bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation for Polymer Damage Aids in Candidate Selection for Removal Treatment
Authors: Carr Michelle A. , Yang B. Helena 
Published: December 2007

Abstract
Poor well performance due to permeability and conductivity damage can often be attributed to unbroken gel residue or inadequately reduced filtercake on formation faces. These forms of polymeric damage can negatively impact production rates by restricting the flow of oil or gas from the formation. Remedial treatments have been applied to wells exhibiting this type of damage using acids, oxidizers and enzymes. These removal treatments, when applied to accurately diagnosed polymer damaged wells and effective breaker systems are utilized, have shown to increase well production dramatically. However, polymer damage is only one of many factors that might be responsible for impeding optimum hydrocarbon flow. Therefore, the key to the success of a removal treatment is proper evaluation for polymeric damage when selecting a treatment candidate.
An improved flowback analysis has been recently introduced as a series of tests for polymer damage and for the evaluation of treatment load recovery. The testing procedures involved in that analysis can also be applied in candidate selection for remedial treatments and for monitoring the resulting clean up progress. Samples are analyzed before and after the treatment to determine total carbohydrate content, molecular weight distributions and the standard pH and viscosity measurements. The utilization of this improved analysis can assist in the selection of appropriate candidates and further direct treatment design. Several case histories on low performance wells are presented and include laboratory data to demonstrate candidate selection. Treatments with enzymes were used and detailed results are provided to evaluate the amount of polymer recovered. This paper also presents a guideline for use in the selection of candidates for remedial treatments.
History Matching and Modeling the CO-Foam Pilot Test at EVGSAU
Authors: Chang Shih-Hsien , Grigg Reid B. 
Published: December 2007

Abstract
A pilot area in the East Vacuum Grayburg-San Anders Unit (EVGSAU) was selected for a comprehensive evaluation of the use of foam for improving the effectiveness of a CO flood. The response from the foam field trial was very positive, it successfully demonstrated that field application of CO-foam is a technical viable process for improved oil recovery (IOR). A pseudo-miscible reservoir simulator, MASTER, which was recently modified by incorporating a newly developed foam model, was used to conduct a history match study on the pilot area at EVGSAU to understand the process mechanisms and sensitive parameters. The ultimate purpose was to establish a foam predictive model for CO- foam processes.
In this paper, the history match results are presented. The important modeling considerations that led to an acceptable history match are highlighted and discussed. Finally, the simulated results of a foam predictive ease are presented. The injection schedule of the foam predictive ease was specifically selected to mimic the filed injection schedule used in the foam pilot test at EVGSAU.
The simulated results are consistent with the field pilot test results. Overall, the foam model is found to be adequate for field scale CO-foam simulation. The results also confirm that the communication path between the foam injection well and the offending well had a strong impact on the production performance.
P. 365
Drill Pipe/Coiled Tubing Buckling Analysis in a Hole of Constant Curvature
Authors: Qui Weiyong , Miska Stefan , Volk Leonard 
Published: December 2007

Abstract
Lateral/multilateral drilling technique has significant potential to reduce well costs and increase hydrocarbon production. Coiled tubing drilling (CTD) takes a very substantial role in lateral/multilateral drilling. Well cost reduction in CTD can be achieved by transmitting weight to the bit effectively and preventing coiled tubing (CT) failure/fatigue and lock-up occurrence. To acquire this goal, an accurate buckling model becomes essential. This paper presents a new buckling model in a hole of constant curvature (such as the build section of a horizontal well). It starts from the formulation of the change in the strain energy of bending, the potential of the axial force and the potential of the radial force. Using the energy method, new equations are derived to predict the axial compression force to maintain stable sinusoidal configuration and the axial compression force required to produce helical configuration. Examples show that the axial compression loads to produce sinusoidal and helical forms are much larger than those in deviated wells, especially in short radius wells.
P. 385
An Integrated Study of Imbibition Waterflooding in the Naturally Fractured Spraberry
Authors: Guo B. , Schechter D.S. , Baker R.O. 
Published: December 2007

