bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Comparative Analysis of the Production Characteristics of Cavity Completions and Hydraulic Fractures in Coalbed Methane Reservoirs
Authors: Goktas B. , Ertekin T. 
Published: December 2007

Abstract
Coalbed methane wells usually require a stimulation technique because their initial flow rates are often quite low. Hydraulic fracturing is the most common type of stimulation technique applied to coalgas reservoirs. Recently, open-hole cavity completions have become an alternative stimulation technique in coalbed methane reservoirs.
In this study, a three-dimensional, two-phase fluid flow model is used to compare production performances of the cavity-completed and hydraulically fractured wells in coalbed methane reservoirs. A static local grid refinement (LGR) technique is embedded into the model to adequately capture the flow behavior around cavity completions and hydraulic fractures without using excessively large number of grid cells.
The model utilizes a residual equation rather than a wellbore equation to determine the flow rates into the cavity and hydraulic fracture. Both cavity completions and hydraulic fractures are approximated as a combination of fine rectangular grid blocks. The constructed fine grid lines are terminated at the coarse and fine grid block interfaces by implementing the LGR technique developed. The generated flow equations for fine and coarse blocks are, then, solved simultaneously.
Flow performances of cavity completions and hydraulic fractures are compared for various coal seam permeabilities. It is demonstrated that permeability damage during fracturing may have significant impact on the flow performance of the hydraulic fracture. Hydraulic fractures without permeability damage associated perform better than cavity completions if permeability contrast in the coal seam is not significant. In strongly anisotropic systems, however, even if there is no formation damage due to fracturing fluid, cavity completions outperform hydraulic fractures.
A Modified p/Z Method for Coal Wells
Authors: Seidle John P. 
Published: December 2007

Abstract
A straight line, easy to use form of the mass balance equation, the "p/Z plot", is frequently used to determine both Original-Gas-In-Place and initial reservoir pressure of conventional gas wells and reservoirs. A coal well p/Z plot bends to the right, similar to that of a conventional gas well subject to water influx. The theoretical foundations to linearize this plot for coal wells were laid in a simulation study by King (ref. 1) with the introduction of his Z* variable and the resulting "p/Z* plot". However, when King's method was applied to actual coal wells, wildly erroneous results were obtained. Investigation of this failure resulted in a modified, more robust method. As did the original method, the modified method presented here allows determination of OGIP, initial reservoir pressure, and drainage area. This paper documents mathematical development of the modified method, application of both the original and modified methods to simulated coal well production data, and, lastly, application of the modified method to the actual production data which initiated this study.
Rock-Mechanical Model of Thin-Bedded Sands and Shales for Improved Fracture Height Prediction, Mesaverde Sandstone, Wyoming
Authors: Pantoja David , Hurley Neil F. , Graves Ramona M. , Mark Pearson C. 
Published: December 2007

Abstract
The purpose of this study is to construct a core- and log-based rock-mechanical model of thin-bedded sands and shales. The study area is North LaBarge field, Wyoming, where rocks of the Cretaceous Mesaverde Formation produce hydrocarbons from low-permeability, thin-bedded (0.5-10 in; 1-25 cm) sands and shales. Hydraulic fracturing is necessary to obtain production from this reservoir.
For roughly 90 ft (27 m) of core, permeabilities and p- and s-wave velocities were measured every 0.5 in (1.2 cm) using probe-type devices. Laboratory results were converted to subsurface conditions using pressurized core plugs, a full-waveform sonic log, and a density log. The resulting rock-mechanical model provides a detailed stress profile which can be used as input into computer models which predict fracture height. Such models generally use bulk-rock properties in which fracture heights are overestimated because the models do not take into account the ability of thin shales to impede fracture propagation.
Development of a Coiled Tubing Diametral Growth Model
Authors: Yang Y. S. , Gao C. 
Published: December 2007

Abstract
Coiled Tubing (CT) is subjected to plastic mechanical deformation as it is cycled on and off the reel and over the gooseneck. Repeated bending causes CT fatigue, and eventually failure. In the presence of an internal pressure, especially higher pressures (greater than 3,000 psi), CT fatigue is accompanied by diametral growth ("ballooning"). CT diametral growth can cause incompatibilities with deployment equipment and continuous use could thus cause severe mechanical damage to the CT. Therefore, an accurate predictive model for CT diametral growth is needed for both safety and reliability in CT operations.
A reliable CT diametral growth model has been developed based on test data and three-dimensional curve fitting. The developed model not only predicts CT diametral growth under various pressure and bending geometry conditions, but also evaluates the effects on CT growth of relatively small changes in tubing OD, wall thickness, material grade, internal pressure, and bending radius. These analyses will help operators detect early CT diametral growth before severe damage occurs, and eliminate or reduce operational factors that contribute to growth.
Shaly Sand Analysis using Density-Neutron Porosities from a Cased-hole Pulsed Neutron System
Authors: Odom Richard C. , Pavlakos Paul , Diocee Satwant S. , Bailey Shawn M. , Zander Dennis M. , Gillespie John J. 
Published: December 2007

