bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Effects Of Retrograde Liquid Condensation On Single Well Productivity Determined Via Direct (Compositional) Modelling Of A Hydraulic Fracture In A Low Permeability Reservoir
Authors: Carlson M. R. (Mike) , Myer J. W. G. (John) 
Published: December 2007

Abstract
Development of a retrograde condensate reservoir required accurate well productivity predictions for a capital commitment to gas processing facilities. Historically, Fussell identified that liquids condensing in the reservoir will result in a substantial productivity impairment. A single well model, which included a hydraulic fracture as part of the grid system, was developed to perform sensitivities for well test interpretation and to predict long term performance. Interesting results were obtained. The productivity of fractured wells was not impaired to the degree expected. Radial modelling confirmed the results obtained by Fussell. Current simulation technique allows for direct modelling of a hydraulic fracture instead of using an equivalent well bore radius. The distribution of pressure drawdown and condensate dropout around a hydraulic fracture results in limited productivity impairment. The methodology used and the results obtained are described.
Viscosity Behavior of Carbon Dioxide Treated Cut Bank Crude Oil
Authors: Cady G. V. , Mosawi Houssain 
Published: December 2007

Abstract
Carbon dioxide injection, either by huff and puff or displacement operations, results in a crude oil viscosity reduction at pressures below the miscibility conditions. Carbon dioxide miscibility occurs in reservoirs at miscible temperature and pressure, but these conditions are not possible in shallow reservoirs. Improved oil recovery in a shallow reservoir depends on the degree of viscosity reduction at the reservoir temperature and pressure. A recovery project's success depends on the interaction between the carbon dioxide and the reservoir system.
A research project carried out at Montana Tech to study the viscosity reduction and carbon dioxide solubility in Cut Bank crude oil at the reservoir's prevailing temperature and near fracture pressure shows a viscosity reduction ratio (crude-carbon dioxide mixture to original dead oil viscosity) of 0.22 at a pressure of 1000 psig and 90°F. An original mobility of 2 0 Md/cp improves to 91 Md/cp under a carbon dioxide recovery process at or near the reservoir's fracture pressure.
Based on our research, improved oil recovery operations in the Cut Bank Field, Montana, is viable when using a commercial on site carbon dioxide recovery or generating system to minimize the cost of CO2transportation. The major benefits ar oil viscosity reduction, mobility ratio improvement, gas drive, and crude oil swelling.
Quantitative Evaluation of Coal Seam Gas Content Estimate Accuracy
Authors: Mavor Matthew J. , Pratt Timothy J. , Nelson Charles R. 
Published: December 2007

Abstract
The proper measurement and analysis of gas desorption data from freshly cut coal samples is crucial to reliably predict the gas production performance and reserve potential of coal seam gas reservoirs. The technical literature offers may procedures for evaluating the total sorbed gas content of coal samples. This paper presents evaluations of the accuracy and comparability of gas content estimates for freshly cut San Juan Basin Fruitland Formation and Piceance Basin Cameo coal samples obtained using commonly practiced analysis procedures. Benchmark (or "ground truth") gas content values were assembled from pressure core and sorption isotherm data for comparison against gas content estimates obtained from conventional whole core, sidewall core, and drill cutting samples. Lost gas content estimate accuracy determined by the Direct (U.S. Bureau of Mines) Method,1,2,3,4 the Smith & Williams Method,5,6 and the Amoco Method7,8 was evaluated and compared. Assessments were also made of the sources and magnitudes of sampling and procedural method errors on the accuracy of the gas content estimates. The choices of sample type, gas desorption temperature conditions, and lost gas analysis method significantly affected the accuracy of the gas content values. The Direct Method analysis of conventional whole core, reservoir temperature gas desorption data provided the most accurate gas content values. Using ambient temperature gas desorption conditions rather than reservoir temperature conditions is the greatest source of error in gas content estimates.
Estimation of AOFP and Average Reservoir Pressure From Transient Flow-After-Flow Test Data: A Reservoir Management Practice
Authors: Kabir C. S. , King G. R. 
Published: December 2007

