimulation line used in acid, fracture or cement treatments, radioactivity measurements are taken in order to monitor the amount and duration of the tracer being injected. An over the line monitor is connected to a laptop computer in order to record the data. This system insures that the tracer is added in a continuous, controlled manner as required. Software has been developed to enhance the ease of data acquisition in harsh field environments. The equipment is also capable of monitoring other stimulation treatment variables such as pressure and temperature. A description of the hardware and software is followed by several examples in the body of the report.
Benchmarking – A Catalyst for Operational Improvement in the Exploration and Production Industry
Authors: Hinn R. L. 
Published: December 2007

Abstract
Benchmarking has proven to be an important catalyst in the quest to attain significant cost reductions in Amoco's Permian E&P operations. Benchmarking results have been derived from both external and internal efforts. Each of these types of analysis produce a unique data set which can be utilized to foster positive change within an organization.
Percussion Drilling…Is It a Lost Technique? A Review.
Authors: Samuel G. Robello 
Published: December 2007

Abstract
This paper presents a review of the benefits and performance of downhole percussion hammers. The advancement of drilling technology and the extensive use of coiled tubing coupled with different downhole motors prompted another look at the percussion type of drills. Achieving very high extended reach wells also have necessitated a high axial driving mechanism. The potential benefits of the percussion type of drilling machine for future operations are given, supported by the performance of the tools. The use envelope and the benchmarks of the tools by different manufacturers down the years have been discussed. The hammers developed and operated have been supported by enough field runs to prove the sustainment of the tools. Different models of downhole hammers can be categorized as first generation tools which include the developments from early time to the development of Bassinger tools. The second generation tools from post-Bassinger to the recent developments are discussed broadly. The basic principle involved and the necessity to consider the correct stress waveform to simulate the performance of the downhole hammer energy transfer are reviewed.
Underbalanced Drilling, Praises and Perils
Authors: Bennion D. Brant , Thomas F. Brent , Bietz Ronald F. , Bennion Douglas W. 
Published: December 2007

Abstract
Underbalanced drilling has been utilized with increasing frequency to minimize problems associated with invasive formation damage which often greatly reduce the productivity of oil and gas reservoirs, particularly in open hole horizontal well applications. Underbalanceddrilling, when properly designed and executed, minimizes or eliminates problems associated with the invasion of particulate matter into the formation as well as a multitude of other problems such as adverse clay reactions, phase trapping, precipitation and emulsification which can be caused by the invasion of incompatible mud filtrates in an overbalanced condition. In many underbalanceddrilling operations, additional benefits are seen due to a reduction in drilling time, greater rates of penetration, increased bit life, a rapid indication of productive reservoir zones and the potential for dynamic flow testing while drilling.
Underbalanced drilling is not a solution to all formation damage problems. Damage due to poorly designed and/or executed underbalanced drilling programs can rival or even greatly exceed that which may occur using a well-designed conventional overbalanced drilling program. Potential downsides and damage mechanisms associated with underbalanced drilling will be discussed. These include: Increased cost and safety concerns.Difficulty in maintaining a continuously underbalanced condition (due to such factors as pipe connections in rotary drilling, bit trips, mud pulsed logging, bit jetting and flushing effects, localized depletion and subsequent repressurization effects, poor knowledge of initial reservoir pressure, multiple zones with differing initial pressures, slug flow and liquid holdup in the vertical section of the wellbore, frictional pressure drop and mechanical problems with surface equipment or gas supply sources).Spontaneous imbibition and countercurrent imbibition effects.Glazing, mashing and cuttings induced damage.Macroporosity gravity induced invasion.Difficulty of application in zones of extreme pressure and permeability.Political/career risk associated with championing a new and potentially risky technology.
This paper discusses reservoir parameters required to design an effective underbalanced or overbalanced drilling program, laboratory screening procedures to ascertain the effectiveness of underbalanced drilling in a specific application and presents screening criteria with respect to the types of reservoirs which present good applications for underbalanced drilling technology.
Continuous Improvement in Well Profiles and Bits Enables Permian Operator to Optimize Slim Hole Program
Authors: Tank W. , Pohler S. , Felderhoff F. 
Published: December 2007

Abstract
This paper describes the evolution of a slim-hole directional and horizontal drilling program in the Permian basin. The development and application of small-diameter roller cone bits has played an important role in the success of this program. The integration of these bits with specialized motors and fluid systems, has produced optimal well profiles which will be presented and analyzed. Case studies of Marathon wells showing significant per footage cost reductions, increased footage/penetration rate per bit and increased displacement will be presented.
Modeling of Pressure Buildup on a Kicking Well and Its Practical Application
Authors: Miska Stefan , Samuel G. Robello , Azar J. J. 
Published: December 2007

Abstract
This paper describes a new method for prediction of pore pressure and formation permeability from a kicking well. Getting reliable and accurate information about reservoir parameters (when the formation damage is minimal) is of critical importance for making proper well completion decisions. In addition, when a well kicks, inaccurate estimation of the formation pressure may cause loss of equipment and possibly the well and human lives. To combat the above problems, a conventional pressure analysis method is modified to predict the formation pore pressure and estimate directional formation permeabilities from a kicking well. The method is simple, and the only prerequisite is that the buildup data be collected upon shutting-in a kicking well. Examples of using simulated as well as actual field data, are provided to demonstrate the practical application of the method.
Problem Identification and Solution Method for Water Flow Problems
Authors: Pappas James , Creel Prentice , Crook Ron 
Published: December 2007

Abstract
In the past, it was difficult to justify the expense of water control because it often produced poor results. The most commonly used water-control technique, cement squeezing, had only a 50% success rate. Other more exotic treatments had even lower success rates and were performed only as experiments or "last resorts." These unsuccessful treatments often resulted because the source of the problem was not correctly identified. With the tools available today, the essential element of conformance control is identifying the nature and source of the problem. Once the problem is correctly identified, the best material or solution to solve this problem must be determined. The best placement technique must also be determined to ensure that the material or solution is placed where it has the best possible chance of solving the problem.
Addressing poor sweeps, channeling, interwell communi-cation, and other water-control problems is especially important in fields where injection is used to enhance oil production. Chemical analysis and water flow logging can help operators isolate water flow, invasion, and annular leaks that destroy casing integrity and decrease profitability. A case history in-volving five wells demonstrates the use of analytical techniques to identify conformance-control problems. It also focuses on the evaluation and solution processes. In essence, the case indicates the importance of thoroughness. In this case, identification, evaluation, implementation, post-analysis, and re-evaluation were combined into a single process.
On the Physics of Multimechanistic Gas-Water Flow in Fractured Reservoirs
Authors: Chawathé A. , Grader A. , Ertekin T. 
Published: December 2007

Abstract
Multimechanistic flow occurs in reservoirs when the fluid transport is influenced by both, pressure and concentration gradients. In this research, we investigate the dynamics of multimechanistic gas-water transport in fractured systems. To achieve this objective, we have developed a two-phase, two-dimensional dual-porosity, dual-permeability simulator. The details of the simulator development are presented in a previous paper (Chawathé et al., 1996).
Our studies indicate the presence of higher flowrates and cumulative production at early times in systems experiencing multimechanistic flow. This is attributed to the higher drawdowns experienced by such systems. At late times, a "choking effect" is hypothesized to be responsible for higher cumulative production. In this paper, we investigate the physics underlying this multimechanistic flow behavior. We do this by carefully analyzing a fractured system which clearly displays multimechanistic flow characteristics.