Abstract
A density-based porosity derived from the attenuation of gamma rays created by inelastic scattering of fast neutrons has been developed1,2,3 for the Computalog PND-S pulsed neutron system. The utility of this cased-hole, density-based porosity is demonstrated in reservoir analysis of sand-shale sequences in western Canada, Texas gulf coast, and Montana. Applications (in combination with the cased-hole neutron porosity) include providing porosities where hole conditions make open-hole logging unviable, and in old wells where no modern porosity logs exist or the data is of questionable quality. Low porosity can be differentiated from gas-filled porosity with the use of this measurement in cased-hole prospecting.
In shaly sand analyses, the addition of this novel density measurement to the neutron porosity and SIGMA facilitates a more comprehensive description of the reservoir. LRHO, the pulsed neutron density parameter, and RATIO, the near-to-far thermal ratio, are shown as overlays to identify gas zones. The pulsed neutron density porosity IPHI, which is used in the log analysis examples, is generated by specifically characterizing LRHO for a well or field. A prototypical borehole compensated (BHC) algorithm, that generates neutron (AIPN) and density (AIPD) porosities characterized for specific casing sizes and lithologies, is also used in the log analysis examples. The measurement theory of the PN density is reviewed as it pertains to understanding the log examples.
The correlation with open-hole porosities is demonstrated in several of the log examples. Through application to some typical reservoir description and optimization problems, the log examples show the utility of these measurements in cased-hole reservoir analysis.
Unsteady-State Pressure Distribution Created by a Well with an Inclined Fracture
Authors: Cinco-Ley Heber , Ramey Henry J. , Miller Frank G. 
Published: December 2007

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

Abstract
An analytical solution was derived for the unsteady flow of a slightly compressible fluid toward a fractured well with an inclined fracture in an infinite slab reservoir. This solution was evaluated to obtain the dimensionless pressure drop at the fracture. Fully and partially penetrating fractures were considered. partially penetrating fractures were considered. Tables and graphs of dimensionless fracture pressure vs dimensionless time are presented. pressure vs dimensionless time are presented

Introduction
Hydraulic fracturing has been an effective technique to stimulate damaged wells or wells producing from a low-permeability formation. producing from a low-permeability formation. It has been established that the orientation of a hydraulic fracture is perpendicular to the direction of the least principal stress in the formation. The direction of the least principal stress is not always parallel or perpendicular to the plane of the formation. For this reason it is possible that some hydraulically fractured wells have inclined fractures.
Many authors have studied flow behavior in a reservoir produced through vertically and horizontally fractured wells.
At early times in the unsteady-state behavior of a fractured well there exists a linear flow perpendicular to the plane of the fracture. This can be recognized by a one-half slope line on a log-log graph of fracture pressure drop vs time. Following this flow pressure drop vs time. Following this flow period, there is a transition flow period that period, there is a transition flow period that depends on the geometry of the fracture-reservoir system. At long times, there is a pseudo-radial flow period, if the reservoir is pseudo-radial flow period, if the reservoir is considered of finite thickness and infinite radial extent, and the fracture is of finite extent.
No reference to transient pressure behavior for a reservoir producing through a well with an inclined fracture was found in the literature.
The purpose of this work is to present a solution of the unsteady-state pressure distribution created by a well with an inclined fracture produced at a constant rate.
Urban Oil Production and Subsidence Control - A Case History, Beverly Hills (East) Oilfield, California
Authors: Erickson R.C. , Spaulding A.O. 
Published: December 2007

