bluuebunny/crossref_metadata_2025_split huggingface dataset:
Deconvolution of Multiwell Test Data
Authors: Levitan Michael M. 
Published: January 2008

Summary
The deconvolution analysis technique that evolved with development of the deconvolution algorithms by von Schroeter et al. (2004), Levitan (2005), and Levitan et al. (2006) became a useful addition to the suite of techniques used in well-test analysis. This deconvolution algorithm, however, is limited to the pressure and rate data that originate from a single active well on the structure. It is ideally suited for analysis of the data from exploration and appraisal well tests. The previously mentioned deconvolution algorithm can not be used with the data that are acquired during startup and early field development that normally involve several producing wells.
The paper describes a generalization of deconvolution to mul-tiwell pressure and rate data. Several approaches and ideas for multiwell deconvolution are investigated and evaluated. The paper presents the results of this investigation and demonstrates performance of the deconvolution algorithm on synthetic multiwell test data.
The Resiliency of Frac-Packed Subsea Injection Wells
Authors: McCarty R. A. , Norman W. D. 
Published: January 2008

Abstract
This paper documents the utilization of fracpack completion technology for water injectors in sand control environments. This paper is a look back after five years of operation. It includes a review of the goals of the project and issues that occurred during the operation of the field. There is a discussion of the influence of the installation execution quality, the resulting injectivity index, analysis of the Hall Plot for the wells, analysis of the pressure decline from recent field shut-in, assesses the injection pressure versus the fracture pressure and comments on the tubing change out workovers. The results indicate that the fracpack completions are a very resilient and robust sandface completion for injectors. They have allowed injection below fracture pressure even after five years of injection with more than 400 emergency shut downs, cross flow, and filtration bypass.
Gas-Lift Hybrid Application in Offshore Northwest Java Production Sharing Contract
Authors: Santoso B. T. , Priyandoko P. , Harahap Boyke 
Published: January 2008

Abstract
Wells in X-ray area of Northwest Java Production Sharing Contract were all produced by Electrical Submersible Pump (ESP) system until gas zone was discovered in XM area in 1987. During development drilling, gas zone was discovered in XM structure 4 miles from the southern portion of XA filed. The gas zone was tested to be sufficient in term of pressure and gas volume for the support of a local gas lift project. The gas zone were then completed as a source gas to supply gas lift for all the XMA wells. Recently, the source gas has somewhat depleted to maintain all the production wells in that area. For that reason, several wells need to be selectively shut in. As pressure of gas depletes, the conversion from gas lift (GL) to ESP wells, as primary artificial lift mechanism is required. To minimize the down time period during ESP change out, ESP- GL hybrid was proposed to take the advantage of the limited source gas availability. This action allows the wells to continue on production while scheduling a pulling unit to replace the failure ESP.
Geometry, Internal Heterogeneity and Permeability Distribution in Turbidite Reservoirs, Pliocene California
Authors: Davies D. K. , Hara P. S. , Mondragon J. J. 
Published: January 2008

Abstract
This paper presents a reservoir model of the geometry, internal heterogeneity and permeability distribution in deep water, unconsolidated turbidite sand reservoirs of Wilmington Field, California. These reservoirs were deposited in a variety of environments associated with a deep-sea submarine fan system. The external form and internal heterogeneity of the reservoirs is controlled fundamentally by depositional environment. Production (rate and volume) is anisotropic and parallels the depositional trends. Production data indicate relatively high sweep efficiency and preferential permeability in a NE-SW direction (down depositional dip). Permeability and porosity are only weakly related to grain size. Sorting (standard deviation of grain size) and skewness (asymmetry of the grain size distribution) are the fundamental controls on porosity and permeability.
Rock-based log models of permeability and internal reservoir heterogeneity are developed based on detailed integration of core and wireline log data, specifically data related to pore geometry. Development drilling demonstrates that areas of the field with the highest values of porosity x thickness (PhixH) and lowest water saturation x thickness (SwxH) do not necessarily have the highest permeability and productivity. Areas with high productivity can have moderate values of PhixH and SwxH, but are characterized by high values of permeability x thickness.
In high porosity turbidite reservoirs, pore geometry based log models of permeability and reservoir heterogeneity allow for improved petrophysical evaluation, specifically net pay determination and prediction of producibility.
Identifying and Evaluating Producing Horizons in Fractured Basement
Authors: Tandom P. M. , Ngoc N. H. , Tjia H. D. , Lloyd P. M. 
Published: January 2008

