bluuebunny/crossref_metadata_2025_split huggingface dataset:
Numerical Simulation of Pressure Behavior In a Fractured Reservoir
Authors: Chiang C.P. , Kennedy W.A. 
Published: December 2007

Abstract
A simulation model of a reservoir with a symmetrical-horizontal fracture extending from the wellbore to the midpoint of the drainage radius was constructed.
The mathematical equation was developed for the case of single-phase unsteady state fluid flow. A solution for an infinite reservoir was obtained numerically and used for pressure drawdown and buildup analysis. The pressure drawdown and buildup analysis. The numerical results shows that:
1. On pressure drawdown and buildup curves, two straight lines are obtained; the first straight line with lower slope yields the effective permeability of the matrix and fracture, and the second straight line with greater slope yields the permeability of matrix.
2. The time of bend between the straight lines increases with increase in fracture radius. As the fracture radius approaches infinity, only one straight line of the Odeh type is obtained.
3. Extrapolation of the first straight line portion of the buildup curve may lead to an incorrect value of the static reservoir pressure.

Introduction
Analysis of pressure buildup and drawdown data is recognized as a powerful tool by the production and reservoir engineer seeking to production and reservoir engineer seeking to characterize the reservoir. Most pressure analysis techniques have assumed homogeneous reservoirs, i.e. the porosity and permeability are constant. However, some prolific wells produce from fractured reservoirs. These produce from fractured reservoirs. These reservoirs contain two distinct types of porosity and permeability, namely fracture porosity and permeability, namely fracture and matrix. Since the fractured region has higher permeability, reservoir-engineering analysis based on a homogeneous reservoir may lead to erroneous results. The purpose of this study is to develop a mathematical model which will simulate the pressure drawdown and buildup curves that would be obtained from a reservoir with a symmetrical-horizontal fracture around the wellbore. The mathematical model is developed by assuming a cylindrical reservoir of drainage area of uniform thickness is penetrated by a single production well at its center. The two -dimensional diffusivity equation for single phase flow was used to obtain pressure buildup phase flow was used to obtain pressure buildup and drawdown curves. It was necessary to obtain a constant rate solution to the equation because of the mathematical complexities introduced by the fractured reservoir geometry.
Economic Analysis of Drilling Fund Programs
Authors: Ambler Alan C. 
Published: December 2007

Abstract
The "Drilling Fund" method of financing oil and gas exploration and development has mushroomed in recent years and has become an important part of the independent's source of capital. This paper compares the various types of fund programs available, primarily from the investigators point of primarily from the investigators point of view. The investor's side is taken rather than the operator's because drilling fund participation interests have to compete with participation interests have to compete with other forms of investment in the capital marketplace, and fund was are not easy to sell to the prospective investor. Oil operators need to know and understand their investor partner's expectations, tax problems, and other reasons for getting into the oil business through the drilling fund medium.
Most fund programs are limited partnerships whereby the oil operator is the general partner and the limited partners are a group partner and the limited partners are a group of high-tax-bracket investors. Other programs are joint ventures between operator programs are joint ventures between operator and investors. The economic comparisons in this paper are based on typical or "average" industry statistics for finding and developing domestic onshore oil and gas reserves. The types of fund structures compared are (a) All costs paid by investors — operator has straight overriding royalty interest, (b) All costs paid. by investors — operator has back-in interest after payout, (c) Investors pay all intangible costs, operator pays all tangible costs, income is shared.
If the government does not interfere, drilling fund programs will have an increasingly important influence on exploration and development operations in the future.

