bluuebunny/crossref_metadata_2025 huggingface dataset:
Basic Data for Oil and Gas Wells
Authors: Pepperberg Leon J. , Stephenson Eugene A.
Published: June 2014

The natural gas industry is essentially a byproduct of the oilindustry.

When first discovered the gas was usually regarded as a nuisance, and even whenfound immediately associated with oil, or suspected to be so, it was customaryto blow it freely into the air, in the hope that gas would shortly be replacedby a flow of oil. The early methods of production, transportation, andutilization were neither economical nor efficient; the chief value of gas wasbased on its use as a fuel, with no regard to (1)its effect upon the oil withwhich it was associated, (2) its importance as a lifting agent, or (3) to itspossibilities for the manufacture of byproducts.

The spread of scientific research among major gas and oil companies, manufacturers, and academic groups, has gradually brought recognition of thefact that many of the technical problems bearing on production, transportationand utilization are common to both the gas and the oil industry. A few of theproblems that have received serious study, and from which highly gratifyingresults have been obtained, are:gas measurement,oil well and gas wellcapacity tests,elimination of field waste,design of pipe lines andcompressor stations,extraction of constituents which might interfere withthe normal flow of gas through the line,control of reservoir pressure,estimation of reserves of both oil and gas,control of water encroachment,measurement of factors which influence fluid movement through sands,solubility of gases in oils,effect of dissolved gases upon the propertiesof the solution.

These investigations have demonstrated that almost everyproblem relating to oil production also involves some phase of natural gasengineering.

During the past 15 years the use of experimental methods for the discovery andmeasurement of obscure, influencing factors, which cannot be determined purelyby hydrodynamic or thermodynamic analyses, have contributed much towards theprogress made in solving the problems of the oil and gas industries.
Comparative Resistance of Certain Commercial Ferrous Materials to Corrosion by Gaseous Hydrogen Sulfide
Authors: Devine John M. , Wilhelm C.J. , Schmidt Ludwig
Published: June 2014

A corrosion-testing apparatus which operates in the field and which willdetermine the comparative resistance of various ferrous materials to corrosionby gaseous hydrogen sulfide at ordinary temperatures is described. Theprinciple of the uniform method of testing is to allow natural gas containinghydrogen sulfide, direct from its source in the field, to flow over the groupof specimens for a given period of time, and subsequently to estimate thecorrosion sustained by each specimen by determining its loss in weight. Thecomparative results obtained when specimens of 47 representative ferrousmaterials of described typical composition were tested at ordinary temperatureswith natural gas containing hydrogen sulfide are given in tables showingaverage penetration of metal, inches per year.

The primary purpose of the work was to determine the possible utility to thepetroleum and natural gas industries of ferrous materials that are commerciallyavailable, and no attempt is made to discuss the results of the tests from themetallurgical standpoint. The following is a summary of the resultsobtained:Steels containing 12 to 27 per cent of chromium showed the highestresistance to corrosion. The presence of nickel in these high-chromium steelsdid not affect their resistance.Steels containing approximately 5 per cent of chromium showed comparativelyhigh resistance, but somewhat less than that of the highchromium steels.
Efficient Utilization of Reservoir Energy
Authors: Umpleby Joseph B.
Published: June 2014

The subject of reservoir energy and its efficient utilization has been wellexplored in many papers. The present effort, therefore, is limited to a summaryof existing information combined with an emphasis of the probability that therelative importance of controlling factors will change with advancingknowledge. Consequently the necessity for flexibility in laws and regulations, inherent in the problem, is emphasized.

Definitions

Many terms have been widely used in the literature without having beenspecifically defined. For example, confusion exists in the use of"reservoir energy" and "gas energy." The latter is much morelimited in meaning than the former. Other terms have been variously used.Consequently, I shall preface my remarks with definitions of a few of the morepertinent terms.

Reservoir energy is that force or forces, active or potential, that is nativeto the reservoir and has the power to move oil through the reservoir rock. Theenergy may result from expanding gas, from hydrostatic head, from the weight ofoverburden, or from any other source. Gas energy is the expansive power of gaswhen pressure is reduced. It is one type of reservoir energy.

An oil reservoir is that part of a geologic formation or-formations in whichoil occurs in commercial quantities wholly surrounded by nonproductive rock.The essence of this definition is effective separation rather than remotenessand under it oil reservoirs may be superimposed in the same oil pool.Conservation of reservoir energy means primarily its maximum use in theproduction of oil.

Unit operation is a plan of development and production, which embraces anentire oil reservoir under a unity of engineering control. It is distinct fromunitization, which has to do with arrangements of organization and equities tomake unit operation possible in areas of divided ownership.
An Approximate Theory of Water-coning in Oil Production
Authors: Muskat M. , Wycokoff R.D.
Published: June 2014

The phenomenon called water-coning is that, observed in many oilwells, in which bottom water gradually and frequently suddenly displaces a partor all of the oil production when a certain rather critical production ratefrom the well is exceeded. To follow in detail the process of the formation of a water cone asit breaks through the oil zone and enters the well bore is a problem so complexas to make a theoretical analysis practically impossible. However, ananalytical treatment of the flow system before the water has broken through and during the time thatit lies statically beneath the oil zone with an elevated or "coned"surface can be carried through under certain approximations. To present ananalysis which shows the essential characteristics of the coning mechanism is the purpose of the presentdiscussion.