Abstract
In order to understand waterflood performance in low permeability, naturally fractured Spraberry Trend Area reservoirs, an integrated study of imbibition waterflooding has been performed. In this study, oil production during imbibition waterflooding in naturally fractured reservoirs has been mathematically analyzed on the basis of the rate law that governs mass transfer. Analytical models for decline curve analysis based on imbibition theory have been developed. Imbibition and capillary pressure experiments have been conducted in the laboratory using reservoir crude oil, synthetic reservoir brine, and low-permeability reservoir cores under room and reservoir conditions. Remarkable consistency has been observed using experimental data to scale-up and match reservoir performance. It is found that slow imbibition of water into the weakly water-wet rock matrix is the limiting step for oil recovery during waterflooding. This study suggests that better waterflooding should be sought in areas of high matrix permeability, high fracture intensity, and significant oil saturation.
P. 407
Simple Models of Water Imbibition and Gravitational Drainage of Oil in Rock Blocks
Authors: de Swaan Abraham 
Published: December 2007

Abstract
The oil outflow from porous-rock blocks due to water imbibition interchange and to gravitational drainage, are described by schematic mathematical models that include actual petrophysical properties of the fluids as well as dimensions of the blocks. The models were validated through comparison of their results with those of numerical simulations of these problems. The simulations cover wide realistic ranges of values of the properties involved.
The models can be used to compute the expected behavior of blocks in fractured reservoirs and to calibrate block behavior in numerical simulators that use parameters instead of actual properties of the fractured porous media.
P. 71
Novel Technology for Flame & Gas Detection in the Petrochemical Industry
Authors: Spector Yechiel , Jacobson Esther 
Published: December 2007

Abstract
A reliable and high performance novel method of Flame and Gas Optical Spectral Analysis (line of sight) was developed to meet the specific flame and gas detection needs of the petrochemical industry.
Petrochemical industries, especially the offshore and unmanned (unattended) areas in onshore refineries, pose a major safety hazard with respect to potential explosions and fire events. Unwanted fuel spills or fugitive flammable vapour clouds, migrating along congested pipe lines and hot production areas may cause upon ignition significant loss or damage. To help prevent events like the catastrophic fire that destroyed the offshore oil platform Piper Alpha in July 1988, a reliable and fast gas and flame detection system can be used to trigger effective risk management actions.
The present paper describes a patented method of Triple Optical Spectral Analysis employed for the detection of various gases in the air according to their unique "spectral finger print" absorption characteristics of radiation, as well as for analysis of emission and absorption radiation from combustion processes (hot CO2) for flame detection purpose.
The method has been applied in the development of unique gas and flame monitoring systems designed for "high risk - harsh/extreme weather conditions continuous operation" - These systems have been recently installed on several offshore platforms and oil rigs as well as on "Floating Production Storage and Offloading" - FPSO vessels.
The systems advantages and limitations as well as several installations and test data are presented. Various atmospheric conditions (direct and reflected sunlight, fog, rain, hail, snow) as well as false alarm stimulus (from radiation sources, flare stack, black body radiation, smoke, CO2 and atmospheric gases) are discussed.
P. 93
A Stage of Application Reservoir Management Process on Pantai Pakam Timur High Permeability Gas Field: A Field Case
Authors: Briantoro Cecep , Miftah Akhmand , Widjiono S. 
Published: December 2007

