bluuebunny/crossref_metadata_2025_split huggingface dataset:
Performance of the Lower Pawelek Reservoir, Falls City Field, Karnes County, Texas
Authors: Crutchfield John W. , Bowers Emil F. 
Published: April 2012

Abstract
This paper presents the initial results of a pressure maintenance by waterreturn project in the Lower Pawelek reservoir of the Falls City Field, KarnesCounty, Southwest Texas. Production is from the Lower Wilcox section at anaverage depth of 6,030'Ft on the downthrown side of a "down to thecoast" fault. Of particular interest is that the reservoir oil is highgravity and low viscosity but far undersaturated with gas at the originalreservoir pressure and temperature. The early pressure and production historyindicated only a partial or limited water drive, and this fact, coupled withthe characteristics of the reservoir fluid and artificial lifting problems, made advisable the water injection program to maintain reservoirpressure.
The paper includes a description of the reservoir and reservoir fluids, thepressure and production history, a description of the water injectionfacilities, and the results of reservoir calculations involving Hurst'sunsteady state flow and the material balance equations for calculation of waterinflux and prediction of the pressure-production relationship at various ratesof withdrawal.
The reservoir calculations and initial field results indicate that reservoirpressures in excess of 85 per cent of original pressure can be maintained bycontrol of water injection even at very high rates of production.

Introduction
The purpose of this paper is to report the initial results of a pressuremaintenance by water return program in the Lower Pawelek reservoir, Falls CityField, Karnes County, Texas, and to calculate an empirical relationship betweenpressure and production in this limited or partial water drive reservoir.

Discussion

Location
The Falls City Field (Fig. 1) is located two miles north of the town of FallsCity in Karnes County, Texas, and is approximately 50 miles south-southeast ofSan Antonio on U. S. Highway 181.

Discovery and Development
The initial block of leases was taken after a surface geological surveyidentified a major east-west fault and closure on the south or downthrownsection. The discovery well, Southern Minerals Corporation's Joe F. Bartosch 1, was completed at 4,650'Ft in the Lower Bartosch sand in December, 1944.Drilling was continuous until December, 1946, and resulted in the discovery of12 oil reservoirs between 4,600 and 6,050'Ft in the Middle and Lower Wilcoxformations.
T.P. 2937
Correlation of Bottom Hole Sample Data
Authors: Borden Guy , Rzasa Michael J. 
Published: April 2012

Abstract
Laboratory data on bubble point pressures and reservoir volume factors havebeen correlated as functions of solution gas-oil ratio, calculated gas gravityof the pentanes-and-lighter fraction of the entire fluid, differential residualoil gravity, and reservoir temperatures.

Introduction
Several correlations of crude oil properties have appeared in theliterature.
D. L. Katz in 1942 presented five methods of predicting oil shrinkage, thesebeing of decreasing accuracy for decreasing amounts of informationavailable.
M. B. Standing in 1947 published three correlations of laboratory flashvaporization data of California crudes. From values of GOR (gas-oil ratio), gasgravity, liquid gravity, and temperature, his correlations will predict bubblepoint pressure, formation volumes of bubble point liquids, and two-phaseformation volumes.
Curtis and Brinkley in 1949 presented several correlations. From the gas-oilratio, an approximation of reservoir volume factor and barrels of condensaterecoverable per barrel of reservoir space may be obtained; along with liquidgravity and reservoir temperature, the GOR will allow prediction of bubblepoint pressure. These last correlations seem to be more qualitative thanquantitative.
Generally, laboratory bottom hole sample tests furnish information on solutiongas-oil ratios, residual oil gravities, bubble point pressures, viscosities ofoils, liquid shrinkages, and occasionally gas gravities. Each of these data hasits own applications and use in reservoir engineering calculations. Theparticular uses of correlated bottom hole sample data are found inProviding a basis for obtaining estimates of formation crude propertiesin fields where bottom hole sampling is impractical or impossible.Greatly reducing the time in obtaining the desired information.Determining the applicability of the results from various bottom holesamples to particular field problems.Avoiding, in many cases, the uncertainties of sampling by replacing it withan element over which greater control can be exercised.Permitting use of preliminary field data in application of productionprocedures before a bottom hole sample can be obtained and analyzed in thelaboratory.Serving as a check on data which may appear out of line.Estimating for a particular type crude the appropriate equilibriumconstants by working backward from the bubble point pressure.Estimating original or other past history properties of reservoirs thatwere not sampled in the past.
T.P. 2931
The Effect of Permeability Stratification in Complete Water-Drive Systems
Authors: Muskat Morris 
Published: April 2012