ABSTRACT
A method for analyzing transient flow-after-flow (FAF) deliverability test data from both gas and oil wells is presented. The paper describes the derivation and application of this method to several field and synthetic cases. The method solves the transient absolute open flow potential (AOFP) and average reservoir pressure (p¯) by evaluating the parameters of the Forchheimer (a and b) and the empirical backpressure (C and n) equations together with p¯. Consequently, this new method allows one to describe the stabilized deliverability equation from transient test data, given reasonable estimates of the reservoir drainage area and shape. This approach is a significant improvement over currently available methods, which require an independent, a priori knowledge of p¯ for establishing a well's AOFP, along with the need to conduct a stabilized flow segment of the test.
All the resulting formulations are flexible enough to handle the pressure, pressure-squared, and pseudopressure approach for gas wells. This methodology is not restricted to gas wells as oil wells also lend themselves to the proposed analysis procedures. For oil wells, we used the pressure approach for single-phase flow and the pressure-squared approach for two-phase flow.
In the proposed technique, a well's orientation is unimportant. For example, a horizontal well's deliverability may also be characterized using the new method. In addition, layered reservoirs may be analyzed with the proposed technique. We also show that this method can be extended to injection wells.
Synthetic data were initially used to verify the method. Field data from several gas and oil wells, including a horizontal well and gas injector, were then used to demonstrate the method's application. In all cases, the new method shows good agreement with the results obtained from conventional methods, both in terms of AOFP and p¯.
Closure Stress Calculations in Anisotropic Formations
Authors: Iverson William P.* 
Published: December 2007

ABSTRACT
The prediction of hydraulic fracture growth is controlled in part by the subsurface confining stress. Previous work has been based upon a simple relationship between vertical overburden stress and horizontal stress as a function of Poisson's ratio. Field measurements of closure stress have failed to consistently verify the relationship between vertical and horizontal stress, so that additional calibrations are required. Alternatively, consideration of an anisotropic Poisson's ratio results in a different relationship between vertical and horizontal stress. A portion of the observed difference between theoretical and calculated closure stresses is probably due to such an anisotropic effect. The azimuthal direction of induced hydraulic fracture growth is controlled by anisotropy in both tensile strength and Poisson's ratio. Field measurements of closure stress do not necessarily determine the minimum horizontal stress in anisotropic rocks. Geophysical measurements of anisotropy can greatly affect the engineering of hydraulic fracture treatments.
A Wellbore Model For Steam Injection Into Multiple Sands Through Limited-Entry Or Gravel-Pack Completions
Authors: Arthur J. E. , Hajdo L. E. , Ellison T. K. , Eggenschwiler M. E. , Chiou C. S. 
Published: December 2007

ABSTRACT
Limited-entry perforations are used to meter steam injection into separate sand intervals within the same well. The steam flow rate into a perforation varies significantly with quality. In wells with gravel-pack completions, quality variations can also affect injection rates and heat distribution profiles. Tubing tail placement in either completion method may optimize performance.
A model was developed to investigate the effects of both limited-entry and gravel-pack completions, as well as the effects of tubing tail placement, on steam quality and heat injection distribution downhole. For mass and energy outflow calculations the reservoir is divided into different layers of unique properties. Steam rates entering each layer are dependent on wellbore and reservoir properties in that layer. Limited-entry perforations may be under critical or subcritical flow, depending on the properties in the wellbore and the reservoir. When the tubing tail is placed anywhere within the pay, steam will split at the tubing tail according to the wellbore and reservoir properties. The program can handle either a constant injection rate or a constant pressure at the well head.
The model has been successfully matched to bottomhole phase velocities and pressures obtained from field surveys. The program can be used to assist in completions designs, workovers, and in the interpretation of wellbore surveys.
OffsetSteam Injection Shut-In Guidelines During Drilling Operations: South Bel ridge Field Case Study
Authors: Bert D. R. , Chiou C. S. 
Published: December 2007

Abstract
Offset steam injection wells within a certain radius are typically shut in within a certain time period before drilling an in-field (increased density or replacement) well. The basis of this practice is that the reservoir pressure will eventually decrease to a minimum value, allowing drilling to proceed without problems. A study was undertaken to develop injection shut-in guidelines which consider specific reservoir conditions such as pressure, pattern size, and steamflood maturity.
This paper highlights the causes of steamflood well control problems and presents drilling practices which can reduce potential problems. A reservoir simulation was performed to predict the injector pressure falloff response in a South Belridge field steamflood. As a result of this study, over 80 in-field wells have been successfully drilled using a shorter shut-in time and radius. The major benefit is reduced injection well downtime and production loss associated with offset drilling operations.
Pulsed Neutron Spectroscopy Logs Add Value to Steam Flood Management Process by Monitoring Oil Saturation in Kern River Field, California
Authors: Zalan Thomas A. , Henshaw Paul C. , Abels Harold P. , Owens Brian K. , Guo Dunstan S. , Salaita George N. , Mikulich Weston 
Published: December 2007

