bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pressure Transient Behavior of Non-Newtonian/Newtonian Fluid Composite Systems in Porous Media With a Finite Conductivity Vertical Fracture
Authors: Ertekin T. , Cicek O. , Adequmi M. A. , Daud M. E. 
Published: December 2007

ABSTRACT
This study simulates the pressure transient behavior of flow of Newtonian/Newtonian and non-Newtonian /Newtonian fluid composite systems in porous media with a finite-conductivity vertical fracture. The main objective of this study is to determine the location of the flood front, reservoir rock and fluid properties and fracture parameters via history matching of the test data. It is assumed that the injected fluid front propagates in the form of an ellipse whose focal length is equivalent to the fracture length, and single-phase flow conditions exist behind and ahead of the flood front. The viscosity of the non-Newtonian fluid in the flooded region was formulated as a function of the average flow rate. Both the injected and the reservoir fluids are treated as being slightly compressible.
It is assumed that flow inside the matrix is two-dimensional, and one-dimensional inside the fracture. Two different fluid flow equations, one for the matrix and the other for the fracture, are used to describe the single-phase flow conditions. The equations are coupled through a fluid loss term from the fracture into the matrix and/or from the matrix into the fracture. Four different fluid loss models in three different flow geometries (elliptical, linear and radial) are considered. These two non-linear equations are linearized numerically, and the resulting two systems of linear equations are solved simultaneously using the alternating direction implicit procedure.
Extensive testing and validation of this generalized formulation was conducted by using it to study nine special cases previously reported in the literature. A parametric investigation was conducted using dimensionless groups such as non-Newtonian power-law fluid exponent, fracture conductivity, elliptical interface location and mobility and diffusivity ratio. The results indicate that as the power-law index increases, the dimensionless bottomhole pressure increases for a given injection rate. In cases of mobility ratios greater than unity, smaller elliptical interface locations, which represent initial amounts of injected fluid in the reservoir, give greater dimensionless bottomhole pressures, and in cases of mobility ratios less than unity, smaller elliptical interface locations give smaller dimensionless bottomhole pressures. Greater mobility ratios yield greater dimensionless bottomhole pressures; increasing dimensionless fracture conductivities result in decreased bottomhole dimensionless pressures. It is observed that this decrease is not significant for dimensionless conductivities larger than five hundred.
Predicting Gas Well Performance Under Altered Conditions
Authors: Aminian K. , Ameri S. , Beg N. , Yost A. B. 
Published: December 2007

ABSTRACT
Forecasting production rates from gas wells has always been of considerable importance to the natural gas industry. The conventional method of predicting the performance of gas reservoirs requires data which are often unavailable. This is particularly the case when dealing with low permeability gas reservoirs. In the absence of complete reservoir data, the production decline type curves are employed to predict the future rates utilizing production history. Generally, the production decline type curves are generated based on assumption that the operating and reservoir conditions which affected gas production in the past will remain unchanged. However, there are many instances when it is necessary to forecast the production rates under conditions which are not similar to those of the past. Typical examples of such cases are: (a) changes encountered in well spacing due to developmental drilling programs and (b) backpressure changes which occur due to compressor installations. This paper introduces a series of production decline type curves and relative methodologies which can be utilized to forecast gas production when the conditions are altered. A gas reservoir model has been utilized to simulate gas production to study the effects of changes relative to reservoir and operating conditions. The model takes into account many factors such as the non-Darcy flow effects, skin factor, and pressure dependent gas properties. The results have been utilized to develop techniques (for type curve applications) to forecast production under different reservoir and operating conditions.
Data Base for Eastern Gas-Bearing Formations: Development and Application
Authors: Ameri S. , Aminian K. , Yost A. B. 
Published: December 2007

