bluuebunny/crossref_metadata_2025_split huggingface dataset:
New Composite Fracturing Plug Improves Efficiency in Coalbed Methane Completions
Authors: Guoynes J.C. , Toothman R.L. , Berscheidt K. , Malimasura P.R. 
Published: December 2007

Abstract
Success in coalbed methane (CBM) development projects can be attributed to efficient hydraulic fracturing of multiple coal seams and quick online gas production. Because the coal can be naturally fractured, friable, and somewhat plastic in nature, successful stimulation can be challenging.1 Typical cased or openhole completion methods involve hydraulic fracturing of the coal seams. The seams may either be commingled and fractured together or isolated to perform staged fracturing treatments. Zonal isolation historically has been achieved when operators set inflatable plugs in the openhole or cast iron plugs in casing between stimulation intervals. Many operators use foamed fracturing fluids to enhance flowback and fracture closure after the initial treatment.
Inflatable packers have not been reliable in openhole completions, and this technology is developing at a slow pace in the industry. Difficulties also occur in either drilling or retrieving cast iron plugs used to isolate stimulation intervals in cased hole CBM completions. When multiple cast iron plugs are used in a single well, the difficulty in drilling out these plugs increases with the number of plugs. The increased difficulty is caused when the steel slips are drilled through and the remaining portion of the plugs drop on top of the undrilled plug or plugs left below. This remaining portion of the upper plug rotates freely on the fracturing sand and lower plug, increasing the drillout time on successive plugs. Retrievable plugs are difficult to remove because the fracturing sand left in the wellbore frequently enters the retrievable plug, creating releasing problems. Removal of cast iron plugs has taken as long as 8 days in some CBM completions.
A new composite epoxy-glass fracture plug was designed for use as an aid in the completion of multiple coal seams, allowing staged zonal treatment with flowback capabilities after treatment. The fracturing plug is made of an easily drillable, lightweight, composite material with no metal. The composite plug greatly reduces drilling time and drilling difficulties.
Case histories of more than 100 CBM wells that were completed with composite fracturing plugs are summarized in this paper. The new plug, combined with nitrogen-foam stimulation, improves completion efficiency and greatly reduces associated rig time in CBM operations. In addition, the new plug design greatly reduces the potential for downhole tool problems, including wellbore debris. Use of the new plug allows the operator to achieve wellstream production 30 days sooner than with previous plugs, allowing more rapid degasification of the coal.
P. 603
The Dual Laterolog-Rxo Tool
Authors: Suau J. , Grimaldi P. , Poupon A. , Souhaite P. 
Published: December 2007

Introduction
The Laterolog*, developed by H.G. Doll, has answered the need for a tool capable of producing useful resistivity measurements even when R /R is very high, as in the case of carbonates and evaporites drilled with salty mud. In invaded formations where R is greater than R it is better adapted for R determination than the induction log. The laterolog has also provided improved thin-bed resolution. Field laterologs have taken two different forms: Laterolog 7 using seven small electrodes, and Laterolog 3 with a central electrode and two long guard electrodes. As shown in Figs. 1a and 1b, in each tool a measure current i, from the central electrode is focused into the formations by bucking currents, i, of the same polarity. These are fed from symmetrical, short-circuited electrodes above and below the central electrode. The intensity of this focusing current (i a) is automatically and continuously adjusted so that under most conditions the measure current (i) flows outward from the sonde into a horizontal slice of formation of approximately constant thickness.
An Approach to Analyzing Multiple Causes Of Subsidence
Authors: Green Joseph P. 
Published: December 2007

Abstract
Negative changes in surface elevation (subsidence) have been recorded in many parts of the world and generally attributed to any one of several possible causes. Down-hole monitoring equipment is effectively being employed in some fields to relate subsurface compaction to surface subsidence, while in many other areas the necessary background history for such monitoring is not available.
This paper is a modified case history, wherein the relative amounts of three independent, simultaneously acting causes of subsidence were determined without the benefit of subsurface compaction surveys.
Through this analysis, subsidence control measures can be effectively implemented without the risk of over-reacting to one cause while possibly neglecting another.

Introduction
Previous attempts to adequately explain Previous attempts to adequately explain subsidence in a certain Southern California oil field (anonymity is required, as some of the basic data are restricted) were unsuccessful because single-cause theories had been employed.
This paper relates the effect of each of three independent causes of subsidence, acting simultaneously in the field. From this analysis, a workable method was developed for predicting either the rate of future predicting either the rate of future subsidence, or the means and location for providing corrective measures.

