bluuebunny/crossref_metadata_2025_split huggingface dataset:
Successful Matrix Acidizing of Sandstones Requires a Reliable Estimate of Wellbore Damage
Authors: Burkill G.C.C. , Lichaa Pierre M. 
Published: December 2007

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

Abstract
Successful matrix acidizing of sandstones for the removal of wellbore damage is dependent on a reliable estimate of wellbore "skin" and its radial extent. The value of these parameters is estimated from pressure-buildup parameters is estimated from pressure-buildup analysis. However, in depleted, multilayered reservoirs, the values obtained may vary considerably depending on the chosen method of pressure-buildup interpretation. pressure-buildup interpretation. For this study, pressure buildups before and after acidization were analyzed by both the semisteady-state solution of Horner and early time analysis of McKinley. These results were compared with the actual field results.
It may be concluded that the early time analysis of McKinley gave more probable results, but it should be stressed that, under these reservoir conditions, there is no absolute answer, and results from independent methods should be compared.

Introduction
At present, Cia. Shell de Venezuela is involved in an active stimulation program to optimize oil potentials from their Lake Maracaibo sandstone reservoirs. The choice of candidates and treatment design depends on a series of factors, but perhaps the most important is the extent of wellbore damage.
In the Horner method currently used, the skin factor and reservoir permeability are both determined by the slope of the linear portion of the buildup curve. If the linear portion of the buildup curve is chosen incorrectly, the calculation will yield either an excessive skin together with an overestimate of reservoir permeability or an underestimate of wellbore permeability or an underestimate of wellbore damage and a reduced reservoir permeability.
The present trend to "minifracs" (small frac treatments with sand using gelled gas oil as carrying fluid) for removal of wellbore damage does not depend too heavily on correctly interpreting the damage factor as the oil gains result from two mechanisms:skin removal if it exists, andincreasing the natural permeability in the nearby area of the well or permeability in the nearby area of the well or even fracturing into sands of improved permeability. permeability.
Constant Pressure Injection Test in a Fractured Reservoir-History Match Using Numerical Simulation and Type Curve Analysis
Authors: Locke C.D. , Sawyer W.K. 
Published: December 2007

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

Abstract
Water was injected at constant pressure into a single well in a pressure into a single well in a fractured reservoir for a period of 32 days followed by a 9 day shut-in period. Intake volumes of the injection well and pressure responses in 19 surrounding pressure responses in 19 surrounding wells were recorded during the entire test.
Type curves were generated by numerical and semi-analytical techniques to facilitate reservoir characterization from the constant-pressure, declining-rate injection data. A single-phase, three-dimensional, semi-compressible simulator was developed and used to match the field-results.
The fracture orientation trend of the reservoir was determined, and reservoir permeability and effective fracture length were calculated for the injection well. Type-curves are presented for use in evaluating the presented for use in evaluating the constant terminal pressure case for fractured wells.

Introduction
Hydraulic fracturing is used extensively to improve the economics of primary oil production and is being used increasingly in waterflood projects involving wells with severe skin damage, lower permeability reservoirs, and reservoirs with wells that were fractured for improved primary production. Previous fears that induced production. Previous fears that induced fractures may result in floodwater "channeling" to production wells are gradually dissipating as more is learned about the nature of these fractures. There is strong evidence to suggest that the vast majority of induced fractures are vertical and extend laterally in a preferred direction. Proper alignment of fractured wells for Proper alignment of fractured wells for pattern flooding can result in pattern flooding can result in displacement efficiency equal to or better than that of patterns using unfractured wells. Donohue, Hansford, and Burton investigated the effect of fracture orientation on displacement efficiency in pattern floods showing the importance of pattern alignment with respect to fracture direction.
A Practical Application of a Subsea Oil Production System
Authors: Chatas A.T. , Kin W.D. , Bendiks Carlos 
Published: December 2007

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

Abstract
A typical field application is defined, where the objective is to utilize a subsea production system to develop an offshore oilfield in an average water depth of 800 feet. Eight dually completed wells are required to achieve a production plateau of 25,000 BOPD. The SEAL production plateau of 25,000 BOPD. The SEAL Multiple-Well Manifold/Production Station was chosen for this application.