ABSTRACT
The Appalachian Basin contains a number of low permeability formations which have produced natural gas for many years. The lack of reliable data/information pertaining to parameters controlling production of natural gas from such low permeability (tight) gas bearing formations has hindered their continuous economic development. The data that have been available usually consisted of isolated data points held within the company files without a mechanism for comparison with other similar formation(s) in the Appalachian Basin. This has effectively prohibited the development of any kind of statistically base from which one might infer the production mechanism, predict performance, determine the responsiveness of formations to stimulation treatments, and delineate the high potential areas for future development.
The overall goal of this study is directed towards answering some of the questions needed to help the eastern low permeability formations become viable candidates for future development. This research project endeavors to solve the problem, at least for a subset of the tight gas bearing formations consisting of Big Injun, Berea, Benson, Oriskany, Big Six and Tuscarora that exist in the Appalachian Basin.
The research objectives have been achieved through:
Development of a Database through collection, interpretation, and compilation of data relative to completion, production, and stimulation on the eastern tight gas formations so that a good research foundation can be established. Analysis of the data so that the key parameters affecting gas production can be identified and quantified.
It should be noted that the Database contains data on over 1200 wells in Kentucky, New York, Ohio, Pennsylvania, Virginia, and West Virginia. The information has been collected from a variety of sources including many gas companies.
The Database can be utilized to identify and evaluate a range of lithological, reservoir, and treatment parameters which control the production of natural gas from the eastern tight gas formations. The utilization of the Database and its applications relative to identification and evaluation of the potential areas for future economic development are discussed in this paper.
Accurate Formulas for Calculating the Water Influx Superposition Integral
Authors: Vogt J. P. , Wang B. 
Published: December 2007

ABSTRACT
For quickly responding aquifers, the widely used step pressure (SP) formula for evaluating the water influx superposition integral is inaccurate as it is normally employed. Using the SP formula in the material-balance-with-water-influx equation causes it in turn to give inaccurate results. A totally general, linear pressure (LP) formula is introduced that more precisely evaluates the water influx superposition integral and leads to the following advantages when used in the material balance equation: (1) the. original gas or oil in place (OGIP/OOIP) and aquifer parameters can be determined earlier in a reservoir's life, (2) reservoir pressure can be predicted more accurately once the OGIP/OOIP and aquifer parameters are known, and (3) OGIP/OOIP and equivalent aquifer parameters can be determined for reservoirs with a variety of drive mechanisms-including shale water influx and rock compressibility – without knowing what the actual drive mechanism is. It is also pointed out that a computationally efficient linear pressure recursion (LPR) formula developed by Leung for reservoir simulators has the same accuracy as the LP formula derived in this paper.
Determination of Volume, Type, and Distribution Modes of Clay Minerals from Well Logging Data
Authors: Fertl Walter H. , Chilingar George V. 
Published: December 2007

