bluuebunny/crossref_metadata_2025 huggingface dataset:
Fibre Optics Improving Deepwater ROV Pipeline Inspection
Authors: MacGregor D
Published: December 2007

Pipeline inspection is a complex test requiring a variety of sensors, a typical array being illustrated in Fig. 1.

The trend in recent times has been to fit, simultaneously, all of the above sensors to a vehicle in order to maximise data collection from the pipeline in a single pass. This data is then processed in real time as the ROV travels the pipeline. Thus, a chart representing all the available data can be made available shortly after completion of a dive.

The current generation of ROVs uses umbilicals containing various combinations of power conductors, co-axia and twisted pairs to carry the sensor data. These umbilicals, however, have inherent disadvantages which become apparent as sensor data increase in quantity and complexity. This disadvantage is the incompatibility of required high quality-data being transmitted to the surface and the large amounts of electrical energy demanded by the vehicle. Another disadvantage is the incompatibility between sensor signals in terms of frequency and power. However, to eliminate these problems, and to provide for future developments in ROV technology, the new generation of ROVs utilise fibre-optic conductors, the advantages being that they are immune from electro-magnetic interference, they offer wider band-widths with lower power losses {typically 5 dB or less per km) than conventional copper conductors, and are easier to handle as umbilicals lengthen due to demand for vehicles to reach greater depths. Typically, these new umbilicals will be 1.5 km in length.
The Fatigue Resistance and Hysteresis of Man-Made Fibre Ropes
Authors: Parsey M R
Published: December 2007

Data on the fatigue life of man-made fibre ropes is updated and the various mechanisms of rope fatigue discussed.

One of these mechanisms, internal hysteresis heating, is examined a little further. Such internal heating should be unimportant in cycling polyester and nylon ropes at non-resonant periods over 24 seconds and at loads of up to 50% of break.

But internal temperatures sufficient to cause internal degradation in initially wet size 24 ropes cycled to 28% of break for 24 hours at wave period are predicted from simple theory which agrees well with existing data on smaller ropes.

Operators working in such extreme conditions should bear this in mind in defining hawser construction and material.
Case History of Large-Volume Fracture Stimulations in a West Texas Waterflood
Authors: Ilseng J. R. , Cortez M. J.
Published: December 2007

A very successful fracture stimulation program in a mature West Texas waterflood is documented in this paper. Amoco's Anton Irish Clearfork Unit (AICFU) has undergone a 100 well fracture stimulation program since 1979 which has resulted in significant increases in oil production.

Hydraulic fracturing has gradually evolved over the years at the Anton Irish field due to experience gained in new stimulation techniques. Fracture stimulations in the 1970's involved pumping 105,000 gallons of gelled water with 65,000 pounds of 20-40 mesh sand at rates as high as 200 barrels per minute. Although nearly all were initially successful, production increases were sometimes not sustained, due possibly to the insufficient amount of sand/proppant utilized in hydraulic fracturing large 400' dolomite pay sections. Fracture stimulations since 1979 have involved pumping 200,000-300,000 pounds of 20-40 mesh sand in 90,000150,000 gallons, of cross-linked gelled water at 50 barrels per minute (concentrations as high as 14 pounds of sand per gallon of fluid) to create propped fractures which have resulted in sustained production increases from the affected wells. One hundred eighty days after the workover, average per-well production increases of 38 B0PD yielded payouts of 3-1/2 months.

This paper will specifically address fracture stimulation results, quality control measures, and mechanical considerations in beam or electrical submersible pumping equipment, as well as post appraise the economics associated with the $8 million program.
Case History: A Multizone Tight Gas Completion Technique for the Blocker Cotton Valley Field, East Texas
Authors: Hinn R. L.
Published: December 2007

A case history relating to the testing and selection of a multizone completion technique applicable to tight gas sand reservoirs is detailed. This "Bridge Plug Separation" technique (BPS), developed for use in the low permeability Cotton Valley formation of East Texas, has for this operator, proven to be an efficient means of maximizing multizone gas production.
An Industry Perspective: A Case for Optimism
Authors: Miller John R.
Published: December 2007

I WELCOME THIS OPPORTUNITY TO ADDRESS A GROUP OF PEOPLE WHO ARE KNOWLEDGEABLE ABOUT THE PETROLEUM INDUSTRY AND INTERESTED IN THE FORCES SHAPING ITS FUTURE. THE SOCIETY OF PETROLEUM ENGINEERS CERTAINLY FITS THAT DESCRIPTION.

THE ACTIVITIES OF THIS SOCIETY AND THE COLLECTIVE EXPERTISE OF ITS MEMBERS HAVE SERVED THE INDUSTRY WELL FOR MANY YEARS. AND I'M SURE WILL CONTINUE TO DO SO.

