bluuebunny/crossref_metadata_2025_split huggingface dataset:
Some Recent Developments in Mud-analysis Logging
Authors: Pixler B. Otto 
Published: June 2014

Abstract

Method
As the drilling of a well progresses, the drilling bit dislodges anddisintegrates a cylindrical section of the formation. If oil or gas iscontained in the pore spaces of the cylinder, some of the contents of theseporous spaces will be entrained in the drilling fluid. In wall logging by mudanalysis, the mud is continuously examined for oil and gas on its return to thesurface, and the results are correlated back to the actual depth of the hole atthe time the mud was clearing the eyes of the bit.
The test for gas is made by diverting a portion of the circulating mud from theflow line to a separator or gas trap, where the mud is thoroughly mixed withair and a portion of the gas entrained in the mud is removed. A stream of airis drawn countercurrent to the flow of mud in the gas trap, thus materiallyassisting the separation of the gas from the mud. The air-gas mixture is thendrawn into a "hot-wire" gas-detector instrument where the percentage ofthe combustible gas is determined.
The presence of oil in the formation drilled is detected by a physicalexamination of the drilling mud under ultraviolet light. A sample of the mud istreated to reduce the surface tension and gel strength, after which it isplaced in a viewing box.
Mud-analysis logging provides identification of the fluid content of formationsdrilled by the rotary method and permits the accurate correlation of oil andgas shows with the depth. Mud-analysis logging eliminates much coring and hasan especially important application in drilling programs when coring isparticularly hazardous or the electric log is difficult to interpret correctly.An appreciation of the factors that influence the results of the mud analysis, such as rate of penetration, mud properties, coring, and characteristics ofreservoir rock as related to the "flushing effect," permits a betterunderstanding of the mud-analysis log.
Recent studies of the relationship of the two gas readings obtained by thegas-detector instrument have proved significant. The difference between thetotal combustible gas reading and the higher molecular weight gas readingindicates the presence of methane. With few exceptions, zones not showing anincrease of methane probably can be condemned. Mud-analysis logging furnishesvaluable information, which generally cannot be obtained by othermethods.

Introduction
Logging by mud analysis of wells drilled with rotary tools is a direct methodof locating oil-and-gas-bearing formations. The use of this method of logginghas increased each year until now more than 20'Field units are being used in 13oil-producing states and in some foreign countries. Several papers have beenpublished in the petroleum trade journals describing in detail the equipmentand the application of mud-analysis logging. This paper will discuss brieflythe method and review its application and some of the late developments.
T.P. 2026
Geothermal Gradients in Mid-Continent and Gulf Coast Oil Fields
Authors: Nichols Earl A. 
Published: June 2014

The purpose of this paper is to present a contour map that shows thegeographical variation in geothermal gradients in the Mid-Continent and GulfCoast oil fields.

Introduction
Frequently there arises the need for an estimation of the temperature to beexpected at a predetermined depth in working with a wildcat or in deepening oldproduction into zones that are relatively unknown. The study of geothermalgradients in oil fields has been made previously by many investigators. One ofthe pioneers in this work was C. E. Van Orstrand, who, as well as most of theother investigators, was primarily interested in the relation betweentemperature and depth in a given locality. Between 1921 and 1929, AmericanPetroleum Institute Research Project No. 25 fostered a thorough study of earthtemperatures. R. W. French did some work in California, the results of whichwere published in 1939.3 In most of these studies, an attempt was made tocorrelate temperatures in a rather localized area. This paper will show theresults of an attempt to correlate temperature gradients over rather largeportions of the Mid-Continent and Gulf Coast area.

Method of Obtaining Data
It has been found that for complete thermal equilibrium to be established in awell, the well must stand undisturbed for a period of several hours to severalweeks, depending upon the way the well was produced prior to the shut-inperiod.
The data in this paper were obtained in conjunction with running pressures inwells or in taking samples of reservoir fluid. Glass maximum recordingthermometers were used in all but a few instances. The wells had been shut infrom one hour up to 10 or 12 days. Since the wells were normal producing wells, some of the shut-in times undoubtedly were insufficient for complete thermalequilibrium to have been established and the temperatures measured do notnecessarily represent the true earth temperatures. They do represent thetemperature conditions that will? be encountered in a well that is producingoil. The data, therefore, can be useful in working with or in estimating thetemperatures to be expected in producing reservoirs.
In obtaining a thermal gradient by dividing the difference in temperature ofthe formation and the mean annual surface temperature by the depth of theformation, one is assuming the depth-temperature line to be straight.Depth-temperature curves are almost straight lines. However, on closeexamination of accurate data, a slight curvature usually is observed. Mostwells yield curves with slopes increasing with increasing depth. These curvesare believed to be from wells that are in and are underlain by sedimentarymaterial. Some few curves have slopes that decrease with increasing depth.These curves are believed to be from wells that are underlain rather closely bygranite or some other igneous rock.
T.P. 2114
Some Experiments on the Mobility of Interstitial Waters
Authors: Russell R.G. , Morgan F. , Muskat M. 
Published: June 2014

