bluuebunny/crossref_metadata_2025_split huggingface dataset:
Investigation of Waterflooding and Gas Cycling for Developing a Gas-Condensate Reservoir
Authors: El-Banbi Ahmed H. , Aly A. M. , Lee W. J. , McCain W. D. 
Published: December 2007

Abstract
This paper presents the results of a full field compositional reservoir simulation study that compares the application of waterflooding and gas injection to a rich gas-condensate reservoir. Fluid (water or gas) injection is used to maintain the reservoir pressure above the dew point pressure and prevent condensate dropout in the reservoir. The simulation study shows that water injection is a viable option in producing gas-condensate reservoirs.
The study shows that both water injection and gas injection result in higher recovery factors than normal depletion. Although gas injection showed higher condensate recovery factors, it may not be economical due to the required large initial investment, higher operating costs, and delay of gas sales. For the water injection to be effective, the reservoir should not be flooded completely with water. Rather, the reservoir should be blown-down before water invades the producing wells. Factors that affect the recovery of gas condensate reservoirs under water injection are highlighted. These factors include time to blow-down and imbibition relative permeability curves. Sensitivity analysis results are presented for these factors.
Water injection has a major advantage over gas injection. In water injection produced gas can be immediately sold and compression cost is saved.
Gel Slugs: A Near-Wellbore Pressure-Loss Remediation Technique for Propped Fracturing
Authors: Chipperfield S. T. , Roberts G. A. , Miller W. K. , Vandersypen R. S. 
Published: December 2007

Abstract
A significant factor in the success of propped fracturing is the complexity of the created near-wellbore fracture geometry. This paper discusses the cost-effective use of high viscosity gel slugs to reduce near-wellbore complexity (measured as Near Wellbore Pressure Loss or NWBPL) in a high temperature, hard rock environment to a level acceptable for successful fracture stimulation. Determination of a fluid dependent, acceptable level of NWBPL has been obtained through extensive field measurements. Knowledge of this limit assists in determining where gel slugs are required and whether a gel slug injection can be categorised as a success or failure.
The benefit of using higher viscosity fluids in propped fracture treatments for NWBPL mitigation is well documented. However, in some environments, such as those described herein, use of higher viscosity for the propped treatment would be both cost prohibitive and possibly detrimental to well production. A preferred technique involves the removal of NWBPL with a higher viscosity slug and, once assured of gel slug success through accurate diagnosis, a lower gel loading propped treatment can be conducted.
This paper provides guidelines for field application of the gel slug methodology and discusses its inclusion in a pre-frac injection sequence. Like other NWBPL remediation techniques, gel slugs may not provide immediate positive results. Limitations of this technique and conditions for its appropriate use are also included.
Reservoir Souring in the Caroline Field
Authors: Seto C. J. , Beliveau D. A. 
Published: December 2007

Abstract
This paper presents a novel mechanism for reservoir souring which is based on the evolution of acid gas from sour aqueous phases present in the reservoir. Souring is a widespread phenomenon in seawater floods. The accepted mechanism in these cases is biogenic activity of sulfate reducing bacteria (SRB).
Field data from the Caroline reservoir indicate that it is souring. What is intriguing about this field is that it is being developed via conventional blowdown depletion, which suggests that SRB is not the cause. The mechanism presented is based on the physical principles of Henry's Law, which govern the solubility of hydrogen sulfide (H2S) in water.
Through material balance analysis and reservoir simulation, the Caroline field is presented as a case study where this mechanism is plausible. Reservoir simulation which account for this phenomenon was subsequently used to generate more realistic gas composition, thus optimizing the operations of the $1 billion Caroline facility.
CBM Resource Potential in the Plains Area of Alberta
Authors: MacLeod R. Keith , Cech R. , Hughes Dave 
Published: December 2007

Abstract
The National Energy Board (NEB) forecasts that unconventional gas will be required to meet Canadian demand by the year 2008 and could constitute up to 65 per cent of supply by 2025. Our study of the coalbed methane (CBM) potential for the Plains area of Alberta estimates a constrained gas resource of 187 Tcf of gas-in-place. Our study considered the major prospective coal horizons (Cretaceous to Early Tertiary), as well as the technical and fiscal constraints to development. Cost supply curves for future CBM development provide insight into the gas prices required to meet the NEB s supply deficiency.
Effects of Geologic Variables on Cleat Porosity Trends in Coalbed Gas Reservoirs
Authors: Nelson Charles R. 
Published: December 2007