MUCH OF OUR INDUSTRY'S STRENGTH STEMS FROM THE PRACTICAL APPLICATION OF ADVANCED TECHNOLOGY, SUCH AS THAT EXHIBITED AT THIS CONFERENCE. IN FACT, THE VALUE OF THIS EVOLVING STATE-OF-THE-ART TECHNOLOGY WILL ULTIMATELY BE DETERMINED BY THE EXTENT TO WHICH IT CAN BE APPLIED TO THE CHALLENGES THAT LIE AHEAD. SUCH IS THE ROLE OF THE ENGINEERS HERE TODAY -- AND A VITAL ROLE IT IS.
In-Situ Production Cost Model for Uranium
Authors: Toth G. W. , Larson W. C.
Published: December 2007

In a recently completed research project for the U.S. Bureau of Mines -Twin Cities Research Center, a computerized costing procedure for uranium in situ leach mining was developed by the NUS Corporation. This costing procedure, termed a cost model, employs a process engineering approach for estimating total project costs as well as equipment and manpower requirements for uranium in situ leaching operations in either Texas or Wyoming. The Bureau recently added the capability to apply the model for New Mexico deposits. NUS also provided consulting support for this modification. Both capital and operating costs are generated by the model along with the overall production cost/pound U3O8 subject to a known rate of return. Conversely, rate of return on equity can be solved for, subject to a given price of yellowcake.

During the course of the research effort, sensitivity tests were conducted for numerous key parameters to determine the cost influence attributable to incremental changes in parameter values. The results of these sensitivity tests along with a description of the in situ leaching cost model have been documented as Bureau of Mines, Mineral Research Contract Report No. J019912, "Cost and Sensitivities Analysis for Uranium In Situ Leach Mining," dated March 1981. An update of this report was subsequently prepared by the Bureau entitled "Improved Solution Mining Production Cost Model," dated September 30, 1982. This update contains the modifications required for application of the model for New Mexico deposits.

In the remainder of this paper, the various features and capabilities of the cost model will be highlighted, along with a review of the sensitivity analysis findings.
Computerized Well Planning for Directional Wells
Authors: Hodgson Harry , Varnado S. G.
Published: December 2007

This paper describes the use of computers for planning the trajectories of deviated wellbores and for monitoring the position of the well during the drilling operation. The model can be implemented on a small (64 Kb) mini-computer. The equations for the model are presented, along with the plots generated. Available plots include vertical and horizontal sections of the wellbore, traveling cylinder plots for anti-collision analysis, and plots that compare the planned wellbore trajectory with the actual surveyed trajectory. In addition, a new directional drilling simulator is described that allows the simulated drilling of a directional well. The simulator is currently in use as a training aid. However, it can also be used for engineering applications. The simulator is interactive and some sample results from the simulator are presented.
The Impact of Potential Offshore California Crude Oil Discoveries on Refineries and Markets
Authors: Seaburn J. T.
Published: December 2007

This paper defines and discusses a number of significant factors which will influence the disposition of future production of crude oil from off-shore Santa Barbara leases currently under development.
A Laboratory Study of the Effects of Hydraulics on Hole Erosion
Authors: Gaylord E. W.
Published: December 2007

Laboratory studies were made with fluids containing bentonite and microcellulose fibers to determine the relationship of Theological variables to borehole erosion. The primary objective of the study was to observe hole erosion that results from purely hydraulic effects. The study was made by circulating fluid through a hole in a specimen made of compacted ground shale. The results of the investigation show a relationship between erosion, fluid wall shear stress, and plastic Reynolds number.
The Use of Weight on Bit, Torque, and Temperature to Enhance Drilling Efficiency
Authors: Guillen G. E. , Lesso W. G.
Published: December 2007

Today, most drilling efficiency decisions are based on models describing downhole drilling conditions. The inputs to these models have in the past been a collection of surface measurements. Measurements While Drilling (MWD) provides realtime information from near the bit and allows for a more comprehensive understanding of downhole drilling conditions. Downhole measurements can help eliminate uncertainties in the behavior of the drilling system, and provide a more scientific approach to improving drilling efficiency.

The downhole drilling measurements include: weight on bit and torque measured by strain gauges set in a drill collar; temperature measured by a sensor on the outside of the collar; and mud flow rate interpreted from the MWD alternator output. Comparison of these measurements with surface data reveals previously unexpected trends that can help diagnose problems. The interrelationships among these measurements lead to a better understanding of the drilling process, and can help make immediate decisions concerning drillstring washouts, bit balling, packed off drilling assemblies, severe dog legs, the overloading of polycrystalline diamond compact bits, and the pulling of worn bits, resulting in direct savings of rig time.
From Geopressured Aquifer Test Well to Commercial Gas Producer: A Case Study
Authors: Doherty M. G. , Randolph P. L. , Poonawala N. A.
Published: December 2007

A short test of a geopressured sandstone produced brine resulting in a decision to abandon the well as a dry hole. The pressure, temperature and salinity of the zone led to additional testing as a Department of Energy (DOE) sponsored geopressured-geothermal "Well of Opportunity." A series of three drawdown and two buildup tests were performed over a two week period. Accurate and continuous measurement indicated a monotonically increasing gas-water ratio (GWR) during the first 24-hour flow test. This change was accompanied by a relatively high and increasing natural gas liquid (NGL) content in the gas. After a total of 9 days of production during a 14-day period, the GWR increased from about 37, SCF/STB (6.7 m3/m3) to over 320 SCF/STB (57.6 m3/m3) with production of about 1.0 MMCE/D (28 636 m3/d) of gas containing 135 BPD (21.5 m3 /d) of NGL, 75 BPD (11.9 m /d) of 40° API (0.83) crude oil and 3150 STB/D (501 m3 /d) brine. More than 33 months after this test, the well was still a commercial hydrocarbon producer.