Physical Basis of Theory and Meaning of Approximations

As will always be true for flow systems where true water-coning is at allpossible, the water will be supposed to lie beneath the oil zone because of itsdensity contrast with respect to the oil. In fact, under the usual fieldconditions, when the pay horizon is reasonably homogeneous, the water mostfrequently enters the well through the lower zones, but even when it entersfrom intermediate zones it may, in the later life of the well, displace thebottom layers of oil, thus resulting in a system wherein the oil is effectivelyfloating on the water.
Some Constitutional Aspects of the Oil Problem
Authors: Bates Henry M.
Published: June 2014

On Feb. 22, 1934, the A.I.M.E. Petroleum Division StabilizationCommittee conducted a symposium in New York City on stabilization of the oil industry.Among those taking active part in the discussion were Messrs. Sidney Swensrud, JosephE. Pogue, W. S. Farish, J. B. Umpleby, H. D. Wilde, W.E. Wrather, Northcutt Ely, E. L. DeGolyer, E. A. Stephenson, Earl Oliver, Amos L. Beaty, Nathan R. Margold, Henry M. Bates and Roscoe Pound. Because of the volume of this discussion it waswithheld from publication in the 1934 annual petroleum volume with the expectation thata special volume on Petroleum Stabilization would be issued during the year inwhich the entire discussion could be published. That was not done. The addresses ofDean Bates and Dean Pound, dealing as they do with broad principles ofConstitutional law, are as timely now as they were when delivered one year ago and arereproduced herein for their bearing on current legislative proposals.

Some Constitutional Aspects of the Oil Problem

Henry M. Bates, Dean of Michigan Law School

Mr. Chairman and Gentlemen: I accepted your Chairman's invitation to speak toa group of experts in this field with the greatest hesitation, because I knowlittle or nothing about it. Certainly I can make no detailed suggestions, orsuggest planning along very definite lines. You cannot do that sort of thing in avacuum, and as I have suggested, my knowledge of the whole oil problem is next tonothing… It is possible that as a student of our public law, constitutional lawparticularly, for a number of years, I have acquired a perspective that may enable me tooffer, for what they are worth, some general thoughts on these problems.

I think that nothing in the whole field of law requires more definitelyand clearly the functional approach than does the problem of a sound legal solutionof the difficulties of the oil and gas industry. The industry is dealingwith substances that are peculiar, and one must know how those substances act andwhat has been the history of the industry, to undertake to make anything likespecific suggestions. I certainly am not qualified.
Modifying the Capture Law
Authors: Oliver Earl
Published: June 2014

DEAN Roscoe Pound, of Harvard Law School, in addressing the A.I.M.E. Petroleum Division on Feb. 22, 1934, said, "When you are able to work out a program that is mechanically feasible, that is economically advisable, and which seems in your judgment, which is just as good as that of anyone, to be politically wise, you will not have very much trouble in the end in inducing the courts of today to find that it is legally sound."

The purpose of this paper is to show: first, legal conditions necessary to promote conservation and stabilization; and second, to suggest operating procedure when those legal conditions are established. The proposal is mechanically feasible and economically advisable. A growing public understanding should make it politically wise.

The disappointing progress in the development of conservation and stabilization can be attributed to the lack of two legal concepts as integral parts of oil and gas law; i.e.,a practical substitute for the capture rule,collective ownership control for the individual oil and gas pool.

When these two concepts are established on an equitable basis, conservation and stabilization procedure will become a comparatively simple process, more or less automatic in its adaptation and operation. Establishing these concepts is the function of the law-making agencies and might well be left to them for discussion except that the mechanical processes that give them form and substance must first be developed by the engineer.
Acre-foot Yields of Texas Gulf Coast Oil Fields
Authors: Deussen Alexander
Published: June 2014

The figures listed in a table for Gulf Coast fields given by L. P. Teas in1934 are so greatly at variance with results that I have obtained from aserious study of this subject over a number of years, that I am disposed tochallenge the correctness of Mr. Teas figures as an accurate representation ofacre-foot yields of Gulf Coast fields, and as regards at least two of thefields listed by Mr. Teas I desire to "put into the record" somefigures that, according to my study, are more nearly in accord with what Iconceive to be the actual facts.