Abstract
Naturally occurring microfractures, called cleats, provide the permeability essential for bulk fluid flow in coalbed reservoirs. The bulk fluid flow, in turn, is controlled by the cleat properties, specifically their orientation, spacing, compressibility, and effective porosity. A two parameter, geologic process-based model for predicting the effective cleat porosity of coalbed reservoirs was developed from an analysis of cleat property data for San Juan Basin Fruitland Formation coal. The cleat property data indicate that thermal maturation and effective stress act in opposite directions on the effective cleat porosity of Fruitland Formation coal. These two variables are the basis for the geologic process-based model for calculating effective cleat porosity values.
Integrated Field Study for Production Optimization: Jonah Field — Sublette County, Wyoming
Authors: Eberhard M. J. , Mullen M. J. , Seal C. A. , Ault B. P. 
Published: December 2007

Abstract
The Lance formation in the Jonah field is an overpressured, tight-gas sand that requires hydraulic fracturing for economic production. Because of large gross intervals containing several individual sands, limited entry has been the typical fracturing technique. Wells can have more than 30 individual sands that are completed with multiple fracture treatments; however, production log data indicate that only 58% of the perforated sands contribute to production. Production optimization is dependent on improving the percentage of completed pay contributing to production.
A detailed field study was conducted to determine pay identification and best practices for completions. In the study, 44 wells in the Stud Horse Butte area were analyzed. The study comprised detailed log analysis, fracture treatment data, production data, reservoir analysis, and completion practices. Some of the processes used were log normalization, traditional statistical analysis, and reservoir modeling. Log and treatment data were also analyzed with an artificial neural network (ANN).
Design and Interpretation of Long-Term Tests in the Mahogany Field, Offshore Trinidad
Authors: Maharaj S. , Jones J. R. , Mackow H. M. , Lachance D. P. 
Published: December 2007

Abstract
In this paper, we present the details of how four extended well tests in the Mahogany field, offshore Trinidad, were designed, executed, and interpreted. While much of the interpretation for a given test can be done using standard analytical software, we pay special attention to the need for numerical simulations of the measured responses to establish connected volumes and previously unidentified flow barriers.
To establish how long these nine wells can produce the required contract rates and, hence, the required date of renewed drilling, a program for extended well testing was developed. Each well was tested according to the following sequence: clean up flow followed by a stabilizing shut-in period, a forward sequence flow-after-flow ending with an extended flow period, and extended shut-in. The lengths of each of these test sections is planned to vary from well to well but, in general, the entire test sequence was designed to be 35-60 days long. These tests are intended to establish permeability, mechanical and turbulent skin factors, and the areal extent of the sand connected to the test well.
JAPEX/ JNOC/ GSC MALLIK 2L-38 Gas Hydrate Research Well, Mackenzie Delta, N. W. T.: Overview of Field Operations
Authors: Ohara T. , Dallimore S. R. , Fercho E. 
Published: December 2007

Abstract
The Mallik 2L-38 well was drilled in February and March, 1998 to a depth of 1150m at a site located in the Mackenzie Delta, N. W. T., Canada. Undertaken as a collaborative agreement between the Japan National Oil Corporation and the Geological Survey of Canada, the well was conducted as a research and development project with engineering goals to evaluate various technologies fordrilling and coring gas-hydrate-bearing strata. The Mallik site was chosen as it had favorable logistics and was thought to contain a thick interval of gas hydrates between 897 and 1110 m depth. Drilling operations included a surface hole (with 8 coring runs) to 687m for installation of a 340mm surface casing, and a main hole (with 16 coring runs) to the target depth of 1150m. The drilling system utilized a KCl/polymer drilling mud that was cooled to 2°C using a plate type heat exchanger. Drilltreat, a chemical mud additive was used in the main hole to stabilize gas hydrate within drill cuttings and formation sediments. Drilling operations were conducted without any serious hole problems, accidents, or mishaps. However, delays were caused by adverse weather and mechanical problems, causing adjustments in the overall program. Coring in the main hole was particularly successful allowing evaluation of four different core barrels. Gas-hydrate-bearing core was collected in a variety of sediments between 886 and 952m. The excellent condition of the core samples, controlled gas hydrate dissociation within the mud column, and near-gauge hole, confirmed that the combination of chilled mud with Drilltreat performed extremely well.
Forecasting World Natural Gas Supply
Authors: Al-Fattah S. M. , Startzman R. A. 
Published: December 2007

