bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of Highly Deviated Wells with Gamma Ray/Electric Logs and Cased Hole Density/Neutron Logs
Authors: Haley R.A. , Kirchoff D.L. 
Published: December 2007

American Institute of Mining, Metallurgical, and Petroleum Engineers, Inc.
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, with the paper, may be considered for publication in one of the two SPE magazines.

Abstract
SARABAND computer analysis using the gamma-ray and induction logs in open hole with the compensated neutron log (CNL) and the formation density log (FDC) in cased hole provides an alternate method for evaluating provides an alternate method for evaluating highly deviated offshore wells in the Gulf of Mexico.

Introduction
The number of highly deviated holes being drilled in the Gulf of Mexico is increasing rapidly. Often the hole conditions can become so severe that unorthodox logging methods, consuming large amounts of expensive rig time, are required to complete a minimum logging program. The use of open-hole gamma program. The use of open-hole gamma ray-induction resistivity log (GR-ISF) and the compensated neutron-formation density logs (CNL-FDC) made in casing as input to a SARABAND analysis is proposed in this paper as an effective solution to some of these problems. problems. Often in development drilling, enough geologic data is available to justify setting pipe after running only an electric log in open pipe after running only an electric log in open hole. This practice, however, usually leaves hydrocarbon type and volume undetermined in many zones. In order to define the accuracy with which these quantities can be determined in casing with a combination density-neutron (CNL-FDC) tool, 17 zones in a well with good open-hole data were logged in casing and systematically analyzed. The results show that in many cases this method of well evaluation will be a workable alternative to using conventional or even some newly developed open-hole techniques.
A full suite of open-hole log data, if available, remains superior to this approach. However, often conventional porosity and sidewall core tools simply will not reach the objective section in very high angle holes. Also, the advantages of obtaining open-hole porosity data are partially or completely offset porosity data are partially or completely offset by the additional rig time costs and increased risk of losing the hole.

OPEN VS CASED-HOLE DENSITY LOG
Attempts have been made to estimate formation density from cased-hole density logs. In the subject zones, the bit size was 9-7/8 in. and 39 lb — 7-5/8-in. casing was set.
Cluster - A Method For Selecting The Most Probable Dip Results From Dipmeter Surveys
Authors: Hepp V. , Dumestre A.C. 
Published: December 2007

American Institute of Mining, Metallurgical, and Petroleum Engineers, Inc.
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, with the paper, may be considered for publication in one of the two SPE magazines.

Abstract
The several curve displacements determined from four-arm Dipmeter surveys can be combined in many ways to obtain formation dip, When the different displacement combinations at a given level do not lead to the same dip value, use can be made of the redundant data from the level, along with data from overlapping adjacent levels, to determine the most probable dip. CLUSTER is a technique for doing this.
Fluid Frictional Diversion Technique for Sequential Multistage Horizontal Stimulation
Authors: Grieser Bill , Wiemers Tim , Hill Britt 
Published: December 2007

Abstract
This paper describes a method for fracture-stimulating noncemented horizontal wells in multiple stages. For existing openhole horizontal wells, an open-ended nonperforated liner is inserted nearly to the toe of the horizontal section. The liner is hung off inside intermediate casing, and the liner top is packed off. The liner is not cemented in place. The first fracture-treatment stage is pumped through the liner and out its end, creating a fracture near the toe of the horizontal section. Perforating guns are then positioned downhole to create holes in the liner at the next fracture initiation site. After perforation, the gun is removed, and the next fracturing stage is pumped at a high rate. This process is repeated for each treatment stage, spacing fractures along the horizontal interval.
Treatment diversion is accomplished with high injection rates and a fluid-friction pressure drop. The horizontal distance between fracturing stages is carefully designed for optimizing all diversion parameters and maximizing the effects of fluid friction in diverting fluid into each new perforation set. No special liner equipment, mechanical diversion equipment, or packers are used.
For an existing openhole horizontal completion, the design is based on the liner size, the diameter and number of perforations, the distance between perforations, and the injection rate required to achieve diversion. This technique is most effective when the hole size, pipe size, and horizontal length are in a specific range.
A circuit analogy of a parallel electrical circuit with multiple resistors graphically demonstrates the calculation of individual injection rates and treatment volumes required to divert the inj ection fluid through the various flowpaths into multiple sets of perforations.
In one field case, a high-volume fracture-stimulation treatment was pumped down intermediate casing into an open horizontal hole at a high rate. The post-fracture production was less than expected. Later, a solid liner was inserted into the open hole, and the operator used the frictional diversion technique (FDT) to distribute fractures at selected sites along the horizontal section. An incremental production increase, a lower decline rate, and increased reserves were obtained.
Improving Reservoir Performance of the Painter Reservoir Unit
Authors: Ring J. N. , Heffner T. A. , Elliott M. W. , Zack J. G. 
Published: December 2007

