bluuebunny/crossref_metadata_2025 huggingface dataset:
Design and Operation of the Dehydration Facility for the Elsinore "73" No. 1, a CO2 Supply Well
Authors: Skopak J. E. , Phillips L. A.
Published: December 2007

A carbon dioxide (CO2) supply well was drilled and completed by Conoco Inc. in the Elsinore Field, Pecos County, Texas in September, 1983. The well was drilled to provide CO2 for the Ford Geraldine (Delaware Sand) Unit, Reeves and Culberson Counties, Texas. The well tested flowing 11.5 MMCFPD of saturated CO2 at a pressure above the critical.

The corrosive nature of the saturated CO2 at a pressure above the critical necessitated a careful study of pipelining and dehydration options. Ultimately, the CO2 would have to be dehydrated, since it would be moved to the Ford Geraldine Unit through an existing unprotected steel pipeline.

This paper details the design and operation of the Elsinore "73" No. 1 CO2 dehydration facility. Specific topics that will be discussed are pipelining and dehydration alternatives, molecular sieve (mol sieve) bed design, equipment and piping, metallurgy, fuel options, automation and startup.
A New Sonic Array Tool for Full Waveform Logging
Authors: Morris C. F. , Little T. M. , Letton W.
Published: December 2007

For over 20 years, sonic logging has implied compressional velocity logging using first break detection from two-receiver tools. Today, sonic logging techniques can utilize more of the information contained in the acoustic waveform to provide shear and Stoneley-wave velocity and attenuation measurements. This requires signal-processing techniques for full-waveform analysis. These techniques generally need more spatial samples of the wavefield than are provided by standard two-receiver tools. To fulfill this need, a new multireceiver sonic tool has been designed.

In this paper, we describe a new sonic array tool which has an array of eight receivers spaced 6 in. apart, located 8 ft from the nearer of two transmitters. In addition to array capabilities, standard short and long-spaced sonic logs are available. A special section has been incorporated to give a mud-velocity measurement. The downhole electronics provide digitized waveform acquisitions with an effective resolution capability of 11 bits.

To extract the additional answers from the full waveform, slowness-time coherence (STC) processing has been developed. Based on semblance techniques, STC identifies coherent arrivals across the array. Examples of waveforms and processed logs from both open and cased wells are presented to illustrate the tool's capabilities.
Effect of Interference on Pressure Build-Up - A Method for Calculating Porosity-Thickness Product
Authors: Collins R.E. , Kolodzie P.A.
Published: December 2007

The purpose of this paper is to present the results of a theoretical study of the effect of interwell interference on pressure buildup in a shut-in well in multi-well reservoirs. An equation was developed which describes pressure buildup in a homogeneous, infinite reservoir of uniform thickness containing a single, mobile fluid which is slightly compressible. Using this equation, the pressure buildup in a shut-in well in a reservoir containing a number of offset producing wells was calculated on an electronic digital computer. For this study the offset wells had specified,, variable production rates. These computations illustrate the nature of pressure interference during pressure buildup tests.

The study shows that offset producing wells can cause appreciable pressure drawdown at a shut-in well. The existence of interference does not obviate the use of the conventional Horner technique for estimating permeability and static well pressure from pressure buildup tests.

A method is derived for calculating the average porosity-thickness product for a reservoir from a change in pressure interference which is induced by altering production rates of offset wells. Information required for this calculation includes the change in pressure interference, slope of the buildup curves, average fluid compressibility, well locations, and production histories of all wells. An analysis was made of the error in porosity-thickness product resulting from errors in pressure measurements and other factors required in the calculations.

Introduction

Pressure buildup tests have been used for a number of years to determine the static bottom-hole well pressure. More recently, these tests have also been used the average reservoir permeability in the drainage area of the shut-in well. Perhaps the most widely used method for interpreting pressure buildup data to obtain the static pressure and average permeability is the one proposed by Horner, based on the theoretical analysis of pressure buildup in a single well in an infinite reservoir.
A Unified Approach to Devonian Shale Oilwell Development
Authors: Gottschling J. C. , Cecil K. L. , Wright J. N.
Published: December 2007

The completion program for a Devonian Shale oil well should consider the unconventionality of the reservoir. Each, step from drill site selection to production method must be designed to minimize disturbance of the natural fracture system. This paper will present a systematic approach to Devonian Shale oil well development in one particular area. Short term production results presented show a less drastic decline rate than typically associated with shale oil well production. The merits of a well planned, systematic program will be evident.
The Use of Lineament Mapping and Electromagnetic Surveying for Detecting Natural Fractures in the Devonian Shale
Authors: Weaver K. A. , Cress W. D.
Published: December 2007