Abstract
Core experiments with radioactive tracers are reported in which an artificialradioactive material, radiovanadium, was used in aqueous solution in a study ofthe mobility of connate water. Sandstone cores saturated with active water werefirst oil-flooded to simulate virgin sand conditions in which the pores arefilled with oil and connate water. They were then subjected to flooding withinactive water. Measurements were made of the activity of various portions ofthe effluent as well as the activity of the core after the flooding process wascompleted. In additional experiments the distribution of activity along thecore was measured during the flooding process. In still other experimentsdirect flooding tests were made on cores fully saturated with active water. Inall cases it was found that after injecting into the core a volume of inactivewater equal to a pore volume, the effluent contained more than 80 per cent ofthe active content originally in the core. It is felt that these results implya high degree of mobility of the connate water when subjected to flooding, although at least a partial contribution of the effect of tracer transferwithin the core cannot be definitely excluded. The implications of this resultwith respect to water-flooding, core analysis and electric logging arediscussed. A better approach to determining the connate water saturation ofoil-producing rocks, by measuring the fluid content of core samples at thesurface, is by the use of crude oil or oil-base muds as the coring fluid.

Introduction
Although water flooding is of considerable importance in the recovery of oil, comparatively little is known with certainty about the role played by theconnate water during the operations. Two possibilities exist. Either theconnate water is retained in the formation while the flood water sweeps past, or it is pushed along to a greater or lesser degree by the flood. Thus far noexplicit recognition in terms of quantitative studies appears to have beengiven to the displacement of connate waters by the intruding extraneous waters, although such a possibility might be important in determining the efficiency ofthe oil -displacement process in water-flooding operations, especially inargillaceous rocks. On the other hand, it is a common observation that thefirst water produced with the oil as a result of water-flooding is definitelysaline. Similar questions regarding the mobility of the interstitial waterarise in the quantitative description of the advance of edge-water drives.
T.P. 2054
Estimating Interstitial Water by the Capillary Pressure Method
Authors: Thornton O.F. , Marshall D.L. 
Published: June 2014

Abstract
Results of the determination of the interstitial water content of several coresamples from oil reservoirs are presented. Data obtained by the capillarypressure method, which has recently been developed, are compared with watersaturations measured in cores cut with oil-base mud and with values calculatedfrom the electrical resistivity of the formation. The agreement between thecapillary pressure and other methods, combined with the fact that similaragreement has been obtained by others, indicates that the capillary methodproperly applied yields results sufficiently accurate for most engineeringpurposes. In some cases, it may be possible to extend the utility of dataobtained with the capillary pressure method by correlation of interstitialwater saturation with more easily measured physical properties of themedia.

Introduction
Several methods are in use for determining or for estimating the interstitialwater saturation at given points within oil and gas reservoirs. The directmeasurement of the water content of cores obtained with nonaqueous fluid in thehole is believed to be an accurate method under most conditions. The water'saturation may be calculated by use of the resistivity curves of the electriclog, 1 although this method is not applicable under conditions that exist insome reservoirs. Recently, a method has been developed and described whereinthe interstitial water saturation of cores is measured at a capillary pressuresuch that conditions existing in the reservoir are simulated. The purpose ofthis paper is to present data obtained by use of this latter method, and tocompare the results obtained with determinations made by other means.

Method
The theory underlying the capillary pressure method applied to petroleumreservoirs has been discussed adequately in the literature by Garrison, Leverett, and others. Briefly, and simply, capillary pressure is defined as thedifference in pressure between two contacting fluid phases, such as oil andwater. For the simplified sand, water and oil system illustrated in Fig I, thepressure difference can be stated as follows where p. is the capillary pressurein pounds per square inch, Y is the interfacial tension between oil and waterin pounds per inch, 7, and 72 are the radii of curvature of the interfacebetween oil and water in inches.
Capillary pressure varies in a given reservoir with depth because of thegreater density of the water phase as compared with oil or gas.
T.P. 2126
Plastic Used to Consolidate Incompetent Formations
Authors: Cardwell P.H. 
Published: June 2014

