bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fluid Placement Model for Stimulation of Horizontal or Variable Inclination Wells
Authors: Eckerfield L.D. , Zhu D. , Hill A.D. , Thomas R.L. , Robert J.A. , Bartko K. 
Published: December 2007

Abstract
Acidizing is a common method of stimulating horizontal wells. The acidizing process is fundamentally different when applied in a horizontal well compared with application in a vertical well. The fluid distribution in a horizontal well is affected by a longer welibore length. a broader variation in the reservoir properties along the wellbore, and possibly different mechanical means to place the fluids in the wellbore. A comprehensive fluid placement model linked with a reservoir acidizing simulator is essential to precisely design acidizing treatments for horizontal wells.
This paper presents a model of fluid placement in a horizontal well. The model predicts the placement of injected fluids by tracking the interfaces between different fluids in the wellbore. It is capable of tracking multiple interfaces for multiple injection stages in horizontal wells. For injection with coiled tubing, the model allows tubing tail movement during injection. It also handles simultaneous injection from the annulus and from a tubing string. A unique feature of the model is that it considers gravity under-riding of the denser injected acid when the wellbore is not perfectly horizontal. Both analytical and discretized solutions of the model are presented in the paper. Examples in the paper illustrate the effects of such factors as velocity of tubing movement, annular injection, non-uniform distribution of flow into the reservoir, and gravity segregation under-riding in inclined wellbore sections on fluid placement in an acidizing treatment.
The wellbore placement model has been linked with a matrix acidizing model calculating damage dissolution and skin reduction near the wellbore. An example is provided comparing different placement techniques such as bullheading and injection through coiled tubing with and without simultaneous injection through the annulus.
The simulator can help to determine optimum tubing tail locations and optimal injection volumes of acids, to select the most appropriate diverting methods, and, hence, to maximize the benefits of an acidizing treatment.
P. 473
Dehydration of Heavy Crude Oil Using Disc Stack Centrifuges
Authors: Dhuldhoya Nimish , Mileo Mike , Faucher Mark , Sellman Erik 
Published: December 2007

Abstract
Heavy (low API gravity) crude oils are more difficult to dehydrate than light crude oils. Traditional treatment systems for dehydration of heavy crude oil use large separators and large amounts of heat, in combination with the dosing of large quantities of demulsifier chemicals. The traditional treatment systems are bulky and require large structures / deck area for support.
This paper demonstrates that heavy crude oils can effectively be dehydrated (achieve pipeline BS&W specification) using disc stack centrifuges. Due to the compactness of the disc stack centrifuges and the relatively small hold up volumes, the treatment facility can be made more compact and reduce both the required deck space and structural support load on the structure. P. 371
Quantitative Formation Permeability Evaluation from Stoneley Waves
Authors: Brie A. , Endo T. , Johnson D.L. , Pampuri F. 
Published: December 2007

Abstract
Reservoir engineers need a continuous measurement of permeability to optimize well completion and produce the formation effectively. The borehole Stoneley wave has been shown to be sensitive to fluid mobility, the ratio of permeability and viscosity. The phenomenon is well described using the Biot theory, and models to account for the effect of the mudcake have been proposed. Existing techniques use either the Stoneley slowness or its attenuation at low frequency to estimate the fluid mobility with simplified Biot models. However, the results of these techniques usually show unexplained differences from core measured permeabilities, or with well test results. The objective of the methodology presented in this paper is to improve the reliability of the estimation and to take into account important factors that have been neglected.
The evaluation technique described in this paper uses the Stoneley waveforms over a wide frequency range and inverts for fluid mobility applying the full Biot theory. The mudcake is modeled as an elastic membrane. The most important parameters in this evaluation are the mud slowness, mud attenuation, membrane stiffness and pore fluid compressibility. Practical techniques are proposed to obtain these parameters with sufficient accuracy from the recorded data. Stoneley waveform inversion provides a direct and continuous fluid mobility estimate near the wellbore (i.e., in the invaded zone). The intrinsic permeability of the rock can then be derived, provided that the various fluid components, their relative permeabilities and their viscosities are known. Finally the presence of irreducible water in the rock is also discussed as it can affect the estimation of mobility through the reduction of the effective porosity. The application of this methodology to actual data sets is the subject of an accompanying paper.
The Stoneley wave provides a continuous estimation of the formation permeability along the well. Core measurements are not required although they can be used for verification. This technique will find applications in reservoir engineering optimization of well production through better placement of the perforated intervals.
P. 389
A New Method for Remote Sensing of Critical Stratigraphic Bed Boundaries and Reservoir Positioning of Horizontal Wells
Authors: Leggett J.V. , Dubinsky V.S. , Nakken E.I. , Viken R. , Sandvik S.E. , Molz E.B. , Lotsberg O. , Bolshakov A. 
Published: December 2007