ABSTRACT
A PNS logging program was designed to evaluate the economic potential of vertical steam flood expansion and to identify bypassed oil, based on a comparison of oil saturations from a Pulsed Neutron Spectroscopy (PNS) log to conventional core in a Kern River field well. In the comparison, PNS log oil saturations agreed with those from conventional core within ±5.4 saturation units 68% of the time (log accuracy: 1 σ = 5.4). From multiple passes of the PNS log, it was found, for one effective pass at 60 feet/hour that the measurement repeats within ±5.7 saturation units 68% of the time (log precision: 1 σ = 5.7).
After the comparison of log to core, a multiwell logging program was designed to determine oil saturations for several reservoir zones above and below existing steam flood zones. The results were used to optimize patterns for future steam flooding. In addition, oil saturations were obtained for zones within the existing steam flood to determine the economic value and risk for producing bypassed oil.
For a proposed vertical expansion project, Expected Value Decision Analysis showed a benefit/cost ratio of 39/1 of running three PNS logs in the project area. The fraction of the total uncertainty associated with simulated production was reduced from 72% before to 39% after running the PNS logs. In addition, the PNS logs identified several million barrels oil in place that had not responded to conductive heating.
Determining Water Saturation in Diatomite Using Wireline Logs, Lost Hills Field, California
Authors: Bilodeau B. J. 
Published: December 2007

ABSTRACT
There is a long-held paradigm in the California oil industry that wireline log evaluation does not "work" in Monterey Formation lithologies. This study demonstrates that it is possible to calculate accurate oil saturation from wireline log data in the diatomite reservoir at Lost Hills field, California. The ability to calculate simple but accurate oil saturation is important because it allows field management teams to map pay, plan development and waterflood programs, and make estimates of reserves more accurate than those based on core information alone.
Core data from eight wells were correlated with modem resistivity and porosity logs, incorporating more than 2000 ft of reservoir section. Porosity was determined from bulk density and water saturation was determined using the Archie equation. Crossplots of corrected core oil saturation versus Archie oil saturation (1 −Sw) confirm the accuracy of the algorithm. Improvements in the accuracy and precision of the calculated oil saturation will require more detailed reservoir characterization to take into account lithologic variation.
A Fast Track to Effective Waste Minimization: Government and Industry Working Together
Authors: Sims B. C. , Savage L. L. 
Published: December 2007

Abstract
The Railroad Commission of Texas (the Commission) has been involved in regulating the oil and gas industry, including preventing pollution of land and water, since 1919. The Commission recognizes the importance of its role with respect to waste minimization. Government can provide a good avenue for communication between members of all segments of the oil and gas industry. Also, it is in the government's interest for the oil and gas industry to be successful in its waste minimization efforts - successful waste minimization can increase industry ability to comply with regulations.
The Commission's Waste Minimization Program was formally launched in 1992. In May, 1993, the Commission prepared and distributed a survey to gather information on industry waste minimization practices and opinions regarding incentives and barriers. Survey participants and other interested persons attended a follow-up Pollution Prevention Workshop to express their ideas on how the Commission could effectively assist the industry in its waste minimization efforts. The Commission has incorporated many of these ideas in its Waste Minimization Program.
The Commission has since implemented several activities to promote oil and gas waste minimization. These include: 1) providing operators access to a technology transfer database that contains technical papers and articles addressing waste minimization in oil and gas operations; 2) publishing a waste minimization manual for distribution to oil and gas operators; 3) presenting a waste minimization workshop to operators and Commission staff at locations statewide; 4) publishing the "Waste Minimization Program Newsletter" to complement the other program activities; and 5) offering on-site visits to assist operators in assessing operations and developing waste minimization plans. Also, we are continuing to look for possible changes in existing rules and procedures to eliminate barriers to, and create positive incentives for, waste minimization efforts.
The oil and gas industry has responded enthusiastically to the Waste Minimization Program and provided numerous case studies of successful waste minimization efforts and other waste minimization information. This paper provides several examples of the case studies that have been provided by industry participants in the program.
Business Approach to Waste Management
Authors: Bradford R. A. 
Published: December 2007

Abstract
Today, resources of the oil and gas industry are pulled in many directions. It takes a major effort to manage the various priorities demanding attention. A company's effectiveness in balancing priorities determines whether it survives. An area increasing in its demand for resources is waste minimization. In order to minimize waste and reduce pollution possibilities, activities having the potential to cause environmental events must be managed in a conscientious, businesslike manner. The integration of environmental considerations into the business plan of the company or business unit will facilitate proper resource allocation to this area of the oil and gas business.
In this paper, policies, objectives and organization are reviewed as to how they are used to develop practical programs to allow field application of these business related factors. Monitoring, measurement and auditing are viewed as methods to sample the condition of the environmental elements. This condition "snap shot" provides a baseline for redirecting efforts to continuously improve the environmental management.
Gas Industry-Related Exploration and Production Waste "Demographics" Utilizing GIS
Authors: Daly Daniel J. , Stoa Rodney S. , Bassingthwaite Scott A. , Sorensen James A. , Charlton David S. , Mesing George , Evans James M. 
Published: December 2007