It appears that the well was a near miss in the context of exploration for a gas cap. Careful measurement of the variations in the produced GWR plus variations in the relative abundances of hydrocarbon species demonstrated a potentially valuable tool for the early detection of the close proximity of a gas cap to a well that produces only brine. Computer simulation with a radial coning model provided an appropriate history match when a greater sand thickness was assumed. Production projections indicated that the reservoir could produce substantial quantities of hydrocarbons over time at a constant 1000 BPD (159 m3/d) or 2000 BPD (318 m3/d) brine rate. Actual production values are in reasonable agreement with the projected figures even though a number of problems caused erratic production and a rather simplistic model interpretation was made.

A productive offset well has been drilled. It is doubtful whether this offset would exist had the initial well been a "dry hole."
Fracture Design with Time- and Temperature-Dependent Fluid Properties
Authors: Poulsen D. K. , Lee W. S.
Published: December 2007

The proppant transporting ability of most hydraulic fracturing fluids is both time and temperature dependent. A proppant transport model that considers this dependence and the fluid temperature variation throughout a fracturing treatment has been devised. This model provides the basis for a numerical method to aid in selecting staged gel and gel stabilizer concentrations.
Downhole Density of Heavy Brines
Authors: Krook G. W. , Boyce T. D.
Published: December 2007

Heavy brine completion fluids decrease in density with increasing temperature and increase in density with increasing pressure. Pressure-volume-temperature (P-V-T) analysis of various brine solutions at temperatures from 76° to 345°F and pressures of 0 to 22,000 psig has been used to examine the behavior-of brine density under bottom-hole conditions. Information obtained from these measurements allows the engineer to calculate more precisely the brine density at the surface which will provide the desired hydrostatic gradient for formation pressure control at downhole temperatures and pressures.
The Application of Depth of Formation Damage Measurements in Predicting Water Injectivity Decline
Authors: Todd A. C. , Somerville J. E. , Scott Graham
Published: December 2007

Pressure maintenance by sea water injection is part of many offshore field developments. Experiences gained over the last decade in the North Sea, where there is a wide variance in the systems used, appears not to have clarified design specifications.

The paper describes various approaches to analysing water quality criteria with reference to water injection schemes and presents the philosophy of the interrelated approach of laboratory experiments, theoretical models and well injectivity predictions in relation to reservoir characteristics.

Results are presented from a laboratory and modelling investigation of permeability impairment as a function of the depth of invasion. A pore network model is described which is generated from laboratory derived pore size distribution data. Predictions of permeability from the model are compared to experimental values and good agreement is demonstrated. The incorporation into the model of particle capture mechanisms enables it to be used to predict the reduction in permeability of a core arising from injection fluids. Another modelling approach is described where the contribution of pore size to permeability is demonstrated.

Water quality experimental results are presented showing permeability profiles obtained using a multiport pressure tapped core holder which demonstrate local permeability impairment as a function of particle size and rock properties.

The results of one modelling approach is applied in the paper to the prediction of well injectivities and filtration requirements.
Aqueous-Based Remedial Treatments for Reservoirs Damaged by Oil-Phase Drilling Muds
Authors: Goode D. L. , Berry S. D. , Stacy A. L.
Published: December 2007

Wells drilled with oil-phase muds are subject to severe damage due to loss of mud filtrate or whole mud to the reservoir matrix or hairline fractures. It is essential that this mud be removed prior to well production in order to gain maximum productivity. A system of aqueous-based remedial treatments has been employed to remove oil-phase drilling muds from damaged reservoirs. Mud solids are suspended and viscosity is permanently lowered by the aqueous-based system so that the mud can be flowed to the surface. Special surfactants restore the affected reservoir to a water-wet state and clay stabilizers prevent formation damage. The new system represents an improvement over conventional hydrocarbon/mutual solvent treatments. The conventional treatments do not effectively suspend mud solids and only temporarily reduce mud viscosity, while leaving the treated reservoir in an oil-wet condition. The aqueous-based system also lowers surface injection pressure below that required by hydrocarbon/mutual solvent systems.

Laboratory data are presented showing the relative effects of the aqueous-based system and a hydrocarbon/mutual solvent treatment on the degree and permanence of oil-phase mud viscosity reduction. The aqueous-based system more effectively and irreversibly lowers mud viscosity as compared to the hydrocarbon/mutual solvent treatment. Cores damaged by oil-phase mud filtrate or whole mud were treated with either hydrocarbon/mutual solvent or the aqueous-based system. Regained core permeabilities following the treatments indicate that the aqueous-based system yields significantly higher recoveries than the hydrocarbon/mutual solvent treatment.

