bluuebunny/crossref_metadata_2025 huggingface dataset:
Well Control Experiments related to Slim Hole Drilling
Authors: Steine O.G. , Rommetveit R. , Maglione R. , Sagot A.
Published: December 2007

Well Control Experiments related to Slim Hole Drilling.

During June 1994 slim hole well control experiments were performed in an inclined onshore research well in Stavanger, Norway. The tests were gas kick, annular pressure loss and surge/swab experiments.

A total number of 36 kicks were performed during these experiments. In addition we did flow tests circulating the well at various flow rates with and without rotation. The pressure loss effects of rotation on flow were logged. Tests in both plain drilling water and muds were done. Surge and swab pressures were logged downhole when reciprocating drill pipe at various tripping speeds.

Raw data files containing approx. 110 Mbytes in ASCII files of downhole pressure data, and surface data have been gathered for further analysis. The data was of high quality and provide opportunities to improve existing well control procedures and to incorporate this knowledge into future drilling operations.

This paper summarises the experimental conditions during which data were recorded, main results and some operational recommendations.

Experimental parameters such as influx type (liquid/gas), gas concentration, kick injection rate, mud flow rate, drillstring rotation rate, pipe reciprocation etc. were varied. Three kick detection systems and one flow meter were tested during the experiments.

Introduction

Well control is very critical during slim hole drilling, due to the importance of the annulus pressure loss as well as the small mud volume in the well.

Operations like pipe rotation, reciprocation, tripping etc. may generate high transient pressures in the well. Unwanted influxes and fractures may be initiated also.

The effect of rotation on the frictional pressure loss in an annulus has been studied experimentally.

Well control and hydraulics have been studied experimentally in full scale previously. An experimental programme for studying annular pressure losses and surge-swab pressures in oil based muds has been performed. Full scale kick experiments in both OBM and WBM in an inclined research well have also been reported. Experiments to validate kick control and pressure loss predictions have been performed in a slim hole test well. Tests related to continuous coring has also been reported.

A number of well control issues for slim hole drilling have been studied experimentally in a full scale research well. The well, which is 2020 m long with 63 deviation, was heavily instrumented both on surface and downhole.

P. 101
Application of High Pressure Dual Tubingless Completions and Low Cost Concepts in an Environmentally Sensitive Area
Authors: Holub Leo D.
Published: December 2007

Maximizing project economics through reduced drilling and completion costs is a major industry goal that challenges us for innovative ideas and risk consideration. Presented is a case history of the application of dual tubingless completions for high pressure Wilcox formations that require fracture stimulation. Low cost modem approaches to design and selection of equipment and services as well as associated risks are discussed. The project area is located in a residential housing development in a major city and also penetrates a sensitive subsurface gas storage operation. The project was highly successful without any loss to safety or the environment.
Coiled Tubing Window Milling
Authors: Hearn D. D. , Blount C. G. , Kamlowsky P. E.
Published: December 2007

Reliable, low cost coiled tubing window milling technology has become the cornerstone of ARCO Alaska's coiled tubing sidetrack program at Prudhoe Bay. ARCO began to investigate coiled tubing drilling technology in 1989. The program grew into an aggressive field application of this technology, with over thirty wells drilled in the last 2 1/2 years. The program's first window was cut below production tubing with a coiled tubing bottom hole assembly (BHA) in the fall of 1994. To date, 14 wells have been sidetracked using this technique.

The windows are cut off of a specifically formulated cement plug without the use of a whipstock. Reliability, always high, has continued to improve, while the cost and time required continue to come down. ARCO has been able to reduce sidetrack costs by an average of 40% compared to conventional sidetrack methods through the continued evolution of coiled tubing drilling technology, of which window milling is a part1. This window milling technique should also have the potential to save time and money in slim hole and conventional drilling applications as well.
Jack-Up Diverterless Drilling—The East Kalimantan Experience
Authors: Doré E. E. , Vlack R. L.
Published: December 2007

A surface hole diverterless drilling method, utilized on a jack-up drilling unit, has been successfully implemented offshore East Kalimantan, Indonesia. Variations of the diverterless drilling method have also been utilized on 72 wells drilled from platform and floating drilling units offshore East Kalimantan. The diverterless drilling method provides an enhanced risk management tool superior to conventional offshore surfacc hole drilling. This method maximizes personnel safely and minimizes risk to property and the environment. The method also provides an ancillary cost savings. The evolution of the diverterless drilling method, the practical application for jack-up implementation and the benefits of diverterless drilling are detailed herein.
A Study of Polymer Solution Rheology, Flow Behavior, and Oil Displacement Processes
Authors: Nouri Hossein H. , Root Paul J.
Published: December 2007

Flow and displacement theories for non-Newtonian polymer solutions in porous media have not been advanced to porous media have not been advanced to nearly the extent as those for the Newtonian fluids. At present, the field and experimental data available pertaining to the flow mechanism of pertaining to the flow mechanism of polymer solutions through porous media, polymer solutions through porous media, albeit reliable, are not comprehensive nor complete. Both experimental and theoretical research in development of a more satisfactory theory to describe the flow behavior of polymer solutions in porous media are urgently needed.