Causes
Subsidence throughout the world has been well documented, particularly where it is associated with fluid extraction. Shallow, freshwater production was responsible for some 25 feet of subsidence at Mexico City, and some areas in the San Joaquin and Santa Clara Valleys of California have decreased 28 and 13 feet, respectively. In Tokyo, Japan, some two million people now live below mean high tide (13). The list of areas where subsidence, associated with fresh-water withdrawal, has been less dramatic is nearly endless.
Oil-field operation associated with subsidence was documented nearly 60 years ago in the Goose Creek field, Texas.
Differences in Behavior of Fresh and Aged East Texas Woodbine Cores
Authors: Richardson J.G. , Perkins F.M. , Osoba J.S. 
Published: December 2007

Abstract
Laboratory experiments have shown profound differences in the behavior of so-called "fresh cores" from the East Texas field and of the same cores after extraction with organic solvents. The residual oil saturation remaining after water flooding "fresh cores" was appreciably lower than the corresponding saturations after flooding extracted cores. This behavior was also reflected in the water-oil relative permeability-saturation relations, which were more favorable for high oil recovery from the fresh cores.
These differences were evident not only in the amount of residual oil left after water flooding, but also in the saturation water remaining in the core after displacement by oil. Residual water saturation after displacement of water by oil was higher in the fresh cores than in the extracted cores. Capillary pressure-saturation relations were also different for the fresh and extracted cores.
Imbibition experiments indicated that both fresh and extracted East Texas cores are preferentially water wet, but the rate of imbibition of water was higher for samples after extraction than it was for fresh core material.

Introduction
Several years ago a series of water flooding tests was made in the laboratory on a number of Woodbine core samples from the East Texas field. These samples had been stored in containers open to the air and were extracted with organic solvents before they were subjected to the laboratory tests. After water flooding, the residual saturation of kerosene, which was the oil used in the tests, was found to average about 30 per cent.
Seismic Environment of the Southern California Coastline 1: Palos Verdes to Dana Point
Authors: Ploessel Michael R. 
Published: December 2007

Abstract
The southern California coastline lies within one of the more active seismic regions of the world. The Newport-Inglewood Fault System is within 12+ miles of the coastline, crosses the shoreline near Newport Beach, and from seal Beach to Dana Point is within 2+ miles of the shore. Point is within 2+ miles of the shore. In addition, the San Andreas, San Jacinto, San Gabriel, Sierra Madre, Whittier, Norwalk, Elsinore, and other active or potentially active fault zones are within 60+ miles of this coastal area.
Two major earthquakes have been recorded as heavily damaging the area. On December 8, 1812, a major earthquake wrecked the Mission San Juan Capistrano, (maximum Modified Mercalli Intensity IX) and on March 10, 1933, the Long Beach Earthquake, (Magnitude 6.3, Maximum Modified Mercalli Intensity IX) with an epicenter off Huntington Beach did considerable damage to Long Beach and Los Angeles.
The record of past seismic activity indicates that this area, which is daily becoming more densely populated and developed, will experience an earthquake of magnitude 6 or greater within the next 50 to 100 years. Such an earthquake may produce intense shaking lasting 30 to 60 seconds or longer with peak ground accelerations of 30 to 50 per cent gravity (Maximum Modified Mercalli Intensity VIII to IX). Such shaking could seriously damage many of the structures within the area, trigger new landslides, and reacivate existing landslides. The low lying alluvial area from San Pedro to Newport Beach will experience more intense shaking and damage than the cliffed bedrock areas of Palos Verdes, Corona del Mar, Laguna Beach, and Dana Point. The alluvial area, with the Point. The alluvial area, with the water table within a few feet of the surface will possibly experience liquefaction and ground lurching. All future construction within this area should be designed and built with due consideration of the areas seismic environment.
A Visual Study of Waterflooding a Microlayered Sandstone
Authors: Gring Larry M. , Caudle Ben H. 
Published: December 2007

Members AIME

Introduction
One task that the production engineer faces when evaluating the potential success of a waterflooding project is the forecasting of recovery at water breakthrough. The heterogeneous nature of sandstones makes this extremely difficult. However, experimental laboratory and field work have presented the engineer with some insight presented the engineer with some insight into how to approach the problem. To contribute to this insight, the author has investigated waterflooding a micro-layered sandstone.
It has been deter-mined that microlayers exist in man sandstones that appear to be homogeneous. Figure 1 is a photographic enlargement of typical photographic enlargement of typical microstrata investigated. To better understand the function of the microlayers in the waterflooding process, small linear laboratory flow cells have been constructed and subjected to the waterflooding process. The author sought to determine whether consideration of each stratum individually with to respect to its porosity and permeability was necessary, or whether permeability was necessary, or whether an average permeability and an average porosity would be acceptable. porosity would be acceptable.