Abstract
A theory is presented for calculating the performance history of completewater-drive systems producing from idealized stratified formations. The generalequations are applied to systems where the permeability stratification iseither of the exponential or linear type. Calculations were carried through fordifferent degrees of permeability stratification, but with special emphasis onthe effect of the mobility ratio between the produced oil and the invadingwater on the resultant performance. These results are also expressedgraphically as curves for the initial water breakthrough recovery, for thedifferent degrees of stratification, as a function of the mobility ratio, andof the composition of the produced fluid stream as a function of the cumulativeoil recovery. For several typical cases the latter has also been plotted as afunction of the cumulative oil and water through-flow. The general result isthat when the mobility of the oil is lower than that of the invading water thechannelling tendency resulting from the permeability stratification becomesaggravated as the higher permeability zones become flooded out. Situations ofthis type would obtain when producing low gravity or highly viscous oils.Conversely, if the mobility of the oil is high compared to that of the invadingwater, the flooding of the high permeability zones will lead to a retarding andchoking effect, and the gross bypassing phenomena will be partially suppressed.These conditions would correspond to those of flooding high gravity or lowviscosity oils. A discussion is given of the various basic assumptions made inthe analysis, including that of ignoring the stripping phase of the productionhistory as implied by relative permeability concepts.

Introduction
The physical ultimate recoveries from oil reservoirs are basicallydetermined and limited by the physical oil displacement processes associatedwith the reservoir producing mechanism. In practice, however, the economicultimate recoveries are further limited by the mobility of the reservoir fluidsand the uniformity and continuity of the producing formation. In fact, it isthe differential depletion between the component parts of the compositereservoir which ultimately determines the total recovery at the time of fieldabandonment.
T.P. 2894
Stainless Steel Containers for Laboratory Drilling Mud Test Work
Authors: Lilienthal W.B. 
Published: April 2012

A considerable saving in time and money has been effected by use of aspecially designed stainless steel container for laboratory drilling mud testwork. This container involves use of a standard tall-form stainless steelbeaker for service in which the mud sample is heated to an elevated temperatureand maintained there for protracted periods of time, while undergoing agitationto facilitate mixing of mud components. Agitation is accomplished by rotatingthe filled containers on motor-driven rollers within an oven. Several porcelainballs are generally placed in the containers to further improveagitation.
Soft glass containers (Mason jars) were used in this service in early work, andwere found to be unsuitable for the following reasons:Poor resistance to thermal shock.Containers could withstand only relatively low pressures.Accidental breakage in handling.Chemical deterioration and subsequent mud contamination from reaction ofhigh pH muds with the glass at elevated temperatures.
Pyrex containers were also considered, but, inasmuch as they providedimprovement only in items 1 and 4 listed above the additional cost was notbelieved to be justified.
A scale drawing of the container is shown in the figure illustrating details incross-section. A pressed stainless steel lid was fabricated to match the rollededge of the beaker top, and male and female screwed connections external to thecontainer were made up to complete the closure with the O-ring used as a gasketbetween the lid and beaker.
T.N. 56
Interpretation of Capillary Pressure Data
Authors: Purcell W.R. 
Published: April 2012

In a previous technical note by Walter Rose, evidence is offered in supportof the contention that "the possibility of describing oil recovery featuresin terms of capillary pressure phenomena has not been establishedentirely." It is not the purpose of this note to present further discussionof this possibility but rather to point out that the argument presented theredoes not appear to be generally valid.
In the cited note reference is made to the experiments of Welge wherein it wasshown that when water was displaced by oil from a core the pressure in thewater phase was less than in the oil phase but that when this oil was thenproduced by water drive the pressure in the water phase was greater than in theoil phase. Rose has concluded from these observations that conditions of staticequilibrium did not obtain since the fluid saturations were such that phasediscontinuities seemed unlikely. The argument from which this conclusion wasdrawn is based on the contention that "the pressure is always greatest inthe non-wetting phase at each static interstitial interface of contact with thewetting phase." This premise appears to have been reached from aconsideration of capillary phenomena in cylindrical tubes, although it may alsohold for other types of pore geometry, but as will be shown below it does nothold for all pore shapes and hence is not generally applicable.
Since the pore structure of porous media such as reservoir rocks is in generalso complex as to defy exact description, it is undoubtedly of great value toestablish a model in terms of pore shapes of known geometry, provided of coursethat the limitations of the model are recognized. That the limitations of thecapillary, or cylindrical tube model have not always been fully recognized willbe evident from the following discussion of a pore of different shape but onewhich may as logically be considered as the capillary tube.
T.N. 60
A Study of the Dornick Hills-Springer Sand Reservoir, Velma Pool, Oklahoma
Authors: Davis W.B. 
Published: April 2012

Abstract
This paper presents a summary of the results of a study of the DornickHills-Springer sand reservoir of the Velma Pool, Stephens County, Oklahoma. Thedata are of interest because this type of reservoir is unusual in themid-continent area.
The reservoir is characterized by very steep dips and a relatively thickproducing section. Its up-dip productive limit is defined by truncation of theproductive sands, and the down-dip limit is defined by deterioration of sandquality rather than by the presence of an oil-water contact. The crude oil isof 29' API gravity, is relatively viscous and was saturated with dissolved gasat the original reservoir pressure.
Consideration of the physical characteristics of the reservoir indicatesthat natural water encroachment will be negligible, and that the producingmechanism will be a dissolved gas drive augmented by gravity drainage.Performance to date tends to confirm this.