Laboratory experiments were performed to study the role of mobility performed to study the role of mobility ratio for a process in which oil is displaced from a porous medium by a polymer solution. A reduced friction polymer solution. A reduced friction factor-Reynolds number correlation is developed to predict the flow of various polymer solutions through consolidated porous media and a theory is advanced to explain more truly the flow behavior of a polymer solution as it passes through the cores.

The cone and plate viscometer data obtained for a total of 88 solutions of twelve different polymers more frequently used by the petroleum industry appeared to fit the power law equation quite well. The effects on solution viscosity of temperature, sodium chloride concentration, polymer molecular weight and polymer concentration are also discussed.

Introduction

Among the methods of secondary recovery which have been developed is one which involves the injection of high-viscosity water into the reservoir to improve the mobility ratio and thereby increase the displacement efficiency. The mobility ratio, when two immisicible fluids displace each other, is defined as the ratio of the mobility of the displacing fluid to that of the displaced fluid:

displacing M = (1)displaced

The mobility ratio is a very important factor in secondary recovery predictions, governing the recovery efficiency of the oil by the displacing fluid. A mobility ratio of greater than one will result in an uneven and an inefficient displacement and a poor oil recovery.
Effect of Specimen Size on Rock Properties
Authors: Singh Madan M. , Huck Peter J.
Published: December 2007

Triaxial tests were conducted on two rock types using specimens ranging from 2 inches to 32 inches in diameter to determine the influence of specimen size on strength and mechanical properties. properties. While the influence of specimen size on mechanical properties was small, the effect on strength and character of failure was pronounced. Although sufficient data to verify statistical failure hypotheses was not collected, it is hoped that additional work now in progress will help in the development of more realistic models.

Introduction

Reduction of rock strength with increasing specimen size is a well known phenomenon which is of concern to those who deal with rock masses. Failure hypotheses have been advanced relating to both the statistical occurrence of macro-flaws (weakest link theory) and to the total available stored energy in the mass.

Most of the work to date in this connection has been conducted on confined specimens in the laboratory and related to measurements taken in the field. This has included empirical relationships based on the performance of mine pillars as well as the application of fracture mechanics. Triaxial tests have been performed mainly for the purpose of studying rock behavior under purpose of studying rock behavior under confining stress, and have been conducted with small specimens. No previous triaxial tests on the scale reported in this paper have been conducted to the best of the authors' knowledge. It is evident, therefore, that the current state of the art is qualitative rather than quantitative, and requires considerable effort in the future.
Electro-Chemical Purification of Hydraulic Pump Power Oils
Authors: Hettick Larry , Lucas Roy
Published: December 2007

The first commercial application of a new process for the purification of power oils has been in operation for a period of two years at production facilities operated by Long Beach Oil Development company. Evidence for the success of this installation is summarized in analytical data regarding the removal of water, particulate matter and water-soluble particulate matter and water-soluble salts from the make-up oil to the closed power oil system. of more interest is the sustained performance of the system itself - there has been a 50% decline in make-up oil requirement and a 70% reduction in engine repair costs since installation of the new process. process. Data from the precursory laboratory tests, the semi-works scale field prototype, and the commercial (1,500 B/D) prototype, and the commercial (1,500 B/D) installation are presented; of special interest is the information on the particle-size distributions of the particle-size distributions of the particulate matter in the oil. Detailed particulate matter in the oil. Detailed descriptions of the performance of the system, before and after the installation of the power oil treater, are included as are daily logs of the critical system parameters. Information comparing the parameters. Information comparing the performance of this new process with performance of this new process with those previously employed to remove impurities from power oils is also summarized.

