bluuebunny/crossref_metadata_2025_split huggingface dataset:
Response of a Gulf Coast Drilling Mud to Chemicals, Temperature and Heat-treatment
Authors: Fancher George , Whiting Robert L. 
Published: June 2014

Abstract
A typical drilling mud from the Hastings oil field, Brazoria County, Texas, containing only 8 per cent (dry basis) of material of colloidal dimensions, which is largely illite, was concentrated to a density of 10.2 lb. per gal. andused in this study. The effects of water dilution, treatment with complexpolyphosphates, temperature and the time of heating upon the rheologicalproperties of the mud were investigated. It was found that water plays animportant part in chemical treatment and that sodium acid pyrophosphate andsodium tripolyphosphate were more efficient than other complex polyphosphatesfor chemical treatment. Muds treated with either of these chemicals manifestedmaximum reduction in viscosity and minimum filtration rates at lowconcentrations. Furthermore, mud treated to minimum viscosity with either ofthese two chemicals was virtually unaffected by heat-treatment.

Introduction
The drilling of deep wells is dependent upon the use of drilling mud, andproblems frequently arise concerning the effects on mud of temperature, prolonged heating and aging. The use of chemicals to control the rheologicalproperties of mud is a well-established practice. Salts of weak organic acidssuch as sodium tannate or gallate were used at first until the complexphosphates of sodium were found to be more efficient. Consequently, it seemed important to investigate the reactionof a mud to chemical treatment with phosphates, temperature, heat-treatment andaging, particularly since previous work in the laboratory at the University ofTexas had provided the particle-size distribution and mineral composition of Hastings mud.

Properties of Mud Used in Experiments
A large sample of the mud from a drilling well in the Hastings field, Brazoria County, Texas, was obtained directly from the circulatory system. Someof the general physical characteristics of the mud and other data are presentedin Table I. The Alexander mud was used for the experimental work. Comparisonwith Curkeet mud indicates a considerably greater dilution but otherwisesuggests similarity. The mineral composition and particle-size distribution ofCurkeet mud (Table 2) are available (Fancher and Oliphant). It is suggestedthat Alexander mud would have a similar composition.
T.P. 1589
Effects of Certain Gums and Starches on Filtration of Salt-water Muds at Elevated Temperatures
Authors: Perkins Frank , Craft Benjamin C. 
Published: June 2014

Abstract
The wall-building properties of salt-water muds can be maintained at hightemperatures by additions of gum karaya, gum ghatti, gelatinized starch, orcommercially prepared starch. A germicide should be used to preventfermentation.

Introduction
The behavior of drilling mud has received special attention from thepetroleum industry within the past few years in numerous research projectsdealing with such subjects as chemical treatment, gelation, and filtrationcharacteristics.
The importance and control of filtration, or water loss, is readilyapparent. It affects the analysis of side-wall cores and interpretation ofelectric logs; it controls to a large extent the work of primary cementing, reduces the amount of expensive fishing, and permits the running of longstrings of casing.
It has been found that among the many factors that have an adverse effect onfiltration, the presence of electrolytes, in general, and of salt, inparticular, is outstanding. The effect is one of flocculation of the colloidsdue to neutralization of the negative charges on the clay particles. Thisreaction is further increased on the Gulf Coast because high temperaturesreduce dispersion to a minimum, causing increased flocculation in both fresh-water and saltwater muds. The problem of reducingwater loss in salt-water muds by the addition of gums and starch at atmospherictemperature has been investigated, and many successful field tests in WestTexas indicate its solution. From the work of Byck it is concluded that noexisting method will permit an approximate determination of the filtration rateat high temperatures from data taken at room temperatures. Filtration should bemeasured at the temperature actually anticipated in the well, or at least at anumber of lower temperatures and extrapolated over a small range.
A laboratory study has been made of the chemicals available for thefiltration characteristics of salt-water muds at high temperatures, and the useof germicides to prevent fermentation.
T.P. 1551
A Method for Evaluating Pressure Maintenance
Authors: van Wingen N. 
Published: June 2014

Abstract
This report describes one possible method of determining the economics ofpressure control and maintenance operations as applied to a deep, high-pressurereservoir having a low gas-oil ratio. The results of the analysis indicate thata premise of increased recovery need not be predicated to justify economicallysuch methods of operation. The entire problem of determining the feasibility ofpressure-maintenance operations is thus resolved into a consideration of thefollowing:a determination of increased recoveries, resulting from pressurecontrol and maintenance as against deferred sales for the gas, including aconsideration of the economic feasibility of purchasing gas for injectionpurposes;an investigation of the extent to which it will be possible tocontrol the expansion of the secondary gas cap so that no appreciableby-passing of the cycled gas will result.