Abstract
Exploration and production (E&P) waste "demographics," i.e., an assessment of the occurrence and types of wastes, waste generation sites, management practices, and costs, has been completed for natural gas-related produced water and drilling wastes in the United States for the year 1990. Information acquired from purchased data sets, a review of the literature, and a telephone survey of over 300 regulatory and industry personnel was assessed at the geologic province, state, state/geologic province, and county level, with a focus on the onshore lower 48 United States.
For the lower 48 onshore states in 1990, results indicate that gas-related activities generated over 389 million barrels (MMbbl) of produced water and nearly 44 MMbbl of drilling waste. Together, these gas-related wastes represented less than 4% of the combined total of those waste types generated for both gas- and oil-related activities. Injection dominated disposal for produced water, but discharge was important in the Gulf Coast Basin and for select coal bed methane waters. Off-site management of liquids, mainly by injection, dominated for drilling wastes. However, nearly a third of the holes, which were drilled with air rotary systems, produced relatively small volumes of solids-dominated wastes, managed mainly on-site.
Delineation Of Biological Impact and Recovery of Selected Produced Water Discharges in Inshore Louisiana
Authors: Mulino Maureen M. , Rayle Michael F. , Francis John C. , Poirrier Michael A. 
Published: December 2007

Abstract
The benthos data presented are the results of sampling areas around the Delacroix Island Tank Battery #1 produced water discharge prior to and after termination. Data show recovery of the numbers of species and individuals at the discharge site six months after the termination of the discharge.
Discrimination of Ion Toxicity in Six Produced Waters Using the Freshwater Salinity Toxicity Relationships and TIE Procedures
Authors: Tietge J. E. , Hockett J. R. , Evans J. M. 
Published: December 2007

Abstract
Research to characterize the toxicity of common ions to freshwater organisms resulted in the development of predictive toxicity models (FW STR) for three freshwater species (Ceriodaphnia dubia, Pimephales promelas, and Daphnia magna). The FW STR models, derived from acute toxicity data, focused on the toxicity of seven common ions. These predictive models were used in conjuntion with Phase I TIE procedures to evaluate the contribution of common ion toxicity in six produced water samples ranging in total salinity from 1.7 to 58.1 g/L. Initial toxicities of all six samples were compared to the model predictions. Four produced water samples were found to have toxicity due to common ion concentrations only. Two samples were found to exhibit more toxicity than expected from ion concentrations alone. These samples were subjected to Phase I TIE procedures. Toxicities were reduced by specific Phase I TIE manipulations to those predicted by the FW STR models. Mock effluents were used to verify the results. The combination of the FW STR models with Phase I TIE procedures successfully quantified the toxicity due to common ions.
Shale Oil Survival in Underground Retorting By Combustion
Authors: Prasad R.K. , Thomas G.W. 
Published: December 2007

Abstract
A simplified mathematical model is developed to determine the amount of oil that survives passage to a hot fracture boundary in an underground retorting process in oil shale. Combustion at or near a fractured surface, heat conduction, oxygen diffusion, reaction of oil and oxygen, and perpendicular oil flow by diffusion and perpendicular oil flow by diffusion and convection toward the hot boundary are considered.
Appropriate assumptions are employed to arrive at upper bounds on the predicted recovery. Significant amounts of oil production are unlikely when the fracture temperature approaches 2000 degrees F. However, if the temperature is 1200 degrees F. or lower, the calculated upper bound is 64%. When more realistic assumptions are invoked, the computed results indicate no oil recovery.
The effects of oil migration velocity and the kinetic parameters were studied. Predicted recoveries were highly sensitive to the activation energy for temperatures below 2000 degrees F
We conclude that underground combustion in oil shale employing hydraulically or electrically created fractures apparently is not technically feasible unless appropriate means of reducing temperatures are employed. It appears that massive rock breakage is necessary to achieve substantial amounts of oil production.
Introduction
The possibility of underground retorting of oil shale appears attractive since mining, crushing, and spent shale disposal are not involved. However, it is necessary to induce a flow path in the rock since oil shale usually has no primary permeability and porosity (vugular porosity excluded). To porosity (vugular porosity excluded). To accomplish this, hydraulic fracturing, nuclear detonation, and electro-fracturing have been suggested. A number of thermal processes, such as hot fluid injection, forward combustion, reverse combustion, and conduction heating, can presumably be conducted within a single fracture presumably be conducted within a single fracture or system of fractures. Other methods have been proposed which combine two or more of these basic processes.
The success of any of the above processes will necessarily hinge on whether or not sufficient quantities of the liquid product can be recovered. In most cases, the system of fractures created in the shale must serve as the flow path for the produced as well as the injected fluids. Some or all of the produced fluids will frequently pass through high temperature zones to reach the fractures. To make intelligent performance predictions, it is important to know if the residence time and temperature levels will result in severe reduction in oil yield by destructive distillation and oil burning.