GEOLOGY OF THE SANDSTONE
The sandstone used as the porous media in the flow cells was collected from an outcrop in southern Oklahoma near Calvin. The Calvin formation is a medium to silty grained, grey and brown, massive and thin bedded sandstone. The lower unit of the formation has tongues of sandstone and siltstone which break off of the bottom of this unit and intertongue with the shale of the underlying Senora formation. It is from this lower unit that the samples for this investigation were collected. Figure 2 is an example of the sandstone.

CONSTRUCTION OF THE FLOW CELL
The original sandstone samples taken from the Calvin site were in layers ranging from four to ten inches thick. The shale had weathered sufficiently to permit removal of large blocks of the sandstone. These large blocks were sliced into slabs approximately 5/8 inch thick. The slices were made perpendicularly to the bedding planes so that as many layers as possible were exposed. The dimensions of the cell were sketched on these slabs, with the longer dimension being parallel to the layering. A diamond cutting saw was used to cut the pattern from the slab of sandstone. The pattern from the slab of sandstone. The rectangularly shaped stone was then placed on a surfacing machine to cut away sufficient sand to make the top and bottom surfaces of the stone parallel to one another. The surfacing was required so that when the stone was machined to the desired thickness, it would be uniformly thick.
Natural Gas From Abroad
Authors: Hunsaker Barry 
Published: December 2007

To keep pace with our burgeoning natural gas requirements, most experts agree that even under the most favorable circumstances, this country is going to have to manufacture high Btu pipeline gas from coal and oil products, and import huge quantities of natural gas from abroad in the form of LNG (Liquefied Natural Gas). How much LNG? In the range of 1 to 2 trillion cubic feet per year by 1980 and in the range of 1.5 to 4.0 trillion cubic feet per year by 1985. Where will this LNG come from? The most likely of the present known sources are Algeria, Trinidad, Venezuela, Nigeria, Russia and Libya. Of these, Algeria contains very large reserves of natural gas, conservatively estimated at 100 to 150 trillion cubic feet. One field alone—the Hassi R'Mel Field—contains over 60 trillion cubic feet of recoverable reserves, making it one of the two largest gas fields ever discovered in the entire world. And the first project for the import of huge quantities of LNG for base load purposes project for the import of huge quantities of LNG for base load purposes will be the El Paso-Sonatrach project which I am going to describe. Sonatrach is the Algerian state-owned company charged with the responsibility of finding, developing and commercializing Algerian hydrocarbons. It is a large company staffed with relatively young, but technically competent, men who have assumed tremendous responsibilities and who are working about as hard as any group I know.
P. 1
Optimization of North Sea Turbo Diamond Bit Designs
Authors: Vennin Henri C. , Rowley David S. , Walker Bruce 
Published: December 2007

Discussion of this paper is invited. Three copies of any discussion should be sent to the Society of Petroleum Engineers office. Such discussion may be presented at the above meeting and, with the paper, may be considered for publication in one of the two SPE magazines.

Abstract
This paper explains how 9 5/8" turbine diamond bit designs for the North Sea were optimized through the combined results of practical field developments and analytical practical field developments and analytical design studies. Various mechanical characteristics such as bit face contour, diamond size, and diamond pattern were analyzed with the aid of the diamond drilling theory, taking into account the particular conditions encountered in North Sea drilling.
The mathematical model for rotary and turbine diamond drilling as used in this study was developed during recent years, and is now considered an effective aid to design optimization. The drilling theory is based on previously reported studies on the cutting actions of single diamonds in rocks, now expanded to encompass the total effect of all diamonds on the cutting surfaces of the bit. Using specific drilling conditions and rock properties, expressions for bit torque, properties, expressions for bit torque, penetration rate, rotary power and other penetration rate, rotary power and other performance characteristics are obtained in performance characteristics are obtained in terms of bit weight, rotary speed and the design parameters, like diamond size, fluid handling characteristics and geometric factors.
The evolution of the bit designs leads to a bit style which, within the known limitations on diamonds, has best theoretical performance and best field performance.