Introduction
One of the most important factors involved in the selection of a method orscheme of operation for any given reservoir is the consideration of optimumeconomic returns. As wasteful operation leads to diminished profits, a greatdeal of thought has been given in the petroleum-producing industry toimprovements in the technique of developing and producing oil fields. Only inthe last decade, however, has sufficient knowledge become available for theseconsiderations to be extended effectively from the early standpoint whenimprovements of mechanical equipment were of chief concern to include theconcept of the effect of exploitation methods on the ultimate recoveryobtainable from a particular reservoir.
In this paper a description is given of one possible method of determining theeconomics of a primary recovery, or pressure-maintenance operation, as appliedto a deep, high-pressure, low-permeability reservoir. The analysis has beenmade in two parts on the following basis:That progressively higher degrees of pressure-maintenance operations willresult in correspondingly greater ultimate recoveries, which the writerbelieves actually will be true.That the oil and gas recovery will be the same as would be obtainable by thenatural depletion method of operation regardless of the degree of pressuremaintenance.
The primary intent is thus to attempt to demonstrate to what extent aconsideration of relative increased recoveries for operations under variousdegrees of pressure maintenance need be predicated in order to justifyeconomically pressure-maintenance operations.
T.P. 1665
Positive Colloid Muds for Drilling through Heaving Shale
Authors: Bond Donald C. 
Published: June 2014

Abstract
Positive colloid mixtures have been prepared which possess all of theproperties desirable in a drilling mud for penetrating heaving shale. Thesepositive colloid muds are stable and they can be weighted to almost any desiredspecific gravity. They can be given any viscosity or thixotropic gel strengthrequired, within reasonable limits. They have excellent filtration, orwall-sealing, properties. They are not affected by relatively hightemperatures. They cost, initially, a little more than silicate muds, but theyhave many advantages over silicate muds. They have electrical resistivitiesapproximately equal to the resistivity of shale, which is highly desirable whenthe hole is to be logged electrically. Best of all, these positive colloid mudsare true colloidal mixtures, which have no swelling or disintegrating effect onheaving shale. '
The Nature of Heaving Shale
The penetration of heaving shale formations during drilling may be inferredfrom several effects that can be noted at the surface. The mud pumps may slowdown or the circulation of mud may cease entirely. The physical properties ofthe drilling mud, such as specific gravity, viscosity, or gel strength, maychange rapidly. (These effects are not to be confused with those caused bymixing of the mud with brine or with cement.) Cavings of shale may appear inthe mud returns. Finally, the drill pipe may be seized so firmly that it cannotbe turned.
It is found that these effects are symptoms of two conditions that may exist inthe hole. In some instances, a large cavity filled with sticky, viscous shaleis formed at the bottom of the hole when the heaving shale is penetrated by thedrill. In other cases a plastic mass of swollen shale sloughs into the drillhole at some point above the drill. In either case the result is a decrease orcomplete cessation of circulation of mud, accompanied by increased resistanceto the rotation of the drill pipe.
T.P. 1674
Effect of Certain Micro-organisms on the Injection of Water into Sand
Authors: Plummer F.B. , Merkt E.E. , Power H.H. , Sawin H.J. , Tapp P. 
Published: June 2014

Abstract
This paper describes briefly some of the common micro-organisms that occurin waters obtained from tanks in the Luling and east Texas oil fields;discusses in some detail the effect of the organisms on the chemical content ofthe waters; describes the bioproducts and precipitates resulting from thegrowth of bacteria and algae; and illustrates by means of experiments theeffect of these organisms and their precipitates on the permeability of oilsands into which contaminated water is introduced. The experiments anddiscussion are designed with special reference to waterflooding andwater-disposal problems.
Early Work on Micro-Organisms in Oil-Field Waters
It has long been known that microorganisms are present in oil-field waters.Rogers, Bastin, Gahl and Anderson Ginsburg-Karagitscheva, Ginter, and Bushnelland Haas have pointed out their presence and possible chemical effects onoil-field waters. Sanders has found them in oil and Klinkenberg has mentionedthe possible effect of bacteria on the flow of water through sand. However, very little has been published by petroleum engineers on the quantitativeeffect of micro-organisms on the permeability of oil-field fluids or on methodsof counteracting harmful chemical effects of oil-field bacteria or on methodsof sterilizing and purifying oil-field waters on a large scale. Mostpublications on the microorganisms of springs and ponds are by biologists andwritten from a biological point of view, and they do not deal particularly withoil-field waters.