Abstract
A rigorous evaluation of Painter and East Painter Reservoir fields produced extraordinary results, both economically and technically. The evaluation's goal was to identify remaining hydrocarbon potential, if any, and to reduce operating expense. The results of the evaluation have initiated and sustained a highly successful horizontal drilling program, increased reserves by extending full pressure maintenance (with nitrogen injection) by several years, and substantially improving current financial performance.
Painter and East Painter Reservoir fields, located in Uinta County, WY, are collectively known as the Painter Unit, because both fields produce from the Nugget formation and are tightly integrated through common facilities. In 1995, the Painter field was rapidly approaching its economic limit after producing only 25% of the OOIP, and immediate blowdown (cessation of full pressure maintenance) seemed inevitable, which would result in reserve losses from both fields because of nitrogen (N2)) supply considerations. This paper will focus on the technical methodology used to improve the performance of these reservoirs, and will share some of the financial results.
Evaluation of Centrifugal Drying for Recovery of Synthetic-Based Drilling Fluids
Authors: Bradford D. W. , Growcock F. B. , Malachosky E. , Fleming C. N. 
Published: December 2007

Abstract
Loss of synthetic-based mud (SBM) on drilled cuttings discharged offshore can add considerably to the drilling fluid cost. In addition, offshore environmental regulations are becoming increasingly strict, causing discharge of SBM to be severely curtailed. To reduce the loss and discharge of SBM, a new mud recovery technology – Centrifugal Drying – was tested as an enhancement to conventional solids control technology on four development wells in the Gulf of Mexico.
Centrifugal Dryers, sometimes called rotating shakers, remove fluid from the cuttings by use of a spinning, screened basket arrangement which imparts a Centrifugal force on the order of 100 G on the cuttings. Cuttings discharged from the shakers are transferred to the Dryer's inlet pipe and are fed by gravity to the distribution cone and support disc. The cone removes the cuttings from the pipe and accelerates and spreads them evenly over the inner surface of the conical screen. Cuttings are held to the screen by Centrifugal force and moved to the exit port via vibratory motion or a sweeper, while the drilling fluid is forced through the screen and recovered.
In the field tests, the conventional solids control equipment left a residue of synthetic fluid on the cuttings (SOC) of 10 to 15% by weight, whereas the Centrifugal Dryer was generally found to reduce SOC to less than 5% by weight (Fig. 1). Furthermore, the cuttings discharged from the unit dispersed readily and produced no visible sheen when released into the sea water under the cuttings discharge line. By reducing the volume of synthetic discharged, a savings of about $100,000 in mud cost was realized over the life of the project (4 wells).
A Novel Technique for Single-Selective Sand Control Completions Allows Perforating and Gravel Packing of Two Zones with Zonal Isolation in One Trip: A Case History from Trinidad
Authors: Waters F. , Singh P. , Baker C. , van Wulfften Palthe P. , Parlar M. 
Published: December 2007

Abstract
Single-selective gravel pack completions with zonal isolation can be very expensive particularly in offshore environment where rig costs are high. Conventionally, such completions involve perforating and gravel packing of each zone separately, with multiple trips in and out of the hole. A typical procedure consists of the following 6 round-trips excluding a wire-line trip to set the sump packer and running in hole with the production tubing: (1) Perforating the lower zone, (2) Gravel packing the lower zone, (3) Running and setting the packer plug to isolate the lower zone, (4) Perforating the upper zone, (5) Retrieving the packer plug, (6) Gravel packing the upper zone, with a GP assembly that includes an isolation assembly for lower zone. The first two trips can be combined into one trip by using a single trip perforating and gravel packing system, reducing the number of round trips to 5. In addition, fluid loss control pills are quite often required after perforating.
In this paper, we present a new technique for single selective sand control completions in cased holes that allows perforating and gravel packing of both zones with a zonal isolation device between the zones bypassed through shunt tubes for gravel packing the bottom zone. This procedure reduces the number of round-trips from 6 (compared to conventional) or 5 (compared to single trip option for the lower zone) to 1, saving a minimum of 4 round-trips, in addition to eliminating fluid loss control pills throughout the whole operation. This technique has recently been used in an BP-Amoco well in Trinidad where the lower zone is expected to water out sooner than the upper zone and the production is commingled. This application resulted in 17% savings to BP- Amoco in completion costs, in addition to an increase in production from 800 bopd to 1,200 bopd. Details of the tool modifications and the field application (design, execution and evaluation) are discussed along with an economic comparison to earlier practices.
A Sampling of Variational Methods
Authors: Rachford H.H. 
Published: December 2007

American Institute of Mining, Metallurgical, and Petroleum Engineers, Inc.
THIS PAPER IS SUBJECT TO CORRECTION