Upon investigation I find that Mr. Teas figures, inadvertently no doubt, arenot what they purport to be. Apparently the figures were arrived at byconsidering as thickness of the producing formation the net thickness ofproducing rock corresponding" to the total of the net portions of theproducing zones which actually yield oil into the drill hole"-and infollowing this method I am under the impression that Mr. Teas was acting underinstructions of the Institute in the preparation of this paper, in order to getcomparable figures from the several fields of the United States. Apparently theauthor interpreted these instructions to mean that in the absence of coredthicknesses of producing horizons the actual number of feet of screen set inthe various producing zones was to be taken as the basis for arriving at thethickness of these zones and the" acre-foot" yields.

It is obvious that in many instances only 20 ft. of screen, or even 10 ft. ofscreen, might be set in a well, when there might be actually 100 ft. of oilsand present. In the early operations in the Gulf Coast it was usual to setmuch less screen than the amount of sand. It follows that the" acre-footyields" so arrived at would be much greater than those found by using thefull amount of sand.

In Mr. Teas table, it was indicated that up to the end of 1933"acre-foot" yields had been obtained in the several fields as listed inTable 1.
Economics and Well Spacing in Texas
Authors: Hubbard William E.
Published: June 2014

During the last decade the known reserves of petroleum in the United Stateshave increased from about five billion to over thirteen billion barrels. Fromthe standpoint of public welfare the existence of these known reserves presentsan undeniably favorable picture, but viewed from the position of many aharassed operator the blessing has not always been considered an unmixedone.

Along with this increase in excess reserves, curtailment of production has comeinto being as a matter of necessity and the principle of proration as a matterof equity. As a practical matter it has been considered necessary to curtailthe production of old wells as well as that of new wells in a pool. The rightof new pools to produce has been recognized, and the allowable for them hascome partly from increased market demand and largely from the allowablesalready enjoyed by the developed pools. The natural result-a downward trend indaily per-well allowables-has been especially felt by Texas operators. Thistrend may be illustrated by Table 1, which comprises the five active areas inTexas, and from which may be noted the following:The average daily allowable per well has decreased about 53 per cent inthree years.Of the 184,000-bbl. increase in total allowable for the five areas, 29,000bbl. came from the increase in state demand and 165,000 from the combinedallowables of the remaining pools in the state.
Desalting Crude Oils
Authors: Egloff Gustav , Nelson Edwin F. , Maxutov C.D. , Wirth Charles
Published: June 2014

The treatment of emulsified crude oils has been a problem for years in thepetroleum industry. Until comparatively recently various methods of settlingwith and without chemicals have been used with indifferent success. Since wellshave been acidized, emulsified crudes have been produced, which addconsiderably to the need for improved methods of treatment. The presence oflarge quantities of salts in the oils from acidized wells has presented severalnew problems to the industry. The use of hydrochloric acid in well treatmentshas caused the formation of sodium, magnesium, and calcium chlorides byinteraction with the dolomitic limestones. These salts dissolve readily in thewater normally present in the oil, and they. are therefore incorporated in theemulsified oil. The crystalline salts have also been found in the oil, prevented from settling by protective films such as asphalt, resins andpetrolatum. In some instances, free hydrochloric acid has been found. The saltsmay be present in crude oil in amounts ranging from a few pounds to over 1000lb. per 1000 bbl. of oil.

The transportation of these crude oils through pipe lines has led to erosiveand corrosive effects, which are a tremendous cost to the petroleum industry. During 1937, more than 1,200,000,000 bbl. of crude oil was transported throughpipe lines. Of this quantity approximately 10,000,000 bbl. was water, andconsiderably more than 50,000,000 lb. was salts. If the crude oils were treatedat the producing wells to remove the salts and water, an appreciable savingwould be possible. The treatment would not be difficult, since it has beenfound that these oils are more easily treated at the time they are producedthan after the aging and more stable emulsification that occur before theyreach the refinery. Since great costs are involved in the use of.these saltycrudes at the refinery, treated oils essentially free of salts would naturallycommand a premium.

The real added costs lie in refining salt-containing crude oils. Severecorrosion of refinery equipment in both topping and cracking installations hasappeared in many refineries.

T.P. 915
Surface and Interfacial Tensions of Oil-water Systems in Texas Oil Sands
Authors: Livingston H.K.
Published: June 2014

The first person to investigate intensively the vast field of surfacephenomena and capillary effects was the eminent English scientist, LordRayleigh (1842–1919), who laid down most of the fundamentals of this subject.This work was greatly amplified by Irving Langmuir, who, in connection withresearch for the General Electric Co., spent 25 years on the study of thesurface chemistry of films, finally receiving the Nobel Prize in Chemistry for1932 in recognition of his work. At present, William Harkins, of the Universityof Chicago, is the world's foremost authority on surface-tension measurementand his independent work, when combined with that of Langmuir, resulted in theorientation concept of solubility and surface activity, which is now animportant fundamental in chemistry. The theory laid down by these men was firstapplied to practical considerations regarding petroleum reservoirs by F. E.Bartell, of the University of Michigan, in connection with an AmericanPetroleum Institute research grant. The latest and most advanced application ofBartell's work is contained in an article published in 1935 by Allen Garrisonof Rice Institute, in which he relates Bartell's measurements to the ratio ofoil to water produced by wells and shows the types of petroleum reservoirswhere the effects studied by Bartell are significant. This article is intendedas a minor extension of such work.