Introduction
Over the next decade there is going to be an ever widening gap between the supply of hydrocarbons in the United States and the demand for these natural resources.
Laboratory Evaluation of Waterflood Behavior of Vugular Carbonates
Authors: deZabala E. F. , Kamath J. 
Published: December 2007

Abstract
Laboratory evaluation of waterflood behavior of vugular carbonates is subject to significant uncertainty. Even basic parameters such as residual oil saturation are difficult to estimate and depend on experimental conditions. We use X-ray Computed Tomography (CT) scanning to characterize the porosity, permeability, and waterflood displacement behavior in rocks from two carbonate settings. We find that the porosity and permeability distribution are dissimilar. This causes the dependence of their residual oil saturation on water flow rate to be very different. We attempt conventional methods to extract meaningful information from the data but find them inadequate.
What is Being Done About the Natural Gas Shortage
Authors: Sampson H.M. 
Published: December 2007

Abstract
A natural gas shortage has definitely been established. Experts agree that demand has, and will continue to out-strip supply.
The Federal Power Commission has overcompensated in trying to protect the ultimate consumer from the standpoint of price - - with the result that they have price - - with the result that they have failed to protect him on supply.
This myopia must now give way to some reasonable basis of reflecting fair market value, which will not be subject to future change. Industry must be encouraged to solve its own problem. Gas from Canada, Alaska, synthetic fuels, and liquid from foreign sources and nuclear stimulation offer a possible supplemental source of supply.
Fortunately, the Federal Power Commission and its staff now fully recognize this serious problem that confronts the industry and is now planning some possible solutions.
The industry and government must accept the financial and moral responsibility for a vigorous unrelenting search which must be conducted to find the gas necessary to maintain a viable industry, protect the consumers and the national interest.
The Engineer's Relationship to Oil Spill Laws and Regulations
Authors: Spurlock R.C. 
Published: December 2007

Introduction
Increased awareness of laws and regulations pertaining to oil spills will be required of engineers in the petroleum industry during the decade of the '70's. We have already seen a number of instances where operators have been cited and eventually fined for violation of one of the several statutes which cover accidental or deliberate release of oil or similar materials.
For the purpose of our discussion today, I will restrict my comments to applicable federal laws and regulations and will exclude any reference to state or local regulations. In order to understand where we are today, it seems appropriate to briefly review the historical development of antipollution or environmental legislation.
RIVERS AND HARBORS ACT OF 1899
As early as 1899 the Congress passed the Rivers and Harbors Act, sometimes called the Refuse Act, which included the following:
It shall not be lawful to throw, discharge, or deposit, or cause, sufferor procure to be thrown, discharged, or deposited either from or out of anyship, barge, or other floating craft of any kind, or from the shore, wharf, manufacturing establishment, or mill of any kind, any refuse matter of any kind or description whatever other than that flowing from streets and sewers and passing therefrom in a liquid state into any navigable water of the United States, or into any tributary of any navigable water from which the same shall float or be washed into such navigable water: … whereby navigation shall or may be impeded or obstructed.
Clearly, the intent of the legislators who drafted this bill over 70 years ago was to prohibit the dumping of floating refuse which prohibit the dumping of floating refuse which could be a danger to marine navigation.
Interpretation by the courts over the years, however, has enhanced the usefulness of the Rivers and Harbors Act of 1899 in controlling and abating pollution in our nation's rivers and streams. As recently as 1966, the U.S. Supreme Court stated: "The word 'refuse' includes all foreign substances and pollutants apart from those 'flowing from streets and sewers and passing therefrom in a liquid state' into the water course."
This broadening of the original language has permitted enforcement agencies to apply the 1899 law to current antipollution activities, especially in the area of oil spills.
Design of Pipelines for the Simultaneous Flow of Oil and Gas
Authors: Baker Ovid 
Published: December 2007

Abstract
Measurements were made of pressure drops for oil and gas flowing simultaneously through four to ten inch diameter pipelines. These results were related with data from the literature for one-half to three inch diameter pipelines. Previously published data were used to construct a generalized chart for predicting the type of flow pattern in the pipeline. The flow patterns described are bubble flow, plug flow, stratified flow, wavy flow, slug flow, annular flow, and spray flow. Our experimental data were shown to be consistent with the generalized flow pattern chart.
The calculation method proposed by Lockhart and Martinelli for designing two-phase pipelines was shown to be inadequate for larger diameter lines and also for some flow patterns. Modifications of the above method in the form of separate equations for each type of flow pattern are presented.

