bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Lithology Independent through Casing Porosity and Water Saturation Model LIPS
Authors: Oraby M. E. 
Published: December 2007

Abstract
The demand for low cost but reliable technology in drilling, logging and production is always and will continue to be one of the most important issues facing the oil industry. In addition, increasing production through field management and evaluating bypassed reserves in existing fields using lower cost but reliable technology is a primary objective of any oil company. From this motivation, a through casing log interpretation technology for assessing formation evaluation and identifying existing field opportunities would offer a low cost and risk option for many operations.
In this paper, a through casing log interpretation technology termed Lithology Independent Porosity and water Saturation or, LIPS, is presented. LIPS is a technology that is suitable for infill drilling programs, fluid monitoring for field management and in analyzing old fields that do not have enough or modern data. LIPS requires three measurements to provide porosity, water saturation and the locations of the heavy minerals that may be the source for net pay determination. These three measurements can be obtained using the three common cased hole logs; a thermal Compensated Neutron porosity Log or CNL, an epithermal neutron porosity and a Pulsed Neutron Capture log PNC type tool, e.g., TDT, for formation absorption cross section.
For porosity, LIPS considers any formation as a composite of two major components, the pore space and the matrix. LIPS deals with the matrix as a black box where it calculates its overall controlling parameters. The formation porosity is chosen when the calculated parameters using two different techniques converge.
For water saturation, LIPS uses data that has been discarded by the industry, the thermal neutron detectors counting rates of the thermal neutron tool. These counting rates are functions of the formation water salinity and the matrix absorption cross section. LIPS uses the two thermal neutron counting rates, near and far, of the thermal neutron tool CNL along with the formation absorption log to produce three equations in three unknowns. The three unknowns are water saturation, water salinity and matrix absorption. Therefore, LIPS does not require prior information about matrix absorption or the formation water salinity which gives LIPS superiority to many of the existing water saturation models.
LIPS has been tested in a variety of reservoirs from all over the world. Comparisons between LIPS porosity and water saturation and core porosity and low invasion water saturation core are presented. Also, the environmental effects on LIPS interpretations, e.g., invasion, are discussed.
Optimizing Water Injection Profiles with Oxygen Activation Logging
Authors: Schnorr D. R. 
Published: December 2007

Abstract
Impulse oxygen activation logging was successfully introduced in Alaska in 1990. It was immediately used to determine water injection profiles behind tubing in the annulus between the tubing and casing. In the past, this type of well completion was difficult, if not impossible, to evaluate with the techniques that were available before the introduction of the impulse oxygen activation logging method. The impulse oxygen activation technique uses the pulse neutron tool to activate the oxygen in the water so that the water flow profile can be determined. Since neutrons are used to activate the oxygen in the water, the metal in the tubing does not stop the activation of oxygen in the water when it is behind tubing. Impulse oxygen activation logging is also used to identify water producing zones in producing wells, and whether there is water flowing through channels in the cement behind casing.
This new method of using impulse oxygen activation provides the capability to trace water flow over a wide range of water injection and production rates. Using a series of station measurements, it is possible to measure water velocities from less that two ft/min (0.01 m/s) to more than 400 ft/min (2.0 m/s) with modified pulse neutron tools. The impulse oxygen activation method also has the ability to measure two different water velocities in the same direction at the same time. This is possible because only a small amount of water is activated by the impulse oxygen activation. The activated water then flows past three different detectors spaced at 2-ft, 6-ft, and 20-ft at its different velocities. Knowing the cross sectional areas of the different flow paths, water flow rates from l0 to over 10,000 BWPD are directly calculated. Since the pulse neutron tool has no moving parts, it cannot be plugged with scale or particles suspended in the injected water such as is the case with spinner type tools.
This measurement has significantly reduced the traditional uncertainties associated with the economics of attempting to shut-in high watercut intervals. With these advances the emphasis can now turn to assessing improved modification techniques. The final result will be increased oil recovery and reduced water cycling.
Laboratory and Field Evaluation of Organosilane as a Formation Fines Stabilizer
Authors: Stanley F. O. , Ali S. A. , Boles J. L. 
Published: December 2007

Abstract
Formation damage associated with fines migration has often contributed to rapid production declines and short-lived stimulation successes. Although clay migration and stabilization have been discussed in various papers through the years, the non-clay siliceous fines stabilization has received little attention. A recently developed fines stabilizing method is utilized to reduce or prevent the migration of both clay and non-clay siliceous fines. This method utilizes an organosilane additive which reacts in situ to stabilize potentially mobile siliceous fines. This paper describes the use of and the mechanism by which the organosilane additive stabilizes fines. The laboratory data and field case histories further discuss the beneficial effects of employing organosilane as a fines stabilizing agent.
A New Long Stroke Pumping Unit with High Speed
Authors: Wang D. F. , Cui X. M. , Gao G. Y. , Huang Z. Z. , Hu B. Z. 
Published: December 2007