The natural fractures existing in the Devonian Shale of the Appalachian Basin provide the enhanced permeability necessary to make the shale economically productive. Lineament maps are the predominent means of tracing fractures at the surface, but interpretation errors that are associated with their construction limit their accuracy. This study uses an electromagnetic surveying technique to eliminate these inaccuracies. The first five wells sited with the aid of this method have all intersected fractures. Such surveys appear to be useful for optimizing the location of wellsites.
Investigations Into Devonian Shale Gas Production Mechanisms in Southern Ohio
Authors: Thompson T. W. , McBane R. A. , Sitler Gary , Strawn Jon , Moody Mark
Published: December 2007

Economic gas production from the Devonian Shale requires permeable pathways combined with matrix storage. These pathways may include fractures, bedding planes or silt layers. The Gas Research Institute is sponsoring a research project to evaluate the relationships these geologic features and productive gas flows have with the eventual aim of developing better exploration, stimulation and production strategies. This study will investigate wells throughout the basin, with a wide range of potential productivity in order to determine what variations in geology result in marginal versus good producers. As a first phase of this project, detailed data on the geology and reservoir parameters are being collected on four wells in southern Ohio, which are being recompleted in the Devonian Shale. Two additional wells have been investigated in a pilot study, the remainder are currently under investigation.
Paraffin Control More Cost-Effective
Authors: Addison G. E.
Published: December 2007

Paraffin control by the thermal and mechanical means that have predominated in the past have done so relatively independent of their cost effectiveness or long term adverse effects. Economic conditions in the industry now require more attention and expertise be applied to solving paraffin problems. Tests and procedures now known allow more efficient use of paraffin control dollars.
The Effect Of Permeability Discontinuities On Pressure Build-Up Behavior
Authors: Murphy W.C.
Published: December 2007

This paper presents a study of certain permeability discontinuities as observed in drill-stem test pressure build-up behaviors Pressure build-up anomalies, under unsteady-state conditions, were investigated to determine the type and relative location of discontinuities in the formation. These anomalies are identified by an interpretation of the build-up behavior and extrapolation plot and confirmed by field results.

Illustrations are submitted on permeability reduction at the wellbore resulting from formation damage, deep mud invasion, after- production, vertical permeability, permeability reduction, and linear barriers. A practical analogy of these discontinuities is made to show their immediate relation to the test and the probable ultimate reaction of the producing zone.
Wellhead Control Dispatched From One Control Center
Authors: Boggs R.E.
Published: December 2007

Publication Rights Reserved

This paper is to be presented at the SPE Regional Meeting in Liberal, Kansas, November 18–19, 1965, and is considered the property of the Society of Petroleum Engineers. Permission to publish is hereby restricted to an abstract of not more than 300 words, with no illustrations, unless the paper is specifically released to the press by the Editor of the Journal of Petroleum Technology or the Executive Secretary. Such abstract should contain conspicuous acknowledgment of where and by whom the paper is presented. Publication elsewhere after publication in Journal of Petroleum Technology or Society of Petroleum Engineers Journal is granted on request, providing proper credit is given that publication and the original presentation of the paper.

Panhandle Eastern Pipe Line Company has long been aware of the advantages of being able to remotely control the flow of natural gas from various fields to meet sudden demand changes in our marketing areas. Transmission systems are designed and constructed to provide the required volume of gas demanded at any time, regardless of the weather or sudden changes therein, even though the peak domestic and industrial loads may occasionally be many times the average load. In order to meet peak demands the system makes use of its auxiliary facilities, such as storage fields that during the periods of slack demand have been filled with gas. High transmission line pressures also help to fulfill the peak demands, resulting from the high degree of compressibility of the gas itself. A sudden change in the weather in the marketing areas is not the only reason for a sudden need for additional gas volumes. The temporary loss of a compressor unit or a section of the pipeline can result in the sudden demand for more gas from another area. Unfortunately, the additional amounts of gas that can be obtained from these aforementioned facilities is limited and additional gas must be obtained from the producing areas if the peak demand persists. Under present operations when a gas well has to be turned on or shut-in, this must be done manually by a fieldman.
On a Convergence Criterion for Linear (Inner) Iterative Solvers for Reservoir Simulation
Authors: Diaz J. C. , Jines W. R. , Steihaug T.
Published: December 2007

In reservoir simulation, the discretization of the fluid flow and energy equations generates systems of nonlinear algebraic equations. These equations are solved using Newton-Raphson iteration. This method works from an approximation, generating a linear sparse system of equations whose solution correct the current approximation. This process is repeated until a satisfactory solution of the nonlinear system is found. In practice, each linear system is solved with an iterative method. The overall efficiency of the simulator depends upon the stopping criteria for the linear (inner-) iteration and the termination rule for the nonlinear (outer-) iteration. In this article, stopping criteria for the inner-iteration in terms of the nonlinear requirements are discussed. The design of an optimal criterion includes knowledge of the approximate location of the regions of linear and quadratic rates of convergence for the nonlinear (outer-) iteration. A comparison of several stopping criteria is given. Their effect on CPU time, number of outer-iterations and time step selection is illustrated. Criteria using relaxed constraints in the linear convergence region are more efficient. The presentation is in the context of block-preconditioned iterative methods for thermal simulation.
Black Lake Field A Study In Conservation And Development Natchitoches Parish, Louisiana
Authors: Sawyer J.R.
Published: December 2007

The Black Lake Field is located in Township 11 North, Range 6 West in Natchitoches Parish, Louisiana, on the southeastern flank of the Sabine uplift. Geographically the field is located between Black and Saline Lakes approximately 60 miles southeast of Shreveport and 15 miles northeast of the town of Natchitoches.