Introduction
It is the purpose of this paper to present some of the features of theDornick Hills - Springer sand reservoir which are unusual in mid-continentoperations. The study was undertaken in an attempt to define the producingmechanism or mechanisms that will control reservoir performance, as an aid indetermining well completion and production practices.

Geology
The reservoir under consideration is a series of sand bodies ofPennsylvanian age found in the Lower Dornick Hills and/or Springer formations.For the purpose of this paper, the sand series is referred to as the DornickHills-Springer sand.
This sand series lies on the northeast flank of the Velma anticline, and dipsvery sharply to the northeast in TWP 1S-5W, the average dip being about 45'.However, as shown in Fig. 1, the trend of the pool swings eastward in TWP 1S-4Wwith a coincident decrease in dip angle. In this portion of the pool theaverage dip is about 25'.
T.P. 2999
Capillary Pressure Investigations
Authors: Brown Harry W. 
Published: April 2012

Abstract
This paper presents results of static capillary pressure measurements madeboth by the restored-state and by the mercury-injection methods, and of dynamiccapillary pressure measurements made by the Hassler technique.
The results indicate a variation from sample to sample of the factor used toconvert capillary pressure obtained by mercury injection to those applicable toa water-gas system. Static capillary pressures measured by the restored-statemethod were found to be in close agreement with dynamic capillary pressures, indicating that data obtained from static measurements may be utilized withconfidence in the solution of dynamic problems of fluid flow.
Experimental data are presented on the use of "J-curves" for thecorrelation of capillary pressure-saturation relations for a number of coresfrom a particular geologic formation. It is shown that the correlation wasimproved in some cases by restricting it to certain lithologicclassifications.

Introduction

The Meaning and Importance of Capillary Pressure
The coexistence of two or more immiscible fluids within the voids of aporous medium, such as reservoir rock, gives rise to capillary forces. Becauseof the interfacial tension existing at the boundary between two immisciblefluids in a pore space, the interface is curved, and there is a pressuredifference across the interface. This pressure difference is termed thecapillary pressure.
The magnitude of the capillary pressure between two immiscible fluids whichtogether fill a porous medium depends upon several factors: the texturalproperties of the medium, the wettability of the medium, the interfacialtension between the fluids, the respective saturations of the fluids, and themanner in which these saturations are attained. For a given pair of immisciblefluids in a particular sample of reservoir rock, the capillary pressure is aunique function of the fluid saturation, provided that the saturation of thefluid which wets the rock has previously been decreased unidirectionally froman initially complete saturation.
T.P. 3025
Relative Permeability to Liquid in Liquid-Gas Systems
Authors: Rapoport L.A. , Leas W.J. 
Published: April 2012

Abstract
As a preliminary, consideration is given to the conventional definition ofrelative permeability and to the conditions governing the simultaneous flow ofoil and gas through porous media.
For the conditions of flow prevailing throughout most of a gas drivereservoir, the oil and gas can reasonably be supposed to be in capillaryequilibrium with each other. Under these conditions, and these conditions only, the relative permeability to liquid can be expressed as a function ofsaturation. The relative permeability to liquid in that case is dependent uponthe distribution of fluids which itself is shown to be related to the capillarypressure, and, in turn, to the saturation. As a consequence, relativepermeability to liquid can be expressed in terms of the volume and surface areaof a network of liquid channels bounded by the rock and the gas phase. Whilethe volume of this network can be evaluated accurately, the surface areacannot. However, for any such volume, maximum and minimum values of thecorresponding surface area can be calculated from capillary pressure data. Itis then possible to establish for any saturation the limits within which thevalue of the relative permeability to liquid must lie.
As a consequence of the theoretical development, the validity of anexperimental method for measuring relative permeability to liquid whichutilizes a stationary gas phase is demonstrated. In this method capillarybarriers are cemented to the ends of the core sample to permit the maintenanceof capillary equilibrium between the two phases. At the same time, thisprocedure eliminates undesirable secondary phenomena such as end effects, fissure effects, etc., the presence of which adversely affect the results ofother laboratory methods.
The results obtained by theoretical calculations, and experimentally, arediscussed. In view of the overall precision that can presently be obtained inreservoir calculations, the agreement between the calculated and measuredrelative permeability to liquid data can be considered satisfactory.
In conclusion, for reasons of economy and simplicity, the procedure ofcalculating limiting relative permeability to liquid curves from capillarypressure data is indicated for general engineering purposes. It is shown thatthe above procedure can easily be extended to the cases where connate water ispresent. Its use for reservoir studies is particularly recommended inconjunction with the method for measuring relative permeability to gas whichsimultaneously yields the capillary pressure data necessary for thecalculations.
T.P. 3021
Experimental Investigation of Factors Affecting Laboratory Relative Permeability Measurements
Authors: Geffen T.M. , Owens W.W. , Parrish D.R. , Morse R.A. 
Published: April 2012

