bluuebunny/crossref_metadata_2025_split huggingface dataset:
Management of Combined Ridge Defect and Osteotome Sinus Floor Elevation With Simultaneous Implant Placement—A 36-Month Follow-Up Case Report
Authors: AlGhamdi Ali Saad Thafeed 
Published: October 2009

AbstractThis report demonstrated the management of combined ridge defect and maxillary sinus pneumatization with simultaneous implant placement. One case with vertical and horizontal ridge deficiency and sinus pneumatization in the maxillary premolar area was indicated for ridge augmentation and sinus elevation before implant placement. Implant osteotomy was enlarged using a ridge expansion osteotome to 1 mm short of the sinus floor; sinus elevation was performed using sinus lift osteotomes; the implant was placed; bone graft and resorbable membrane were used to augment the remaining defect. The second stage was done after 6 months, followed by final restoration. The patient was reevaluated for 36 months following the final prosthesis. The surgical site healed without complication following implant placement. During the second stage, the implant was completely surrounded by bone, with bone covering the buccal aspect of the cover screw. The X-ray showed a 5 mm apical shift of the sinus floor at 6 months post surgery. At 12 months post loading, crestal bone loss to the level of the first thread was noted; no changes were observed at the sinus or surrounding teeth. Pocket depth ranged from 3–4 mm. No further bone loss or soft tissue contour change was noted at 18, 24, 30, and 36 months post loading. The combination of these three techniques with simultaneous implant placement as described in this report seems to be successful. Further research is needed to evaluate whether the combination of these techniques with simultaneous implant placement offers similar results when compared with the stage approach.
A Removable Snore Reduction Appliance for a Mandibular Edentulous Patient
Authors: Flanagan Dennis 
Published: October 2009

Abstract
A snore reduction appliance can be constructed for the atrophic mandibular edentulous patient. Two endosseous implants can be surgically placed that retain a complete mandibular denture and, in turn, an overlying bimaxillary removable snore reduction appliance. A dual laminate appliance is vacu-form fitted to the maxillary teeth and the mandibular denture and luted in a protrusive relation with cold cure acrylic. The appliance maintains the mandible in a protrusive position to open the upper airway to reduce snoring.
Platform Switching and Bone Platform Switching
Authors: Carinci Francesco , Brunelli Giorgio , Danza Matteo 
Published: October 2009

Abstract
Bone platform switching involves an inward bone ring in the coronal part of the implant that is in continuity with the alveolar bone crest. Bone platform switching is obtained by using a dental fixture with a reverse conical neck. A retrospective study was performed to evaluate the effectiveness of conventional vs reverse conical neck implants. In the period between May 2004 and November 2007, 86 patients (55 females and 31 males; median age, 53 years) were operated and 234 implants were inserted: 40 and 194 were conventional vs reverse conical neck implants, respectively. Kaplan-Meier algorithm and Cox regression were used to detect those variables associated with the clinical outcome. No differences in survival and success rates were detected between conventional vs reverse conical neck implants alone or in combination with any of the studied variables. Although bone platform switching leads to several advantages, no statistical difference in alveolar crest resorption is detected in comparison with reverse conical neck implants. We suppose that the proximity of the implant abutment junction to the alveolar crestal bone gives no protection against the microflora contained in the micrograph. Additional studies on larger series and a combination of platform switching and bone platform switching could lead to improved clinical outcomes.
Correlation for Prediction and Estimation of Capillary Pressure to Account for Wettability and Wettability Variations Within Reservoir—Part 2
Authors: Zahoor Muhammad Khurram , Derahman Mohd. Nawi , Yunan Mat Hussin 
Published: October 2009

Abstract
Wettability plays an influential role in fluid flow behavior within a reservoir. Despite of its importance, it is not usually given the required significance during simulation studies. Different types of wettability may exist or co-exist within a reservoir which may change with the passage of time, depending on the prevailing conditions within a reservoir and also on the fluids which are injected for the purpose of enhanced oil recovery. In order to account for the effect of such wettabiliy variations on fluid flow behavior, a set of correlations have been developed to estimate capillary pressure, when the data from the core at extremely water-wet conditions is known. In this paper the developed set of correlations are further modified, so that they can be used quite effectively, when the capillary pressure data for any wettability conditions is known.
Optimum Non Hydrocarbon Gas Injection Development Process and Ultimate Recovery Maximization
Authors: Abed Abdulla , Zekri Abdulrazzag Y. 
Published: October 2009