Abstract
World gas supply forecasting has proved difficult because its exploration, transportation, and customer bases are so heavily dependent on fluctuating economic factors. Our recent study showed that the conventional Hubbert model with one complete production cycle is not appropriate for use in forecasting gas production trends for most gas producing countries.
This paper presents our forecast for the world's supply of conventional natural gas to the year 2050. We used a multicyclic Hubbert approach to develop 53 country-specific gas supply models that enable production forecasts for virtually all of the world's gas. The multicyclic modeling approach is presented in a convenient form that makes production data exhibiting two or more cycles easier to model. These models were aggregated to the regional level and to the world level. Supply models for some organizations (e.g. OPEC, non-OPEC, OECD) were also developed and analyzed.
Our results indicate that the world's supply of natural gas will peak in 2014, followed by an annual depletion rate of 1%/yr. A regional analysis indicates that gas production of some regions will peak soon. North American gas production is currently (1999) at its peak. West European gas production is expected to peak in 2002. The countries of the former Soviet Union and Middle East, which comprise about 60% of world's ultimate recovery of natural gas, will be the main sources of world gas supply in the future.
Phase Diagram Optimization in Micellar Systems
Authors: Baviere M. 
Published: December 2007

Abstract
An optimization of micro emulsion compositions is presented for a hydrocarbon/water ratio considered as characteristic. By studying the influence of the main parameters (molecular weight of hydrocarbon and amphiphilic compounds, surfactant to co surfactant concentration ratio, salinity and temperature), the results obtained show an optimal value for each of them, corresponding to the use of a minimal amount of amphiphilic compounds.
An interpretation is given, based on the equilibrium of hydrophilic and hydrophobic tendencies within the surfactant molecule, and supported by interfacial tension measurements in simpler diphasic systems where the partitioning of the surfactant between aqueous and hydrocarbon phases can be determined.
Thus a set of relationships between the parameters is established that may prove useful, from a practical point of view, in the choice of formulations. In particular, solutions are given for high temperature and brine concentration.

INTRODUCTION
Micellar solutions used in enhanced oil recovery present certain difficulties, as regards both their preparation and their application. These difficulties are further increased by economic requirements as the limits imposed by technical possibilities and profitability narrow the field of possible compositions. In the application of this process, guides are therefore required to reach optimal formulations, i. e., in particular, the use of a minimal amount of amphiphilic compounds.
The search for maximal interfacial efficiency of surfactant entails establishing conditions in which there is a maximal concentration at the interfaces. This should take place when the amphiphilic molecule shows minimal affinity in the aqueous phase and hydrocarbon phase simultaneously; the hydrophilic and hydrophobic tendencies are then very close and balance each other. A similar phenomenon appears when a minimal interfacial tension is obtained in the systems composed of a hydrocarbon and a surfactant diluted aqueous solution. The advantage of these systems is that the partitioning of the amphiphilic product is easily measured and the affinity equilibrium thus is well shown.
A Successful Low Tension Waterflood Two-Well Test
Authors: Murphy Charles L. , Thiede David M. , Eskew James O. 
Published: December 2007

American Institute of Mining, Metallurgical, and Petroleum Engineers, Inc.

Abstract
Mobil's Low Tension Water Flood (LTWF) process was successfully tested in the West process was successfully tested in the West Ranch field in South Texas in 1974. The LTWF process reduced the oil saturation to about 5 process reduced the oil saturation to about 5 percent of the pore volume in the swept area. percent of the pore volume in the swept area. Test results show that it is possible to flush reservoir brine from the 41A formation and replace it with low salinity water. Chemical requirements under dynamic reservoir conditions were established.

Introduction
Mobil Research and Development Corp. developed a surfactant waterflooding, improved recovery process to recover oil from reservoirs that are near their conventional waterflood residual oil saturation. This process is based on the use of surface-active chemicals to reduce the interfacial tension between the residual oil and the displacing aqueous phase so the residual oil can be mobilized and displaced from the trapping pore spaces. Mobil calls its surfactant waterflooding process the Low Tension Water Flood (LTWF) process. Variations of the LTWF process have been, or are being, field tested in the Looma Novia field, West Burkburnett field, Salem unit, and elsewhere.
This paper describes a successful, but limited, test of the LTWF process in South Texas in late 1974. The paper summarizes the objectives, results, and major design and operational features of a two-well (injection well, observation well) reservoir evaluation field test performed in the 41A First Stringer of the West Ranch field. The purpose of the test was to determine if portions of the LTWF process would operate satisfactorily in the West Ranch 41A formation, and to assist in the scale up of laboratory data. The results would be used to design a larger-scale LTWF test in the same field.