The aqueous-based system has been widely used in wells drilled with oil-phase muds to effect significant production increases. The aqueous-based remedial treatments have more effectively removed damaging oil-phase mud filtrate and solids than conventional hydrocarbon/mutual solvent treatments. In the process, problems associated with the use of hydrocarbon/mutual solvent treatments have been alleviated. These problems include high pumping pressures, "regelling" of the mud, oil-wetting of the formation, and incomplete removal of mud solids.
Dewatering a Deep Gas Well With a Gas Lift System—A Case History
Authors: Green R. E. , Korzekwa C. R.
Published: December 2007

A characteristic of Fusselman gas wells in the Permian Basin is that they begin to produce connate water early in the life of the well. Eventually the water entering the wellbore cannot be unloaded because the hydraulic pressure of liquid fall back becomes greater than the reservoir pressure and the well ceases to flow. At this watered out and nonflow state, considerable gas may remain in the formation. This case study deals with the development of a closed loop gas lift system designed to unload water.

The gas lift system consists of: a predetermined number of gas lift valves externally mounted on mandrels and installed in the tubing string, surface processing equipment, and a gas compressor. Dewatering of the well is accomplished by injecting gas down the tubing-casing annulus and through the gas lift valves. The injection and dewatering process continues until the reservoir pressure overcomes the hydrostatic head. At this point the well will kick-off and flow. To maintain this flowing condition, a portion of the well stream is diverted and reinjected into the well to maintain high velocities in the tubing. The high tubing flow rate lifts the water and reduces the dynamic pressure gradient in the tubing.

The well in this study is currently producing in the above manner. Restoration of gas flow in this well required thirty days due to the uniqueness of the project and modifications through trial and error. Since then, the well has stabilized with a sales volume of 1,100 Mcf/D (31,500 m3/d) and gas lifts 350 barrels of water daily (55 m3/d). An injection volume of 400 Mcf/D (11,455 m3/d) maintains high tubing velocities and prevents the well from loading with water. An increase in reserves has resulted from gas lifting this nonproductive well.
System Survey for Improving Injection Efficiency
Authors: Crow C. L. , Keeling R. E.
Published: December 2007

Injection water quality is a primary factor affecting the ease with which water can be injected into a reservoir and the overall success of a waterflood operation. Proper water quality can also keep waterflood maintenance costs low by reducing the amount of remedial work normally required on injection wells. Most injection systems if properly designed minimize oil carryover and solids content. Water conditioning prevents scale deposition, reduces solids, and allows recovery of carryover oil, resulting in minimum injection pressures. The type of water conditioning process necessary is determined by equipment evaluation and water analyses (including compatibility predictions and membrane filter testing).

Equipment evaluations, such as retention time studies that determine vessel residence time, describe the current mechanical operation of the system. Water analyses and compatibility studies predict the probability of scaling, corrosion, and solids formation occurring within the system. Membrane filter tests are performed to determine the type and amount of suspended solids contained in the water. From these tests, proper water conditioning techniques are implemented. All data should be gathered throughout the system to detect changes occurring between the water source(s) and the injection wells. Changes in such factors as pressure, temperature, and dissolved solids influence problem development.

Graphic representation of data, such as oil concentration (ppm) versus time (days) of a particular vessel's influent and effluent, assists in setting and meeting objectives for injection water quality. Special analyses, such as core flow tests and filtration studies, also define cost-effective solutions to problems.
Principles of Squeeze Cementing
Authors: Goodwin K. J.
Published: December 2007

Squeeze cementing is, by historical definition, the application of differential pressure across a cement slurry to accomplish the process of cement dehydration. The primary purpose of the dehydration is to create immobility of the cement slurry until some compressive strength can be developed. Current cementing technology and additives have improved the process sufficiently that the term "squeeze" may no longer be applicable. It is felt that "Remedial Cement Placement" may be more appropriate, and may more accurately define the process.

The success of a remedial cementing operation depends on a finite definition of the existing problem and the results expected from the operation. If the purpose of the squeeze is not definable, a squeeze job may not be necessary. Significant completion dollars are wasted annually on unnecessary squeezes, poorly designed squeeze slurries, and/or improper slurry placement. Many of the various applications of squeeze cementing may be classifiable as one purpose, i.e., repairing the primary cement sheath to isolate producing intervals and protect the casing string. Proper placement of a low-water loss cement slurry, at minimal surface pressure, into the casing-open hole annulus can satisfy most requirements of squeeze cementing. Initial breakdown pressures and pump-in rates prior to squeeze operations should be conducted at less than Bottom Hole Fracturing Pressure, (surface pressure [or ISDP] + hydrostatic pressure = bottom hole frac pressure). This will insure the placement of the slurry into the annulus, not into the formation. High pressure squeezes are not required, and are in fact, discouraged.