Abstract
In only a limited number of hydrocarbon producing areas of the United States and producing areas of the United States and elsewhere has the production of oil and related fluids from subsurface reservoirs been correlated with surface subsidence and damage to property in the subsiding area as well as damage to wells and producing facilities as a result of compaction within the productive reservoirs. These limited phenomena have been observed and documented most notably in the Wilmington Oil Field in the southerly portion in the City of Los Angeles and portion in the City of Los Angeles and adjoining City of Long Beach.
The City of Los Angeles has permitted urban oil producing operations for the past 20 years in the belief that the risk of past 20 years in the belief that the risk of significant oil field subsidence is negligible and in the knowledge that should slight negative changes in the surface elevations be noted at or near the outset of production, measures can be taken to abate the condition before damage to surface improvements could occur.
The Beverly Hills (East) Oilfield was discovered during December 1964, and it soon became apparent that a major hydrocarbon reserve had been found. Within three years production rates exceeded 30,000 BOPD from production rates exceeded 30,000 BOPD from reservoirs as shallow as 3,600 feet beneath one of the most densely populated portions of the city. Clearly, the situation required assessment of the subsidence prospects.
The Beverly Hills (East) field is located within an east-west trending elongate complexly folded and faulted anticline situated on the northwesterly rim of the Los Angeles Basin at the common boundary between the cities of Beverly Hills and Los Angeles. Productive limits encompass approximately Productive limits encompass approximately 848 acres within which 6,200 individuals are currently receiving royalty payments. Development drilling has been conducted by two operators Standard Oil Company of California and Occidental Petroleum Corporation and by May 1, 1975, 118 wells had been completed of which 26 are water injection wells. As of May 1975, over 61 million barrels of oil and 124 million MCF of gas have been produced. Production during April 1975 averaged Production during April 1975 averaged 11,000 BOPD and 15,000 MCF of gas per day.
Marine Sewage Regulations and Disposal Methods
Authors: Chance Maurice J. 
Published: December 2007

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

Abstract
This paper provides an examination of the problems associated with the management of problems associated with the management of sewage discharges from watercraft and offshore platforms. Areas of emphasis include waste platforms. Areas of emphasis include waste treatment techniques, Federal legislation concerning waste discharges, and the contribution of discharges to the pollution of navigable waters of the United States.
The intent of the paper is to provide shippers, shipowners, and platform operators with the most recent information on marine sewage treatment systems.

Introduction
Environmental pollution has become a major concern. An increasing number of laws, regulations and standards are being proposed and promulgated to curb detrimental discharges into promulgated to curb detrimental discharges into U.S. waters. Although there are variations in the degree of control by the laws of the Federal Government, it is assured that the enforcement will require ships and offshore platforms to have total anti-pollution programs.
The need for regulatory compliance has initiated research programs for developing new ways and equipment to meet proposed standards. The regulations have also prompted investigations for monitoring instrumentation and methods for evaluating such systems.
This discussion includes three topics. The first is a description of the effects of sewage discharges. The second topic is a review of applicable regulations. The final topic is a description of sewage treatment systems which are available to the marine industry.

THE POLLUTION ASPECTS OF SEWAGE WASTE DISCHARGES
Sewage in its crude state contains many bacteria some of which are pathogenic. The bacteria vary more in kind than in quantity. Organisms found in soil, water, animal and human intestinal tracts may be found in sewage at different times. The bacteria are divided into two groups, aerobes and anaerobes. The former group is capable of transmitting typhoid, gastro-enteritis, para-typhoid, dysentery and cholera.
When sewage enters a waterway, a series of biochemical changes take place. Bacteria, algae, molds, and protozoa in the waterway decompose the sewage to nitrites, nitrates, sulfites, sulfates, and carbon dioxide. By photosynthesis, green plants in the waterway utilize the end products of decomposition for energy and release products of decomposition for energy and release oxygen to the water. The end result is self-purification of the water. This process progresses slowly and occurs only when a healthy progresses slowly and occurs only when a healthy balance between animal and plant life exists.
Fracturing Design Using Perfect Support Fluids for Selected Fracture Proppant Concentrations in Vertical Fractures
Authors: Harrington Larry , Hannah Robert R. 
Published: December 2007

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

Abstract
This paper presents a method of scheduling proppants in perfect or near perfect transport proppants in perfect or near perfect transport fluids to meet predetermined proppant concentrations in the fracture.
Early attempts at predicting proppant concentrations in fractures failed because of the very poor prop transporting ability of the available fracturing fluids. The formation of a sand bank in the bottom of a vertical fracture completely ruled out prediction of prop concentration based on theoretical leak-off parameters. For this reason such promising parameters. For this reason such promising techniques as partial monolayer propping and high strength proppant tail-ins were abandoned.
The development of cross-linked gel systems and ultraviscous fluids has revived interest in analytical scheduling since proppant transport in these fluids is virtually perfect.
A mathematical model of the fracture is considered with all the factors necessary to predict proppant concentration included. predict proppant concentration included. This development, in contrast to either gross averaging or finite difference solutions, has led to a closed form mathematical solution.
The technique presented allows selection of final fracture proppant concentration based on the fracture conductivity needed to meet design requirements. This concentration requirement and a fracture penetration requirement are used as computer inputs. The final computer printout presents the fluid volume required, the printout presents the fluid volume required, the required proppant amount, the pad volume needed, and a proppant addition schedule. Thus, all factors affecting reservoir improvement are considered by one computer program.