This is an area that had defied Operators for years. Prior to 1947 drilling had been restricted to shallow depths, but from 1947 to 1958 six (6) wells were drilled within a 7 mile radius of Black Lake to a depth of 8000 feet or deeper. The first of these deeper tests was the U. S. Forest Reservation #F-135, drilled by H. L. Hunt in January, 1947, in Section 35, T-11-N, R-5-W. Continental Oil Company then drilled three (3) wells, the Pardee #1, Section 30, T-12-N, R-6-W in July 1948; the Bank of Bastrop #1, Section 18, T-12-N, R-6-W in September, 1949; and the Edenborn #1, Section 27, T-12-N, R-6-W in November, 1949. Interest in the area died down until July, 1958, when F.R. Jackson drilled in Section 26, T-11-N, R-7-W the Franklin Realty #1. The Nebo Oil Company followed with the G. H. Monrose #1 drilled in Section 28, T-11-N, R-5-W in December, 1958. Although none of the wells were productive, the wells to the south and southeast had good development of Pettit porosity. This porosity development was not evident in the wells to the north, west, and northwest indicating the possibility of a stratigraphic trap for the accumulation of hydrocarbons.

Placid Oil Company began leasing in the area in the spring of 1963 and after obtaining sufficient acreage Geophysical crews were brought in to obtain seismic information. Based on a combination of seismic and subsurface data, Placid spudded the Edenborn #1 in Section 25, T-11-N, R-6-W on October 3, 1963. After drilling to a depth of 8359 feet the well was abandoned; however, because of the development of the Pettit porosity and the numerous oil shows in the cores, the Edenborn #2 was spudded February 13, 1964, three (3) miles north in Section 12, T-11-N, R-6-W.

The Edenborn #2 blew out while drilling into the Pettit and after spending nearly a month fishing, the well had to be abandoned due to mechanical difficulties in the hole. The rig was skidded 100 feet north and the Edenborn #2-A was completed May 25, 1964, flowing

P. 1^
A General Purpose Single-Phase Naturally Fractured (Carbonate) Reservoir Simulator With Rigorous Treatment of Rock-Stress/Fluid-Pressure Interactions and Interporosity Flow
Authors: Leung W. F.
Published: December 2007

A rigorous fully implicit numerical reservoir simulator has been developed to model single phase fluid flow in deformable naturally fractured or carbonate reservoirs. The present formulation represents a great improvement over existing simulators for fractured reservoirs in that many of the limiting assumptions have been removed. The interactions of rock stress, matrix pore pressure, and fracture pressure; bulk rock volumetric expansion effects; unsteady matrix-fracture flow; vug-matrix and vug-fracture flow; and the matrix and fracture anisotropic flow have been rigorously modelled. An interesting comparison in modeling fractured reservoirs is made between the present volume average approach and the deterministic approach where the matrix and fracture geometries are fixed. A parametric study reveals the new finding that the rock-stress interaction effects may modify significantly the compressibility of the fractured rock which would then affect the characteristic behavior of the pressure transients of a fractured reservoir. The stress sensitive permeability effect for the fractures is also determined to be important. It is shown through numerical examples that existing dual porosity models are inadequate to model a vuggy fractured reservoir where the solution vugs are intersected by the fracture network of the reservoir. A field example is used to demonstrate how a detailed geometrical description of the fractured blocks may be obtained by matching the simulated pressure transient behavior of the well test data.
Modelling the Effects of Shales on Reservoir Performance: Calculation of Effective Vertical Permeability
Authors: Begg S. H. , King P. R.
Published: December 2007

In this paper we present four methods of estimating the effective vertical permeability of a reservoir containing stochastic shales in both two and three dimensions. The methods vary in their accuracy, speed and range of applicability. The first is based on numerical simulation, the second is an analytical method, the third and fourth are based on calculating approximate streamline lengths. The methods give consistent results for similar models and are used to show that the effective vertical permeability is strongly dependent on the shale dimensions, shale fraction and layer thickness. It is also shown that the results of the two-dimensional models are inappropriate even when the megascopic flow is unidirectional.
A Chemical Displacement Model for Alkaline Steamflooding in Linear Systems
Authors: Okoye C. U. , Kou-Jou C. , Tiab D. , Hayatdavoudi A.
Published: December 2007

A chemical equilibrium flow model that incorporates conductive and convective heat transfer is presented for continuous alkaline steam flooding of acidic oils in linear systems. The chemical aspect of the model consists of the chemistry of acid hydrolysis at elevated temperatures, resulting in in-situ generation of surfactants and the interaction of the alkali with reservoir rock at high temperatures, leading to alkali consumption. The adsorption and desorption of active species at the interfaces are expressed as ionic processes using the Gouy-Chapman theory of diffuse double layers.