Abstract
This paper will describe the results of development drilling to date in the basement reservoir of the Ruby Field in the Mekong Basin, Offshore Vietnam.
The results of joint research on the Ruby discovery wells and onshore basement exposures (Peter M. Tandom et al. 1997) were used to develop an interpretation model for the fractured and weathered granite reservoir. This model has proven very robust, and has now been further enhanced by applying more quantitative formation evaluation techniques to determine fracture aperture and porosity. Various acquisition techniques and computation algorithms have been tested to come up with an optimized logging program; giving consistent results compared with core analysis and production data.
It is now possible to predict with some certainty the most prospective hydrocarbon bearing intervals, and work is currently being focused on the estimation of likely production rates. Failure to meet the expected well deliverables provides a criteria for identifying candidates for stimulation. These techniques will also be reviewed.
As more wells are drilled, it has become possible to better correlate and map the producing horizons. This clearly allows better planning of the location of future wells, and the thickness of the reservoir section which needs to be penetrated, so optimizing field economics.
Best Practice Methods For Offshore Pipeline Installation In Sensitive Shallow Water Marine Environments
Authors: Hyams M. , Gorham R. , Howitt L. , Dixon K. 
Published: January 2008

Abstract
This paper outlines the environmental management controls successfullyimplemented during the construction of two offshore mini-platforms andassociated pipelines located in environmentally sensitive shallow tropicalmarine waters in the North West Shelf area of Western Australia.
The innovative barge anchoring methods implemented during the installationof the pipelines were successful in ensuring that no significant damageoccurred to the 1,300 coral bomboras surveyed within both pipelinealignments.
These projects serve as a case study demonstrating that the installation ofpetroleum facilities can be successfully undertaken in sensitive marineenvironments with no adverse environmental impacts on sensitive seabed habitats.
Is Your HS&E Management System Effective?
Authors: Brasher Ana , Featherly Janey 
Published: January 2008

Abstract
Today's business climate requires higher production levels at a competitive price while ensuring our business activities create no harm to people or the environment. To achieve this goal most companies have selected the HS&E Management System Approach based on the ISO 14001, OHSAS 18001 and Plan, Do, Check, Act principles. But how do you determine if your management system is adequate and effective to produced desired outcomes?
This paper will explore the ways that effective management systems are monitored on an ongoing basis and how that data is used to determine effectiveness of the system and drive continual improvement. Reviewing of the system begins with linking the commitments of an organization's policy statement to business objective. After this relationship has been identified appropriate performance measures are selected which allow management to monitor and evaluate the effectivness of the system. Finally, how are the commitments from the policy, business objectives and performance measures used to determine whether the system is adequate and effective to continually improve performance.
Drilling Wellbore Stability in the Compacting and Subsiding Valhall Field: A Case Study
Authors: Kristiansen Tron Golder 
Published: January 2008