Description of Micro-Organisms
Four types of organisms are present in oil-field waters and appear to play aprincipal part in producing harmful precipitates; that is, iron bacteria, sulphur-oxidizing bacteria, sulphate-reducing bacteria, and blue-greenalgae.
The iron bacteria were discovered by Ehrenberg in 1836. Many kinds occur.One of the commonest forms in Texas waters is Gallionella. This form is longand ribbonlike or tapelike, and under the microscope it looks like evenlytwisted, tiny, spiral threads or bands (Fig. I). The spiral bands may occur assingle filaments or may be twisted together. The filaments are covered withferric hydroxide secreted by the bacterial cell (Fig. 2). The terminal cellstructure, only 1.2 by 0.5 microns in size, consists of two coccuslike cells,0.3 by 0.5 microns in size.
T.P. 1678
Natural Potentials in Sedimentary Rocks
Authors: Dickey Parke A. 
Published: June 2014

Abstract
Potential differences between strata of shale and sandstone have beenrecognized for about 15 years, and they form the basis of the electricallogging of oil wells. Hitherto these potentials have been ascribed solely toelectrochemical reactions caused by the disturbing effects of the water in thedrill hole through which they are generally measured. Observations by theauthor in wells empty of water and in a mine shaft suggest that potentialdifferences between sandstones and shales are natural and specific propertiesof the rocks, although they are modified in measurement by the disturbingeffects of the water in the drill hole. The cause of these potentials probablyis to be sought in the relative polar adsorptive capacities of quartz and clayparticles.

Introduction
The existence of potential differences in the surface of the earth has beenknown for some time, and their measurement has facilitated the discovery ofgeological discontinuities such as ore bodies. The technique of measurement hasbeen well established. 1–3
In measurements in oil wells, it has been found that the potential of shaleswith respect to some arbitrary reference is very nearly constant in anyonewell, at least below the zone to which meteoric water has gained access.Sandstones and some other types of sedimentary rocks have a difference ofpotential with respect to shale that is negative and may attain a value of 200millivolts or more. The difference of potential, as usually measuredcommercially with water in the hole, is distributed over about one footvertically at the top and bottom contacts of the sandstones. The sharpness ofthe curve at the formation contacts can be improved by using a short electrodethat is close to the wall of the hole.
These potentials generally have been ascribed to the disturbing effects of thewater in the drill hole. Potentials have been found, however, in wells in whichno water was present. In the course of experiments in electrical logging inPennsylvania, carried out by the Pennsylvania Geological Survey, observationswere made of several phenomena that hitherto have not been described, to theauthor's knowledge, in the published literature.
The potential differences across the contacts of sandstone and shale are calledin this paper "natural potentials," as distinguished from thepotentials caused by electroendosmosis (electrofiltration) and concentrationdifferences, which will be discussed subsequently.

Potentials in Cored Well
In the spring of 1942, the author measured the potentials in an exploratorywell (Day 13, near Grand Valley, Pa.) which had been cored with diamond tools.The potentials were first measured with fresh water in the hole. A null balancepotentiometer was used in this and all the other measurements described in thispaper.
T.P. 1625
The Interpretation of Earth-resistivity Measurements
Authors: Muskat Morris 
Published: June 2014

Abstract
The method of R.W. Moore for determining subsurface interfacial depths bymeans of integrated curves of apparent resistivity has been analyzedtheoretically. It is found that the only unique tangents that can be drawn tosuch curves are the asymptotes at infinite electrode spacing and the tangentsthrough the origin at vanishing electrode spacing. Explicit expressions havebeen derived for the relationship between the electrode spacing at the pointsof intersection of these tangents and the thickness of the surface strata as afunction of the conductivity parameters for the two-layer and three-layerearths. It is found that in all cases the electrode spacing at the points ofintersection will exceed 3/2 of the thickness of the surface layer, and mayeven become indefinitely large as the resistivity of the deepest layersincreases as compared with that of the surface layer. These results do notagree with the empirical findings of Moore that the intersection of the tangentlines fall at an electrode spacing very approximately equal to the thickness ofthe surface layer.