Introduction
As an introduction to a session on variational methods in reservoir modeling, the purpose of this paper is to emphasize the rich variety inherent in the structuring of such methods. We illustrate this with a few examples, chosen partly to suggest that there may remain more such methods yet to be discovered and tried than methods already known and tested. This paper is not intended to be a survey, nor is it intended to present a full account even of the ideas illustrated. Indeed, a complete compendium of known variational methods potentially applicable to reservoir simulation and all the details of the methods discussed would be needlessly lengthy and distract from our main purpose: inspiring the imagination of the reader to the exciting potential of that which may yet come.
The variety of variational methods can best be illustrated by showing examples of a number of ways to treat the same problem. For this it is helpful to choose a simple system which retains the character of reservoir simulation problems. For this we consider the equations on a bounded region Rn for 0 t T
(1)
(2)
where a and are strictly positive smooth functions, Q(x,t) is flow data, = u if Q 0, and (x,t) is data for Q greater than 0.
Revitalizing An Aging Field - Tinggi Production Decline Mitigation
Authors: Kabir A. H. , Othman M. , Talib M. , Hitam S. , Janor M. , Osman A. , Yunos A. 
Published: December 2007

Abstract
Abnormal production decline causes concerns like high operating cost, premature field abandonment resulting in reserves loss and staff demoralisation, all of which have an adverse effect on an E&P company. Operational problems like high sand & emulsion, high scale deposition in the production system adds to the normal challenges of an aging field, making decline analysis more complicated where actual reservoir production decline gets masked by non-reservoir factors. Overcoming all these operational challenges as well as natural production decline calls for innovative thinking and a holistic approach, especially because all the interrelated problems need to be addressed simultaneously and that too sometimes with insufficient data. Reservoir productivity, tubing and surface facilities performances must be optimised as an integrated system. Otherwise, isolated efforts at various parts of the production system are bound to give poor results.
In this paper we describe a case history of an integrated production optimisation effort undertaken on Tinggi field in offshore Terengganu, Malaysia. The field suffers from operational problems like sand, emulsion and scale resulting in widespread equipment malfunction, measurement problems, erosion of valves, chokes, orifices etc. Production declined sharply at a rate of about 26% per year over 1994 to 1997. In early 1998 it was producing 5.8 MSTB/d of oil with a water cut of about 90%. A multidisciplinary team was then formed in order to mitigate this sharp decline which threatened the viability of the field's operations. The team took an innovative approach in coming up with practical and cost effective solutions by studying all the problems and their correlation. All the key operations personnel were interviewed in order to gather information vital to diagnose all the problems systematically. Despite lack of sufficient good quality data (caused by operational problems) the team came up with solutions, implementation of which were gradual and phased, in order to minimize risk in the face of many uncertainties. Production started picking up immediately and the field's current production is 9.5 MSTB/d (in June 1999) with further production gain yet to be realized through additional perforations campaign targeted in October 1999. Most of the earlier solutions were implemented at minimal additional cost. The company plans to extend the result of this study to other fields in a more proactive manner.
Semi-Direct Iterative Methods in Numerical Reservoir Simulation
Authors: Letkman J.P. 
Published: December 2007

American Institute of Mining, Metallurgical, and Petroleum Engineers, Inc.

Abstract
In the past efforts in reservoir simulation have been directed to efficient techniques for solving the set of simultaneous equations arising in multi-phase multi-dimensional fluid flow. Techniques which have been investigated have included both direct solution and iterative methods such as SOR, ADIP and SIP. Iterative techniques have received greater attention since direct methods usually require significantly more computer storage and computing time. Direct methods have been the only alternative for problems which are insolvable with iterative methods, and the direct solution approach becomes competitive for those problems which are slow to converge. problems which are slow to converge. A semi-direct iterative approach is described which extends the capability of iterative methods to solve the more complex problems which result from severe heterogeneities due to geometries or reservoir properties. The semi-direct methods investigated in this paper determines the advantages of including additional diagonals in the triangular decomposition matrices. If all diagonals are included in the triangular matrices the semi-direct method becomes equivalent to the direct method. The investigation showed the asymptotic convergence rate on a computational work required basis was approximately equal to SIP for the model problem proposed by Stone. It achieved faster convergence for the heterogeneous model problem. For some complex problems the method will obtain convergence where SIP fails to converge or converges slowly.

Introduction
Finite difference approximations to the parabolic and elliptic partial differential equations usually lead to a system of simultaneous equations. These equations may be solved directly by elimination methods or by iterative methods such as relaxation, successive over-relaxation, alternating direction iteration or the strongly implicit procedure. procedure. The direct method is efficient for small problems but computer time requirements become excessive for multidimensional problems involving several thousand mesh points. The direct method requires computational effort of the order of IJ for IJ equations in two dimensions and of the order IJ K computations in three dimensions.
A Comparative Evaluation of Different Versions Of the Strongly Implicit Procedure (SIP)
Authors: Suarez A. , Ali S.M. Farouq 
Published: December 2007

American Institute of Mining, Metallurgical, and Petroleum Engineers, Inc.