Summary
Valhall is a field development located in the southernmost part of the Norwegian Continental Shelf. The chalk reservoir is weak and started to compact when oil production was initiated in 1982. The reservoir compaction was soon after observed at the seafloor in form of seafloor subsidence. Drilling was initially not a major challenge at Valhall, but as the reservoir depletion, compaction, and subsidence continued through the 90s, one had to develop drilling strategies to handle the associated reduction in frac gradient in the reservoir as well as the increasing problems experienced in high-angle ERD wells in the overburden. The problems in the overburden were associated with the compaction and subsidence and were most problematic in high-angle wells. An important factor in supporting the drilling teams in their decision-making process has been the development of wellbore stability models and the integration of drilling engineering and rock mechanics with subsurface technology. This paper briefly reviews the drilling history at Valhall prior to the ERD program initiated in the mid-90s, and more in detail the increasing problems in the late 90s in the ERD wells, where several very expensive wells did not make it to the reservoir target to produce oil. The paper reviews the work that supported the abandonment of the ERD program in favor of unmanned platforms in the North and South flank of the field, which resulted in the current drilling performance of the flank reservoir targets today being achieved with best-in-class drilling performance.
Gecko Wells: Bringing Sand to Surface, A Change in Well Design Philosophy
Authors: Ahmad Pg. Md. Fadilla Pg. Hj. , Ward Mike , Fisher Antony 
Published: January 2008

Abstract
Following an energetic, low unit development costs (UDC) workshop held by the Brunei Shell Petroleum (BSP) Darat asset team, with cross discipline, service company, and other low cost operator input, a fundamental change in well design was proposed. The Seria oilfield, managed by the BSP Darat asset group, is a billion barrel field that has been producing for over 60 years. As with most Brownfield sites, continued production faces a constant challenge to keep UDC economic. One of the major costs and well design requirements in this shallow oilfield is down hole sand control. It was proposed that if well design could be slimmed down, simplified, and sand produced to surface to be dealt with there, a significant reduction in well costs could be possible, even allowing for increased OPEX.
The paper will describe the change in well designs, the dynamics of a multi discipline team set up to manage this project, the drilling and completion of the wells, and the well start up process. Results from the wells will be presented along with future plans for the project, and …… why they were called Gecko wells!
Analysis of Spontaneous Capillary Imbibition for Improved Oil Recovery
Authors: Nurkamelia Nurkamelia , Arihara N. 
Published: January 2008

Abstract
Spontaneous water imbibition is an important recovery mechanism in water-flooding particularly in naturally fractured reservoirs. Scaling the core test data of spontaneous capillary imbibition with different injection fluids is crucial to properly design improved recovery methods and to predict their performances.
Spontaneous capillary imbibition experiments were performed under static co-current conditions, and recovery curves for brine and chemicals solutions were used for scaling the data in different cores and different interfacial tensions. Capillary Pressure and global mobility at water saturation behind imbibition front (Swf) were also extracted from the imbibition data of brine and chemical solutions. Relative permeability experiments were conducted at initial water saturation (Swi) and after imbibition.
Spontaneous imbibition of chemical solutions produced higher ultimate oil recoveries than brine imbibition. The scaling approach proposed by Li and Horne yielded satisfactory correlations for all the cases. Water relative permeability curves measured after brine imbibition showed close agreements with those measured at Swi, which suggests that we can save substantial time by sequentially conducting spontaneous imbibition and flooding tests. Finally, the global mobility was evaluated with those calculated at Swf from imbibition data and those calculated from the relative permeability data.
Effects of Oil-Water Mobility on Injectivity Impairment due to Suspended Particles
Authors: Altoé F. J. E. , Bedrikovetsky P. , Gomes A. C. A. , Siqueira A. G. , de Souza A. L. S. 
Published: January 2008

Abstract
Injectivity decline during sea/produced water injection is a wide spread phenomenon in offshore and onshore waterflood projects. It happens due to solid and liquid particles suspended in the injected water; their capture by the rock results in the hydraulic resistivity increase. The field injectivity decline history is used for characterisation of the formation damage system and consequent well behaviour prediction.
The injectivity index increases M times during the damage-free displacement of oil by water (M is the water-oil mobility ratio). It affects the well injectivity prediction during poor quality water injection and changes the results of injectivity decline curves interpretation.
We study the combined effect of the particle suspension injection and of the total oil-water mobility variation on well injectivity. An explicit formula for injectivity decline due to both effects was derived. The effect of the total oil-water mobility variation on injectivity is particularly significant for cases of heavy oil and relatively low formation damage.
The injectivity decline formula derived allows for determination of filtration and formation damage coefficients and filter cake permeability from the well injectivity history. Two examples of well data treatment for the deep-water offshore reservoir A (Campos Basin, Brazil) are presented.
A Semi-Analytical Method to Predict Well Deliverability in Gas-Condensate Reservoirs
Authors: Chowdhury Nitin , Sharma Ravi , Pope Gary A. , Sepehrnoori Kamy 
Published: January 2008