Abstract
Stratigraphic features such as fluid contacts, geological markers and reservoir target boundaries are key drilling markers for placing a well. Determining the position of a wellbore relative to these stratigraphic features, at a range to 20 meters, above and below a deviated wellbore, has been a major goal for "Tieing-in" to a reservoir model while drilling. Acquiring, processing raw data, and identifying these features at this range in a measurement while drilling (MWD) tool in real time has not been possible with existing MWD Formation Evaluation and geo-steering systems.
An experimental field prototype tool was run to identify these stratigraphic features. It was run as a pipe conveyed logging operation with wireline and wet-connector inside the pipe for two-way communication. Sonic measurements were also made to provide real time measurement of acoustic velocity/slowness which was used to insure accurate formation velocity. This combined measurement was essential in determining the correct distance to the feature.
This paper presents the proposed configuration of a Sonic While Drilling measurement method of reservoir navigation and lithological boundary identification. The method and benefits of this new type of Acoustic MWD measurement are detailed in this paper.
Stratigraphic positioning and reservoir navigation, formation dip estimation, coring point selection, seismic correlation and high resolution near wellbore reservoir imaging are key applications for this new acoustic measurement method. The field test results demonstrated by this new method indicate that these key applications can be implemented as a new Sonic While Drilling measurement.
P. 413
Advanced Processing Methods for a New Generation Propagation Resistivity Tool Improves Interpretation Methodology
Authors: Hearn F.P. , Meyer W.H. , Wisler M.M. 
Published: December 2007

Abstract
Much more accurate formation evaluation is now made possible by new generation propagation resistivity tools that make more measurements than previous systems. The additional measurements provide new information from the borehole and the near borehole environment as well as the formation itself. They also provide the capability to identify and differentiate between environmental effects.
An new, advanced processing method combines many of the measurements collected by the tool then identifies and corrects for environmental effects. This includes a new method for dielectric constant correction. The method also calculates horizontal (Rh) and vertical resistivity (Rv) for high angle wells where anisotropic effects are present. A global solution for Rh and Rv is derived using a minimum of four measurements. This eliminates uncertainty where multiple solutions of Rh and Rv are possible.
After corrections are made for environmental effects the method then generates four resolution-matched resistivity curves with fixed depths of investigation (radii) at 10", 20", 35", and 60". This format facilitates invasion interpretation, particularly where both resistive and conductive invasion are occurring proximal to one another.
Field comparisons to wireline array resistivity measurements demonstrate the robustness of the method under a variety of formation resistivity environments and clearly shows where interpretation methodology is improved.
P. 431
Pressure Buildup Analysis With Acoustic Data in Beam-Pumped Wells
Authors: Fair Walter B. 
Published: December 2007

Abstract
Pressure buildup analysis in beam-pumped wells has suffered from the difficulty in directly measuring pressures at the bottom of the well. Often the only reasonable method for acquiring pressure data in such wells is to combine casing pressure and acoustic liquid level measurements with estimated fluid densities to indirectly estimate the bottomhole pressure, which is then analyzed. This procedure introduces errors in the bottomhole pressures, thereby degrading the quality of the analysis. It is also difficult to judge the accuracy of the analyses, since the pressures being evaluated are not directly measured.
This paper presents a simple wellbore model that is applicable to pressure buildup tests in beam-pumped wells. When coupled with the normal wellbore and reservoir fluid flow equations, it is possible to directly model the casing pressures and fluid levels that are measured in acoustic surveys. By adjusting the model parameters to directly match the measured data, an improved evaluation is obtained.
Statistical considerations indicate that, since twice as much data is being used, the results should also be more reliable. In addition, however, it has been found that the casing pressure is extremely sensitive to the wellbore effects, particularly phase redistribution. Since an improved description of the wellbore effects are obtained by matching the casing pressure, improved estimates of the skin and reservoir parameters are also obtained.
This paper presents the theoretical and statistical basis for the improved analysis method as well as the mathematical model. In addition, several examples of actual field analyses are shown. Based on the mathematical model, the effect of errors in the data are also estimated and described.
P. 453
In Search of Thickness-Independent Permeability From Transient Pressure-Rate Data
Authors: Kabir C.S. , Joseph J.A. 
Published: December 2007