The model predicts that the surfactant slug generated in-situ in alkaline flooding increases with temperature and that, while adsorption of surfactant increases with temperature, there is a net increase in surfactant slug size to recover otherwise immobile oil, leading to higher oil recovery.
Drilling and Completion of Khuff Gas Wells, Saudi Arabia
Authors: Turki W. H.
Published: December 2007

This paper will review the program for drilling and completing the primary well configurations for 4-1/2 in. (114.3 mm) and 7 in. (177.8 mm) Khuff gas completions in Saudi Arabia.

The drilling programs associated with these configurations and the typical drilling problems and geological considerations relevant to casing point selections will be outlined, as well as types, weights and grades of casings typically run. In addition, drilling fluids, cementing programs and wellhead equipment will be reviewed.

Finally, completion procedures will be discussed and drilling performance to date will be reviewed showing improvement since initial wells were drilled.
Environmental Factors Affecting the Movement and Dispersal of Oil Spills with Particular Reference to the Gulf
Authors: Lynagh N.
Published: December 2007

Currents, tidal streams and winds all influence the movement and dispersal of oil spills. Examination of the surface circulation and wind climate of the Gulf highlights the coasts most likely to be at risk of pollution by spills from the major offshore production areas. Methods used in forecasting movement of spills are discussed.
Drilling Highly Deviated Wells in Umm Shaif Field: Problems and Solutions
Authors: Aggour S. B. , Rouatbi R.
Published: December 2007

Three years ago, ADMA-OPCO, started mainly drilling highly deviated wells in Umm Shaif field for development and reservoir reasons. To achieve this objective and to overcome drilling difficulties, more refined techniques have been used, namely: –The use of hole cleaning and stiff 17 1/2″ bottom hole assemblies, in addition to non rotating sleeve stabilizers, which reduces lost time in 17 1/2″ phase.–Turbodrilling using hydraulic stratapax bits to enable setting 9 5/8″ casing in base of Thamama V.–Turbodrilling short section of the 8 1/2″ phase which eliminates the problems in this section and cuts short most of the completion and testing difficulties.

The application of the above techniques has led to ADMA-OPCO successfully drilling highly deviated wells with minimum time and low cost.
An Engineering and Geological Review of the Problems Encountered in Simulating Naturally Fractured Reservoirs
Authors: Waldren D. , Corrigan A. F.
Published: December 2007

The geological origin of factors important for fluid displacement in fractured reservoirs is discussed. A review of mathematical modelling approaches for fractured reservoirs is presented, their limitations discussed and some new techiques are proposed.
Data Gathering Comes Hard!
Authors: Ekola E.C.
Published: December 2007

When El Paso Natural Gas Company first decided to gather some data from two or three outlying points and relay that information to a central location, there did not appear to be any great or insurmountable problems involved. We are still convinced of the veracity of the original conclusion, but we are also now aware of some of the myriads of small problems and able to give the reader a feel for our particular problems and their solutions.

As originally planned, there were some 41 quantities of analog information (15 second pulse duration) to be gathered from the locations of Phoenix, Tucson, and Casa Grande, Arizona. (See Figure 1). These quantities were to be relayed to a central Despatching location in El Paso, Texas. So far, how they were to be relayed, was open to good engineering practice, economics, and growth requirements.

ANALOG TELEMETER

The most straight forward method would be to relay the signals, or quantities, as they were, in analog form to the El Paso Dispatcher. Assuming that the Dispatcher could live with a time shared reading, three quantities could be displayed on a single recorder in the El Paso office. This would also necessitate 14 leased lines between El Paso and the outlying points. This requirement did not seem to fulfill our need of economics or future growth, to say nothing of good engineering. Just the array of recorders would eventually outgrow the wall space available.

USE OF INFORMATION

At this point it would be well to digress a moment and outline the use to which these particular readings will be used in order to clarify the following points.

The information to be gathered is natural gas pipeline static pressures and differential pressures obtained across orifice plate meters. The information is used to calculate instantaneous flow rates, accumulate gas volumes, figure line packs, to monitor pipeline conditions and to note trends.