Placement of large volumes of cement slurries into the formation via created fractures, natural fractures, vugs, or zones with worm holes seldom satisfies any squeeze performance criteria; including improvement of GOR, WOR, or isolating a zone for stimulation (block squeeze). If the initial breakdown and pump-in test cannot be performed at sub-fracturing pressure, the cement sheath is competent and the squeeze operation is not required.
Gas Well Deliverability Improved By Planned Fracturing Treatments
Authors: Waters A.B. , Tinsley John M.
Published: December 2007

Publication Rights Reserved

This paper was to be presented at the 40th Annual Fall Meeting of the Society of Petroleum Engineers of AIME, to be held in Denver, Colorado, October 3–6, 1965, and is considered to an abstract of not more than 300 words, with no illustrations, unless the paper is specifically released to the press by the Editor of the Journal of Petroleum Technology or the Executive Secretary. Such abstract elsewhere after publication in the Journal of Petroleum Technology or Society of Petroleum Engineers Journal is granted on request, providing proper credit is given that publication and the original presentation of the paper.

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.

Deliverability from thousands of gas wells has been improved materially by hydraulic fracturing. Both flowing rate and wellhead pressure frequently increased substantially. In many cases production following treatment has been several fold greater than that obtained upon initial completion. Where it has been possible to make detailed study of well data and plan treatments based thereon, results have been quite gratifying. Specific study of cores from individual wells has provided better information for selection of more appropriate fracturing techniques, procedures and chemicals.

Different factors are discussed which should be considered in pre-planning fracturing treatments and some field examples are cited.

Introduction

Estimated natural gas reserves in the U. S. A. at end of 1964 are reported to be in excess of 290.500 MMcf/D. This represents more than a two-fold increase in the reserves reported 20 years ago even though the marketable production has more than tripled in the same period of time. A large part of the increase in reserves has been in the past 16 years, since hydraulic fracturing was first introduced. Commercial success of a given well is dependent on the rate of deliverability at specified drawdown pressures and the period of time such deliverability can be maintained. Improved deliverability derived by fracturing bas made it possible for many wells and fields previously considered non-commercial to be converted into profitable ventures. Not only have production rates been increased. but frequently wellhead pressures have been increased several fold. These factors have a direct relationship with open flow potential.

Past experience has specifically indicated that planned or designed treatments for gas well formation conditions and reservoir characteristics have materially increased the success ratio. Although hit-or-miss treatments have been successful. consistently good results have not always been obtained. This paper will review and bring together many of the factors which a gas well operator should consider in planning a fracturing treatment to obtain improved deliverability.
PDC Bits Find Application in San Joaquin Valley
Authors: Fox J. P. , Wood J. E.
Published: December 2007

Polycrystalline diamond compact (PDC) bits have been successfully and economically used to drill sand and shale sections in the oilfields of the Southern San Joaquin Valley of California. "Successful" refers to reducing the number of days to drill a well by four to six days, and "Economical" refers to reducing the cost per foot for the sand and shale intervals drilled with PDC bits.

Enhancements of design variables including variations in back rake and side rake angles, and improved selection (numbers and sizes) of nozzles have helped PDC bits be economical in the Southern San Joaquin Valley.

In addition to conventional vertical wells, PDC bits used in conjunction with mud motors and steering tools have also been successfully used to directionally drill wells in this area.
Diagnostic Tools for Mapping California EOR Processes
Authors: Leighton A. J. , Wayland J. R.
Published: December 2007

In recent years techniques using wave properties have been developed or adapted for measuring fluid injection fronts in assisted oil recovery processes. Also, tracer and pressure transient tests are being used increasingly to track and diagnose problems in these processes. This paper, summarizing the companion paper, "Diagnostic Tools for mapping EOR Processes," briefly describes each technique and its strengths and weaknesses. Conditions for most advantageous application are given.

The chief considerations in selection of a suite of mapping and diagnostic techniques for an EOR project are discussed. The selection process is illustrated by three hypothetical examples which are typical for operations in larger California oil fields.

The techniques are most effective when used in combinations and in conjunction with all other reservoir information available.
A Systematic Approach for the Effective Log Analysis of Tight Gas Sands
Authors: Kukal G. C.
Published: December 2007

A new log interpretation system called TITEGAS has been developed to analyze the reservoir characteristics and producibility of tight gas sands. The system is based upon equations which define the response of conventional logging tools. A basic log suite of density, neutron, and resistivity are the only logs required by the system, however TITEGAS also allows for utilization of various other logs including photoelectric effect, spectral natural gamma, micro-resistivity, microwave travel time, dielectric constant and acoustic travel time.