Abstract
The effect of various plastics upon the permeability of a sand and themechanism of their ensuring permeability within the consolidated sand body isdiscussed, Data are presented on various properties of the plastic materialsused in sand consolidation and the effect of temperature and usable temperatureranges are considered.
The recovery of petroleum from unconsolidated sands presents serious productionproblems, owing to sloughing of the formation. The solution of some of theseproblems usually has been by mechanical methods. The ideal way of controllingthe sloughing tendencies of these unconsolidated formations, however, is toprevent the movement of the individual sand grains by the use of a bondingmedium.
A step in the desired direction was taken by Irons and Stoesser when theytaught the use of liquid plastics to produce a consolidating deposit thatprevents sloughing. More recently, Wrightsman and Buckley proposed amodification of this process. In this use of the liquid plastic, the sandgrains become coated and the ensuing hardening of the plastic by polymerizationor condensation cements together the sand particles. Liquid plastics that havebeen suggested for this purpose are of the following types: phenolformaldehyde, alkyd resins, vinyl type resins, polystyrene and the acrylic esters.
When the flow of fluids through a sand must not be materially reduced, it isessential only to cement together the sand grains with liquid plastic and leavea portion of the interstitial space for fluid flow. To be assured of obtainingfluid flow through the sand interstices after injection of plastic, it has beennecessary in the past to remove the excess plastic from the interstices betweenthe particles before it sets.
Wrightsman and Buckley suggest two methods for the removal of the excessplastic from the interstices of the sand:to flush the excess plastic backinto the formation, away from the well bore, by use of oil or water;toproduce the well before the plastic has set, thereby moving the excess plasticinto the, well bore.
Under certain well conditions it is very difficult toremove the excess plastic from all parts of the formation by either of thesemethods and leave the formation consolidated with no sections completelysealed.
The method described herein of retaining permeability within a sand body is touse a liquid plastic that upon setting ensures permeability within theconsolidated sand body, This cements the sand grains but obviates the need forremoving plastic from the interstices of the sand. One of the ways ofaccomplishing this is to use a liquid plastic that occupies a considerablygreater volume than the solidified resin it yields on further polymerization orcondensation in situ. In order to be satisfactory, the volume of the plasticwhile liquid should be at least one and one half times the volume of the solidformed.
T.P. 2148
Advantages of Brines in Secondary Recovery of Petroleum by Water-flooding
Authors: Hughes Richard V. , Pfister Rudolf J. 
Published: June 2014

Abstract
The necessity for getting more water into sands of low permeability in anysecondaryrecovery water-flood operation in order to recover all the availableoil always has been a major problem. In the early days of waterflooding theaddition of soda ash and caustic soda to fresh input waters was recommended andtried without success in the Bradford field. The most frequent difficulty wassand plugging. The use of natural and artificial brines often has beensuggested for water-flooding, in the belief that laboratory observations ofdecreasing fresh-water throughput rates in measuring water permeabilities ofconsolidated sand cores might be partially explained by swelling ofclays.
A review of available literature bearing on the subject and related laboratoryexperiments are presented herein, offering an explanation for failure in use ofsoda ash, and caustic soda waters and supporting the recent concept that everywater used for input purposes in the secondary recovery of oil should possesssuch physical and chemical characteristics as to keep the clay content of theproducing sands in a permanently flocculated condition. Produced brines meetthis requirement. Their use is recommended as a means of increasing intakerates of tight sands and oil recoveries, as a solution to brine-disposalproblems, and as a means of conserving a natural resource.

Introduction
There is a general belief among those engaged in the secondary recovery of oilby water-flooding that one of the most important requirements for the successof any such project is an adequate supply of good, fresh water. Fresh watershave the advantages of being more easily stabilized than salt waters and ofbeing usable about the lease for all purposes. The use of brines forwaterflooding never has been given much consideration in the Pennsylvania Gradearea. The use of brines in Mid-Continent operations has been considered largelyas a substitute for fresh waters, which were economically unobtainable for manyoperations.
Estimated recoveries for some water" drive fields indicate that less of theoriginal oil in place will be left upon abandonment than with the above-averagepractices used in Pennsylvania Grade water-flood operations. Lower residual oilsaturations than 25 pet of the pore space following the water-flooding of ThirdBradford sand cores in the laboratory are unusual. In comparison, water-flushedsands surrounding any virgin oil pool are found to be practically devoid ofoil.
T.P. 2127
A Study of Some Factors Affecting Gun Perforating
Authors: Oliphant S.C. , Farris R. Floyd 
Published: June 2014

Abstract
Presented in this paper is a summary of the results of experiments conducted inboth the laboratory and the field during the past three years in connectionwith casing-perforation problems. Included are studies of gun features thatinfluence bullet performance and penetration, and studies of the effect ofperforator bullets on casing and the neat cement in the annulus. Discussion anddata are also presented relative to the accuracy of depth measurements in deepwells.