Abstract
A fine-grid simulation is needed to capture the build up of a condensate bank near wells operating below the dew point pressure. However, full-field simulations with a sufficiently fine grid will often not be feasible or will require very long computational times. A semi-analytical method has been developed that can be used to accurately predict the gas and condensate production rates from such wells and that has some advantages over the pseudo pressure approach. The semi- analytical method includes the effects of capillary number (high velocity) and non-Darcy flow. The new method has been implemented in a compositional reservoir simulator and verified with fine-grid compositional simulation results for both lean and rich gas-condensate fluids. Pressures, saturations, relative permeabilities, viscosities and densities calculated with the semi-analytical method are in excellent agreement with the results of fine-grid compositional simulations. Coarse grid simulations with grid block sizes on the order of 200 ft coupled with the semi-analytical method in grid blocks with wells yielded production rates as accurate as fine grid simulations with grid block sizes on the order of 2 ft. The method was tested for single-layer, multi-layer and multiwell gas-condensate reservoirs and found to give accurate results.
The Impact of Faults Representation on History Match and Future Generated Seismic Impedance Response in Reservoir Models—Case Study for Pierce Field, North Sea
Authors: Al-Busafi B. , Fisher Q. J. , Harris S. D. , Kendall M. 
Published: January 2008

Abstract
Transmissibility multipliers provide a simple way of accounting for the effects that faults have on fluid flow in production simulation models. Recent studies have shown that transmissibility multipliers can be quantified from parameters such as fault thickness and permeability (Knai and Knipe, 1998; Manzocchi et al., 1999). Generally, these latter parameters must be approximated using empirical relationships with some host rock properties such as V-shale or net-to-gross ratio as well as fault displacement magnitude (Manzocchi et al., 1999).
In this study, the effects of two different representations of faults on the history match and the predicted (simulated) seismic impedance are compared for the Pierce Field, North Sea. In the first case, fault transmissibilities were adjusted and the faults were extended in a trial and error manner to improve the match to fluid contacts and production history. In the second case, a step-by-step derivation of the fault transmissibilities in the Pierce Field was adopted based upon the integration of collected and upscaled properties of the deformed and undeformed reservoir as well as empirical relationships between fault offset and thickness. Historical production data were used to compare the effectiveness of the two methods. Furthermore, a synthetic seismic impedance response was generated from both simulation models, using a velocity model based on the Gassmann-Biot theory of elastic wave propagation in fluid saturated porous solid (Gassmann, 1951; Biot, 1956). This allows the assessment of different fault representations when trying to predict optimal times for further time-lapse seismic surveys. The results demonstrate the effectiveness of the derived transmissibilities model in generating a satisfactory history match in a relatively short time period. The generated seismic models show that, by acting as baffles/barriers to fluid flow, faults can play a major role in creating residual seismic features that can be observed on 4D seismic surverys. Incorporating realistic fault rock properties into the simulation model, which is used to create synthetic seismic, can therefore allow geophysicists and engineers to better plan the timing of 4D seismic surveys so that they have the greatest influence on field development decisions.
A Simulator For Produced Water Reinjection in Thermally Fractured Wells
Authors: Detienne J. L. , Ochi J. , Rivet P. 
Published: January 2008