Abstract
This paper describes a method for estimating formation diffusivity (k/ ct) from the early-time pressure-rate linear relationship. Both radial and spherical flows, often associated with thick formations, are considered in this formulation. Our formulation assumes that the constant-storage wellbore model applies and the rate-time behavior, during both flow and shut- in tests, is well represented by the exponential model.
The proposed method is general in that the type of fluid (oil or gas or oil-water) or mode of flow (production or injection) does not pose any problem. Initially, we verified the method with synthetic examples and then validated it with four field examples.
Validation is shown two ways. In two examples, k values computed by the proposed and conventional methods are compared directly in absence of downhole flow profile. In two other cases, contributing reservoir thickness h was discerned by first estimating the kh product from conventional analyses and then evaluating k using the proposed method. Thereafter, h so obtained by taking the ratio of the two results was compared with the measured flow profiles. Overall, good agreement was achieved in all cases. P. 491
From Seismic to Reservoir Properties Using Geostatistical Inversion
Authors: Lamy P. , Swaby P. A. , Rowbotham P. S. , Dubrule O. , Haas A. 
Published: December 2007

Abstract
Our confidence in a reservoir model is greater if this model is based not only on well logs and geological knowledge, but also on seismic information. The methodology presented in this paper incorporates these disparate data types to produce models of reservoir parameters and uncertainties associated with them. A 3D seismic dataset is inverted within a geological and stratigraphic model using the geostatistical inversion technique. Several reservoir-scale acoustic impedance blocks are obtained. On the one hand, quantification of uncertainty is determined by computing statistics on these 3D blocks. On the other hand, Collocated Cokriging allows the transformation of impedances into reservoir parameters (Vshale in our case) through a petrophysical relationship while respecting information at wells. Finally, these results are transferred from the time to the depth domain for flow simulation.
Microbial Water Treatment: An Alternative Treatment to Manage Sulfate Reducing Bacteria (SRB) Activity, Corrosion, Scale, Oxygen, and Oil Carry-Over at Wilmington Oil Field - Wilmington, CA
Authors: Cassinis Richard B. , Farone William A. , Portwood James H. 
Published: December 2007

Abstract
Injection water is commonly treated with chemical biocides, corrosion and scale inhibitors, and oxygen scavengers, to name a few. Without treatment, iron sulfide, hydrogen sulfide, iron oxide, and other impurities will form, precipitate and damage unprotected surface equipment and lines and plug injection wells. In many cases, acid, xylene and even coiled tubing are required to restore injectivity.
Although traditional chemical treatments can be effective in many cases they are not "worker friendly". This paper will present the results of an ongoing, worker and environmentally safe, lower- cost alternative-Microbial Water Treatment (MWT). A discussion of treatment mechanics, strategies and evaluation are presented along with past and current results of the successful 310,000 barrel per day MWT program at the Wilmington Oil Field.
P. 435
Safety and Environmental Performance Measures in Offshore E & P Operations: Empirical Indicators for Benchmarking
Authors: Iledare Omowumi O. , Pulsipher Allan G. , Mesyazhinov Dmitry V. 
Published: December 2007

Abstract
Several indicators—such as the fire/explosion incident rate, blowout incident rate, oil spill incident rates, production incident rates, and drilling incident rates—have recently been formulated by an industry working group (PMWG) to facilitate the evaluation of environmental and safety performance of OCS operators. In this paper we have attempted to quantify some of these measures using data from an existing Minerals Management Service (MMS) events file for the period 1987-1993. Similar measures such as a relative safety index, nominal accident rate, spill rate, injury rate, fatality rate, and weighted safety score—developed at Louisiana State University's Center for Energy Studies (CES)—are compared to PMWG indicators. Our comparisons of CES performance measures and the PMWG measures, for which data is available, show little difference with respect to the relative performance of small and large independents and majors when considered as groups.
This result strengthens our earlier conclusions that the historical record does not support the concern that the expanded role of independents on the OCS poses any significant danger to safety or the environment in the Gulf of Mexico region.
P. 451
Field Trial of a Multiphase Flow Meter
Authors: Mohamed Peria G. , Al Saif Khaled H. 
Published: December 2007

Abstract
A Multiphase Flowmeter (MPFM) was installed in series with a conventional well testing system (test separators and test tank) at an operating field in Kuwait. The MPFM employs a positive displacement meter, a venturimeter and a microwave sensor to measure the flow of total fluid, gas and water respectively. A bypass loop with a vortex shedding flowmeter enables measurement of a large range of gas flow rate. A number of wells covering a wide range of Production rate (680 to 6130 bpd), Gas Oil Ratio (207 to 889) and water cut (0-65%) were tested. The comparative results are presented. The MPFM results are more accurate, and more consistent than those of conventional system and allows faster well testing. An insight into the behavior of MPFM at varying field conditions and useful information on issues related to range and accuracy are presented. Useful hints to those companies interested in testing/procuring Multiphase Flow meters are also presented.
P. 471
Field Case: Cyclic Gas Recovery for Light Oil-Using Carbon Dioxide/Nitrogen/Natural Gas
Authors: Miller Bernard J. , Hamilton-Smith Terence 
Published: December 2007