Introduction
It is a common practice in the oil industry to effect the completion of oilwells by setting and cementing casing through the production horizons andperforating the section of casing opposite the desired interval by means of agun lowered into the well on a cable or on the tubing. This practice has beenfollowed for some time, and this method of completion has been givenconsiderable study by the companies that render perforating service as well asby the oil companies that utilize their services. Through continued research onthis subject, it has been possible to develop guns, bullets, and powder thatwill permit controlled firing at great depths, and penetration of as many astwo strings of casing. It is the object of this paper to present the results ofstudies made of gun perforating in both the field and the laboratory. Thesestudies were made to determine the factors that affect penetration of thebullet, burring of the casing, accuracy of depth measurements, and other items.It is hoped that by presenting the results of these investigations a betterunderstanding may be obtained of certain of the factors involved in gunperforating and further investigation of the subject will be prompted.

Subsurface Tests
A well approximately 9000'Ft. deep, which was being prepared for abandonment, was selected for subsurface tests of gun-perforating experiments, In preparingthe well for the experiment, 5 ? in. casing in the hole was pulled and rackedin the derrick. A test section of pipe, which consisted of 65 ft. of 5 in. 18lb. J-55 casing centered inside 7 in. 28 lb. N-80 casing, was placed in thederrick corner and the annulus between the two pipes was cemented from thebottom up with 16 ? lb per gal neat cement, which was mixed and displaced witha cementing truck in the usual manner. After the cement had been allowed toharden for about a week, the test section was lowered into the hole in the 5 ?in. casing to a depth of 6600'Ft. by casing measurements. The hole was filledwith drilling fluid weighing 10 lb per gallon.
A perforating company was called to perforate the pipe, but was not advisedthat an experiment was being conducted.
T.P. 2115
Phase Behavior in the Methane-ethane-n-pentane System
Authors: Billman G.W. , Sage B.H. , Lacey W.N. 
Published: June 2014

Abstract
The composition of the coexisting phases in the methane-ethane-n-pentane systemwas determined at 100'F. This was accomplished by withdrawing samples of thecoexisting phases under isobaric-isothermal conditions. The relative amount ofeach of the components present in the liquid and gas phases was determined byconventional analytical fractionation methods. The phase behavior of thissystem approximates that estimated from generalized correlations which takeinto account the influence of the nature and amount of each of the componentspresent upon the equilibrium. It was found that for particular pressures andtemperatures the equilibrium constant of each of the components was influencedsignificantly by the composition of the system and this effect was morepronounced at the lower pressures for methane than for the components ofgreater molecular weight. However, at the higher pressures approaching themaximum two-phase pressure for the system at this temperature the compositionmarkedly influences the equilibrium constants of all the components at aparticular pressure and temperature. The results of this study are presented ingraphical and tabular form.

Introduction
The phase behavior of many of the binary systems containing paraffinhydrocarbon components from methane through n-pentane has been investigatedduring recent years. In addition the compositions of the coexisting phases inmixtures of crude oil and natural gas have been studied.
However, these results do not establish the influence of the nature and amountof the other substances making up a multicomponent system upon the gas-liquidequilibrium constant of anyone component. A preliminary correlation on thebasis of values for binary systems was made utilizing such experimentalinformation as was available. However, there is need for much additionalinformation regarding behavior in systems containing more than twocomponents.
Study of the phase behavior of ternary systems offers a feasible attack uponthe determination of the influence of composition as well as of pressure andtemperature upon the several equilibrium constants concerned. An investigationof the phase behavior of the methane-propane-n-pentane system at 100?, 160?, and 220'F was reported. This work served to illustrate the marked influence ofconcentration of the other components upon the equilibrium constants.Variations of as much as $0 pet in the equilibrium constants for methane forfixed temperature and pressure were observed in regions remote from thecritical state. Likewise there was a marked variation in the equilibriumconstants of propane and n-pentane as a result of changes in the composition.These results indicated the desirability of investigating additional ternarysystems. The present paper deals with a study of the methane-ethane-n- pentanesystem at 100'F, which is similar in many respects to the work upon themethane-propane-n-pentane system cited above.
T.P. 2232