Method

The experimental work of this investigation involved determination of theviscosity of crude oil, specific gravity and surface tension of the crude oiland of connate water occurring with those oils, and interfacial tension betweenthe oil and the water, which occurred together. Because the volume of oil inmany of the samples was small, it was necessary to use the Ostwald pipette fordetermining viscosities, rather than the more familiar Saybolt universalviscosimeter.

T.P. 1001
Recent Advances in Knowledge of the Colloidal Properties of Clay Suspensions and Gels
Authors: Reed Charles E.
Published: June 2014

With the increasing importance of clay in drilling operations which demandmore precise and exacting control over its behavior, there has come therealization that most of our present methods of control over many of itsimportant properties still represent more of an art than a science. Such asituation with respect to a material of such industrial significance isunfortunate, and naturally many investigations have been conducted to improveour knowledge. In general, these investigations have revealed the complexnature of clay behavior and while sometimes they may not have seemed tocontribute directly to a solution of the field operator's problems they havebeen of inestimable importance in bringing to light the broad fundamentalscientific principles upon which must be based any effective working theorycorrelating the known facts of clay behavior and predicting profitable newlines of attack for its improvement.

Major Facts Concerning Behavior of Clays

In the study of clays, as in that of most other colloidal materials, it hasbeen impossible to make progress by the study of isolated facts. On the otherhand, analysis of large groups of facts, many of which seem at first completelyunrelated, can lead to a deeper insight into the structure of clays and themechanism of their behavior. It will be well to list the major facts on whichthe analysis here presented is based, starting with those that have emergedrepeatedly from past investigations and which thereby constitute an impregnablefoundation upon which must rest any comprehensive theory of claybehavior:Clays consist of hydrated aluminosilicates of extremely fine and variableparticle size.Suspended in water, clays exhibit variable degrees of swelltng, dependingupon their origin and upon the chemical and colloidal nature of any othersubstances present. The magnitude of the swelling is a direct indication of theextent to which the clay has become dispersed.

T.P. 871
Intensive Weighting of Petroleum Drilling Muds with Galena
Authors: Gross Henry Emmitt
Published: June 2014

Recently, areas of abnormal rock pressure have been drilled on the Gulf Coast of the United States. These pressures may be caused by the recent andpronounced raising of some of the structures without loss of the formationpressure that existed when the reservoir was developing and the producing sandmuch more deeply buried. It is possible also that a permeable fissure mayconnect a shallow accumulation of gas with the gas cap of a much deeperreservoir of oil, gas and water. The pressures are so great that dependence onblowout-prevention equipment alone is hazardous to life and property.Fortunately, wells with excessive casinghead pressures, such as the StanolindOates No. 1 of the South Houston field, an 8700-ft. gas well with 6000 lb. persq. in., and the near-by Stanolind Candelari No.1, and 8100-ft. gas well with5000 lb. per sq. in., have not blown out and cratered. A case is on record ofdrill pipe i.n a well in Harris County, Texas, (Oates No.1) rotating for 8 hr.through blowout-prevention rams holding a back pressure of 2900 lb. per sq. in.at the casinghead after the mud was altered by salt-water intrusion. Suchconditions warrant the use of extremely heavy muds having low viscosity, madefrom galena (PbS) or specially prepared mixtures of hematite (Fe20s) and galenasuspended by bentonite.

In some Gulf Coast wells, sodium silicate mixed with concentrated brine is usedto drill through heaving shale formations. Such a fluid inhibits heavingremarkably, but it is expensive and? costs as much as $10 per barrel. Baritehas been used to weight this mixture. However, this mineral too rapidlyincreased an already excessive viscosity and it was thought that galena mightbe better for weighting such drilling fluid. The operator was anxious to trythe latter, but none was available in the district.

T.P. 918
Mud Technique in Iran
Authors: Strong M.W.
Published: June 2014

The technique of handling drilling muds varies somewhat, partly because of personal factors but mainly because of differences in formation, the type ofproblems, and the general drilling conditions in different localities.

The much greater depths to which bore holes are now carried have made necessarycloser attention to and great modifications of all aspects of drilling-mudtechnique. Increased depth means smaller hole, smaller drill pipe, smallerclearances, higher pumping pressures, higher differential pressures betweenshows and the mud column, less accurate control of the weight of the mudcolumn, delayed receipt of formation data, and poorer samples. It means longerdelays and greater hazards in rectifying mistakes or dealing with accidentaloccurrences. Equipment on a larger scale is necessary and more pains must betaken with layout. Lastly, the budget costs of raw materials have risen to highfigures and economy of time and of direct monetary expenditure have come tomean much more than formerly.