The information was previously recorded on circular charts at the outlying locations and periodically the required information was phoned or teletyped to the Dispatcher in El Paso. The Dispatcher at the outlying point calculated all of the volumes and merely transmitted the end result.
A High-Rate Gas Lift Test in Saudi Arabia
Authors: Camp G. F.
Published: December 2007

Accurate vertical multiphase flow correlations and detailed knowledge of gas lift valve operating characteristics are essential to the design of more economic gas lift systems. Available information on these subjects is not reliable for high velocity flow conditions. This paper describes tests performed in Saudi Arabia to obtain this information and the application of test results.
Calculating In-Place and Recoverable Hydrocarbons: A Comparison of Alternative Methods
Authors: Smith P. J. , Buckee J. W.
Published: December 2007

An important component in the assessment of the economic risk of a prospect prior to development is the calculation of in-place and recoverable reserves and their associated uncertainty. This calculation requires the multiplication of the probability distributions of volume, porosity, net-pay to gross etc. to form the probability distribution of reserves. Two methods have been advocated for this calculation;

Parametric methods and Monte-Carlo methods

In (i) component distributions are combined analytically to give measures of average and confidence levels in reserves. whereas in (ii) the distribution of the components are randomly sampled to build-up the distribution of reserves. Although at present the Monte-Carlo approach has been widely advocated in the petroleum industry, due to their general applicability, the parametric methods have many adherents citing their ease and speed of use as principle reasons. However, there is a seeming lack of rigorous analysis in either method which would make the selection of the most appropriate method for a particular problem more objective. In this paper we address this area and show how the errors in both methods can. be reduced. Additionally, we suggest a new approach which combines the strengths of both methods into a flexible algorithm for reserves calculations.
In-Situ Stress State in the Mounds Test Well as Determined by the Anelastic Strain Recovery Method
Authors: Teufel L. W.
Published: December 2007

A method to determine in situ stress directions and magnitudes from anelastic strain recovery measurements of oriented core has been used to determine the principal horizontal in situ stresses in the mounds test well near Tulsa, Oklahoma. The mounds experiment was a shallow field experiment designed to evaluate and compare various methods of determining hydraulic fracture azimuth and geometry at depth. The azimuth and geometry of hydraulic fractures are controlled primarily by the orientation and magnitudes of the principal in situ stresses. In the mounds experiment the principal horizontal stress directions were determined directly from the principal horizontal strain recovery directions of oriented core. The principal horizontal stress magnitudes were calculated from the principal strain recovery magnitudes, effective overburden stress, and mechanical properties of the rock using a viscoelastic model. The in situ stress directions and hydraulic fracture azimuth determined from anelastic strain recovery measurements were within 10° of the fracture azimuth determined from a downhole television camera and a surface tiltmeter survey of a propagating hydraulic fracture. The minimum horizontal stress magnitude determined by the strain recovery method was within 2 MPa of an open-hole hydraulic fracture stress measurement.
Some Characteristic Properties Of Colorado Oil Shale Which May Influence In Situ Processing
Authors: Allred V. Dean
Published: December 2007

Introduction

There are excellent reasons for trying to develop practical in situ techniques for processing oil shales. In conventional processing, as high as 80 percent of the material mined must also be disposed of as the inert inorganic portion of oil shale. This presents a costly materials handling problem. In addition, as much as 25 percent of the oil shale in place will be left behind as pillars in the mines. Another important consideration is that the rich, thick shale deposits are found under considerable overburden and not readily amenable to mining. There are unique problems and requirements that restrict the use of known in situ processes to oil shales. Among these considerations are such facts as: a. Oil shale does not contain oil, a- such, but is a marlstone of finely divided particles consolidated into rock with a solid insoluble organic matter called "kerogen."b. The only known technique for forming and liberating oily matter from shale is by first heating it until the solid organic matter decomposes into oil, gas, and a solid carbonaceous residue.c. Oil shale deposits in their natural state have little orno initial permeability to gases and liquids. The major problem is the lack of permeability and porosity. However, it should also be kept in mind that oil matter, as such, does not exist in shale.
Great Canadian Oil Sands Project
Authors: Moss A.E.
Published: December 2007

One of the world's largest known reserves of petroleum is contained in the extensive bitumen-bearing sand deposits located in the Province of Alberta, Canada.

More than 175 years ago, one of the early explorers of Canada's Northwest recorded his observation of a black, sticky tar-like substance in the bedded sand banks of the Athabasca River. This material was used by Indians of the area for patching canoes and for other purposes where a water-proofing substance was required. The economic potential of these sands was recognized by geologists of the Geological Survey of Canada more than 75 years ago, even though the vastness of the reserves was not confirmed by core drilling until the 1940's.

The estimated reserves of recoverable oil contained in the tar sands of Northern Alberta are in excess of 300 billion barrels. The area underlain by these sands is at least 13,000 square miles, which is equivalent to approximately one-twentieth of the area of the Province of Alberta. Nearly 90 per cent of the reserves occur in an irregular area some 150 miles long and 50 miles wide known as the Athabasca Tar Sands deposit.