Abstract
The objective of the analytical simulator presented here is to predict the opposite and complex effects induced by the injected produced water temperature and formation damage on thermally fractured wells. The deposition of solid particles and oil droplets in a fracture and its effect on the Injectivity Index evolution of an injector is then simulated. The principle is to inject cooled waters like sea water for example during a certain period of time to enable the well to develop a thermal fracture. When the fracture is well established, the re-injection of hot produced waters starts. The model takes into account the effect of this new water temperature on the viscous flow and on the fracture shrinkage and closure. In the same time oil droplets and solid particles contained in produced water cause the damage of the reservoir. This tends to open and propagate the fracture under bottom pressure increase. In the simulator, the internal formation damage and the external filter cake deposition in the fracture occur simultaneously. Two internal formation damage deposition models are taken into account. In a first model the internal damage is supposed to be linear and occurring from the fracture faces to the reservoir. In a second model, despite the growth of the fracture, the internal damage is supposed to be radial and occurring from the wall of the well to the reservoir. Also, two exeternal filter cake deposition models are considered: the filter cake deposits only at the fracture tip or on fracture faces. Theoretical field cases were considered in the simulations. The different internal formation damage and filter cake models were combined together to reproduce the injectivity index evolution observed on real fileds. The example presented are chosen to show that, contrarily to common thinkings, the II evolution can be dominated, in certain circumstances, by the internal damage rather then by the external filter cake deposition. With the present choice of data, the II evolution which matches better the commonly observed field reponses is obtained when the internal damage occurs in radial flow whatever the model deposition of the external filter cake is.
Advanced Drilling Using a Spiral Kelly
Authors: Girde P. 
Published: January 2008

Abstract
Conventional drilling techniques utilize a very important member in the drill string a ‘Kelly.’ This is about 45 ft. long and either a square or hexagonal cross-section. The main aim of this Kelly is to transmit torque to the drill string. This drilling technique results in low penetration rates, bulky drilling assemblies and high trip time. This paper adopts a new idea for the Kelly. This Kelly is spiral in its length and has a corresponding two piece Kelly bushing which is also spiral in nature. These spiral transmission systems are very commonly seen in many industries especially the heavy earth moving machinery and to a smaller extent in the automobile industry. They have a major advantage over all other transmission systems, such as much controlled penetration rates, because of the availability of maximum surface area. Grooves are highly efficient. In addition, slippage is totally eliminated, wear and tear is reduced to a minimum and high torque is easily transmitted. In this design, the kelly bushing is similar to that in a conventional system. Since the spiral kelly can take an enormous amount of load, jarring actions can be very easily done while the kelly is rotating. To implement the advantages of spiral Kelly I have designed a derrick having only 65ft height, Here we are using a two-piece bushing with balls placed inside the grooves which gives rise to less wear and tear as well by making the balls to circulate through the bypass line we can transmit only rotary motion so that in the case we encountered a hard formation the controlled penetration rate could be obtained The system is cost effective reducing rig time, as well it can be a best substitute for the normal drilling and workover derrick
Acid Number Measurements Revisited
Authors: Fan Tianguang , Buckley Jill S. 
Published: January 2008

Summary
We propose an improved procedure for measuring acid numbers. Major changes include spiking crude oil samples and blank solutions with a known amount of stearic acid to force a clear titration endpoint, replacing potassium hydroxide with tetrabutyl ammonium hydroxide in the alcoholic titratant, and correctly accounting for changes in electrode response that occur upon exposure of the electrode to crude oil.
Effect of Cyclic Loading on the Microtensile Bond Strengths of Total-etch and Self-etch Adhesives
Authors: Toledano M. , Osorio R. , Albaladejo A. , Aguilera F. S. , Tay F. R. , Ferrari M. 
Published: January 2008

Clinical Relevance
Resin-dentin bonds, which may have an influence on the long-term success of restorations, are prone to deterioration after cyclic loading. The tested one-step self-etching system (Etch&Prime 3.0) provided the least reliable dentin adhesion. After acid etching of dentin, alcohol/based adhesives performed better than those containing acetone as solvent.