ABSTRACT
Typical shaly clastic reservoir rocks and/or shale intervals frequently contain varying amounts of different clay minerals. Most common clay minerals exhibit significant differences in their basic properties, including chemical composition, matrix density (g/cc), photoelectric cross section (Pe, barns/electron), hydrogen index (HI), cation exchange capacity (CEC, meq/lOOg), potassium (percent), uranium (ppm), and thorium (ppm). These different properties and associated interpretive models allow the identification and quantitative evaluation of the major clay mineral groups such as smectite, illite, kaolinite, and chlorite via geophysical well log responses.
Based on density, neutron, and natural gamma ray spectral data, two important formation parameters, clay density (ρcl) and neutron response to 100% clay (Ncl), can be determined at every depth level over the computed interval of interest. No average clay property values from adjacent shale formations are required as input. Hence, the constraints inherent to other techniques, e.g., the assumption that clay properties in the clastic reservoir and adjacent shales are identical, do not apply.
Having determined the two critical clay parameters, ρcl and Nd, the clay volume (Vd) is calculated simultaneously from both the potassium and thorium values. This Vd is essentially independent of the clay types. These three parameters (ρcl, Nd, Vd) then allow for the calculation of two important reservoir parameters at each depth level, namely the cation exchange capacity (CEC) and the hydrogen index (HI). The resulting CEC and HI values then define the types of clay minerals present. On a CEC versus HI crossplot, the smectite (montmorillonite), illite, and kaolinite/chlorite are grouped at three separate, clearly defined positions.
Recently developed interpretive refinements incorporate the photoelectric cross section value, Pe, which also allows quantitative differentiation of kaolinite and chlorite. Hence, all four major clay mineral groups (smectite, illite, kaolinite, chlorite) can be evaluated via modern logging measurements.
Furthermore, it is well known that the type of clay mineral distribution in a reservoir rock significantly affects the effective reservoir porosity, effective water saturation, permeability, and hence, intervalproducibility. Different clay mineral distributions, such as clay dispersion, clay lamination or structural clay, will affect effective reservoir porosity (ϕc) and permeability in a drastically different manner. These different clay distribution modes also can be determined from the above mentioned well logs.
Several field examples illustrate these concepts as applied to well completion, formation damage, and detailed clastic reservoir characteristics.
Iron Control Additives for Limestone and Sandstone Acidizing of Sweet and Sour Wells
Authors: Hall B. E. , Dill W. R. 
Published: December 2007

ABSTRACT
Iron precipitation has been recognized as a significant problem in acidizing operations for over 30 years. Deposits of iron compounds in tubulars combined with iron compounds in the formation determine the amount of iron dissolved by the acid and therefore, the severity of the iron problem. Data from the analysis of recovered acid on previous jobs canbe used to predict the concentration of iron that may need to be sequestered on future jobs.
Iron sequestering additives may present compatibility problems. Specific types of compatibility problems may be encountered when acidizing limestone formations with HCl, while other compatibility problems may be encountered when acidizing sandstone formation with HC1-HF blends.
Iron sequestering additives may lose effectiveness because of degradation. Degradation properties of less stable additives are discussed. The iron sequestering additives currently used are described and their effectiveness is compared using laboratory test data.
Iron sequestering in the presence of sulfides present unique problems which are explained. A system for sequestering iron in the presence of sulfides is described. Job descriptions and results from acidizing operations are presented.
Reduction Feasibility of Itabirite Mud Abrasion
Authors: Bizanti M. S. , Moonesan A. , Caruthers R. M. 
Published: December 2007

ABSTRACT
Barite consumption in the United States is a direct result of the need for weighted muds in oil and gas wells drilled. Barite demand in the petroleum industry is projected to increase from 2.65 million tons in 1983 to 5.0 million tons in the year 2000. The United States reserves of barite, estimated at 30 million tons, are not adequate to fill the projected cumulative demand of about 60 million tons by the year 2000.
This paper evaluates the benefits and problems associated with itabirite (micaceous hematite) as a weighting material in water-base muds. A laboratory investigation compared fresh water samples of barite and itabirite, and the effect of addition Kelzan XCD polymer. Three different ranges of particle size of itabirite were selected for the tests. Particle sizes between 74 and 125 microns, between 44 and 74 microns, and smaller than 44 microns were used. Thirty-minute abrasion tests were conducted with a modified Hamilton Beach Blender at 9800,11200,12570, and 14350 rpm.
Rheological properties, filtration properties, and abrasiveness were studied and analyzed. Itabirite exhibited better rheological characteristics than did barite. Itabirite could increase penetration rate since a lower solids content can be used to obtain proper weight. Itabirite did not exhibit good filtration properties and was more abrasive; however, the feasibility of using itabirite as a weighting material was enhanced with a finer particle size distribution and by use of a determined amount of Kelzan XCD polymer to control filtration and to act as a coating agent to lower the abrasiveness.
Use of Low-Density, Gravel-Pack Material Improves Placement Efficiency
Authors: Hudson T. E. , Martin J. W. 
Published: December 2007