Introduction

Erosion and wear of down-hole engine parts are often attributed to the presence of finely divided particulate matter present in the particulate matter present in the power fluid. Unfortunately, there power fluid. Unfortunately, there is relatively little information available regarding the nature of these solids or of correlations between their properties and engine maintenance. Although it seems desirable to remove the abrasive materials, there are few guide lines regarding design and performance of various systems which performance of various systems which could be used to clean these solids from power fluids or of the maintenance cost reductions which can be expected from such removal. The paper presented by Phelan before paper presented by Phelan before the 1953 Fall Meeting summarizes previously available information. previously available information.
Lithology and Fluid Properties and Their Relations to the Distribution of Saturating Fluids in Sandstones
Authors: Holmes M. , Dreher K.D. , Eloy A.J.
Published: December 2007

Cores from the Robinson sandstone, Crawford County, Illinois, were examined to investigate rock/saturation relations. Capillary pressure/ saturation data were obtained on the same suite of cores with fluids of different interfacial tensions using the centrifuge technique. The cores in every case were highly water-wet. Petrographic examination of core plugs as well Petrographic examination of core plugs as well as thin sections indicated that five basic pore groupings were present, on the basis of grain diameter and size and degree of interconnection of the visible pore structures.

Since deposition, the sandstone has undergone considerable pore modification by secondary post-depositional (diagenetic) processes. These have involved some pore processes. These have involved some pore enlargement but mainly porosity plugging accompanied by an increase in pore tortuosity. This history of secondary change can be seen in the way in which fluids saturate the rocks.

From the capillary pressure data, pore entry size distributions were determined, from which average pore entry size and a pseudo surface area term were calculated. Relations between these parameters vary with pore geometry. Evidence is presented which suggests that, at irreducible saturation, the wetting phase coats the rock surface as a uniform layer phase coats the rock surface as a uniform layer as well as blocking small pores. Data are presented which show that permeability is more presented which show that permeability is more closely related to pore entries at the large end of the distribution curve, rather than an average pore entry.

Introduction

Comparison of porosity (phi) with water saturation (Sw) has been used for many years to describe reservoir behavior. Archie indicated in a qualitative manner that net pay will depend upon how water saturation varies with porosity. He showed that the relationship between phi and irreducible water saturation (Swi) reflects the pore size classification. Following Archie's classification, mercury capillary pressure data were used, in conjunction with routine log analyses, to estimate oil-occupied pore space. Others have indicated that examination of phi versus Sw as a function of depth is of value to establish probable producing fluid and water mobility in probable producing fluid and water mobility in various zones of carbonate reservoirs.

In 1958, Weaver noted that phi x Swi is equal to a constant for homogeneous carbonates in which the matrix is essentially uniform.
Application Of The Wireline Formation Tester
Authors: Conrad K.M.
Published: December 2007

Introduction

The Formation Tester, a wireline tool for safely and rapidly testing formations in the open hole, was introduced to the oil industry in 1955. Since its inception, it has proved to be a valuable evaluation tool. It provides a wireline method for obtaining an actual sample of formation fluids substantiated with formation pressure recordings.

Application of wireline testing has been extended to cased-hole testing, and improved in the open-hole testing of hard formations by the addition of the Formation Interval Tester. Thus, testers are currently available for use in almost any possibly productive zone — whether that zone be in open hole or behind casing/hard formation or soft.

Open-hole tests can be run in hole sizes of 6 to 12–1/4" in diameter under a hydrostatic pressure range of 500 to 20,000 psi. Cased-hole testing is available for casing sizes of 5–1/2 to 13–3/8" O.D. Fluid samples of 1, 2– 3/4 or 5–1/2 gallons may be recovered.

The purpose of this paper is to discuss the applications of these testers and the inter-pretation of their recoveries.
The Comparable Efficiency of Mathematical Techniques Used in Reservoir Simulation
Authors: Traylor C. , Sheffield M.
Published: December 2007

The results of this work compare the computing efficiency of several mathematical methods which can be used in solving the equations governing reservoir fluid flow. Two-dimensional, water-oil movement in a vertical cross-section and in two areal reservoirs are considered as examples. The fluids used are slightly compressible and both gravitational and viscous forces are considered. The mathematical techniques considered are successive line overrelaxation; block Jacobi, semi-iterative; iterative and noniterative alternating direction implicit; the strongly implicit procedure; symmetric successive line overrelaxation, semi-iterative, and line Saul'Ev.

A new method is presented for comparing "equal quality" results. Basically, this involves the determination of a correlation of quality in a material balance-type term vs quality in solving the equations, the L2 norm. The conclusions of this work disagree with reports in the literature in some respects. These differences are attributed to the fact that a compressible fluid system was considered in this work. Results indicate that geometry and fluid properties affect the convergence rates of iterative techniques. Furthermore, noniterative techniques require extremely small time steps to produce the same quality solutions as iterative techniques produce.