Introduction
Anticipation of offshore petroleum discoveries in profoundly deep water engendered the research and development of various subsea production systems over the past decade. Some production systems over the past decade. Some of them are now considered operational and available for practical application. One such system, pioneered by Mobil and completed by SEAL, is the Multiple-Well Manifold/ Production Station, which will be incorporated here Production Station, which will be incorporated here in the development of an example offshore oilfield.
This multiple-well station is intended for use where deviated drilling is possible from subsea locations, where wells may be drilled peripherally through a base template. The peripherally through a base template. The wells are then connected to a subsea work enclosure by use of wellhead connector assemblies. Functioning basically as a manifolding station, the subsea work enclosure provides a dry environment on the sea floor at atmospheric pressure, in which normal oilfield equipment may operate.
The example field under consideration lies offshore in 800 feet of water, about a mile from an existing platform. It contains two reservoirs that will be produced through dually completed wells to achieve a field production rate of 25,000 BOPD. The wells production rate of 25,000 BOPD. The wells are to be drilled by a floater rig, deviated through the drilling template that will serve as the base of the multiple-well station. Production will be manifolded on the seabed Production will be manifolded on the seabed through the subsea work enclosure and piped to the nearby platform for processing and transport to shore.
Problem Well Analysis - Pumping Oil Wells
Authors: Kelm C.H. 
Published: December 2007

Kelm, C.H., Member SPE-AIME, Amoco Production Co. Production Co.

Abstract
This paper presents practical methods of recognizing and analyzing problem well symptoms. It also discusses the required data and its use, as well as presents a "well checklist" that assists the engineer in analyzing well performance. The objectives of well analysis are to maximize producing rates and recovery within allowable, economic and/or reservoir restraints. Based on experience gained from beam pumped oil wells in West Texas waterflood projects, well analysis as presented can be applied to oil wells produced by other means of lift and reservoir drive mechanisms.

Introduction
Maximizing pumping oil well rates and reserves within certain restraints have always been the objectives of the petroleum engineers. One of the obstacles that prevents achieving these objectives is problems that occur within the wells. These problems can be associated specifically with the reservoir, the wellbore and near wellbore area and mechanical aspects of the producing well. In this paper the primary concern is with the problems of the wellbore or near wellbore area and/or the mechanical condition of the well.
Symptom recognition and definition of the cause of a problem can best be accomplished through regular collection and analysis of individual well production data. Although many times production data must be supplemented with other data to completely review performance.
In shallow West Texas waterfloods, where beam units are the prevalent lift mechanism, it has been found that constant review of overall project and individual well performance by the production engineer results in wells being maintained in their optimum producing condition. These reviews are facilitated by the collection and proper display of at least monthly well test and fluid level data or pump off control device pump time on every producing oil well. pump time on every producing oil well. A "well checklist" as developed in this paper, helps the production engineer organize well performance and mechanical data necessary for well reviews. Once the data is organized, performance analysis becomes a matter of interpreting the data and comparing the well's performance or predicted performance to that of another. predicted performance to that of another.
Peraguage - A Permanent Surface Recording Downhole Pressure Monitor - Through a Tube
Authors: Weeks Steve G. , Farris Gerald F. 
Published: December 2007

Abstract
A permanent means of continuously monitoring downhole pressures without interruption of producing or injection operations, was first tested in Germany more than 25 years ago. This initial development plus subsequent modifications each require an electric cable to transmit a signal reflecting downhole pressures. A new tool has been introduced which does not utilize any downhole electronics or electrical conduit. This pressure transmission system, or Permagauge, consists of a 3/32 inch O.D. tube, attached to the outside of the production tubing, connecting a surface recorder to a downhole chamber in communication with the well fluids. Downhole pressures are determined by adding the recorded surface pressures to the calculated pressure exerted by the weight of an inert gas column in the small tube. A portable surface unit provides versus time as portable surface unit provides versus time as well as a digital display for continuous pressure monitoring. pressure monitoring. Since initial installation, more than 75 Permagauges have been run, including installations in a CO2 pilot project in Southeastern Mississippi. Discussed are a general description of previously available remote reading bottom-hole pressure gauges, a resume of all Permagauge installations, plus detailed experience with the Mississippi plus detailed experience with the Mississippi runs verifying the accuracy of the Permagauge to be equal to wireline pressure surveys.