Abstract
‘Qing You’ long stroke pumping unit is a high velocity pumping unit. It is designed to achieve a large pump output of more than 200 m3/d with the diameter of rod pump less than 70mm, and the aunulus test can be conducted in the course of production.
Based on the analyzing of some pumping unit commonly used in oil field and the relationships between acceleration and various parameters, in this paper, the design considerations was presented. The maximum velocity υm of the new developed pumping unit is about 40% higher than the recommendation for υm of common pumping unit, and its maximum acceleration αm is in the range of that of the conventional ones.
Beam Pump Balancing Based on Motor Power Utilization
Authors: McCoy J. N. , Ott R. E. , Podio A. L. , Collier Forrest , Becker Dieter 
Published: December 2007

ABSTRACT
Recent application of a portable computer-based instantaneous power meter which is easily connected to a beam pump's switch box, has made it possible to study in detail the effect of counterbalancing on electrical consumption and operating cost.
This paper describes the measurement system as well as its application to determine the power usage per pump stroke and the gear reducer torque. A simple algorithm is presented for the determination of the counterweight adjustment required to modify the peak torque or the power use.
The results of accurately monitored field tests for a variety of beam pumps and well depths are presented in detail. The measurements indicate that unit balancing based on instantaneous power, yields results similar to those obtained from torque derived from dynamometer measurements using a horseshoe type load transducer. The ease of installation of the power probes compared to installation of the dynamometer makes this the preferred method for most beam pumping systems powered by electrical motors.
Using Automation for Optimizing Production Fields
Authors: Outomuro M. Vázquez 
Published: December 2007

ABSTRACT
Through automation it is possible to remotely monitor and control production fields seeking to guarantee maximum production, minimum operating cost, and extending the useful life of the equipment.
The objective of the Automation scheme shown in this work consists of integrating all the steps needed to optimize a well through advanced control techniques that would comprehend three modules; a) Automatic Acquisition of Data (Field Instrumentation and Acquisition Systems); b) Real Time Data Processing and Issuing of recommendations (here we have Mathematical Modeling, Real Time Expert Systems, Neural Networks, Genetic Algorithms, Simulation Models); c) Control over field variables, allowing the application of the recommendations obtained in b)
An Approach to the Optimum Design of Sucker-Rod Pumping Systems
Authors: Han Dianli , Wiggins Michael L. , Menzie Donald E. 
Published: December 2007

ABSTRACT
Sucker-rod pumping system design is often a trial and error process. Many simplifying assumptions are used which may not be consistent with the well conditions. This paper presents a new methodology for the optimum design of pumping unit systems.
In this approach, plunger diameter, polished rod stroke length, pumping speed and pump intake pressure are chosen as basic design variables. Production rate and rod string taper are determined by an iteration algorithm which systematically couples well inflow performance and vertical flow effects into the design process. Polished rod load, peak gear box torque, polished rod horse power and counterbalance effect are also determined at the end of the iteration calculation. Different design objective functions can be used to rate the pumping modes. Thus, the optimum design of pumping unit systems becomes a matter of solving for the combination of the four basic design variables which maximize or minimize an objective function within the limitations of available equipment by a mathematical programming method.
Single-Trip Completion Concept Replaces Multiple Packers and Sliding Sleeves in Selective Multi-Zone Production and Stimulation Operations
Authors: Coon Robert , Murray Doug 
Published: December 2007

ABSTRACT
In conventional multi-zone completion operations, selective production and/or stimulation requirements are accomplished by opening and closing sliding sleeves in each producing zone. This completion method requires at least one trip per zone as well as substantial amounts of equipment in the well. An alternative method that is being field tested will move the internal control of the well from the tubing string to the casing. This eliminates equipment from inside the well and reduces the number of trips required from one per zone to a single trip for the entire well. This paper describes the single-trip completion concept, primarily for horizontal wells, as well as the new technology that has been developed to support it.
Transient Aspects of Unloading Oil and Gas Wells With Coiled Tubing
Authors: Gu H. 
Published: December 2007