ABSTRACT
The success of a gravel-pack completion depends on placement of gravel in the perforation tunnel area and the screen-casing annulus. Wellbore deviation is one of the predominant factors affecting gravel placement. As wellbore deviation increases, the gravitational forces and carrier fluid limitations may result in gravel settling (duning) and an incomplete packing of much of the perforation tunnel area, as well as a premature screenout of the screen-casing annulus.
A completion technique is introduced that eliminates problems associated with gravel settling. The technique uses buoyancy forces to counter the gravitational forces on the gravel particulate. Particulate settling is minimized by decreasing the ratio of the particulate density (Dp) to the base fluid density (Dc). Verification of the concept includes test results from a gravel-pack model. The model is 18 ft long with an inside diameter (ID) of 6.2 in., a screen and blank pipe size of 2-7/8 in., and a working pressure of 1,000 psi. The blank pipe length is 6 ft and the screen length is 12 ft. There are 20 perforations that include a chamber to simulate a void space behind the casing.
Test results include gravel-pack efficiency for variations in base fluid properties, wellbore deviation up to 90° (horizontal) and particulate density/ base fluid density ratios (Dp/Dc) from 2.65:1 to 0.8:1. Recommendations for a treatment technique and low-density particulate specifications also are included.
Diamond-Enhanced Hammer Bits Reduce Cost per Foot in the Arkoma and Appalachian Basins
Authors: Reinsvold C. H. , Clement J. , Oliver M. , Witt C. , Crockett J. 
Published: December 2007

Abstract
Polycrystalline diamond technology and down-hole hammer drilling have been combined to create a new type of bit. This bit, the diamond enhanced hammer bit, features diamond coated tungsten carbide inserts for improved cutting structure wear resistance. By improving bit life and increasing penetration rates, these bits have been able to reduce cost per foot in the Arkoma and Appalachian Basins.
Separating Bit and Lithology Effects from Drilling Mechanics Data
Authors: Falconer I. G. , Burgess T. M. , Sheppard M. C. 
Published: December 2007

Abstract
Most real time drilling interpretation is performed using some sort of normalized rate of penetration to infer changes in lithology and diagnose the condition of the bit. This frequently leads to ambiguous or confusing results because it is impossible to separate all bit effects from lithology effects with only one measurement. This paper shows how a second measurement, downhole torque, can be used with rate of penetration to confidently separate the bit effects from the lithology effects when drilling with milled tooth or PDC bits.
Simple drilling equations for rate of penetration and bit torque are derived and compared with well known formulae. These lead to simple "quicklook" interpretations which can be made at the wellsite with a hand calculator. A detailed analysis can be performed on a wellsite computer.
Many field case studies were made to examine the effects of lithology changes on the drilling response of milled tooth and PDC bits. A few of the studies are presented. The results indicate that:
changes in bit torque can be used to broadly classify the lithology into three categories, namely: porous, argillaceous (shaly), and tight, corresponding to high, medium and low torque respectively, trends in bit torque and rate of penetration (ROP) in shale type formations can be used to separate the wear of milled tooth and PDC bits from changes in shale strength, it was not possible to interpret bit wear in non-shaly type formations, surface drilling measurements can be insensitive to major formation changes (eg. sand/shale boundaries), particularly in deviated wells.
Directional Drilling Azimuth Reference Systems
Authors: Wright J. W. 
Published: December 2007

Abstract
This paper will examine the primary azimuth reference systems currently used in directional drilling and their interrelationship when used in this application. This will include True North and Magnetic references with particular detail given to Grid Coordinate systems (ie. UTM, Lambert, Geographic, and Local). A simple field-proven method is also presented to help avoid confusion when converting from one system to another.
Accurate Surveying: An Operator's Point of View
Authors: de Lange J. I. , Twilhaar G. D. Nijen , Pelgrom J. J. 
Published: December 2007