Introduction
In a recent paper, R.W. Moore proposed a new method for the analysis andinterpretation of earth-resistivity measurements. This consists essentially inplotting against the electrode separation of a Gish-Rooney system the integralof the apparent resistivity with respect to the electrode spacing, andobserving the breaks in the integral curves. Specifically, tangents are drawnto the various segments of the integral curves, which show appreciablydifferent slopes, and the intersections of these tangents are used asindications of the depths of the various underlying strata. By numerousexamples Moore has shown that the electrode separation at the firstintersection so found agrees very closely with the depth of the bottom of thesurface layer. Moreover, in a number of instances the intersections for greaterelectrode spacings seemed to correspond to the depths of deeper beds.
T.P. 1761
Viscosity of Natural Gases
Authors: Bicher Leo B. , Katz Donald L. 
Published: June 2014

Abstract
A correlation is presented for predicting the viscosities of light paraffinhydrocarbon mixtures such as natural gases for temperatures from 0? to 400?F. and forpressures from atmospheric to? 10,000 lb. per sq. in. The correlation is based on theviscosity data for the methane-propane system and requires only a knowledge of the molecularweight of the natural gas. The viscosities of natural gases reported in the literature up to2500 lb. were reproduced by the correlation with an average deviation of 5.8 per cent.

Introduction
The viscosity of a natural gas is required whenever calculations are made ofthe pressure drop that occurs while the gas flows through pipes or porous media. Methods ofpredicting the viscosities of gases at the present operating pressures are not available.This paper presents a simple method of predicting the viscosity of a natural gas in thesingle-phase region from its molecular weight, temperature, and pressure.

Viscosity of Methane-Propane Mixtures
The viscosity of methane, propane, and four of their binary mixtures, 2?,4?,60, and 80 mol per cent, have been determined for pressures from 400 to 5000 lb. per sq. in.and temperatures from 77? to 437?F., with an experimental accuracy of 3.2 per cent.The apparatus used in the "investigation was a modification of that employed inprevious studies on the viscosity of normal paraffin hydrocarbons. It consists of a viscosimeterof the rolling-ball, inclined-tube type, with auxiliary equipment for making up andcharging binary mixtures into the viscosimeters. The viscosity data on the methane-propanemixtures have been plotted as a function of molecular weight with lines of constant pressure, charts of constant temperature in Figs. I to 3. These charts are extrapolated attemperatures below 77?F. and at pressures above 5000 lb. per sq. inch. Prediction of Viscosityfrom Molecular

Weight of a Natural Gas
At atmospheric pressure the viscosity of light hydrbcarbon gases increased withincreased temperature, contrary to the change of viscosity of liquids with temperature.The atmospheric viscosities of the normal paraffin hydrocarbons have beendetermined by several investigators and are plotted in Fig. 4 as a function of molecular weight, with extrapolation to 896?F. and to 220 molecular weight. Data for isopentane andnormal pentane show less than 2 per cent difference in viscosity, indicating that Fig. 4 canbe used for isomeric paraffin hydrocarbons with an accuracy of approximately 2 per cent.Trautz and Sorg determined the atmospheric viscosities of methane-propane mixtures and showedthat they are proportional to the molecular weight.
T.P. 1599
Applications of the Electric Pilot to Well Completions, Acidizing, and Production Problems in the Permian Basin
Authors: Lehnhard P.J. , Cecil C.J. 
Published: June 2014

Abstract
The paper describes the use of the Electric Pilot in the Permian Basin formaking permeability surveys of wells and for the selective acidization ofwells. A general summary of the information obtained from the many permeabilitysurveys run in this area is given, and the possible application of thisinformation to reservoir control problems is discussed. The application of theElectric Pilot on specific wells, involving well completion, acidizing andworkover operations is also included.

Introduction
The Electric Pilot is a comparatively new tool in oil-producing areas. From thebeginning, the possibilities of this new service caught the imagination of manyof the oil operators and acidizing engineers. Through the continued and everincreasing use of the pilot during the past year, and the close cooperation ofthe oil operators who have used this service, the efficiency and utility of theElectric Pilot service has been increased to a point where it is now a wellestablished and recognized service.
There are two major uses for the Electric Pilot:permeability survey;selective acid treatments.
Permeability surveys are made to determine the thickness of the variouspermeable sections at the borehole, the vertical position of these zones at thebore hole, and the relative capacities of the various zones.

Nomenclature
Data obtained from the permeability survey are used to calculate threedifferent indexes that pertain to the volume of fluid injected into the variouspermeable zones. A nomenclature for these various indexes has been set up, which correspond with the various productivity indexes, except that they are ameasure of injected fluid rather than produced fluid. The nomenclature anddefinition of the indexes used in connection with a permeability survey by theElectric Pilot are as follows:Capacity.-The volume of water injected into an individual permeable zone, ingallons per minute.Capacity Index.-The volume of water injected into an individual permeablezone, in gallons per minute per pound per square inch differentialpressure.Specific Capacity Index.-The volume of water injected into an individualpermeable zone in gallons per minute per pound per square inch differential perfoot of thickness of the zone at the borehole.
Capacity is the most generally used index, and for planning initial acidizingprocedures and most workover jobs it is sufficient.
T.P. 1759