ABSTRACT
Unloading oil and gas wells with coiled tubing (CT) conveyed nitrogen circulation is a transient process in which the original heavier fluid in a wellbore is displaced by nitrogen and lighter reservoir fluid. The transient aspects need to be considered when determining nitrogen volume and operation time for unloading a well. A computer wellbore simulator has been developed and used to study the transient effects. The simulator includes transient multiphase mass transport and takes into account the different fluids in the wellbore and from the reservoir. The simulator also includes the gas rise in the wellbore liquid below the CT and can be used for gas well unloading. The transient results of oil and gas well unloading are presented. The effects of CT size and depth, workover fluid, and nitrogen rate and volume on unloading are discussed. Unlike continuous gas lift, the total gas volume needed and the operation time in an unloading process can only be determined and optimized based on a transient analysis.
Current Use of Limited-Entry Hydraulic Fracturing in the Codell/Niobrara Formations—DJ Basin
Authors: Eberhard M. J. , Schlosser D. E. 
Published: December 2007

Abstract
In the last several years, limited-entry perforating has been used for hydraulically fracturing the Codell and Niobrara formations in the Denver-Julesburg (DJ) Basin. Limited-entry perforating reduces stimulation costs with no apparent effect on production.
Several papers have presented guidelines for designing a limited-entry treatment. A primary concern for treating multiple intervals is to ensure that both zones receive the necessary treatment. Currently, some operators simply ratio the number of perforations in each interval to the volume of treatment required for each interval. To ensure that both zones are being treated, a minimum pressure drop of 700 to 1,000 psi is usually used for limited-entry design. Changes in the perforation discharge coefficient and diameter during the treatment, combined with changes in the net treating pressure, affect the perforation pressure drop calculation. To determine the actual pressure drop across the perforations, designers use a real-time spreadsheet calculation.
This paper reviews limited-entry treatments pumped in 34 wells that verify spreadsheet calculations. Changes in the perforation discharge coefficient and diameter will be presented, as well as the effect of proppant concentration and velocity through the perforation. The current spreadsheet calculation used on location to calculate the pressure drop across the perforations is also discussed.
Impact of Trapping of Residual Oil by Mobile Water on Recovery Performance Miscible Enhanced Oil Recovery Processes
Authors: Rampersad P. R. , Ogbe D. O. , Kamath V. A. , Islam R. 
Published: December 2007

ABSTRACT
In this paper we examine how residual oil trapping by mobile water affects the recovery performance of miscible EOR processes. The objectives of the study are (1) to develop a multiphase, numerical model to investigate factors affecting water-blocking and the release of oil from dendritic states; (2) to evaluate performance of miscible processes and forecast displacement efficiency and recovery under a variety of operating conditions, and (3) to determine the "optimum" water-solvent ratio to be used in a miscible Water-Alternate-Gas (WAG) process. Using the multiphase flow model, we considered the oleic phase as two parts, a mobile phase and a trapped phase, and studied the effects of capillary forces, solvent viscosity, fraction of trapped oil, dispersion and mass transfer coefficients on recovery performance. Guidelines for determining the optimum water-solvent ratio to be used in a miscible WAG process are discussed.
Fracturing from Highly Deviated and Horizontal Wells: Numerical Analysis of Non-planar Fracture Propagation
Authors: Olson Jon E. 
Published: December 2007

ABSTRACT
Fracturing from horizontal and highly deviated wells can often result in complex, non-planar fracture geometry. A two-dimensional model was developed to analyze the effects of non-planar fracture propagation for different in situ boundary conditions and hydraulic fracturing parameters. Numerical simulations show that curving fracture geometry reduces created fracture length compared to a planar fracture and causes a fracture width restriction at the wellbore. Reduction in fracture length can reduce expected well stimulation effects and jeopardize well economics. Near-wellbore width restrictions increase fracture treating pressure and may cause wellbore screen-out during the proppant stages of a fracturing treatment. The negative impact of non-planar geometry can be mitigated with short perforated intervals, high viscosity fracturing fluids, proper wellbore alignment and pre-pad proppant slugs for near-wellbore erosion.
Forecasting Long-Term Gas Production of Dewatered Coal Seams and Fractured Gas Shales
Authors: Spivey J. P. , Semmelbeck M. E. 
Published: December 2007

ABSTRACT
A procedure is presented which allows forecasting long range performance of dewatered coal and fractured gas shale reservoirs having nonlinear adsorption isotherms, using constant pressure solutions to the flow equation for slightly compressible liquids. A correlation is presented to show the range of applicability of this procedure.
Computational Modeling of Multi-Layered Reservoirs With Unequal Initial Pressures: Development of a New Pre-Production Well Test
Authors: Aly Ahmed , Lee W. J. 
Published: December 2007