The new system includes several innovative analytical procedures: A technique to compute porosity in zones having variable gas saturation and clay content.A new method to quantify gas saturation in the zone investigated by the density and neutron tools.An improved method using the gamma ray to determine clay content in compacted sands composed predominately of illite-type clays.An improved method to determine clay content from the sonic and density log when illite is not the dominant clay type.A new non-geometric mathematical model using neutron and density logs to calculate clay content. This equation makes it possible to refine the clay log response constants.A new technique for the interpretation of formation water resistivity. This procedure is useful in thick sand-shale sequences where water salinity is variable.New methods to refine matrix density of the reservoir. Matrix is dealt with as a foot-by-foot variable rather than as a constant.A new technique to analyze invasion profile and qualitative formation permeability.New methods to detect natural fractures through the the modeling of logs that are generally available.

The TITEGAS system is applied to the DOE/Sandia MWX wells. Comparisons are made between the TITEGAS system results and the high-quality core data and well test data from these wells. The comparisons indicate that the system is a powerful new procedure for the analysis of tight gas sands.
F-Pairs vs. Devonian Shale
Authors: Streeter R. W. , Sabin A. W.
Published: December 2007

Use of F-overlays to evaluate air-drilled Devonian shale wells simplifies recognition of subtle variations in log response between productive and nonproductive intervals. Combinations of F-curve overlays, called F-pairs, are plotted on a logarithmic grid and normalized in an interval thought to be unfractured. Anomalous response behavior becomes useful in choosing fractured intervals.
Tight Gas Resource and Technology Appraisal: Sensitivity Analyses of the National Petroleum Council Estimates
Authors: Brashear J. P. , Rosenberg J. I. , Mercer James
Published: December 2007

In 1980, the National Petroleum Council (NPC)1/ published the most authoritative and comprehensive estimates to date of the technical and economic potential of tight sands gas.

While the NPC study remains the landmark effort on this subject, its estimates for recoverable natural gas are considered by many to be optimistic. The Gas Research Institute (GRI) and the Department of Energy (DOE) jointly commissioned construction of the Tight Gas Analysis System (TGAS) as a vehicle to perform systematic sensitivity analyses of the NPC study, to serve as a repository for future additions to the data base and analytical understandings of the technology, and to estimate the benefits of specified R&D advances. This paper describes TGAS briefly, demonstrates its reconciliation with published NPC results, and reports sensitivity analyses of: ∘Improved fracture effectiveness with and without closer well spacing;∘Producing from gas-bearing lenses encountered by the wellbore versus lenses lying remote from the wellbore; and∘Altering the NPC's assumptions about the relationship between reservoir permeability and thickness.

The reconciliation and sensitivity studies confirm the analytical integrity of the NPC study but also point out that the NPC's results contain significant uncertainties.
Test of Secondary Gas Recovery by Coproduction of Gas and Water From Mt. Selman Field, TX
Authors: Rogers L. A.
Published: December 2007

A previously watered-out and abandoned gas reservoir in the Sub-Clarksville formation of the Mt. Selman field in North East Texas was reentered and secondary gas recovery initiated by pumping of water. Pumping was done with a sucker rod pump and bottom hole pressures in the producing well and a nearby observation well was measured via gas filled capillary size tube extending into open ended larger tubing downhole. Numerical modeling to match past performance and project possible future production was done before and during the field test to compare theoretical and actual production results. A series of draw-down and build up tests over a three month period were performed to evaluate the reservoir and determine its potential for secondary gas recovery. No residual gas cap of mobile free gas was found. The remaining free gas was apparently trapped as an immobile dispersed phase within the reservoir rock matrix. The amount of gas dissolved in the reservoir brine was about 7 Scf/Stb (1.28 std m3/m3). The produced gas/brine ratio varied from 7 to 25 Scf/Stb (1.28 std m3/m3 - 4.5 std m3/m3) indicating that some immobile gas was mobolized by pumping water to lower the reservoir pressure. Gas analysis has shown the trapped free gas to be richer in heavier hydrocarbons than the dissolved gas.
Application of an Alternate Stimulation Method for the Ferguson Sandstone in the Powder River Basin
Authors: Smith K. T. , Schmid J. C.
Published: December 2007

Due to the high degree of fluid sensitivity in the Ferguson Sandstone formation of the Empire and Iberlin Fields, Campbell County, Wyoming, an alternate fluid-less completion technique was sought. Conventional stimulation methods utilizing acids and water or oil based fracturing fluids were considered inappropriate due to the possibility of creating additional formation damage through the release and transport of various fines, and the possibility of creating flow channels or fractures which could allow nearby water to be produced.

The alternate method used, utilizes a (solid fuel) charge of progressively burning propellant in order to create channels of improved permeability from high temperature, high velocity gas expansion. This was attempted on fairly low productivity wells and general preliminary results indicate immediate production increases and/or improved decline rates. These are just preliminary results and an overall evaluation of this method is currently on-going.