Introduction
In recent years there has been an increasing tendency to transport both oil and gas simultaneously through pipeline gathering systems. Trends toward central separator batteries, crude stabilizations, and total well stream processing in distillate type fields have emphasized the need for better information on the effects of liquid flowing along with the gas in pipelines.
The many fold increase in pressure drop when liquid is deliberately put into a gas pipeline is illustrated by Van Wingen's data in Figure 1. A look at the mechanism of two-phase flow will explain why pressure drops increase so much.
When two phases flow through the same pipe the gas usually flows faster than the liquid. The liquid accumulates in the pipe and reduces the cross sectional area available for gas flow. The pressure loss of a fluid flowing through a pipe is inversely proportional to the fifth power of the pipe diameter. The accumulated liquid in the line has the effect of reducing the diameter. A reduction of 20 per cent in diameter would cause a three fold increase in pressure drop, while a 60 per cent reduction would increase pressure drop one hundred times.
At some ratios of gas to liquid flowing, the surface of the liquid is very disturbed. There are many projections of liquid waves or ridges into the gas stream. For a half century studies have been made of the effect of roughness of inside pipe surface on pressure drops. Various friction factor charts taking roughness into account are available.
Predicting Gas Reserves in Abnormally Pressured Reservoirs
Authors: Hammerlindl D.J. 
Published: December 2007

Abstract
This paper is a study of abnormally high-pressured depletion-type gas reservoirs. In these reservoirs two distinct slopes are evident when a plot of shut-in bottom-hole pressures vs cumulative production (P/Z plot) pressures vs cumulative production (P/Z plot) is used to predict reserves. The final slope of the P/Z plot is steeper than the initial slope; consequently, reserve estimates based on the early life portion of the curve are erroneously high. The initial slope is due to gas expansion and significant pressure maintenance brought about by formation compaction, crystal expansion and water expansion. The early performance of the reservoir, as it appears on a P/Z plot, is due to the effective compressibility of the system. Effective compressibility varies from gas compressibility (theoretical P/Z performance) by the effects of the above mentioned pressure maintenance. At approximately normal pressure gradient the formation compaction is essentially complete and the reservoir assumes the characteristics of a normal gas expansion reservoir. At this point effective compressibility is about equal to gas compressibility, and this accounts for the second slope. Many costly decisions are based on the early life extrapolation of the P/Z plot. Therefore, it is necessary that we plot. Therefore, it is necessary that we understand the effects of hydrocarbon pore volume change on reserve estimates, productivity and abandonment pressure.
Two methods have been derived for correcting reserve estimates from the early life data using formation compressibility, gas production and shut-in bottom-hole pressures. The first method uses the ratio of the average effective compressibility to the average gas compressibility, while the second method includes compressibility in the expansion term of the material balance equation. The developed corrections are accurate in theory, but such required information as formation compressibility is based on limited empirical data. This must be kept in mind when using the family of curves provided in this paper. An effort has been made to help establish abandonment pressure and to reconcile other related compaction problems.

Introduction
This paper is a study of abnormally high-pressured depletion-type gas reservoirs. In these reservoirs two distinct slopes are evident when a plot of shut-in bottom-hole pressures vs cumulative production (P/Z plot) pressures vs cumulative production (P/Z plot) is used to predict reserves. The final slope of the P/Z plot is steeper than the initial slope; consequently, reserve estimates based on the early life portion of the curve are erroneously high. The initial slope is due to gas expansion and significant pressure maintenance brought about by formation compaction, crystal expansion and water expansion.
Effects of Drilling Fluids on Gas Well Productivity
Authors: Methven Norbert E. 
Published: December 2007