A mud laboratory is now part of the essential establishment of a modern oilfield and to it current problems can be submitted for the most thoroughinvestigation. The detailed chemical properties of all materials purchased orquarried have to be investigated. Detailed data on the physical properties haveto be ascertained and research on improvement of material and its mostefficient use has to be carried out.

In this paper will be discussed the main mud problems of Iran, some of whichare peculiar to local conditions while others are of the general type common toall workers in this subject.

T.P. 1005
Seismograph Prospecting for Oil
Authors: English Walter A. , Tracy Willard H. , Nomann Arthur , Ittner Frank , Kelly P.C.
Published: June 2014

Introduction

The four papers making up this symposium have been prepared especially forthose who have no knowledge of seismograph prospecting. To many peoplemathematics is a formidable subject, and many are discouraged from studyingseismograph prospecting under the mistaken assumption that the mathematicalrequirements are severe. In the papers presented here there is not a singlemathematical equation. We believe that considerable competence in dealing withsome of the most important problems of this work can be attained without anymathematical training whatever. At the present time, there is a real need forinterpretation of results by persons thoroughly competent to bring geologicexperience and imagination to bear on data that are subject to multipleinterpretation from a strictly physical viewpoint.

Likewise, those charged with the responsibility of planning seismographexploration campaigns would do well to become familiar with as much as possibleof the technical aspects of the work. They would then be in better position tojudge of its success in individual cases. It has often been said that theseismograph is a new structure-finding tool for the geologists to use. Using atool and using its product are two different things. One does not use anautomatic screw-threading machine when he buys a box of screws at the hardwarestore.

T.P. 1059
Decline-curve Analysis
Authors: Gross Henry Emmett
Published: June 2014

Two types of decline curves are considered and their applications arediscussed. The first is the well-known semilogarithmic decline curve having therate of production plotted on the logarithmic scale and the time on thehorizontal scale. The other curve is the percentage of oil in the fluid versuscumulative production, and it is plotted on Cartesian coordinate paper. Thesecurves are illustrated by carefully and adequately labeled graphs. Whereconditions permit application of both types of curves for rationallydetermining the reserves of a well, both should be applied and the mostconservative reserve should be chosen. Formulas are given for determining theeconomic limits. The semilogarithmic decline curve is treated first.
Significance of the Critical Phenomena in Oil and Gas Production
Authors: Katz D.L. , Singleterry C.C.
Published: June 2014

The critical phenomena have been studied during the past century but ourknowledge of the critical temperatures and pressures of complex hydrocarbonmixtures still is very limited. The critical temperatures and pressures of puresubstances have been examined in large numbers, and in great detail. Noexperimental determinations of the critical phenomena have been reported onsuch complex hydrocarbon systems as a reservoir fluid.

The critical temperature is defined by Taylor as follows: "there is sometemperature for each gas above which the gas cannot be liquefied. Thistemperature is called the critical temperature." The critical pressure of apure substance is the vapor pressure at the critical temperature. It should benoted that these definitions refer to a given substance in the pure state anddo not mean that the pure substance cannot be liquefied in the presence of asecond constituent.

The normal procedure for obtaining the critical temperature of a substance isto heat it in a glass tube 1.20 under pressure until the meniscus between theliquid and vapor phase disappears, although other methods, especially formixtures, have been used. However, when considering oil and gas reservoirs, itis more enlightening to. consider a critical phenomenon that occurs when amixture of oil and gas are compressed at a reservoir temperature until themeniscus disappears because the two phases become equal in composition. Thisconception, along with erroneous applications of the definition of the criticalphenomena of a pure substance to that pure substance when it is part of acomplex mixture, has caused confusion even among persons familiar with theclassical theories.

T.P. 971
Flow of Oil-water Mixtures through Unconsolidated Sands
Authors: Leverett M.C.
Published: June 2014

The behavior of mixtures of immiscible liquids in porous solids is ofrapidly increasing interest to those engaged in the production of petroleum. The operation of artificial water-floods and the control of natural onesimmediately raise questions concerning the fundamental nature of suchprocesses. Moreover, it is now recognized that often water occurs dispersed throughout the rock from which the oil issues into the well, 1 and thus tendsto move toward the well simultaneously with the oil. The work reported here isa laboratory investigation of the simultaneous, steady-state flow of oil andwater through the same column of unconsolidated sand. It is thus directlyrelated to the situation in which water occurs in oil-producing sands j it mayhave less direct implications for the displacement of oil from sands by water.However, it is to be clearly understood that the experiments to be describedwere performed primarily to obtain information of a more or less fundamentalnature, and are not an attempt to reproduce, on laboratory scale, any part ofan oil field.

The dynamic behavior of a system in which oil and water are flowingsimultaneously through sand is best described in terms of its "effectivepermeability" to either phase. For incompressible fluids flowing through asystem of uniform cross section, the effective permeabilities to the twophases, in darcys, may be defined by the equations.

In order to put the results obtained on a comparable basis for different sands, the effective permeabilities will be stated as fractions of the normalpermeability of the sand; i.e., fractions of its permeability to a homogeneousfluid.