Abstract
The modem reservoir management process involves establishing a purpose or strategy and developing a plan, implementing and monitoring the plan, and evaluating the results. This paper present application of them on Pantai Pakam Timur gas field.
Pantai Pakam Timur is a new gas field in Pertamina Operasi Rantau Aset Pangkalansusu. This field located in the onshore portion of the North Sumatra Basin Indonesia. The Area is approximately 15 km North-West of Medan. The Pantai Pakam Timur Structure was discovered as gas and condensate entrapment in the major of Belumai formation (Z-238S,2400), Apart from that, there is Shallow prospect of Keutapang formation (Z-127S) is known brightly as "Strong reflection" in Seismic which about 1300 milli Sec.
Since the test production has just started about 9 years ago, it is very important evaluate the reservoir characteristics to obtain reliable data to set up the future field development strategy. The Pressure Transient testing of several wells show existing very difference of rock characteristic (the main is permeability) between deep zone (Z-238S,2400) and shallow zone (Z-127S), which on deep zone less than 5 Md, then on shallow zone (under discussion) the fantastic permeability had been found, they were greater than 500 MD from PPT-05A and PPT-06 wells.
The monitoring and evaluating are being performed through several technical approaches respectively, which are continuous monitoring on production performance, evaluating on well testing analysis and evaluating the P/Z versus Cumulative gas production plot, that is used by comparing toward Volumetric method, in line to Reserve estimation.
Furthermore the gas deliverability was conducted based on modified isochronal test results of several existing wells and appropriate Reserve to get more realistic and maximize the potential. (The strategy and developing stage).
P. 127
Advances in the Modeling of the Stratified Flow of Drilled Cuttings in High Horizontal Wells
Authors: Santana M. , Martins A.L. , Sales A. 
Published: December 2007

Abstract
The study of stratified solid liquid annular flows is of great interest of the petroleum engineering, specifically in the drilling area. This kind of flow describes the phenomena involved in the transport of the solids generated by the bit during the drilling of a horizontal or highly inclined well. In these operations there is tendency. due to the action of gravitational forces, of solids deposition in the lower part of the annular region formed by the wellbore walls and the drill column. One approach is the well known Two Layer Model, originally proposed by the mining industry to simulate the transport of solids at high concentrations in pipes. This model has been adapted to the problem of drilled cuttings transport, by the introduction of elements to model the non Newtonian behavior of the fluid and the annular geometry and is currently in use for design and troubleshooting in drilling operations. Some limitations of the model in the reprodttction of the role of rheology in the transport of solids motivated the formulation of more precise hypothesis. This paper deals with the analysis of the effect of the improvements in the final results of the model. Such improvements include the experimental determination of interfacial friction between the solids bed and the suspension. new criteria for solid liquid slip conditions and the choice of different rheological models.
P. 381
Techniques for Coping With Missing Data in Pressure Transient Tests
Authors: Aly A.M. , Bastian P.A. , Lee W.J. 
Published: December 2007

Abstract
This paper presents techniques we developed to cope with data missing from most of 72 buildup tests run between 1956 and 1986 in a large North American oil field. Most of the tests were run before the industry fully appreciated the need for early-time data and for measurement precision sufficient to generate useful derivative plots. Frequently missing were pre-test rates, time and flowing bottom-hole pressure at shut-in. We needed the buildup test analysis to help with reservoir description in an ongoing integrated study of the reservoirs in this field.
"Conventional" analysis suggested a large wellbore storage and skin factors of -4 to -5 in these unstimulated wells, assuming that the reported time and pressures at time zero were correct. Our work showed that missing only the first half-hour of the test can account for these anomalies. As a result, we developed guidelines for identifying invalid tests and for correcting erroneous interpretations in many of these tests to determine permeability and average pressure.
This paper helps the engineer to cope with missing data from field pressure tests and still be able to salvage the test and determine permeability and average pressure which are essential for reservoir characterization.
The technical contributions of this paper include criteria and techniques to cope with missing data in "old" field pressure tests; a procedure for obtaining useful permeability estimates and average drainage areas pressures from these tests; and guidelines for identifying tests that are simply invalid as reported because of incorrect shut-in times and missing initial shut-in pressures.
P. 389
Improved Selection of Candidates for Stimulation Treatment in the Wilcox Play in the South Texas/Mexico Border Area
Authors: Boonen P. , Byrd A. C. , Frisch G. , Kessler C. , Kubelka G. , Nixon Mark 
Published: December 2007