It is not the purpose of this paper to discuss in detail the many reasons why these deposits were not exploited at an earlier date. Suffice it to state that, in addition to two world wars, a major economic depression and the lack of available markets, there were a great many technological difficulties to solve. During the past several decades, many tens of millions of dollars have been spent on investigations by the Federal and Provincial governments, oil companies and other private investigators on drilling, sampling and research, including pilot plant tests, in an effort to determine an economic method of extraction.

Knowledge of the Alberta tar sands deposits has been accumulating rapidly in the past two decades. In this paper, I will describe the geology and characteristics of the tar sands, and the mining and processing project of Great Canadian Oil Sands Limited.
Wireline Operations in the Deep Delaware Basin
Authors: Cunningham J.D. , Fulkerson F.D. , Gollwitzer L.H.
Published: December 2007

Deep wells in the Delaware Basin, just as in other areas, complicate wireline operations. As compared with shallow well operations, increased depths, temperatures, and pressures place greater demands on equipment and operating techniques.

Temperature, although high in the deeper Basin wells, is less a problem than in other regions of large geothermal gradient. All modern logging equipment is designed and maintained to perform properly at temperatures as high as 340°F. Some instruments, such as the Gamma-Ray Neutron, operate at temperatures up to 500°F. Perforating, formerly a problem in high temperature wells, is now accomplished at temperatures up to 470°F through the use of special high temperature shaped charge components. Thus, although temperatures in deep Basin wells require careful preparation, they do not preclude effective logging and perforating operations.

Relatively light muds are used in the Delaware Basin to increase the efficiency of drilling operations. These low density muds create problems that are more or less unique to this area. First, all operations, both logging and perforating, are normally run using blowout preventers. A properly installed pressure control system enables efficient and safe logging operations. Second, the relatively light muds for such deep wells lead to high cable tension during wireline operations. Winch drums and cables must be engineered to operate safely under these unusually high tensions. A special powered sheave wheel has been introduced in the Delaware Basin to reduce cable tension at the drum and to further reduce possibilities of winch drum collapse, or of cable "cutting in" to lower layers on the drum.

Introduction

Deep wells in the Delaware Basin are not the easiest wells to log and perforate. In addition to the usual complications at extreme depths - such as elevated temperatures and pressures, and greater margin for error in depth measurements - these wells offer special problems.
Rock Failure Due to Applied Hydraulic Forces
Authors: Sheffield John S.
Published: December 2007

Introduction

The purpose of this paper is to investigate rock failure by applied hydraulic forces. This investigation will be approached through a review of basic rock mechanics concepts.

Rock mechanics is the one most important physical consideration from the time a well is spudded until abandonment. Rock mechanics is defined as the area of knowledge which deals with how rocks that comprise the outer part of the earth's crust behave and respond to applied forces. We are interested in three basic modes of rock behavior - failure, failure prevention, and yielding.

Discussion

Rock behavior influences several phases of well life including drilling, completing, and operating. Specifically it influencesformation drillability,lost returns,hole sloughing,hole closure,abnormal pressure,perforating,fracturing,additional recovery injection pressures and pattern efficiency, andsqueeze cementing.

This paper will be limited to rock behavior and response due to applied hydraulic forces. Other important man-induced forces that affect rock behavior are mechanical, such as the drill bit, packer, and fracture proppant, and explosive forces, which include the conventional jet perforating charge, proposed jet drilling charge, and the proposed atomic fracturing charge.

Before we can determine rock behavior due to applied forces, we need to briefly consider in-situ forces and rock properties.

In-Situ Rock Stresses

Materials that make up the earth's crust can behave as an elastic, plastic, or elastic-plastic material depending upon material nature, applied force, and temperature. Materials that have a tendency to behave plastically at low stress levels (depths less than 20,000 feet) are shale and salt and among the materials that normally behave elastically are sandstone and limestone.

Normally, when we study a material, we like to consider it homogeneous and isotropic. The rock that we are concerned with is porous and laminated; therefore, rigorously speaking, the rock in question is neither homogeneous or isotropic since homogeneous and porous are contradictory adjectives and likewise isotropic and laminated are opposites. However, initially in our stress analysis, we will consider the rock to be an elastic, homogeneous, isotropic, porous material.
A New Concept In Offshore Drilling Rig Power Distribution
Authors: Andrus J.L. , Lewis Ronald L. , Anderson Hugh B.
Published: December 2007

Publication Rights Reserved

This paper is to be presented at the Symposium on Offshore Technology and Operations of the Society of Petroleum Engineers of AIME in New Orleans, La., on May 23–24, 1966, and is considered the property of the Society of Petroleum Engineers. Permission to publish is hereby restricted to an abstract of not more than 3000 words, with no illustrations, unless the paper is specifically released to the press by the Editor of the Journal of Petroleum Technology or the Executive Secretary. Such abstract should contain conspicuous acknowledgment of where and by whom the paper is presented. Publication elsewhere after publication in the Journal of Petroleum Technology or Society of Petroleum Engineers Journal is granted on request, providing proper credit is given that publication and the original presentation of the paper.