Abstract
Cyclic gas recovery ("Huff and Puff") using carbon dioxide has been applied successfully in the Big Sinking Field of eastern Kentucky.
The process was initiated in 1986, and was used continuously until 1994, with 390 treatments on 240 wells. A total of 12,200 tons of liquid carbon dioxide resulted in additional recovery of 180,000 barrels of oil. Successive cycles became less efficient, and a changing market for liquid carbon dioxide resulted in a 50% increase in price. The process was continued with rich gas (1900 Btu casing head) and exhaust gas (80% nitrogen and 20% carbon dioxide).
Both gases were tested in two separate areas of the field where cyclic carbon dioxide had been performed successfully. In both cases the gas channeled within days to offset wells with little incremental recovery. The offset wells affected were located in the northeast/southwest natural fracture trend. The offset wells were shut in and allowed to soak and the input well was shut in after the designated volume was injected. Both the input wells and the offset wells had production increases. The exhaust gas increased the production six times over the initial production rate, and after two years of production response, the estimated ultimate recovery is O.85MCF/bbl. In the cyclic rich gas the ultimate recovery is estimated to be 3.3MCF/bbl. With no significant increase in operating cost, the primary cost of the process was in the investment in gas supply and injection.
These additional tests show that in a light oil pressure- depleted resefl'oir with natural fracturing. cyclic rich gas and cyclic nitrogen/carbon dioxide mix can yield excellent recovery efficiencies, and can be more efficient than cyclic carbon dioxide,
P. 501
A New Way of Optimising Contract Management and Co-operation Between Operator and Service Company
Authors: Torsvoll A. , Grotmaol O. 
Published: December 2007

Abstract
This is a summary of the added value obtained in a Joint Business Development (JBD) between an operator and a service company. The business development is founded in a Joint Operations Agreement formalised and signed by both parties early 1996.
This business development is unique because of its structure, and its systematic approach to jointly improve quality, communication, developing technology to meet needs, and the resulting added value to both parties.
This project was started in 1994 with a restructure of operators contract portfolio. The goal was to achieve improved cost efficiency, closer co-operation with suppliers and to reduce overall contract administration.
This was to be achieved by reducing overall number of contractors, combined with, transferring increased responsibility to the service company.
This system together with other Non Conformity and Health, Safety And Environment systems are used by both parties to focus on quality, and optimise resource use.
A system to identify gaps in behaviour, communication and expectations was also put in place.
Once the measuring systems were operational, a initiative was taken to do a large scale co-operative survey, focused on both technological and co-operational improvement opportunities. The result of the survey was then used to establish project specific Quality Action Teams with representation from both parties.
This way of working together has resulted in demonstrated improvements, that has given added value to the parties in several critical areas.
The process is under continuos development, and based on experience to date, the parties are preparing to take appropriate elements of the Joint Business Development process to the international arena.
P. 589
Production Management of Electric Submersible Pumps Using Expert System Technology
Authors: McLean Dan , Clay Roger , Gould Wayne 
Published: December 2007

Abstract
Management of electric submersible pumps (ESP) at wellsites can be improved using expert system technology to combine real time sensor information with production engineering knowledge rules. When abnormal conditions exist on an ESP well it is not always apparent that there is a problem until significant production loss and/or the results of pump damage become apparent. By applying expert system technology and elements of artificial intelligence, visualization of well performance in relation to the pump manufacturer's operating limits can be presented to operations personnel in real time. The well performance can then be maximized once the operating constraints are known and algorithms to optimize production can logically follow. The expert application described in this paper demonstrates this ability and can be extended easily to multiple well sites. The application was written for production at ARCO Alaska's West Sak field in parallel with the field development. The primary objective is to reduce operating and maintenance Costs by providing virtual operations assistance so that new wells can be operated and optimized using existing operations personnel.
P. 617
Calcite Scaling Tendencies for North Sea HTHP Wells: Prediction, Authentication and Application
Authors: Jasinski Raymond , Fletcher Philip , Taylor Kate , Sablerolle Willem 
Published: December 2007

Abstract
Calcite scale is generally encountered during hydrocarbon production in the North Sea. The optimization of completion design for both inhibition and remediation requires accurate forecasting of when a treatment will be required and how much treatment will be necessary. In this paper application of four water chemistry simulators to these objectives will be described for two HTHP waters, and two fields operating under less stringent environmental conditions. It will be shown that computer simulation of this scale formation chemistry becomes increasingly difficult for formation waters with temperatures above 250F and 6000 psi. We also describe the technology involved in designing a rigorous simulation model capable of simulating calcite scaling under these HTHP conditions, as well as validation of the model predictions vs. laboratory and field data.
P. 661