Abstract
The achieved survey accuracy from the modern survey tools can be quantified by analysis of run data. Knowledge of the achieved accuracy, often better than the beforehand estimated accuracy, could result in reduced surveying cost and less rig time spent on surveying. Survey companies are urged to improve QA/QC and to provide the operator with ‘simple’ yardsticks with which to judge actual performance.
Technical Considerations in the Certification of Drilling Units for Worldwide Service
Authors: Thomas R. L. , Richardson K. L. , Abad E. 
Published: December 2007

Abstract
Technical considerations in the certification of Drilling Units for World Wide Service.
The design of the latest generation of offshore drilling units for operation world-wide has presented the greatest challenge to the offshore industry since drilling operations first moved offshore over thirty years ago. None have been more challenged than the electrical and instrumentation engineers tasked with the design of the power and control systems that enable these units to maintain station and conduct drilling operations under adverse environmental condition. An integral part of their job is to arrange the system and select components in conformance with the requirements of the flag state, various coastal states, certifying authorities and classification societies.
Such regulations vary not only in scope but also in the manner in which identical concerns are addressed. Designing for compliance with all the pertinent requirements presents a complex task for the engineer.
This paper will outline the major requirements pertinent to electrical and electronic systems of the regulations and rules of IMO, the United States, Canada, United Kingdom, Norway and one major classification society, highlight the major differences in their scope and approach and outline suggestions on how simultaneous compliance can be achieved.
The authors will draw on ABS’ experience in the classification and certification of several drilling units recently completed or presently under construction.
A Shallow Gas Research Program
Authors: Grinrod M. , Haaland O. , Ellingsen B. 
Published: December 2007

Abstract
Operational problems associated with the occurence of shallow gas in offshore drilling led Statoil to initiate a massive research program. The program consisted of the following subprojects: Revised drilling procedures, shallow gas drainage, multistage cementing, gas tight cement, diverter systems, rig ventilation systems and emergency anchor release.
Emphasis in this paper is placed on the experience from the West Vanguard blowout, and results from the subprojects on diverter systems, drilling procedures, quick anchor release and ventilation systems.
Other papers (reference 1, 2) give information on development of gas tight cement, stage cementing and additional background on shallow gas drainage.
Make-up of Fiberglass Tubulars
Authors: Stringfellow William D. 
Published: December 2007

ABSTRACT
The use of downhole Fiberglass Reinforced Plastic (FRP) tubulars to combat the effects of aggressive corrodents is increasing. Field experience indicates that the significant differences between the more conventional metallic tubulars and FRP tubulars are not clearly understood. This same experience has indicated a need for specialized tools for handling and make-up of FRP tubulars.
This paper presents a basic level overview of the material properties of FRP tubulars, including a comparison with K-55 steel tubulars, with emphasis on the impact these properties have on the make-up of the API 8 Round connection. Also presented is a description of a power tong developed specifically for the make-up of FRP tubulars. The discussion will include design parameters, used in the design of this tong, as well as laboratory and field test results.
Measurement of BHA Vibration Using MWD
Authors: Close D. A. , Owens S. C. , MacPherson J. D. 
Published: December 2007

Abstract
Excessive drill string vibration can lead to partial or catastrophic failure of bottom hole assembly (BHA) components. This paper presents data from a microprocessor based downhole vibration data acquisition and recording system, located within a host MWD (Measurement While Drilling) collar in the BHA.
Four case studies of vibration levels attained during commercial drilling operations are presented. These examples include vibration monitoring during reaming, drilling a casing shoe, and drilling new formation. Generally, lateral accelerations were an order of magnitude greater than longitudinal accelerations. In one example, catastrophic failure of MWD components resulted from sustained high-level lateral vibrations.
Data collected to-date has been used to optimize BHA components and define the down hole vibrational environment. Future information obtained by the monitoring system will be of value in verifying and calibrating computer models.