Abstract
A multi layered heterogeneous oil reservoir was selected for this study. The integrated reservoir characterization model and the pertinent transformed reservoir simulation history matched model were quality assured and quality checked.
The development scheme was identified and selected where the pattern and completion of the wells were defined to fit the heterogeneity of the reservoir characterization model. Lateral and maximum block contact holes were investigated.
The development processes studied were mainly hydrogen sulphide, carbon dioxide, nitrogen and rich hydrocarbon gas. The Water Alternating Gas/ Simultaneous Water Alternating Gas (WAG / SWAG) processes were also assured. In addition to the main gas and WAG/SWAG processes, many miscible and immiscible EOR processes were also investigated though the results are not presented but may be referred to.
Field development options based on the development and processes schemes as well as reservoir management and long-term business plans including phases of implementation were identified and assured. The development option that maximizes the ultimate recovery factor was evaluated and selected.
The main objective of this work was to define the development process that could give a maximum ultimate recovery factor of more than 70 %. This could increase the total technical reserves by 30 % over the reserves based on classical water flooding reserves. It may be said that the life of the field could be extended to be almost doubled. The best technically development process that gives a maximum ultimate recovery factor of more than 70 % was the H2S-WAG development process. The enriched-WAG development scheme can be designed to give an equivalent ultimate recovery factor by enriching the gas.
The N2-WAG development process gives a relatively poor recovery factor. This is the lowest of all the Non-hydrocarbon Gas Injection (NHGI-WAG) development processes investigated.
The Use of High Pressure MICP Data in Reservoir Characterization, Developing a New Model for Libyan Reservoirs
Authors: Aboujafar Sami Mo. 
Published: October 2009

Abstract
Mercury injection capillary pressure data have been widely used to charaterize reservoir rocks, evaluating sealing capacity for traps and to explain the locations of hydrocarbon accumulations and transition zones. This method can determine a broader pore size distribution more quickly and accurately than other methods. It can be used to characterize pores ranging from 0.003 pm to 360 μm using a single theoretical model. The data produced (mercury intrusion volume at various pressures) can be used to calculate numerous sample characteristics such as pore size distributions, total pore volume, total pore surface area, median pore diameter, and sample densities (bulk and skeletal).
In this study the application of the high pressure mercury porosimetry technique in determination of different reservoir parameters have been investigated and a comparison between clastic and non clastic reservoirs was made. This was done by using data obtained from forty core samples from sandstone and carbonate reservoirs in North Africa. The results of different measurements and techniques were processed and interpreted. Theses included calculating the capillary pressure curves for the two rock types, converting the air/mercury curves to subsurface conditions and making sensitivity analysis for different parameters such as interfacial tension and contact angle. The distribution of pore-throat sizes and thus understanding the structures of pore systems in the reservoir has also been investigated. Another petrophysical reservoir property which was examined by this method was the existence of different types of porosity, (micro, meso and macro), which can be derived from the pore size distributions and compared between the two rock types, and therefore an attempt was made to classify the different rock types present in the studied samples.
A set of Empirical relationships which relate absolute permeability to the pore throat size distribution, pore throats at different mercury saturations, were derived for each rock type, and then these relationships were more investigated by introducing the effect of porosity. Finally, an estimation of the pore size from routine core data was made and compared with the measured data. These empirical relationships were also compared with other available relatioships obtained by other authors such as Pittman and Winland.
Multi Component Mass Transfer in Multiple Contact Miscibility Test; Forward and Backward Method
Authors: Wan Nurul Adyani Wan Razak , Wan Daud Wan Ata , Faisal Ahmad Hisyam , Zakaria Nur Atiqah 
Published: October 2009

Abstract
Multiple contact miscibility test for both forward and backward technique was conducted on light live reservoir crude with the API value of 41.5°. The experiment was conducted in four stages. At each stage of the experiment, a small amount of liquid and gas were sampled out from the PVT cell for compositional analysis.The multiple contact miscibility test simulate the continuous multiple contact process when the injection gas Carbon Dioxide (CO2) is injected into the reservoir fluid. In this study, the injection gas was mixed with the crude oil to achieve equilibrium at reservoir pressure and temperature. Dynamic miscibility between oil and Carbon Dioxide, which was not miscible on first contact was achieved by in-situ mass transfer of components between phases. This mass transfer phenomena, however, is not the same for forward and backward method of multiple contact miscibility test. At each stages of the test, different component has been transferred between phases with different amount and rate.
The results indicate that the amount of methane in vapour phase had increased significantly, as the number of contacts increases for both forward and backward multiple contact tests. The intermediate fraction became lighter and lighter as the contact progress. While the heavier component that was left out in the liquid phase susceptible to flocculate and produce heavy deposit such as asphaltenes. The phase envelope for liquid phase was generated using PVTi software with compositional data as an input. The change in the phase envelope shape explained the process that happened at each stages of the experiment. Ternary diagram was build to explain the difference in extraction process between forward and backward multiple contact test.
In conclusion, for CO2, some period of immiscible displacement must occur before mass transfer between reservoir oil and the advancing gas front establishes dynamic miscibility. This phenomenon was observed for both backward and forwards multiple contact experiment.
Reservoir Rock Types Application - Kashagan
Authors: Francesconi A. , Bigoni F. , Balossino P. , Bona N. , Marchini F. , Cozzi M. 
Published: October 2009