T.P. 1003
Flow of Gas-liquid Mixtures through Consolidated Sand
Authors: Botset Holbrook G.
Published: June 2014

Experiments performed in this laboratory on the flow of gas-liquid mixturesthrough unconsolidated sands have been described and discussed in an earlierpaper. In these earlier experiments a definite relationship was found betweenthe liquid saturation of a sand and its permeability to the liquid or gasphase. Furthermore, the nature of the sand, the permeabilities of the sandsover a range between 17 and 260 darcies, appeared to have a negligible effectupon the saturation-permeability relation. Likewise experiments indicated thatthe viscosity of the liquid, or the substitution of an immiscible liquid forthe gas phase, had only a very slight effect on the permeability-saturationrelation. This conclusion has since been definitely confirmed by theexperiments of M. C. Leverett on the flow of oil and water throughunconsolidated sands. The sands used by Leverett were of very low permeability(between 6.8 and 1.04 darcies), while the oil-water viscosity ratio variedbetween 90 and 0.057.

Since the sands that constitute petroleum reservoirs are largely consolidated, although of widely varying degrees of consolidation, it was desirable to extendthe experiments on gas-liquid mixtures to consolidated sand. In the study ofconsolidated sands additional variables are involved, but for the initialexperiments the only new variable to be introduced was the cementingmaterial.

Experimental Procedure

A comparatively limited assortment of sandstones was available for theselection of the experimental material. Of these, the Nichols buff sandstoneappeared to be most suitable. It gives no visual evidence of any beddingplanes, it has a firm structure, permitting easy handling, and its permeabilityis about 0.5 darcy. Its only disadvantage is the fact that It contains anappreciable amount of ferric oxide which, for experiments involving water, willhydrate and reduce the permeability.

T.P. 1111
Effect of Temperature on Plastering Properties and Viscosity of Rotary Drilling Muds
Authors: Byck H.T.
Published: June 2014

The plastering properties of six representative California drilling mudswere studied over a temperature range of 700 to 1750 F. at several mud weights, using a high-pressure circulating filter press with full size consolidatedcores. In all tests, with untreated as well as with chemically treated muds, the filtration rates at elevated temperature were higher than at lowtemperatures and in nearly every case this increased filtration rate wasnotably larger than could be attributed alone to the decreased viscosity ofwater-the flowing medium-at elevated temperatures.

It is concluded that no existing method will permit even an approximatedetermination of the filtration rate at high temperature from data at roomtemperature. It is necessary to measure filtration at the temperature actuallyanticipated in the well, or to make a sufficient number of tests at variouslower temperatures so that a small extrapolation of these data to theanticipated well temperature may be applied. Such tests should be carried outon the mud as actually used in the well.

The viscosity of each of the muds was determined over the same temperaturerange. While no relationship was observed between mud viscosity and plasteringproperties, it was found that chemical treatment of the muds for viscosityreduction shifted the temperature of minimum viscosity to appreciably highervalues than for untreated muds.

Importance of Plastering Properties

A survey of the literature on rotary drilling muds clearly shows the growingrealization of theDDDD importance of plastering properties, not only from thepoint of view of the successful completion of the mechanical operation ofdrilling the well but also from the point of view of minimum impairment of thenatural flow possibilities of a given well.

T.P. 1116
A New Method of Constructing Subsurface Models
Authors: Bravinder Kenneth M. , Sheldon Dean H. , Koogle Jonathan E.
Published: June 2014

The solution of subsurface geological problems requires an analysis ofvertical and horizontal dimensional relationships. For many, the ability tovisualize structures in three dimensions is not easily acquired, and for areaswhere the structural conditions are complicated by faulting the need arises forillustrative models. This has led to the many forms of peg models, in which theusual course of construction includes a peg for the well bore, and thesuspension of strings from peg to peg to illustrate the formation correlationbetween wells, thus developing the usual folds and flexures. Such models provedunsatisfactory for the analysis of fault problems. Consideration was then givento the use of transparent materials.

A model of the Dominguez oil field was constructed in 1935, which consisted ofa series of glass panels from well to well on which the formations were shownin color. This model, though serving its purpose at the time, proved to beimpractical from the standpoints of cost, breakage hazard, and extremedifficulty in maintenance. The cost of materials was estimated to beapproximately $300, and the construction required the services of one man for aperiod of from 10 to 12 months. Maintenance after actual construction was anadditional expense.Consideration was then given to the use of celluloid, andafter some experimental work it was found that the advantages in its use were:a short construction time,ease of handling the material,sectionsare easily reworked,low cost.