Introduction

The use of reservoir simulators to predict field performance has become widely accepted by the petroleum industry in the past decade. Engineers use both iterative and noniterative techniques to obtain approximate solutions of linear equations which described fluid flow. Variational methods are presently being investigated. With the increased used of reservoir simulators, means of reducing the computer time required to make field studies are needed. Indeed, the amount of computer time required to solve a particular field problem may vary tenfold, depending only on the mathematical method used.

This investigation is concerned with comparing the computational efficiency of solution techniques of finite difference approximations to the equations describing reservoir fluid flow. Iterative methods are discussed in detail and noniterative methods are briefly considered. Iterative procedures usually require a set of parameters to speed convergence to an acceptable parameters to speed convergence to an acceptable answer. These methods are of little value to the engineer unless a reliable procedure for choosing effective parameters is known. Where possible, this investigation makes use of possible, this investigation makes use of programmed algorithms to compute parameters programmed algorithms to compute parameters internally in the reservoir simulator.
Formation Evaluation by Linear Programming In the Presence of Errors and Uncertainty
Authors: Ramsey Terry L. , Helander Donald P.
Published: December 2007

A proposed solution is presented for the evaluation of formation lithology, saturations and heterogeneities in the presence of errors. A general linear model was constructed capable of using all the available information. This model is indeterminate and requires a formalized decision-making process to evaluate the most likely formation properties. The indeterminate problem is solved by maximizing an index which problem is solved by maximizing an index which gives appropriate weight to experience and minimizes errors.

After a solution has been achieved, further analysis is possible for the investigation of the stability of the solution, for an indication of the quality of the data, and for a definitive evaluation of the influence experience has upon the final solution.

Examples of the solution are given for both mineral and petroleum evaluation.

Introduction

As a result of a series of analyses of the interpretative process necessary for the determination of formation properties, a number of techniques, usually computer implemented, have been published. However, because of major simplifying assumptions and a failure to recognize the requirements of the decision-making process which must consider experience, none of the solutions was entirely satisfactory. Experience is the quality which makes one solution more acceptable than others under otherwise identical qualifications.

In the early development of analytical models for formation evaluation, a simple lithology was considered which could be described by linear equations in a fully determined system. These models were extended to allow the inclusion of geological information and an arbitrary number of logs to evaluate more complex lithology. These solutions were useful; but, for cases of limited information or for complex lithology, the problem was indeterminate and could not be problem was indeterminate and could not be solved. Recognition of the indeterminate problem forced the examination of the solution problem forced the examination of the solution criteria and the objectives of log analysis. These problems were further accentuated by the recognition of possible errors in the log measurements.

The problem considered is determination of the most likely representation of the formation properties as described by well logs. The properties as described by well logs. The approach to the problem was to set up a mode that considered the physical characteristics within the limitations of the errors associated with the measurements. Any information expressed as an equality or as a limit was utilized.
The Effect Of Temperature And Pressure On Wave Velocities In Porous Rocks
Authors: Mobarak S.A. , Somerton W.H.
Published: December 2007

The interpretation of sonic logs from deep, high temperature reservoirs is complicated by lack of data on the effects of temperature and pressure on sonic velocity and the relation of these effects to pore properties. In the present work, dilatational wave velocities were measured for several sandstones and were found to decrease by as much as ten percent when temperatures were raised from 68F to 392F. This could result in over-estimation of porosity by nearly one-third. A temperature and pressure correction chart for interpretation of sonic velocity data is proposed.

Introduction

Improvement in drilling techniques and the consequent drilling of more deep wells have given rise to problems associated with the high pressures and high temperatures encountered in deep wells. Temperatures approaching 400F and pressures exceeding 10,000 psi are becoming common, leading to problems with drilling fluids and with the running of logs. In addition, the behavior of subsurface formations becomes more complex at these extreme conditions. For correct interpretation of logs run under these conditions, knowledge is needed of the effect of temperature and pressure on the property being deduced from the log data. An example with which this paper deals is the effect of high pressures and temperatures on elastic wave velocities in rocks and the relation of these effects to sonic log interpretation. The literature contains theoretical analyses and test results which indicate that elastic wave velocities increase with increasing pressure. Test results show that the rate of increase in wave velocities is higher at lower pressures than at higher pressures. This increase is attributed to closing of microcracks within the rock and to increase in grain-to-grain contact area with pressure.
Application of Recent Advances in the Mechanics of Sand Consolidation
Authors: Harrisberger W.H. , Coulter A.W. , Gurley D.G.
Published: December 2007

A complete shut-off of sand flow in producing wells can be attained and high success producing wells can be attained and high success ratios are possible. Successful sand control using sand consolidation plastics depends on complete coverage of the zone with a resin that will leave the formation well consolidated with the highest retained permeability. In addition, the consolidated formation must retain its strength for many years. The materials and techniques to accomplish these objectives are available.