LTWF Process
Mobil's LTWF process, as applied in the West Ranch field, consists of the sequential injection of six aqueous slugs containing prescribed concentrations of various chemicals. prescribed concentrations of various chemicals. The chemical content of each slug, as designed specifically for the 41A zone of the West Ranch field, and the function of each slug, are detailed in Table 1. The concepts behind Mobil's LTWF process and the role of the different LTWF chemicals and slugs were reported previously by Foster. previously by Foster.
True Expansive Characteristics of Commercially Available Expansive Cement Under Actual Well Conditions
Authors: Beirute Robert M. 
Published: December 2007

American Institute of Mining, Metallurgical, and Petroleum Engineers, Inc.

Abstract
The Western expansion meter (WEM) was utilized to continuously measure the expanding characteristics of commercially available expansive cements under simulated well conditions of temperatures and pressures. A detailed description of the WEM was given in a previous publication. This paper previous publication. This paper deals with experimental results obtained with the WEM. Specifically, the following studies were performed on expansive cements using the expansion meter:Age of the cement sample — Its effect on the expanding behavior.Mixing procedure — Its effect the expanding behavior.Different samples — Reproducibility of the results from batch to batch.Temperature — Effect of temperature on the expanding behavior of neat expansive cements.Retarders — Effect of retarders on the expanding behavior at different temperatures.Effect of raising temperature Expanding behavior under conditions of raising temperatures on retarded expansive cements. Temperature increasing from circulating to static.

Introduction
For years the construction industry has fought the problem of drying shrinkage in concrete. Standard concretes present a reduction in volume as they present a reduction in volume as they dry after setting. This volume reduction can produce cracks in the concrete due to the development of tensile strengths. Expansive cements are manufactured to compensate for this drying shrinkage by expanding during this critical period.
Chemically, expansive cements are similar to regular Portland cements, except for the presence of an anhydrous calcium sulfoaluminate (4CaO.3A12O3.SO3).
This compound, hydrates to form ettringite.
A Novel Approach for Monitoring of CaCO3 and BaSO4 Scale Formation
Authors: Morizot A. P. , Neville A. 
Published: December 2007

Abstract
To date much emphasis on scale inhibitor evaluation and studies of scale kinetics has been given to studies using static beaker tests. This paper describes an electrochemically based technique, which allowed the extent of scaling on a solid surface to be determined in presence and in absence of scale inhibitor. The ability of the technique to provide kinetic information on surface scaling will be demonstrated with two kinds of scale. Finally the potential for this technique as a method for on-line monitoring of scale formation downhole will be discussed.
Comprehensive Evaluation of Fractured Gas Wells Utilizing Production Data
Authors: England K. W. , Poe B. D. , Conger J. G. 
Published: December 2007

Abstract
The ability to determine the effective half-length and conductivity of hydraulic fractures is important for estimating a well's long-term production performance. The determination of these properties, along with the formation effective permeability, can result in more accurate predictions of the ultimate hydrocarbon recovery. In very low permeability reservoirs, fracture half-length is the key to optimum reservoir development. Being able to quantify these properties also allows for improved understanding of the effects of treatment design changes. Post-treatment pressure buildup testing has been the most common method for determining the effective length of hydraulic fractures. One of the major drawbacks of the pressure transient test in very low permeability reservoirs is the extremely long shut-in time required to observe a sufficient amount of the fractured well transient behavior to properly characterize the formation and fracture properties. This long shut-in time is undesirable due to the fact that the well is not able to produce and generate revenue during this time.
This paper reports on the most recent results of an ongoing study of the production performance of hydraulically fractured wells. The focus of the study is a comparison of the performance of conventionally fractured wells and those that have been completed with the treated water and low proppant concentration ("waterfrac") technique. A new evaluation technique for comparing the effectiveness of the treatments utilizing production data is introduced. The advantages and limitations of the production data analysis technique are discussed, as well as an improved understanding of the results of waterfrac treatments in low permeability gas reservoirs.
The use of a comprehensive suite of analysis techniques for the production performance of fractured wells to obtain estimates of fracture half-length, fracture conductivity and formation effective permeability is detailed. Specialized diagnostics, performance history matching with analytic solutions and specialized type curve analyses have been used for several areas to estimate the fracture and formation properties from the bilinear, formation linear and pseudoradial flow regimes.