Abstract
The well-known Strongly Implicit Procedure (SIP), introduced by Weinstein, Stone, and Kwan, was tested for two- and three-dimensional, two-phase reservoir flow problems. Additionally, it was evaluated for the two-dimensional Laplace's equation, where the exact solution was known.
The evaluation consisted in the comparison of the convergence behavior of the SIP algorithm where a single set of equations is used for all iterations, with the algorithm employing two sets of equations, one for odd-numbered iterations, and the other for even-numbered iterations. Also, the effect of the number and ordering of the iteration parameters on convergence was investigated. The algorithm for odd numbered iterations has already been reported by Weinstein et al. The algorithm for even numbered iterations was derived, and is given in this paper.
It was found that less than 10% additional computational effort was expended when using the odd-even iterations algorithm as compared to the original odd-numbered iterations algorithm. However, the odd-even iterations algorithm permitted a significant improvement in the permitted a significant improvement in the results: the material balance errors decreased, and the residuals were lower. The residuals decreased by several orders of magnitude when the convergence tolerance was tightened.
For both versions of SIP, the number and ordering of the iteration parameters was found to have a profound effect on the convergence behavior. Any significant trend was not apparent, however.
It is recommended that the odd-even iterations version of SIP should be used for reservoir problems, and that trial runs should be carried out to determine the optimum number of parameters and the best (e.g. increasing, parameters and the best (e.g. increasing, decreasing, etc.) ordering of the same. The paper discusses these factors for the reservoir paper discusses these factors for the reservoir problems tested. problems tested

Introduction
The Strongly Implicit Procedure (herein-after referred to as SIP) is a highly successful algorithm for the iterative solution of systems of linear equations arising from the application of implicit differences to reservoir flow problems. The advantages of SIP over Alternating problems. The advantages of SIP over Alternating Direction Implicit (hereinafter referred to as ADI) and Successive Overrelaxation (hereinafter referred to as SOR) procedures have been discussed in the literature.
A Steam-Soak Well Model for an Isothermal Reservoir Simulator
Authors: Williamson A.S. , Drake L.P. , Chappelear J.E. 
Published: December 2007

An isothermal reservoir simulator may be used to investigate the field-wide application of the steam-soak process. Thermal effects, which are confined to regions close to the soaked wells, are introduced using a semianalytical procedure for calculating fluid production rates. This takes account of saturation and temperature changes in the vicinity of the soaked wells.
In this paper we describe a semianalytical model of the steam-soak process (a steam-soak well model) that extends the use of a conventional isothermal reservoir simulator to cover steam-soak operations. With the availability of satisfactory thermal reservoir simulators, the need for a steam-soak well mode perhaps requires some explanation. Using perhaps requires some explanation. Using current computational facilities, the number of steam-soaked wells that can be included in a thermal simulation is severely limited. The impact of soaking operations on the general reservoir performance (e.g., reservoir pressure changes, oil migration from nonsoaked areas) is therefore not easily ascertained. This situation is similar to a water-coning situation. The detailed behavior of one or a few wells where significant water coning occurs may be investigated using a simulator capable of elucidating the fine flow details around a well. However, a field-wide simulation require a different approach, e.g., the use of a coning well model.
A Review of Riserless Drilling Alternatives
Authors: McLeod Wilfred R. 
Published: December 2007

Abstract
The development of mobile offshore drilling rigs has steadily progressed since their inception, but the nature of the development has been more evolutionary than revolutionary. The advent of semisubmersible and dynamically-positioned rigs has had a significant effect on the capabilities of the equipment. However, the drilling systems have been adapted with only slight changes from those used onshore. As drilling progresses into the deeper waters of the continental margins, the use of conventional marine drilling systems will present an increasing number of problems.
One of the basic and most challenging problems in deep water operations is the marine riser, which is used to provide a conduit for well returns, to guide the drill pipe into the hole, and to serve as a support for control cables and choke and kill lines. In deep water, the riser requires supplementary buoyancy to achieve a better stress distribution and reduce the requirements for riser tensioners. This supplementary buoyancy substantially increases the unit cost of a riser joint while, at the same time, more riser is needed. Costs on the order of $1,500/foot or more are not expected to be uncommon for the longer risers.
Many alternatives to the use of the conventional marine riser system for deep-water drilling are already being investigated. These alternatives offer possible means of avoiding big, expensive, hard-to-replace risers and their associated large drilling vessels. Some of the riserless drilling alternatives given in the literature, including patents, are reviewed. An attempt is made to ascertain which alternatives seem to be most promising.