Abstract
This paper defines a method of increasing gas recovery and reserves by maximizing natural gas well deliverabilities. This method involves prevention of formation damage while drilling, prevention of formation damage while drilling, completing, and working over gas wells.
Included is the definition of the formation damage mechanisms attributable to drilling, completing, and working-over operations. Formation damage, the principle deterrent to maximum-productivity and recovery, involves the physicochemical relationships of fluid-systems with the formation. These relationships are herein defined and then specifically extended to include the effects on gas reservoirs. Of particular importance is a treatise on the effects on the relative permeability to gas from hydrocarbon invasion. permeability to gas from hydrocarbon invasion. This treatise includes a means to evaluate the vaporization-equilibrium constants of the invading complex hydrocarbons. These principles have then been used to develop an oil base fluid system that precludes formation damage and that has a filtrate that will be vaporized by produced gas to preclude any reduction in produced gas to preclude any reduction in relative permeability to gas.
Also presented are computed data, laboratory data, and field data from wells drilled and completed with various fluid systems. These data include core data, return permeability data, back-pressure tests, well productivity histories, and pressure buildup surveys. These data show substantially increased initial and ultimate income from gas wells when non-damaged completions are effected.

Introduction
The current and forecasted natural gas shortages increase the importance of maximizing the initial productivity and ultimate recovery from gas wells. A frequent impediment to maximum well productivity and hydrocarbon recovery is formation damage that may occur during the drilling or completion operations.
Case History: Comparison of Advanced MWD and Wireline Resistivity Tools in Thinly Laminated Reservoirs, Offshore, Trinidad
Authors: May Bruce , Dattoo Bobby , Roeth Richard , Oberkircher Jim 
Published: December 2007

Abstract:
A direct comparison of the two most advanced resistivity devices currently in use, the MWD based EWR Phase 4TM and the wireline run Array Induction Tool (AIT)TM, is made. Both tools were run in a well drilled off of the East Coast of Trinidad by Amoco Trinidad Oil Company. The tools are run in their respective environments to enhance reservoir identification and characterization in thin, highly laminated reservoirs. The objective interval in this area was thought to have this type of reservoir characteristic, Both use multiple depths of investigation combined with good vertical resolution to determine true resistivity (Rt) and to identify invasion profiles. A comparison of the results of the tools are related to previous efforts with other logging devices and actual production results. The two tools are compared through both thinly laminated and thick sand sequences.

Introduction:
Samaan B-8(ST)X well in Samaan Field, offshore Trinidad provides an opportunity to compare resistivity log response between the MWD EWR Phase 4 tool and a high resolution wireline resistivity tool such as the Array Induction Tool in a thinly laminated sandstone reservoir. Recognition of pay in thinly laminated low resistivity sand sequences similar to the Samaan Field 4B Sand reservoir is important in an active exploitation program in this field. The EWR Phase 4 and the AIT obtain resistivity information under differing borehole and invasion conditions. Both resistivity devices respond to the thinly laminated nature of the 4B Sand reservoir.

Tool Specifications
EWR Phase 4
The EWR Phase 4 (Figure 1.) is a multiple depth of investigation MWD resistivity device that uses four transmitter receiver spacings. From these spacings, different depths of investigations can be derived using phase, attenuation or a combined phase/attenuation based measurement. The spacings include X-shallow (EWXP, 6-12 inches radius of investigation); Shallow (EWSP, 12-18 inches); Medium (EWMP, 24-30 inches); and Deep (EWDP, 36-40 inches). The three shallower reading devices propagate at a frequency of 2 MHz, while the deep reading curve is at 1 MHz.