Abstract
Laboratory studies of several factors affecting measurements of relativepermeability were made using the three-section plastic-covered core technique.Results show that the core assembly, properly constructed, will perform as asingle unit, and that the testing technique will, under suitable conditions ofpressure gradient, gas expansion, and migration of partial water saturation, permit measurement of flow characteristics not affected by technique.Wettability equilibrium is readily established in cores exhibiting strongwetting preference to water or oil when initially saturated with water.Laboratory tests must be conducted so that saturation changes represent thosethat occur in the reservoir. Immediate implications of saturation history arethat the possibility exists of increasing the displacement efficiency ofsolution gas drive reservoirs over the natural process, andresidual gassaturations following water flooding in gas or gas condensate reservoirs willbe 15 to 50 per cent pore space rather than 1 to 11 per cent as generallybelieved.

Introduction
Solutions of petroleum reservoir problems pertaining to productionperformance require the use of true relative permeability characteristics. Thisrelationship of fluid conductivity and saturation has been obtained byreservoir engineers in four ways, namely:From past gross reservoir performance and the extrapolation of this databased on experience,By using published fluid flow relationships obtained in laboratory studieson general type porous materials,By attempting a mathematical derivation of flow behavior, using someexperimentally obtained characteristics of reservoir rocks, andBy laboratory flow tests using representative rock samples of areservoir.
The first three methods listed above have shortcomings which make their uselimited or questionable. Production characteristics of only certain processesare obtained from field data and these are not available at the beginning of areservoir's producing life, at which time they are desirable. It is fortuitousif general fluid flow characteristics obtained experimentally have accurateapplication to specific field problems. Also, it is felt that at this timethere is not sufficient knowledge of the flow behavior of oil, water, and gasin porous materials to enable applicable analytical description of this to bemade based on other measured rock characteristics.
Measurement of relative permeability in the laboratory offers the only directmethod subject to adequate checking for determination of flow characteristicsapplicable to field problems. Primarily, this paper deals with laboratoryexperiments to establish the effects of several factors on the measurement ofrelative permeability and the practical significance of this knowledge.
T.P. 3053
The Shuler Jones Sand Pool; Nine Years of Unitized Pressure-Maintenance Operations
Authors: Tarner Jack , Evans W.R. , Kaveler H.H. 
Published: April 2012

Abstract
The geological features, development history and engineering detail of theShuler Field and the results of approximately two years of unitized operationof the Shuler Jones Sand Pool, were discussed in a prior publication. Thepurpose of this paper is to present the results of pressure maintenance in theShuler Jones Sand Pool after nine years of unit operation.

General Information
The Shuler Jones Sand Pool is located in and about Section 18, Township 18South, Range 17 West, Union County, Ark. The pool was discovered in September,1937, unitized in February, 1941, and subjected to gas injection operations inJuly, 1941. Water was first returned to the reservoir in July, 1944.
The reservoir is an anticlinal trap covering about 4,000 acres. The 154,000acre-ft of sandstone initially consisted of approximately 150,000 acre-ft ofproductive oil zone and 4,000 acre-ft of gas-cap. The average depth ofproduction is 7,400'Ft. Maximum closure of the reservoir is 135 ft and the oilcolumn lies between a gas-oil contact at -7,270'Ft and a water-oil contact at-7,370 to -7,380'Ft. The field is approximately four miles long, east and west, and one and one-half miles wide.
The sand grains are angular and vary from fine to medium size. The porosityof the sandstone averages 20.2 per cent. The specific permeability averages 400md. Some zones have as high as 30 per cent porosity and specific permeabilityof 4,000 md. The reservoir rock is not uniform in character but consists ofsandstone zones interspersed with shale. The variation in rock characteristicsis evident in the electric log and core analyses presented in the originalpublication. Asphalt present in the pore space of the sandstone limited thereservoir to the southeast and apparently blocked any encroachment of waterfrom that direction.
The initial reservoir pressure at a subsea depth of 7,300'Ft was 3,520 psi.The reservoir temperature was 198?F. Initially, the solution gas volume was 765cu ft per bbl and the reservoir volume factor was 1.45. The equation for thegas volume factor presented is based on a direct measurement of a sample of thegas and is a correction of that used in the original paper.
The gravity of the oil produced is from 32 to 34? API.
T.P. 3054