Sand consolidation plastics have been in use since the early 1940's with varying degrees of success. Over the years there have been many improvements in the materials used, but these improved materials have not significantly changed the success ratios. It is now recognized that well completion and workover methods and job performance are probably more important than the performance are probably more important than the type or quality of resin used. In the past few years, many added improvements have been made in methods, materials and techniques. This paper will point out these improvements.

The completion techniques that will be covered are selection of perforated interval and perforation density. The job performance techniques covered will be cleaning of perforations, clean fluids, clean tubular goods, injection rates and pressures and zone isolation. Of prime importance are the considerations for prime importance are the considerations for consolidating dirty formations.

Some of the improvements in plastic systems that will be discussed include special pre-flushes, high-resin-content plastics, coupling agents, and diverting agents.

The overall purpose of the paper is to put together in usable form all the factors that must be considered in planning and performing sand consolidating plastic treatments and to establish guidelines that will lead to higher success ratios in these treatments.

Introduction

The degree of success with sand consolidation plastics is very difficult to measure because of plastics is very difficult to measure because of the wide variation of definition of success. However, a survey conducted by the API Southern District Study Committee on sand control indicated that the overall success ratio for sand consolidation plastics on old and new wells was 76 per cent. This plastics on old and new wells was 76 per cent. This same survey showed that the success ratio for gravel packs with liners was 72 per cent. Success here is packs with liners was 72 per cent. Success here is defined as either producing sand-free or at tolerable sand production.
Simulation of In-Situ Combustion in a Two-Dimensional System
Authors: Smith James T. , Ali S.M. Farouq
Published: December 2007

A two-dimensional mathematical model of the forward combustion process was developed and used for studying the effects of fuel content and air injection rate on the sweep efficiency attained in in-situ combustion. The model incorporates the effects of single-phase gas flow, heat generation by a combustion front, change of permeability in the burned zone, heat transfer by conduction and convection within the reservoir, and heat loss by conduction to the adjacent formations. A numerical scheme was developed to solve the system of partial differential equations constituting the model.

The model was used to investigate combustion in a quadrant of a five-spot pattern. It was found that as the fuel content of the reservoir increases (0.5 to 2.0 lb/cu ft), the sweep efficiency at combustion front breakthrough increases (68 to 84 percent) and tends to reach a plateau. The advantage of a high sweep may be offset, however, by a corresponding increase in heat loss and total air requirement. Sweep efficiency did not show a consistent trend with variation in the air injection rate for a given fuel content.

For a constant air injection rate, the percent heat loss from the reservoir increases percent heat loss from the reservoir increases linearly with the fuel content. Also, for a constant fuel content, the heat loss decreases with increasing injection rate. Feedback of heat from the adjacent formations into the reservoir was observed in the vicinity of the injection wellbore. Based upon the cumulative heat loss, however, this effect was negligible.

Breakthrough time for the combustion front increases rapidly as the fuel content increases. Accordingly, the cumulative air requirement for a project also increases with increasing fuel content.

For a constant injection. rate the peak temperature along the combustion front increases as the fuel content is increased. The temperature at any given point on the front varies in response to the existing fuel content, the magnitude of air flux, and the heat loss rate at that point. For a constant fuel content, the air flux is the factor which determines whether portions of the combustion front will be extinguished, resulting in poor reservoir sweep, high air-oil ratios, and economic failure.

Introduction

In-situ combustion is a highly promising oil recovery technique that has been tested under a wide variety of conditions. Up to now, however, a complete mathematical model of this complex process is lacking.
Pulse-Testing Method for Measuring Thermal Properties of Solids
Authors: Fairchild J.W. , Woods E.G.
Published: December 2007

This paper describes a new technique, thermal pulse testing, for the measurement of thermal conductivity, volumetric heat capacity, and thermal diffusivity of solids. Thermal pulse testing is a transient technique which is pulse testing is a transient technique which is analogous to the present technique of pressure pulse testing, a method of obtaining fluid flow pulse testing, a method of obtaining fluid flow properties between two or more wells. properties between two or more wells. Thermal pulse testing is superior in two major ways to other methods of obtaining thermal conductivities, heat capacities and thermal diffusivities. First, several simultaneous measurements of all three properties of a sample are obtained with one test. Secondly, an appropriate method of analysis eliminates any effect of linear temperature changes in the system during the measurement period, and it tends to reduce any nonlinear trends. One such method is described. Also, a measure of precision is obtained from tests made under precision is obtained from tests made under essentially identical conditions.