The Array Induction Tool
The AIT Tool (Figure 2.) is also a multiple depth of investigation resistivity device. It utilizes 8 mutually balanced induction arrays, whose main coil spacings range from a few inches to several feet. A single transmitter coil operates simultaneously on several frequencies between 105 Hz to 104 Hz range.
P. 747
A New Analytical Method to Evaluate, Predict, and Improve CO2 Flood Performance in Sandstone Reservoirs
Authors: Bou-Mikael Sami 
Published: December 2007

Abstract
The Port Neches CO2 flood (Fig 1), is a joint project between the Department of Energy (DOE) and Texaco E&P Inc. (TEPI) that has been operating for nearly 3 years. This project represents another learning step in developing the CO2 technology. This paper serves as a vehicle for transferring the technology acquired by TEPI to the industry.
Reservoir selection for miscible CO2 injection is critical to the economical success of any new project. Vast amount of potential reserves throughout the Gulf Coast are awaiting the right application of CO2 technology. Identifying these reserves, selecting the appropriate recovery method and accurately predicting the recoverable reserves and recovery rates are the essential ingredients of a successful project.
This paper include a brief discussion of the Port Neches project performance to date and presents a methodology to select, evaluate and predict project performance based on analogy with other projects performed throughout the Gulf Coast. This analytical approach utilizes type-curves developed from several CO2 floods and can be used independently or in conjunction with other available methods such as reservoir simulation.

Introduction
The vast majority of CO2 flood projects today are being conducted in carbonate reservoirs in the Permian Basin. Industry efforts in the Gulf Coast have been limited in scope and usually on a smaller scale. Gulf Coast sandstone reservoirs differ from those in the Permian Basin in terms of their matrix, reservoir architecture, oil composition, drive mechanism and recovery rates. Their suitability to CO2 flooding also varies.
The principal objective for CO2 projects in the Gulf Coast Region in the past has been to achieve miscibility early in the life of the project in order to maximize recovery. This objective has focused the oil industry for CO2 candidates selection on high pressure strong water-drive reservoirs in order to attain miscibility quickly. These water-drive reservoirs have very low residual oil saturation in the swept area, Which has often led to poor performance under CO2 flooding.
P. 177
Improved Oil Recovery for Independent Oil & Gas Producers
Authors: Sgro Anthony G. , Kendall Richard P. , Kindel Joseph M. , Webster Robert B. , Whitney Earl M. 
Published: December 2007

Abstract
There are more than fifty-two hundred independent oil and gas producers operating in the United States today (based on current IPAA membership figures). Many of these companies have instituted improved oil recovery programs in some form, but very few have had access to the state-of-the-art modeling technology routinely used by major producers to manage these projects. Since independent operators are playing an increasingly important role in production of hydrocarbons in the United States, it is important to promote state-of-the-art management practices, including the planning and monitoring of improved oil recovery projects, within this community. This is one of the goals of the Strategic Technologies Council, a special interest group of Independent Oil Gas producers.
This paper will describe a project which focuses on the distribution of advanced reservoir management technologies (geological, petrophysical, and engineering) to independent producers. The evolving information highway, specifically the World Wide Web (WWW), serves as the distribution medium. The procedure for launching petrotechnical applications and retrieving results over the WWW will be presented. A paradigm for the interaction between the independents, the petroleum service sector, and government will also be presented. Of principal concern is the cost of making high-tech modeling applications accessible to independent operators.
DOE's Class 1 Projects: Delivering Results
Authors: Cole E. Lance , Grabhorn Merle D. 
Published: December 2007

Abstract
Industry cost-shared field demonstration projects being conducted in fluvial-dominated deltaic (Class 1) reservoirs as part of the Department of Energy’s (DOE’s) Reservoir Class Program are demonstrating cost-effective, practical technologies. Reserve development costs are less than or competitive with exploration or acquisition costs. Prudent technology applications are starting new waterfloods, giving new life to mature water-floods, creating successes in reservoirs where waterflooding previously failed, and starting successful waterfloods in reservoirs previously thought to be unsuitable for waterflooding. Successful field demonstration and technology transfer efforts are spawning additional technology applications outside DOEs Reservoir Class projects.