The purpose of this paper is to present the application of, and the immediate results from, this new stimulation method. In doing so, this paper attempts to provide the industry with an evaluation of the usefulness and economic feasibility of this alternate treatment method. This may lead to conjectures concerning additional areas, if any, for the profitable application of this device.
Successful Alternatives to Conventional Cement Designs in the Williston Basin
Authors: Bryant G. A.
Published: December 2007

Since mid-1981, 36 wells have been cemented in the Williston Basin with a cementing system diametrically opposed to conventional cementing designs used for bonding across massive salt members. Since implementation, along with the use of relaxed invert emulsion oil mud, not one casing problem has arisen in the wells where these systems were used.
Numerical Simulation of Diamond-Bit Drilling With Air
Authors: Memarzadeh F. D. , Miska Stefan
Published: December 2007

A simple mathematical model of diamond bit drilling, which accounts for diamond wear is applied for simulating bit performance. The model predicts the influence of weight on bit, rotary speed and bit rotating time on instantaneous rate of drilling, footage, bit wear and cost. A heat transfer model is presented. By application of drilling and heat transfer models, a minimum volumetric air flow rate required for sufficient bit cooling is determined.
Bit Optimization for Positive-Displacement Motors
Authors: Dyer R. S.
Published: December 2007

The basic nature of drilling with a positive displacement motor is different than that of conventional rotary drilling and often necessitates different decisions regarding bit choices and recommended operating parameters. For best results, separate bit optimization studies and recommendations should be prepared during the planning stages of a well for possible motor runs. Several factors should be considered in determining bit choice and bit configuration. Many of these factors are used in selecting bit type, such as rock bit, diamond, or polycrystalline diamond bit. Other factors determine choice within a specific bit category, as well as choices in hydraulics parameters and performance expectations.
Reducing Energy Costs for Heated Uintah Basin Crude Oil Transport
Authors: Schuster D. S. , Irani C. A.
Published: December 2007

Energy costs associated with transporting heated waxy, high pour point crude oil were reduced. Storage and shipment temperatures were lowered for truck transport; and concave trace tubes were used to improve heat transfer from hot trace fluid to crude oil flowlines. Chemical pour point depressants were evaluated, but their use was not economically attractive.
How To Stabilize Clays and Improve Injectivity
Authors: Sloat B. F. , Larsen Dan
Published: December 2007

New technology based on the use of potassium hydroxide to permanently "fix" clays in the near well-bore area is taken from the laboratory development status to the field. Injection well treatments using KOH are compared with the normal soak (potassium chloride) and coat (cationic polymer) approach in the same reservoir.
A Case Study of Electrical Submersible Pumps in the Q-1 Block, Dutch Sector
Authors: Williamson D. R.
Published: December 2007

The Q-l Development represents the first commercial oil production from the Dutch sector of the North Sea. Electric submersible pumps were chosen as the primary form of artifical lift for this development. This paper discusses the approach Union Oil Company of the Netherlands has taken in the installation of electric submersible pumps. Average run lives in excess of seven months have been experienced, with many units still operational after fifteen months of service.
Remotely Operated Vehicles as Underwater Inspection and Maintenance Tools: An Operator's Viewpoint
Authors: Simpson J.
Published: December 2007

Utilisation of remotely operated vehicles in the Northern North Sea is tending towards a science. Various vehicles compete in a razor-sharp market for jacket and pipeline inspections, drilling support and diver assist roles. This paper discusses Conoco's Northern Operations viewpoint and their vehicle utilisation experience.
Lessons Learned from the Lena Guyed Tower
Authors: Finn L. D. , Maus L. D.
Published: December 2007

The design, fabrication, and installation of the Lena guyed tower required the development of new offshore technology in several areas. Lessons learned from this experience include an understanding of the consequences of major design decisions and insight into the interactive behavior of the structural components. The guyed tower is now a proven deepwater production platform concept for the Gulf of Mexico and is also judged to be applicable for a wide range of water depths and deck loads in the North Sea and other areas of the world.
The Fundamental Issues in Future Field Development Concepts (100 to 250 Metres Water Depth)
Authors: Wray C. R.
Published: December 2007

The fundamental issues in future field development concepts in the 100m to 250m water depth range with particular reference to the North Sea comprise the traditional elements of reservoirand location characteristics, products delivered and overall economics, combined with the need to seek more cost effective solutions to smaller, potentially marginal prospects. This requiresminimum facilities design, as applied to conventional techniques, to be compared with the potential application of novel concepts, for which a high level of confidence must be established intechnical feasibility and achievement of projected costs and schedule. Both approaches can onlybe adequately assessed through increased effort during the pre-engineering and conceptual design phase prior to commitment to the preferred development option.
Markets Technologies and Strategies for the Offshore Supplies Industry
Authors: Crichton D. , Wilson J. M.
Published: December 2007

The continued growth expected in world offshore activity will create opportunities for a technology based and export-oriented supply industry. This paper is based on a research programme undertaken by the Scottish Development Agency over 1983-84, and identifies the scale of world markets and the technologies most likely to enable exploitation of them. It goes on to establish the need for Government and industry to adopt a selective research and development strategy aimed at improving UK capability in the critical technology areas, and considers the implications of failing to implement such a strategy.
A Microprocessor-Based Steam Generator Quality Controller
Authors: Anderson J. L. , Falke S. E. , Clum D. N.
Published: December 2007

The measurement and control of steam quality is a key factor in the operation of a steam stimulated enhanced recovery project. This paper is presented to discuss the development of a microcomputer based monitoring and control system which has proved effective in field applications.
The Design of Buoyant Ball Sealer Treatments
Authors: Gabriel G. A. , Erbstoesser S. R.
Published: December 2007

The success of well stimulation treatments is often strongly dependent on selective placement of treating fluids into low permeability or damaged zones and away from high permeability or undamaged zones. A previous investigation conclusively demonstrated through laboratory and field tests that buoyant ball sealers can provide highly effective diversion. Buoyant balls have been shown to exhibit 100% seating efficiency provided they can be transported down the casing to the perforations.