The method uses a small heater along the axis of a cylindrical sample and an accurate temperature sensor on the midplane of the cylinder at a known radial distance between the heater and outer boundary. Power is input, at a constant rate, to the heater with an alternating on/off pulse, while the resulting temperature response out in the sample is detected with the temperature sensor. The thermal properties are then determined from interpretation charts based on the exponential integral (Ei) solution of the diffusion equation, which assumes that the system is homogeneous with infinite outer boundaries and zero inner radius. Data from nonradial or finite-acting systems can be interpreted with other analytic solutions of the diffusion equation or by numerical regression techniques.

Experiments have been conducted to test the thermal pulse-test technique. The effects of changing pulse length and distance to the temperature probe were considered. Results obtained from a thermal pulse test of a known sample were compared with published values and with results obtained from the same sample by the thermal conductivity probe technique. The results obtained from this new technique compared well with both the published values and the probe technique.

The work described in this paper has shown that thermal pulse testing as a method of obtaining thermal properties is useful and practical.
Modeling High Angle Wells in Laminated Pay Reservoirs
Authors: Fair P.S. , Kikani Jitendra , White C.D.
Published: December 2007

Introduction

Productivity improvement and acceleration projects have gained substantially from the success of horizontal well drilling technology. The successful placement of near-horizontal wells in difficult reservoir configurations has become routine. However, not all reservoir situations are amenable to horizontal drilling. Specifically, laminated reservoirs, such as thinly bedded turbidites in the Gulf of Mexico (GOM), have been perceived as poor targets. Potentially large reserves are locked in these reservoirs. These laminated turbidite systems have zero vertical permeability at the Bouma sequence scale and extremely small kv/kh ratios (kv/kh 0) at the full field, reservoir simulation grid block scale.

In general, a small well count is essential to help minimize development costs. To achieve requirements of both high productivity and small well count, highly deviated wells (80 <90) cutting the entire sand package are desirable. Such well configurations have been known to improve productivity of these wells. However, the deviated well model given by Cinco fails to predict any improvement in well productivity. This apparent paradox is reconciled in this paper.

Bed thickness, well diameter, and well angle control the productivity of these thin-bedded sequences. For wells that are nearly horizontal, a simple technique to calculate the productivity improvement factor (PIF) is derived. The range of validity of this approximation was determined by comparison with fine-grid simulations.

These inflow relationships have been used to construct the well models for simulations of GOM reservoirs. An example application is presented along with specific guidelines to determine the correct well kh as validated by a grid sensitivity study.

Implications of Existing Deviated Well Solutions

Thin-bedded turbidite reservoirs in the deep water Gulf of Mexico are currently being considered for development. These fields contain reservoirs which have bed thicknesses that are on the order of 0.25 inch thick and are separated by very low permeability shales. These reservoirs can be modeled as having no vertical permeability (kv=0). Based on Cinco's deviated well solution, one would not expect high angle wells to perform any better than a vertical well for this situation. This comes directly from the form of Cinco's pseudoskin (S):

(1)

where

(2)

and

(3)

After some further consideration, we have concluded that the line source approximation for the wellbore which Cinco applied, may be the reason that his solution indicates no improvement in thinly bedded reservoirs. We offer an alternative limiting solution.

P. 19
A New Tool for Core Recovery of Soft, Unconsolidated Formations
Authors: Lindsey H.E. , Courter Clay N. , Lebourg Maurice P.
Published: December 2007

This paper describes a new core barrel device for cutting and retrieving subterranean cores, particularly from soft or unconsolidated formations; it utilizes a fluid-pressure collapsible sleeve above the core bit to receive and hold the cored material and permit its retrieval in its original subterranean condition. Pressure responsive valves maintain a fluid pressure behind the collapsible sleeve to retain it in the collapsed position until the core is received in the sleeve and also permit fluid behind the sleeve to exhaust as the core enters the sleeve while the sleeve continues to offer lateral support for the core and also remains collapsed above the core. When the core barrel is withdrawn, a small amount of soft core material may fall from the lower portion of the core barrel and the lower portion of the sleeve collapses to retain the remainder of the core in the core barrel.

This paper describes the operation of the new core barrel and full results obtained in very soft uranium ores in South Texas. Some of these cores were previously unobtainable by former conventional methods. The operation of this tool is quite simple and it can be furnished in small or larger sizes and in varying lengths, permitting its use in areas and fields offshore or land, small or large rigs, shallow or deep, and can be used for the recovery of mineral ores or petroleum sands. Drawings illustrating its potential use in ocean floor sampling are shown.