Abstract
A particular South Texas gas field has suffered severe production decline in the last two years. The wells were completed in the Wilcox formation, which extends from the Burgos Basin in Mexico through Texas into Louisiana. The object was to identify and treat potential producing zones in all existing wells to increase production. Hydraulic fracturing is the preferred stimulation technique in these formations. Typically multiple zones are fractured in each of the wells. The stimulation treatments are designed with the aid of 3D hydraulic fracture models. Wireline logs provide the most comprehensive and continuous input parameters in such modeling for borehole stress profile, permeability index, elastic moduli, lithology, porosity and fluid saturation's. Existing open-hole wireline logging data were reprocessed using a new technique which provides all the available logging data in a format suitable for direct input in 3D hydraulic fracture models. An automatic zoning technique divides the data into consistent intervals based on stress contrast. The representative design parameters are then computed for each zone. The outputs are a blocked stress profile and a set of zoned fracture design parameters.
This new technique was used to evaluate all the stimulation candidates in the field. One well was bypassed for treatment altogether, saving $500,000 to $700,000 on a stimulation that would have had a marginal result at best. In another well, the log was used in combination with a Fluid Efficiency Test (FET) and a Step Rate Test to show essentially no leak-off, and hence very low permeability in one zone. This lower sand was skipped, and upper zones were fractured to increase gas production from 550 MMCF/D to 1,300 MMCF/D.
Stimulation of a Low Permeability Natural Fractured Reservoir in the North-West German Carboniferous
Authors: Dietzel H.J. , Koehler M. 
Published: December 2007

Abstract
In this paper the development of a low-permeability natural fractured reservoir in the north-west German carboniferous is presented as a characterization of the reservoir its structural and facial properties are described including log and core analysis.
The reservoir consists of a series of tight sandstones separated by shales over a gas column of up to 900 m. As the natural fractures seem at least in parts to intersect the shale barriers, vertical interconnection of sandstone layers is probable. The permeability of the sandstones ranges from 0.01 md to 0.1 md at porosities from 3 % to 11 %. Thus, the production is nearly exclusively related to the natural fracture system. Wells without initial connection to the fracture system show only marginal or even no production after perforation. To get a link of the perforated intervals to the fracture system, hydraulic fracturing operations have been successfully applied~ Due to the poor prefrac rates, the data basis was insufficient for proper frac design. Based on the increasing experience of the preceding jobs a rough sizing of the amount of proppants to be placed gave the outlines for the frac design, which was then fine-tuned during an extensive data frac prior to the main frac. To overcome tortuosity and multiculture problems, proppant plugs were pumped during the data frac. In this paper frac-design, job description and post frac analysis of various frac operations are compared. The evaluation of transient pressure tests connected to the frac operations is presented. In conclusion the development strategy for this natural fractured reservoir, based on the increasing experience with successful hydraulic fracturing, is pointed out.
P. 83
Practical Production Data Analysis
Authors: Frantz J.H. , Spivey J.P. , Hopkins C.W. 
Published: December 2007

Abstract
This paper presents several production data analysis case histories. The primary purpose of this work is to illustrate the practical application of advanced production data analysis methods in low permeability gas reservoirs. Production data provide important information about reservoir quality and volume and the stimulation effectiveness. The analysis results can provide estimates for permeability-thickness product, skin factor or fracture half-length, gas in place, and drainage area. Pressure transient information can also be integrated with production data analysis to further characterize the reservoir.
Practical applications of production data analysis results include estimating short- and long-term production rates, estimating reserves, designing/evaluating stimulation (and restimulation) treatments, predicting and evaluating production increases from changes in flowing well pressure (plunger-lift and compressor installations), determining infill well potential and optimal well spacing, and identifying natural fracture and/or layered behavior. We will show examples of the above applications using actual field data. New type curves were also used in this work to analyze difficult datasets and to provide a starting point for more sophisticated history-matching methods. The final portion of this paper will include recommendations for field data collection and database utilization.
P. 231
The Relationship Between Fracture Treatment Shut-ins, Reservoir Permeability and Production Responses
Authors: Harkrider J.D. , Aud W.W. , Whittington J.O. 
Published: December 2007