Discussion of this paper is invited. Three copies of any discussion should be sent to the Society of Petroleum Engineers office. Such discussion may be presented at the above meeting and considered for publication in one of the two SPE magazines with the paper.

A new system of offshore drilling rig power generation and distribution is presented that utilizes gas turbines as prime movers turning alternating current generators paralleled on a single power buss to furnish all rig power. All major drilling components are driven by totally enclosed fan-cooled motors with fluid coupling transmission assemblies utilized to provide speed control. An engineering evaluation and a cost comparison of the AC-turbine system is made with the conventional diesel electric system.

Introduction

The gas turbine recently made its debut, as prime mover, on a land drilling rig. As the turbine rig spudded in, a paramount milestone was achieved in drilling rig power generating and distribution. The compact design, low maintenance, and high dependability of the turbine provide the key to the design of the high performance offshore drilling rigs of tomorrow. The nature of the turbine lends itself to AC(alternating current) power generation bringing a new perspective to rig power distribution.
Tow Tank Test of a Current Velocity Profiler
Authors: Abbott C. E.
Published: December 2007

To measure current speed and direction in a vertical comumn of the ocean, an automatic profiling device has been outfitted with speed sensors to collect data while it automatically glides up and down a remote morring wire. To measure the accuracy of the system, a complete vehicle was first towed in a large fresh-water tank at various speeds and angles of attack. Two speed sensor types, rotor and electromagnetic, were evaluated and the results are presented in this report.
Bridging Effectiveness of Perlite for Light Weight Cements and Lost Circulation
Authors: Hall Don
Published: December 2007

The need for light weight cementing aggregate for use in oil well cementing is reviewed and results are presented from laboratory and field tests or perlite-cement slurries. The slurries may be obtained from either high early strength or normal Portland cements by the addition of perlite and bentonitic clay to control the weight and setting of the slurry. Substitution of perlite cement for conventional slow-setting cements may give better completion results because the perlite cementing composition has lower setting strength, lower slurry density and greater slurry stability than conventional cement slurries. With the high bridging effectiveness of perlite-cement containing a percentage of bentonite, it is possible to place longer columns of cement slurries and reduce the possibility of having uncemented sections caused by the settling of cement particles before the cement sets. The perlite cement slurries have resulted in increased penetration while perforating casings without resultant loss of adhesive properties to the casing and formation, and in elimination of shattering of the perlite cement.

Perlite having a proper particle size distribution, when added to a drilling mud stream in proper proportions, effectively combats and prevents many types of lost circulation. Because perlite is of volcanic glass origin, it is chemically inert. Therefore, its presence in the drilling mud does not change the chemical properties of the mud.

Introduction

In the past many wells were completed by the open-hole method and the high strength of cement was of paramount importance. As a result of modern technology, many oil wells are now completed by the setting of casing through the productive horizons and completed by selective perforations.
Oxygen Stripping for Water Flood Corrosion Control
Authors: Finley H.F.
Published: December 2007

The corrosiveness of Lake Maracaibo water can be greatly reduced by removing its dissolved oxygen. A packed deaeration tower for this purpose was built and operated as a part of the Santa Barbara Pilot Water Flood project. The oxygen is stripped with natural gas containing carbon dioxide. Carbon dioxide is absorbed in the process. As the carbon dioxide content of the water increases the pH decreases. Experimentally determined equations are given to show the relations between oxygen, carbon dioxide, and pH at various water throughputs and gas-water ratios.

Corrosion rates were determined on both the inlet and outlet sides of the tower. Flanged spools gave average corrosion rates over the time of the test period. Corrosometer probes were placed in different size pipe to determine the effect of water velocity.

The corrosion rates on the outlet side of the tower were only 10 to 15 percent of those on the inlet side. The outlet piping was clean whereas-the inlet piping was heavily scaled with corrosion products. Data are given to show the variation of corrosion rate with dissolved oxygen, carbon dioxide, and pH. The effect or water velocity is discussed.

It is concluded that a deaeration tower is a practical means of reducing the corrosiveness of Lake Maracaibo water.

Introduction

Water flooding has long been recognized as a profitable means of increasing petroleum production. The payout can be especially attractive i those areas such as Lake Maracaibo where there is an abundant supply of water. The reservoirs in this area are large enough to take large volumes of water over long periods of time. This increases return on investment since construction and operating costs per barrel injected are less than for low volume - shortlife floods.