Construction

It would be of little value to recount here the difficulties encountered in thebuilding of the first celluloid model. The conclusions drawn, however, suggestthe following procedure for those who contemplate the construction of such amodel:Determination of the Scale.-Accurate geological interpretation requires theuse of the same scale horizontally and vertically. It should be emphasized thatthe limited size of the celluloid sheets (20 by 48 in. maximum dimensions), thearea to be studied, the maximum depths to be plotted, and area of possiblefuture development are the controlling factors in adopting a scale to beused.Construction of the Base.-A satisfactory base may be constructed by usingtwo pieces of three-ply wood separated by strips of I by 2-in. material. Thistype of construction prevents warping of the base. The size of the base isdetermined by the dimensions of the area to be studied plus 5 in. on all sides.A map of the same scale as that adopted for the model, indicating the lines ofsection to be used, should be fastened to the base.

T.P. 1271
Slim-hole Drilling on the Gulf Coast
Authors: Alcorn I.W.
Published: June 2014

The cost of drilling in the past few years of proration and ever decreasingallowables has received increasing thought and study. It seems to parallel thestrides made with respect to pumping problems in 1932 and 1933. Low profitmargins stimulate the search for economies.

Any discussion of slim-hole drilling involves a multitude of abstract values, and the problem can be attacked only by a study of records and rationalthinking. In a measure, traditional methods must be studied with a questioningattitude.

The words "slim hole" may be somewhat misleading, as the term isentirely relative. For that reason I wish to define it as used in thisdiscussion. On the Gulf Coast, I would define a normal hole as one in which 103/4-in. surface casing has been set and below which a 9 7/8-in. hole is dug.With this as a datum, holes of larger diameter below surface would be called"large holes," with 12 1/4 in. as the "extra large" class andholes of smaller diameter classed in the slim-hole range, 6 1/4-in.representing about the minimum size. The optimum size has not been definitelydetermined, but the preference is for a program that would call for setting 85/8-in. surface casing and digging a 7 3/4-in. hole. Different sections of thecountry might very properly deviate from this practice because of differencesin depth, formations, regulations, or other factors.

This paper will be confined to a discussion of the drilling of exploratorywells, as the drilling of this class of wells is quite a different problem fromthat of drilling a proven field, although many of the same considerations applyin both cases, as will be apparent.

Although for many years shallow slim-hole and core-test holes of small diameterhad been dug, it was not, I believe, until the fall of 1937 that seriousconsideration was given to its application in drilling wells 7000 ft., 8000 ft.and 9000 ft. deep on the Gulf Coast. This does not mean that nearly all suchwells drilled on the Gulf Coast now are of the slim-hole variety, but only thatefforts have been aimed in that direction with very encouraging results andthere has been a very definite trend to reduce the size of holes, a trend thatprobably will continue.

As to exploration policy, there appear to be two distinct and opposite views.The one usually followed in the past was more or less designed to "shootthe works" on one well. Generally on the Gulf Coast, the depth at whichproduction might be obtained is limited by the drilling equipment andeconomics. With this thought in mind, wildcat wells are often planned with theidea of carrying the depth to 10,000 ft., or even 15,000 ft. All of thepossible hazards are anticipated and the general drilling and casing programsare so predicated. Such wells contemplate the drilling of large-diameter holes;the setting of at least one protective string of casing and an extensive coringpolicy, all of which finally adds up to an expensive well.

T.P. 1305
Scope and Content of the Petroleum Engineering Curriculum
Authors: Uren Lester C.
Published: June 2014

This paper reviews the industrial trends and changes in educational conceptsthat have led to the development of the modern petroleum engineeringcurriculum. A trend toward emphasis on engineering fundamentals is noted. Whilemost universities are committed to the traditional four-year engineeringprogram, it is agreed that more than four years is necessary for academicpreparation of the petroleum engineer in all phases of his profession. Theauthor proposes a coordinated program of undergraduate and graduate trainingthat will permit of adherence to the general pattern of the present four-yearengineering course, with provision for extension of the program intospecialized graduate courses of professional character. In the latter, emphasismay vary with the interests and objectives of the individual student. Aspecific undergraduate curriculum is proposed in which upward of 80 per cent ofthe available time is devoted to engineering fundamentals. A broad survey ofthe professional field is afforded in courses grouped in the third and fourthundergraduate years, but detailed treatment of the professional aspects ofpetroleum engineering is reserved for the graduate program.

Introduction

Of necessity, engineering curricula must ever be changing to reflect the newtechniques, the changing concepts that are presented as the engineeringindustries develop and unfold. Particularly is this true of the youngerengineering curricula representing comparatively new and rapidly changingindustries such as the petroleum industry. Institutions that planned theirpetroleum engineering curricula a decade or two ago now find that the petroleumindustry has become vastly more technical in its requirements. Entirely newmethods and techniques have come into vogue and must be given place in thecurriculum, and some of these are of a character that demands changing emphasisin the fundamental preparatory subjects. College and university facultiescannot complacently assume that curricula in this field that were consideredappropriate 10 or 20 years ago still reflect the needs of the industry thatthey are designed to serve. If they do, their graduates will be poorly equippedto meet the requirements imposed upon them by a rapidly changing industry.Perhaps it is not too much to expect academic authorities to anticipate thetrends of industry and equip their graduates with what they will need to attainleadership 10 or 20 years after graduation. Whether or not this desirableobjective is possible, there is no excuse for allowing curricula to fall behindthe current needs of industry.