Abstract
A basic search for geologists and engineers is to understand the flow potential from a reservoir. Though factors, such as reservoir pressure, net pay, reservoir heterogeneities and propped fracture lengths influence the well's productivity after completion, in-situ reservoir permeability dictates the relative magnitude of the production response. As such, in-situ permeability is a key variable for the economics of the well and future development opportunities. A method is presented that evaluates the pressure falloff response of fracture treatment pump-in tests for determining, on a negative basis, the reservoir permeability. A direct correlation is then made between the pump-in derived permeability value and the subsequent production response.
Conventional methods for determining reservoir permeability are often limited in the area of reservoir sampled. An alternative method is introduced that uses three-dimensional modeling of the pressure fall off responses to predict reservoir permeability. By using pump-in tests, communication with the formation is improved with a larger sampling of the reservoir area through the fracture face. This results in more of a macro permeability measurement as compared to other sampling methods. A comparative analysis between pump-in derived permeabilities and the associated production response provides a definitive measurement for developing a predictive reservoir permeability correlation.
This paper demonstrates the evaluation technique by presenting case studies in the Lewis, Almond, Frontier and Red Fork formations. The case studies show the relationship between the leakoff coefficient value, the pump-in derived reservoir permeability and the post-treatment production response. By relating these variables, a relative indicator of rock quality and flow capacity for a given reservoir can be determined during and immediately following the hydraulic fracture treatment. Given a statistically valid data set, the development of a permeability indicator provides the ability to predict production responses based on the pressure fall off observed while treating the well. Application of this technique may eventually lead to a reservoir/production tool that provides "real-time" go/no-go decision capabilities for geologists and engineers in completing multiple intervals in a well.
P. 395
Pressure-Dependent Leakoff in Fracturing Field Examples from the Haynesville Sand
Authors: Rollins K. , Hyden R.E. 
Published: December 2007

Abstract
This paper presents a field history of Haynesville Sand fracturing in which pressure-dependent leakoff has been encountered. Pressure-dependent leakoff has been identified and evaluated theoretically by others (Mukherjee et al.; Walsh, Warpinski, and Ayoub et al.). These examples are presented in a follow up of Barree and Mukherjee's paper in which simulation illustrates how 6-function plots can help detect pressure-dependent leakoff from pressure-fall off data.
6-function plots have helped describe the nature of a problem noted in some Haynesville Sand jobs in which bottomhole treating pressure was extremely sensitive to proppant concentration, often causing premature screenout. The screening technique has led to job modifications that allow successful completion of the stimulations. This paper summarizes one operator's ongoing experience with managing the job design to allow for fairly successful stimulation under these circumstances.
P.433
Hydraulic Fracturing Provides Production Gains in Kalchinskoye Oilfield of Western Siberia
Authors: Kondratoff L.B. , Khasanov R.N. , Budziak J.J. , Hagel M.W. 
Published: December 2007

Abstract
Approximately ten years have passed since western hydraulic fracturing technology was introduced 1 to the oilfields of Western Siberia. This paper examines how that technology is now being applied to the Kalchinskoye oilfield in the southern reaches of the Ob River basin of Western Siberia.
The Kalchinskoye oilfield, being developed through joint venture operations, is best characterized as a low permeability, normally pressured, Cretaceous/Jurassic sand sequence with low gas to oil ratio. This paper discusses reservoir characteristics, well candidate selection, treatment design and performance, and post-treatment analysis. It also details the value of good oilfield operating practices to achieve and maintain fracturing success.
P. 443