Introduction
In view of the expanding use and importance of turbo diamond drilling techniques, particularly in modern offshore development, particularly in modern offshore development, it is important to study the way in which diamond bits work under the specific conditions imposed by turbines, and to use this knowledge to improve the performance of the diamond tools. In this study, several practical turbo diamond bit design approaches are practical turbo diamond bit design approaches are studied analytically in an effort to isolate the best performing or "optimum" combination of bit design variables. The goal of optimization is to find the particular set of design variables which yields the highest penetration rate under the selected operating conditions, without violating any of the assumed practical limitations on loading and application of the diamonds, the diamond bits and the turbines.
Offshore Riser Slug Flow Avoidance: Mathematical Models for Design and Optimization
Authors: Yocum B.T. 
Published: December 2007

Yocum, B.T., Member AIME, Yocum International Asso.

Abstract
Losses in capacity of up to 50% in offshore oilfield production systems have been caused by poor design of two phase flow risers. Operators often do not realize the reduced capacity and additional costs caused by slug flow formation in risers, because the total system has been adjusted for slug flow avoidance, to a non optimum operating point. This paper (1) proposes a riser point. This paper (1) proposes a riser slug flow prediction chart with accept able slug and stratified flow range (2) develops a mathematical model for the elevation pressure drop and frictional pressure loss in the riser as a function pressure loss in the riser as a function of flow capacity (3) discusses the influence and characteristics of entering conditions (4) proposes several alternative designs to eliminate slug flow at minimum pressure loss and cost (5) recommends a inter company data gathering and testing program on risers, and, other vertical sections, in order to formulate more exact design models for optimization.

Introduction
During the 1960's progress was made in advancing the technology, and, rapid computer calculation, of two phase flow oilfield production systems. These utilize the flashing of the two phase mixture of oil and gas, to produce flow with pressure drop. Several large scale oilfield installations have been made both onshore and offshore. An example of a multiwell-flowline-trunkline system is shown in Figure 1. Such configurations of interdependent wells, branchlines, junctions, main trunklines, and gas/oil separators, often prove to be optimum cost solution in many fields; especially offshore fields. Large capital savings often are possible, both for initial and future facilities, as well as operating cost savings, when compared with the single well, single or looped flowline concept, producing to a centrally located gas/oil separator plant. Separate gas lines may be avoided by us of the trunk lines.
Cementing Research in Directional Gas Well Completions
Authors: Carter L. Greg , Cook Clyde , Snelson Lawrence 
Published: December 2007

This paper was prepared for the Second Annual European Meeting of the Society of Petroleum Engineers of AIME, to be held in London, England, April 2–3, 1973. Permission to copy is restricted to an abstract of not more than 300 words. Illustrations may not be copied. The abstract should contain conspicuous acknowledgment of where and by whom the paper is presented. Publication elsewhere after publication in the JOURNAL OF PETROLEUM TECHNOLOGY or the SOCIETY OF publication in the JOURNAL OF PETROLEUM TECHNOLOGY or the SOCIETY OF PETROLEUM ENGINEERS JOURNAL is usually granted upon request to the Editor PETROLEUM ENGINEERS JOURNAL is usually granted upon request to the Editor of the appropriate journal provided agreement to give proper credit is made.
Discussion of this paper is invited. Three copies of any discussion should be sent to the Society of Petroleum Engineers office. Such discussion may be presented at the above meeting and, with the paper, may be considered for publication in one of the two SPE magazines.

Abstract
This paper reviews some of the accepted causes of gas migration through a cemented column. Possible causes leading to gas migration in deviated borehole conditions have been considered in a laboratory model study. Emphasis has been primarily placed on cementing slurry properties and mechanical requirements necessary for a successful primary cementing job. Synthetic formation cores having various permeabilities were incorporated in the tests. permeabilities were incorporated in the tests. The permeable formation sand allowed early detection of gas diffusion into the wellbore as well as the migration of gas through the vertical cemented column.
Factors found to be most important for prevention of gas migration were: prevention of gas migration were:Mud-Cement Density (Effectivehydrostatic head)Cement Filtration ControlCement Viscosity or GelationBorehole Mud RemovalSetting Time or TemperaturePipe MovementCentralization

Introduction
Gas communication through a cemented annulus has been recognized as a major problem for a considerable number of years. With increased drilling activity taking place throughout the North Sea it has become increasingly difficult to combat because of the directional drilling of a number of wells from one location.
The completion of wells for the recovery of gas in a directional hole is similar in many respects to that used for the recovery of gas in a straight hole. The primary concern in any well is the isolation of zones and this is particularly difficult in the case of particularly difficult in the case of completing a well with a deviated borehole.
Previously gas migration in a wellbore was considered to exist only at the casing-cement or cement-formation interfaces, and bonding was considered to be a major cause for gas communication. This is still a major factor to contend with; however, it is not the only problem that may he responsible for gas communication between multiple permeable formations.