T.P. 1350
A Comparison of Marsh-funnel and Stormer Viscosities of Drilling Muds
Authors: Owen J.E.
Published: June 2014

Experiments on twenty-six drilling muds were carried out in an effort toestablish a correlation between the apparent viscosity values for these muds asobtained with the Marsh funnel and the Stormer viscometer. This required acalibration of both instruments in which the density of the calibrating liquidswas taken into account. Corresponding to the Marsh-funnel viscosity values thatwere obtained at 1500 c.c. in, 1 qt. out, equivalent Stormer viscosity valueswere obtained at a Stormer cylinder test speed of approximately 1100 r.p.m.Further, a linear relation between the logarithms of the Stormer cylinder testspeed and the resulting apparent viscosity was found to exist for the mudstested for 200 to 1000 r.p.m. The significance of the slope of this linearrelationship is discussed as it applies to the field use of drilling muds. Itwas concluded that Marsh-funnel viscosity measurements are expressible inabsolute units that may be correlated with Stormer viscosity measurements, provided these are made in the manner described in the paper.

Introduction

The Marsh funnel is used almost universally to determine the viscosity ofdrilling muds in the field. The Stormer viscometer is commonly used todetermine the viscosity of drilling muds in the laboratory. With the Marshfunnel, the time required for one quart of mud to flow out of the funneloriginally filled with 1500 c.c. is often taken as the measurement ofviscosity. With the Stormer instrument, drilling mud is tested at a cylinderspeed of 600 r.p.m. and by means of calibration data the apparent viscosity isexpressed in absolute units. Neither of these instruments is an absoluteviscometer, and apparent viscosities obtained with either are influenced by thearbitrarily standardized conditions under which the measurements are made.

It is disconcerting to the man in the field to be told that laboratorymeasurements of the viscosities of a group of muds differ widely, when he hasalready observed that they have identical viscosities when tested in the Marshfunnel. Drilling muds are not perfect fluids, therefore it is not surprising tofind a lack of correlation between the apparent viscosity of a mud asdetermined with the Marsh funnel and that determined with the Stormerviscometer.

The work described here was undertaken to develop a correlation betweenMarsh-funnel and Stormer viscosity measurements. To a considerable degree thishas been accomplished. This study has resulted not only in a betterunderstanding of the two viscosity instruments and the data obtainable fromthem, but has given considerable information regarding the viscositycharacteristics of drilling muds.

T.P. 1373
Steady Flow of Gas-oil-water Mixtures through Unconsolidated Sands
Authors: Leverett M.C. , Lewis W.B.
Published: June 2014

The dynamic behavior of a multiple fluid system is completely describable interms of driving forces and resistances to flow. The latter are proportional tothe viscosity of the fluid under consideration and inversely proportional to aproperty of the system termed the" effective permeability" to thatfluid, a property therefore defined by this relation.

Since three phases are usually present in oil reservoirs, it is essential toknow the effective permeabilities to the several fluid phases, and therelationship between the composition of the fluid in the pore space and that ofthe flowing stream, in order to handle satisfactorily certain problems of oilproduction. In this regard, there are many unknown factors and parameters, andmany that can be evaluated only indirectly. However, it is expected that workalong lines similar to this present undertaking will help materially in solvingthese problems.

Previous workers in this field have investigated the two-phase systems, water-gas, water-oil in unconsolidated sands, and water-gas in consolidatedsands. The extension of the study of the flow of heterogeneous fluid systemsfrom two to three phases involved only slight changes in technique. Theapparatus used in the present work, except for slight changes to be described, was that used by Leverett in his water-oil experiments. Correlation andinterpretation of data were made by methods analogous to those used in two-phase work. The relative permeability to a phase-the effective permeabilitydivided by the permeability of the system to a homogeneous fluid-was employedthroughout in correlating the rate of flow of that phase with the compositionof the pore space.

Quantitative measurements of two independent physical properties of the systemwere required to determine the composition of the pore space. As in thetwo-phase work, the fraction of water was determined electrically. The gasfraction was determined by measuring changes in volume accompanying measuredpressure changes. Suitable account was taken of the solubility of the gas inthe liquid phases, and of the vapor pressure of the water phase. Since thiswork was exploratory in nature, no attempt was made to obtain highly accuratenumerical results. Reasonable precision and reproducibility were sought.

Experimental Procedure

Variables Considered.-Of the properties of the fluids, the oil viscosity ismost likely in practice to vary widely. Variations in oil viscosity weretherefore included in this work, but variations in other properties of thefluids are as yet unexplored. It appears unlikely that the normally encounteredvariations will produce significant changes. The observations were made atfairly high pressure gradients, no attempt being made to detect a variation ofthe relative permeabilities with pressure gradient.

T.P. 1206