A field-tested design methodology has been developed to maximize and optimize the benefits realized from the use of buoyant ball sealers. Positive-displacement ball injectors effect reliable introduction of buoyant balls into the treating fluid, and ball catchers have been designed and used to recover the balls following the treatment. In lieu of ball retrieval, the controlled-density ball sealer process can be employed in which the balls are buoyant in the treating fluids but are nonbuoyant in any subsequently produced or injected fluids. Calculation of ball and fluid transport times to the perforations determines minimum job/stage volumes and ball injection schedules. Buoyant ball sealer technology can be applied in ultralow flowrate treatments by the use of a special transport technique in which the balls are confined at the interface or in the mixing region formed by two fluids of different densities. Similar fluid staging techniques promote highly effective ball sealer diversion in deviated wells by neutralizing the gravity force and by minirnizing the ball-to-perforation travel distance. All of the objectives of a multicomponent, multistage, sandstone acidizing treatment can be accomplished by strategic placement of buoyant ball sealers in one or more of the various treating fluid stages.
A Reserves and Economic Analysis Program for Microcomputers
Authors: David A. , Carson G. P. , Vo T.
Published: December 2007

This paper describes the formulation and operation of a Reserves and Economic Analysis program written for micro-computers. The program was constructed as a template to be used with spread-sheet software. The version being discussed in this paper uses a popular commercial software program called 1-2-3* which was written for the 1MB-PC** or compatible machines.

Being a spreadsheet template, this program can be converted to other software and/or hardware systems. It also offers the user a high degree of formatting flexibility, which can be used to create customized in and/or output for specific purposes. Other advanced facilities available in 1-2-3 such as "Self-Explanatory" Menu and "User-Defined-function" Macro make the program user friendly.

The logics and instructional equations of this program is relatively compact and efficient in terms of hardware requirements, processing speed and accuracy.

This program can be utilized for most projects that involve reserves and economic analysis, for it offers many of the options available on much larger commercial packages. Some of these desirable options include a third phase of production, automatic scheduling of the decline rate and the production stream, two payout conversions in cumulative dollar or volume of the primary phase, changing secondary and/or tertiary phase(s) to primary phase ratio and manual inputting.

The economics of the system, whose cost includes the minimum hardware and software requirements, are also discussed by comparing the cost of running numerous cases on this system versus runs on a commercial timeshare system.

The program will be in the public domain. Its listing and an operator manual can be obtained through the authors or the Energy Engineering Department of First City National Bank of Houston for the distribution cost.
Design and Impact of a Real-Time Drilling Data Center
Authors: Isaacs W. R. , Bobo J. E.
Published: December 2007

A computer enhanced telecommunications system has been jointly developed by a major operator and a service company to provide real-time data acquisition and back-up surveillance of drilling operations. A continuously manned central Data Center links the experience and talents of office, rigsite, and technical personnel to provide immediate cost-effective decisions. Benefits include: (1) significant cost per foot reductions; (2) potentially hazardous, costly problems minimized or eliminated; (3) management and experienced staff personnel involvement in critical well decisions using real-time data; (4) a real-time and historical database for use with drilling optimization programs and (5) a means for generating morning reports, invoices, inventory, and cost-control between rigsite and office personnel. Case histories demonstrating the above benefits are presented from several areas.
Micellar/Polymer Flood Shows Success in Bell Creek Field
Authors: Hartshome J. M. , Nikonchik J. S.
Published: December 2007

In February, 1981, a 179-acre micellar-poiymer project was initiated in the Bell Creek Unit ‘A’ Muddy Sand reservoir, Powder River County, Montana. Employing nine injector-centered 20-acre five-spot patterns and utilizing Union Oil Company's Uniflood™* micellar-poiymer process, the "TIP" project is projected to recover 39.6% of the post line-drive waterflood oil-in-place, with a total project tertiary recovery of 1.574 million barrels of oil. It is further expected to generate $14 million in total net profit for the Unit ‘A’ Working Interest Owners prior to reaching its economic limit in 1988.

Installed under the U. S. Department of Energy's "Tertiary Incentive Program," the TIP project provided a second chance to test the micellar-poiymer technology in the Bell Creek Field, and was able to improve dramatically on the marginal performance of the original 160-acre Micellar-Polymer Pilot located 3.6 miles to the north.

The remainder of this paper discusses in some detail the history, the design and implementation, the operation and the performance evaluation of this highly successful project.