Abstract
The objective of this paper is to present a description and verification of a new semi-analytical simulator used to model the wellbore performance of multi-layered reservoirs with unequal initial pressures. The semi-analytical simulator proved to be faster than a conventional three-dimensional, finite-difference commercial simulator. Also the amount of information needed to run the model is much reduced. The semi-analytical simulator allows each layer to have different layer properties, different boundary conditions, and different initial pressures.
The semi-analytical simulator was used to model the reservoir performance for two, three and five layered reservoir cases from the literature. The results were verified by comparing them to the results generated using a finite-difference simulator. The agreement was excellent for all the tested cases.
Also, we developed a new well test, the Pre-Production Well-test or PPWT. The PPWT is performed early in the life of a reservoir when the information is most needed for planning production schedules and making economic decisions concerning the life of the wells. Pre-production is the period after completion but before production of the well. Immediately after perforation, we position a pressure gauge above the top perforation to measure the pressure performance from the total system (in two or three layer systems). Cross flow in the wellbore from one layer to another will cause the pressure signal. The cross flow is due to the differential pressure between the layers. One important advantage of the pre-production well test is that there is no production on surface during the test. Thus, the environmental impact caused by flaring oil or gas during a conventional well test is alleviated.
We developed the "Derivative Extreme Method" (DEM) for the analysis of wellbore pressures measured during the pre-production well test. The DEM determines layer properties form single pressure profile; no rate measurements are required. The DEM requires that the wellbore pressure be measured until one boundary is felt (i.e., the late-transient region must be reached).
Comparison of Single and Multi-Facies Variograms of Newcastle Sandstone: Measures for the Distribution of Barriers to Flow
Authors: Lund H- J. , Ates Harun , Kasap Ekvem , Tillman R. W. 
Published: December 2007

Abstract
The objective of this paper is to quantify the distribution of potential flow units within valley-fill outcrop deposits by utilizing geostatistical parameters, especially variograms. The Newcastle (Muddy) Sandstone, which is a prolific producer in the Powder River Basin of Wyoming, is the subject of our outcrop reservoir characterization analysis which compares the relationships of detailed geological (sedimentological) interpretations of facies, detailed in situ permeability measurements, and outcrop gamma-ray log surveys. Much of the Newcastle (Muddy) Sandstone, which crops out near Newcastle, Wyoming was deposited by tidal currents backfilling valleys formed during a Lower Cretaceous sea level drop. The Skull Creek Shales which underlies and is lateral to the Newcastle sandstone forms lateral and bottom seals.
We concurrently measured the permeabilities and gamma-ray responses of beds on three vertical transects with a grid extending normal to the bedding and three lateral grids which are as nearly parallel to the bedding as possible. We generated geostatistical parameters from these data sets. In all cases, Dykstra-Parsons coefficients are in the neighborhood of 0.35 for the single-unit data and above 0.8 for the multi-unit measurements. Coefficients of variation are below 0.5 for single units and above 0.8 for multi-unit data sets.
Multi-unit variograms show hole effect and often strong trend, while single unit variograms always indicate nugget effect with a weak trend. The correlation between the plots generated from measured permeability and gamma-ray responses are impressive. Permeability and gamma-ray variograms are similar. The variograms in the vertical and horizontal directions are quite different. Therefore, they cannot substitute one for another. We also concluded that relative semi-variograms are a better way of presenting formation heterogeneities. We observed that abrupt variations in outcrop gamma-ray values are also excellent indicators of bed contacts.
We used the generated geostatistical parameters in a simulated annealing program to predict permeabilities of lateral profile A, and concluded that variogram, mean and standard deviation are required but not sufficient parameters to predict the distribution of reservoir heterogeneity.
Interpretation of Steam Drive Pilots in the Belridge Diatomite
Authors: Johnston R. M. , Shahin G. T. 
Published: December 2007

ABSTRACT
The South Belridge Diatomite Field contains more than 2.5 billion barrels of oil-in-place. Current primary and waterflood development are estimated to recover only a small fraction of this oil. Despite it’s low permeability, the diatomite may be a good candidate for the steam drive process, due to its thick oil column (1,000 ft), high porosity (50% to 65%), and high oil saturation (up to 70%).1 With these attributes, thermal expansion and decreased viscosity of reservoir fluids accelerate oil production, without significant heat loss to cap and base rock.
Steam drive pilot operations have been conducted at South Belridge since 1986. This paper discusses the pilot projects and the 15-acre steam drive full-scale project currently being installed.