Introduction
When hydraulic fracturing first began, selection of treatment volumes, sand concentration and sand scheduling was strictly an empirical art. Treatment designs relied heavily on experience and subjective judgments of what was possible. The relationships between injection possible. The relationships between injection rate, leak-off coefficients, fracture width, sand concentration, and volume pumped were not completely understood.
After this initial period, several investigators began to develop and apply various analytical tools that helped to rationalize and quantify the techniques used. Significant developments occurred in the prediction of fracture area, fracture width, and productivity improvements. productivity improvements.
Prepack Technique Using Fine Sand Improves Results Of Fracturing And Fracture Acidizing Treatments
Authors: Miller B. D. , Warembourg P.A. 
Published: December 2007

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

Abstract
Use of 100-mesh sand in a prepack stage ahead of the main stages of several types of stimulation treatments has greatly improved results of the treatments. The use of 100-mesh has proved highly effective in improving results of both conventional fracturing and acid fracturing treatments. The technique has been applied successfully in many types of formations in many areas.
Several theories have been advanced concerning the mechanism by which 100-mesh sand improves stimulation efficiency. Probably more than one of the mechanisms contribute. This paper describes the mechanisms by which 100-mesh paper describes the mechanisms by which 100-mesh sand may contribute to better results in various types of formations. Field results of use of 100-mesh sand in different areas and different formations are compared to results of more conventional treatments. Factors that may be involved in the design of the 100-mesh prepack stage are discussed.

Introduction
Originally, 100-mesh sand was used in an attempt to limit penetration of a fracture outward into the reservoir after a desired distance had been reached. The basic idea was to screenout or plug off the fracture at the tip with a pack of the fine sand. Additional fluid injected pack of the fine sand. Additional fluid injected would then tend to widen the fracture and increase conductivity. Whether or not complete plugging actually occurred at the tip of the plugging actually occurred at the tip of the fracture is a matter of conjecture. However, some of the early jobs indicated that some action of the fine sand was contributing to the successful fracturing of reservoirs that had previously screened out. In fact, wells that could not be successfully fractured with small sand (40/60 mesh) would accept large volumes of 10/20 sand at concentrations above 2 – 3 pounds per gallon if a pad of fluid containing 100-mesh sand was used ahead of the main frac stage. Several successful treatments using this technique were completed in the Rocky Mountain area, and it was noted that production results were better even in those areas where conventional fracturing had been successful. Use of the prepack technique with 100-mesh sand grew rapidly, and it is now becoming almost a standard procedure in many areas. It has also proved highly successful in acid fracturing treatments.
Drilling Cooperatives: One Strategy for Reducing Drilling Cost and Risk
Authors: Harris B. W. 
Published: December 2007

Abstract
During a period of rig scarcity, three small, independent operators joined together to present an offshore drilling schedule of sufficient duration to interest a drilling contractor and greatly reduce mobilization costs. Each operator had found that for the market conditions at the time, remote, one-or two-well offshore drilling programs were prohibitively expensive. Also, the short duration of the operators' programs rendered them unattractive to the one drilling contractor capable of doing the work and in the best geographic position to significantly affect program costs. Combining the three drilling programs satisfied the contractor's desire to secure a long-term work contract and promised significant savings in expenditures for the operators. Each operator's drilling program was examined and priorities compared to determine and produce as many common elements in permitting, well design and evaluation needs as possible. The intent was to not only streamline and thereby accelerate certain processes but to maximize purchasing power with suppliers and service companies as well. Reductions in expenditures were anticipated to be 20 percent to 50 percent of total well cost, depending upon the operator. Risk reductions during periods of commonality in the combined program, such as mobilization and demobilization, were expected to be 50 percent and greater. Difficulties arose from conflicts between the common good of the group and each operator's natural self-interest. Because logistical and regulatory pressures caused the combined program to commence before all necessary contractual agreements were consummated, these conflicts were exacerbated.