A factor that can markedly reduce the investment return on a long life flood is the expense due to equipment corrosion. The allowable corrosion rates in a 20 year flood are one half those of a 10 year flood. The nature or corrosion is such that the frequency of corrosion failures reaches a maximum in the later life of a flood near its economic limit. Repairs and replacements that would be economically feasible in the first 5 years of a 20-year flood become prohibitive in the last 5 years.
Approaches for Developing and Utilizing New Technologies in the Petroleum Industry
Authors: Porter W. A.
Published: December 2007

In order to discuss approaches for developing and utilizing new technologies in the petroleum industry, I thought it important to review, at least in part, how the petroleum industry has done it in the past. I must admit up-front to you that my personal sense, coming from the microelectronics field, was that the petroleum industry is less than noted for dramatic or aggressive technological revolution. I was incorrect. My research for this paper has revealed some interesting facts about new technologies and the approaches or circumstances which led to them.

Before focusing on what I believe to be an important, and possibly new, approach for developing and applying new technologies for the petroleum industry, I would like to share some important past examples.

Probably the best example of a successful technology in widespread oil recovery use today is fluid injection or water flooding. This common recovery method has resulted in more barrels of reserves for the United States than any other recovery method. Not surprisingly, it was discovered by accident due to a leak in a makeshift packer in the 1880's. It was illegal in most states until the 1920's and today high-pressure sea water, air and gas systems are in use.
Log Analysis Problems and Solutions in Complex Lithology Reservoirs
Authors: Ruhovets N. , Oliver D. W.
Published: December 2007

Advanced analytical methods and formulas have been developed for two- and three-mineral solutions in complex lithology reservoirs. Required logs are density, neutron, acoustic and photoelectric absorption index (PE curve). On the basis of developed mathematical models of complex reservoirs the limitations and maximum possible errors in the determination of porosities and lithological compositions are presented for each method.
Summary of Geologic Framework and Petroleum Potential of the Atlantic Coast
Authors: Maher John C.
Published: December 2007

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The Atlantic Coastal Plain and Continental Shelf of North America is represented by a belt of Mesozoic and Cenozoic rocks, 150 to 300 miles wide and 2,400 miles long, extending from southern Florida to the Grand Banks of Newfoundland (fig. 1). This belt encompasses an area of about 400,000 to 450,000square miles, more than three-fourths of which is covered to depths of 600 feet by the Atlantic Ocean. The volume of Mesozoic and Cenozoic rocks beneath the Atlantic Coastal Plain and Continental Shelf exceeds 450,000cubic miles, perhaps by a considerable amount. More than one-half of this is seaward far enough to contain marine source rocks in sufficient proportion to attract exploration for oil. A larger fraction, perhaps three-quarters of the volume, may be of interest in exploration for gas. The Coastal Plain consists of an area of more than 100,000 square miles between the crystalline piedmont of the Appalachian System and mean low-tide from southern Florida to the tip of Long Island plus a few small offshore islands and the Cape Cod Peninsula. The Continental Shelf extends from mean low-tide to the break marking the beginning of the continental rise, which is somewhat less than 600 feet in depth at most places. It is a gently sloping platform, about 350,000 square miles in area, that widens from less than 3 miles off southern Florida to about 285 miles off Newfoundland. The Blake Plateau occupies an area of about 70,000 square miles between the 500-foot and 5,000-foot bottom contours from the Cape Hatteras vicinity to the northernmost bank of the Bahamas. It has a gentle slope with only minor irregularities and scattered patches of Recent sediments. Both gravity and magnetic anomalies along the Atlantic Coast reflect primarily compositional differences at considerable depths in the earth's crust, but are related to some extent to the structure and composition of the Coastal Plain sedimentary rocks and shallow basement. Four alternating belts of predominantly positive and predominantly negative Bouguer gravity anomalies extend diagonally across the region from southwest to northeast (as shown on the Bouguer Anomaly Map of the United States, U. S. Geol. Survey, 1964). These correspond roughly with the continental rise and slope, the Continental Shelf and Coastal Plain, the Appalachian Mountain System front, and the Piedmont Plateau-Blue Ridge-Appalachian Basin region.
Cement Bond Log: Determining Waiting-on-Cement Time
Authors: Jordan M. E. , Shepherd R. A.
Published: December 2007

A procedure for determining the minimum waiting-on-cement time before running a cement bond log has been developed to minimize idle drilling rig time prior to performing completion operations. The method accounts for both the set properties of cement slurries and the cement bond log tool response function. Using this method, valid cement bond logs have been obtained after waiting-on-cement times of less than 24 hours.
Field Use of Halogen Compounds To Trace Injected CO2
Authors: Craig F. F.
Published: December 2007

The source of carbon dioxide (CO2) breakthrough is masked for production wells in the interior of a CO2 miscible flood. An inexpensive, safe, and continuous tracer is desirable to monitor the flood performance.*

Halogen compounds (specifically halocarbon-11, halocarbon-12 and sulfur hexafluoride) have been used successfully to identify the source of produced carbon dioxide in a field-wide miscible flood project.