Introduction
Bottom-hole pressure data are routine requirements for evaluation of production and reservoir pressure response may be especially helpful in evaluation and control of supplemental recovery projects. This might include producing, build-up and static surveys as determined by pressure recorders run on wireline. However, frequency and number of wells surveyed may be limited due to interruption of normal production routine, as well as expense. Presence of some artificial lift equipment will prevent running conventional pressure surveys. Furthermore, production pressure surveys. Furthermore, production of highly corrosive fluids, together with potential damage from wireline cutting where potential damage from wireline cutting where plastic-coated tubing is installed, can also plastic-coated tubing is installed, can also be a deterrent to obtaining useful pressure data.
Permanent installation of a downhole pressure detector provides a means of pressure detector provides a means of continuously recording pressures and may aid in adjustment of fluid movement within a reservoir.
Evaluating Formation Damage in Low Permeability Sandstone
Authors: Pence S.A. 
Published: December 2007

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

Abstract
The massive gas formations in the Rockies, such as Mesaverde, will be among the sources of our future gas supplies. Effective stimulation treatments will be in larger volumes than the industry previously found economically feasible. Although higher gas prices make stimulating tight sands possible, the problem of selecting less damaging fracturing fluids remains. The effects of confining pressure, reported in the literature, have been confirmed in tight sandstone cores. These effects may make present test procedures for formation damage meaningless unless rigid test procedures are imposed in the laboratory. This paper describes equipment and techniques developed to evaluate damage caused in gas formation cores by candidate fracturing fluids.

Introduction
The massive gas formations in the Rocky Mountains such as the Pictured Cliffs, Mesaverde and Frontier will be among the sources of future United States gas supplies. Randolph has estimated recently that of 1,015 trillion cu ft of potential natural gas reserves, 600 tcf is presently noncommercial in the Green River, Piceance and Uinta basins. About half of this may someday be recovered by nuclear or by massive hydraulic fracturing.
The laboratory permeabilities, reported in the literature for cores from some of the above basins, did not agree with permeabilities derived from production tests in the field. Thomas and Ward have reported that in-situ permeability in very tight reservoirs is a permeability in very tight reservoirs is a strong function of water saturation and overburden or confining pressure. Unconfined Gasbuggy rock, for instance, had 10 to 20 times the permeability of its in-situ permeability. Similar effects have been reported earlier by Fatt and others.
Certainly these findings could have a pronounced effect on the accuracy and pronounced effect on the accuracy and reliability of laboratory measurements of permeability and perhaps, fluid-loss parameters used permeability and perhaps, fluid-loss parameters used when designing fracturing treatments. Since present methods of estimating formation-damage present methods of estimating formation-damage use permeabilities as their basis, a valid test procedure must take these findings into account. procedure must take these findings into account.

Formation-Damage Variables
An excellent presentation by Carney and Wieland discussed the evaluation of fracturing fluids for low-permeability gas formations. They classified formation damage due to migratory fines from the rock itself and due to liquid retention in the pores of the rock. Selection of the fracturing fluid to use in any particular formation is often done on the basis particular formation is often done on the basis of laboratory formation-damage tests.
Pressure-Transient Analysis of Perforated Slant and Horizontal Wells
Authors: Ozkan Erdal , Yildiz Turhan , Raghavan Rajagopal 
Published: December 2007

Abstract
This study investigates the transient pressure behavior of perforated slant and horizontal wells and discusses the implications of perforations on the analysis of pressure and derivative responses. The results presented are derived from a 3D analytical model. In this model, it is possible to consider nonuniform distribution of perforations and each perforation may have different penetration length and skin factor. It is shown that convergent flow into perforations significantly influences the early-time flow characteristics. In addition to discussing transient behavior, the effect of perforations on productivity is also discussed.
Wax Precipitation in Gas Condensate Mixtures
Authors: Nichita Dan Vladimir , Goual Lamia , Firoozabadi Abbas 
Published: December 2007