Introduction

The recovery of soft unconsolidated formation core samples has always been a difficult problem. In the past, conventional coring equipment has been modified by the use of "finger" catchers, traps and other devices to facilitate recovery of such formations. However, there is a need for a simple tool that will not only retain the core when it is retrieved but will support it and prevent its bridging as it is being cored. This new tool should be simple to operate and should be available in different lengths and sizes. It should be adaptable to large and small drilling rigs and operate successfully at any depth on land or water.
The Role Of Oil Mud In Controlling Differential-Pressure Sticking Of Drill Pipe
Authors: Simpson Jay P.
Published: December 2007

Simpson, Jay P., Member AIME

Publication Rights Reserved

This paper is to be presented at the Upper Gulf Coast Drilling and Production Conference of the Society of Petroleum Engineers or AIME in Beaumont, April 5–6, 1962 and is considered the property of the Society of Petroleum Engineers. Permission to publish is hereby restricted 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 should contain conspicuous acknowledgment of where and by whom the paper is presented. Publication elsewhere after publication in 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 or 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 considered for publication in one of the two SPE magazines with the paper.

Published studies of differential-pressure sticking of drill pipe have presented methods of testing mud for tendency to cause wall sticking. One such method has been extended to permit simulation of downhole temperature and mud circulation, and data have been obtained for both water and oil muds typical of those currently in use. The laboratory data indicate an oil mud with good rheology, suspension, and filtration properties (as tested under downhole conditions of temperature and differential pressure) to be a very effective means of combatting differential-pressure sticking.

During the past year oil muds have been used on the Louisiana and Texas Gulf Coast to replace water muds in drilling and completion operations where differential-pressure sticking was a problem. Mud densities have varied from 12.5 to 18.8 ppg, formation temperatures have been as high as 300 F, and well depths have been as great as 16,500 feet. Using adequately conditioned non-asphaltic oil muds, these operations have been conducted with no further difficulty from differential-pressure sticking.

For areas in which differential-pressure sticking has been the primary problem and expense, the use of oil mud has become accepted field practice. Total well costs have been greatly reduced by the elimination of fishing operations and reducing time spent on the well.
Quantitative Measurement of Flow Heterogeneity in Laboratory Core Samples and Its Effect on Fluid Flow Characteristics
Authors: Johnson Carl E. , Sweeney S.A.
Published: December 2007

Flow heterogeneity in laboratory core samples can significantly influence the experimental measurement of reservoir rock flow and displacement characteristics useful in reservoir engineering calculations and in evaluating new oil recovery methods. This variable in laboratory measurements deserves more attention than it usually receives and, although the more extreme causes of flow heterogeneity in core samples such as cracks, voids and obstructions are often easy to recognize, there is need for a more precise method for measuring this kind of heterogeneity.

The method developed and presented in this paper treats the presented in this paper treats the core sample as if it were composed of 50 parallel flow paths. The fluid conductivities of the 50 flow paths are deduced from the results of a simple equal viscosity, equal density miscible displacement experiment performed on the sample, and the performed on the sample, and the pattern of distribution of these pattern of distribution of these conductivities provides a quantitative measure of the degree and character of the flow path heterogeneity present. The paper presents equations for calculating flow path heterogeneity patterns and several examples showing patterns and several examples showing how these measurements can be useful in laboratory experimentation.

Introduction

There is considerable evidence that flow heterogeneity is an important variable in the laboratory measurement of the flow and displacement properties of oil field core samples, and that it may significantly affect the results of such measurements. In spite of the evidence, little attention has been paid to the quantitative measurement of paid to the quantitative measurement of this variable. It is, however, usually agreed that uniform, fairly homogeneous core samples are required if the experimental data obtained is to be useful in reservoir engineering calculations.
Pollution Control in the Alberta Oil and Gas Industry
Authors: Bohme V.E. , DeSourcy G.J.
Published: December 2007

Alberta's Energy Resources Conservation Board was given statutory responsibility for pollution control in the oil and gas industry pollution control in the oil and gas industry in 1970. This paper describes the history and objectives of pollution control in the industry and provides detailed descriptions of the more important pollution control regulations applicable to drilling, producing and gas processing operations.

A brief summary of the size of the industry is given to show its importance in the economy and environment of Alberta. The province's natural environment and its population distribution are briefly population distribution are briefly described to indicate the manner in which drilling and production activities have affected Alberta and its people.

The Board's role in pollution control prior to 1970 is mentioned to show how prior to 1970 is mentioned to show how early pollution control activities developed largely from the application of resource conservation principles.

To allow the industry to work under a single agency as much as possible, the pollution control activities of most pollution control activities of most government departments affecting drilling and producing were transferred to the Board in 1970. The method of integrating the pollution control activities of the departments into the Board is outlined and the continuing relationship between these departments and the Board and the industry is explained.

The Board's objectives regarding pollution control in drilling, producing, pollution control in drilling, producing, gas processing, oil sands processing and pipe line operations are described. A pipe line operations are described. A summary of pollution control regulations indicates the application of the objectives to operations and equipment in the industry.

Schematic figures indicate detailed pollution control requirements applicable pollution control requirements applicable to drilling, producing wells, batteries and gas processing plants.

Introduction

The Province of Alberta is the second most westerly Province in Canada. It is bordered on the south-west by the Rocky Mountains and its physiography ranges from flat prairie in the south and east to heavy forest and rolling bush land in the north and west. The State of Montana lies directly south of Alberta.
Protection of an Aquifer - A Case History
Authors: Owens Willard G.
Published: December 2007

At the request of a Colorado Ground Water Management District Board of Directors, we studied the bedrock aquifers within and in the immediate vicinity of the District. The purpose of the study was to develop bases for the effective and meaningful rules, regulations, and conservation measures to be adopted by the District. Our study included the compilation of data on the deep aquifers to develop an understanding of the suballuvium geologic formations so existing and future water rights can be protected while allowing optimum development protected while allowing optimum development of ground water resources from the deeper aquifers.

The tabulation of municipal, commercial and other significant water supply wells completed in the bedrock aquifers was included in an engineering geologic report.

BEDROCK AQUIFERS

The results of our hydrogeologic study show that there are four significant bedrock aquifers within the District. These are:

Dawson-Arapahoe sands

Laramie sands

Fox Hills sands

Pierre transition zone sands

These bedrock aquifers occur at or near the surface within the District as shown on Plates I and II. These aquifers are made up of sands and sandstones which are interlayered with shale. The dip is toward the south-southeast into the Denver Basin. Plates III, III-A and IV are geologic cross-sections which show how these aquifers occur at depth. These cross-sections also show the correlation of the sands over considerable distances and the manner in which the sands are separated from each other by relatively impermeable shale.

Dawson-Arapahoe Sands

This aquifer occurs in the southwest one-third of the District, as shown on Plates I and II. This aquifer is defined Plates I and II. This aquifer is defined as sands and sandstone, ranging in grain size from fine to very coarse, which overlie the predominantly shale section of the Laramie formation. The Dawson-Arapahoe aquifer occurs from the surface to a depth of approximately 800 feet in the immediate vicinity of Strasburg and approximately 1,200 ft. at the southwest corner of the District boundaries.
The Thermo Tube, A Natural Convection Heat Transfer Device for Stabilization of Arctic Soils in Oil Producing Regions
Authors: Babb Albert L. , Chow David M. , Garlid Kermit L. , Popovich Robert P. , Woodruff Eugene M.
Published: December 2007

A brief mathematical analysis of the heat transfer device is given followed by an experimental evaluation of Thermo Tubes of different geometrical configuration. The capability of these natural convection heat transfer devices to store "cold" in various media and in appropriate structural elements is explored. Mathematical models are described which couple soil enthalpy fluctuations with those of the cold storage media, and include temperature constraints imposed by the ambient air and the soil surface temperatures. These analyses have been applied to the design of specific structures for pipelines and oil wells in which rigid thermal pipelines and oil wells in which rigid thermal and structural requirements need to be maintained year-round, particularly in warm permafrost regions such as Glennallen, Alaska. permafrost regions such as Glennallen, Alaska.

Introduction

This paper describes a natural convection heat transfer device originally devised by Balch, and subsequently modified and applied to provide stabilization of structures in permafrost regions of the Arctic. permafrost regions of the Arctic. A schematic diagram of the Thermo Tube is given in Figure 1 and structural details of the 3-inch and 8-inch tubes are given in Figure 2. In the lower half, heat is absorbed from the surrounding medium which warms the working fluid The warmed fluid rises to the upper heat rejection surface through an inner tube and gives up its heat by conduction and natural convection by means of finned surfaces in the cooler medium. The total thermal capacity of a given tube depends not only on the geometrical configuration but also on the working fluid, the temperature difference between the cold air and the warmer region to be cooled, and the thermal properties of the heat rejection and the heat absorption media. In practice, the ratio of heat rejection area to heat absorption area is about 3:1.