Abstract
Wax precipitation for gas-condensate fluids was studied in detail using a thermodynamic model. It was found out that the precipitated wax phase can exhibit retrograde phenomena similar to that in gas condensates. As a result of pressure decrease (at constant temperature) the amount of the precipitated wax may increase first, then decrease and increase again.
The effect of pressure on wax precipitation from gas condensates was also studied. It often shows an opposite effect in wax precipitation from liquids. However, the pressure effect is not universal.
The model used in this work accounts for both the Poynting correction term and the solid-state phase transitions. Incorporation of these effects reconfirms the suitability of multisolid phase for wax precipitation calculations (both the onset and the amount).
Natural Gas Supply Situation (September 1975)
Authors: DeLaMater Stephen T. 
Published: December 2007

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

Abstract
This paper briefly reviews the significance of the gas industry as an indispensable source of energy for each of the residential, commercial and industrial sectors. It discusses the nature of the energy/natural gas shortage and its causes. The basic reason for the shortage is almost universally conceded to be the misapplication of federal regulation of the wellhead price of gas, but impeding solutions to the problem are misconceptions as to the feasibility of alternatives. Specifically, there has been unwarranted reliance on conservation, overly optimistic expectations with respect to "exotics", and apparent bias, on the part of some government decision makers, toward "all electric". Also discussed are factors that will affect future trends in fuel usage, the importance and availability of natural gas supplementals, the economic impact of an extended severe gas shortage, the need for increased new gas exploration, and the case for deregulation, including its economic impact on the consumer. This paper concludes that there must be a national imperative for a continuity of our gaseous fuel supply.

SIGNIFICANCE OF THE GAS INDUSTRY
Natural gas remains the least understood of all of our energy sources. We became dependent upon it almost overnight after WW II because of its sudden abundance at low cost, and because of its premium qualities of cleanliness, versatility and efficiency.
Today people are frankly surprised when they finally come to understand the pervasive ross of its use. Natural gas and its related supplementals provide over 31 percent of the primary energy used in the United States; over primary energy used in the United States; over 41 percent of the nontransportation energy used; more primary energy than any other source produced domestically (41 percent gas, 30 produced domestically (41 percent gas, 30 percent oil, and 23 percent coal); 17 percent percent oil, and 23 percent coal); 17 percent of our national electric power generation; nearly 50 percent of all industrial energy; and 42 percent of the residential and commercial market. Natural gas heats 39.4 million homes and 56 percent of all dwellings. It is the largest single fuel source for the residential, commercial, and industrial markets.
New Through-Tubing Gravel Pack Techniques
Authors: Shurtz Glenn C. , Comeaux Bob G. 
Published: December 2007

Abstract
Production of formation sand continues to be a major operating problem for Production of formation sand continues to be a major operating problem for the petroleum industry, particularly in the geologically young and poorly consolidated reservoirs of the Gulf Coast area.
Remedial through-tubing gravel-pack installations have been greatly simplified through the use of specially designed setting tools and a highly viscous, cross-linked polymer, gravel-carrying fluid. Based on field data, this technique or design application has been highly successful. The term gravel or gravel packing herein is intended to mean any matter used as a packing material. packing material

Introduction
Recovery of oil and gas from poorly consolidated sand formations continues to be a major challenge to the petroleum industry. Sands is usually entrained in fluids produced from such formations, causing equipment erosion and surface handling problems. Often sufficient volumes of sand will enter the production string to completely block or severely restrict fluid flow, making production impossible or prohibitively expensive.
In reservoirs where sand production is a problem, economic production of oil and gas cannot be achieved without some mechanical method of sand control (gravel pack, prepack or chemical consolidation). When a formation is known to produce sand, some measure of sand control should be included in the initial completion. However, in many cases, formation characteristics are not known and wells are completed without sand control. Sometimes these wells produce for months or even years before sand production becomes a problem. Consequently, hundreds of wells in the Gulf production becomes a problem. Consequently, hundreds of wells in the Gulf Coast area are currently sanded up and off production. Many will remain off because of the prohibitively high cost of a major rig workover to pull the production tubing and install sand control. This is not a new problem, and for years the industry has attempted to perfect through-tubing sand-control techniques as an economic means of returning these wells to production. Some limited degree of success was obtained with both production. Some limited degree of success was obtained with both through-tubing chemical consolidation and gravel-packing methods. Because of the high failure rate on completion and the limited life associated with chemical consolidation processes, a harder look was again taken at through-tubing gravel packing.