Abstract
Kashagan is a world-class supergiant oil field located in Kazakhstan, in the offshore of Caspian Sea. The reservoir is an isolated carbonate platform, Devonian to Carboniferous in age.
Definition of petrophysically significant Reservoir Rock Types (RRT) is critical in the reservoir characterisation and the dual petrophysical-geological significance of these RRTs is fundamental in providing a link to geological model drivers.
Kashagan carbonate field core studies highlight no relationship between lithofacies and petrophysical characteristics because of the strong diagenetic overprint. A RRT classification has been therefore performed integrating petrophysical data, Phi-K-MICP, with sedimentological, diagenetical and petrographical data. This process has allowed the definition of 7 RRTs that have been propagated into the Log domain using the kNN algorithm.
The resulting Log RRTs have been analysed in term of spatial distribution and petrophysical meaning. Their main geological driver is the 4th order cyclicity with a link to the Environment of Deposition, Karst intervals and Diagenetic Reservoir Quality Maps. The 3D modelling of RRTs should be therefore driven by VPC per 4°order cycles, obtained for each 3° order System Tract, consistently with both EoD and RQ Maps.
Core plugs and whole cores, "labelled" according to Log RRT propagation, have been analysed and characterised in terms of both K vs. Phi and Sw vs. Height relationships. Whole cores RRT show, systematically, higher K vs. Phi trends. This fact has been interpreted as a scale factor. Whole core K/Phi relationships have been therefore utilized for the synthetic permeability estimation. The KH-RRTs vs. KH-Well-Test comparison shows a good agreement in Platform Interior where wells are mainly producing from matrix, while in the Rim a large gap, due to Fractures and Megakarst, has been recognized.
Structural Uncertainty Modelling and Updating by Production Data Integration
Authors: Seiler A. , Rivenæs J. C. , Aanonsen S. I. , Evensen G. 
Published: October 2009

Summary
An integrated reservoir characterization workflow, for structural uncertainty assessment and continuous updating of the structural reservoir model, by assimilation of production data, is presented. An ensemble of reservoir models, expressing explicitly the uncertainty resulting from seismic interpretation and time-to-depth conversion, is created. The top and bottom reservoir-horizon uncertainties are considered as a parameter for assisted history matching and are updated by sequential assimilation of production data using the Ensemble Kalman Filter (EnKF). To avoid modifications in the grid architecture and thus ensure a fixed dimension of the state vector, an elastic grid approach is proposed. The geometry of a base-case simulation grid is deformed to match the reservoir top and bottom horizon realizations. The method is applied to a synthetic example. The result is an ensemble of history-matched structural models with reduced and quantified uncertainty. The updated ensemble of structures provides a more reliable characterization of the reservoir architecture and a better estimate of the field oil in place.
Modeling CO2 Injection in a Fractured Chalk Experiment
Authors: Alavian S. A. , Whitson C. H. 
Published: October 2009

Abstract
This paper presents a modeling study of CO2 injection in a chalk core based on experimental data reported by Karimaie (2007). The experiment consisted of a vertically-oriented 19.6 cm long chalk outcrop core initially saturated with reservoir synthetic oil consisting of C1 and n-C7 at a temperature of 85°C and pressure of 220 bar. After saturating the core with the oil mixture by displacement a small "fracture" volume surrounding the core was created by heating the solid Wood's metal which originally filled the volume between the core and core holder.
Gas injection was first conducted using an equilibrium C1-n-C7 gas at 220 bar, resulting in no recovery by (thermodynamic) mass transfer but only from immiscible displacement with Darcy flow driven by induced pressure gradients and a minor impact of gravity-capillary equilibrium. Once oil production ceased in this first displacement, a second period with pure CO2 gas injection followed.
Our modeling was conducted with a compositional reservoir simulator. The 2-dimensional r-z model used fine grids for the core matrix and surrounding fracture. Automated history matching is used to match experimental data. The match to reported production data gave a high degree of confidence in the model. Oil recovery improved significantly by CO2 injection.
Our model study indicates that the recovery mechanism in the Karimaie experiment was dominated by Darcy displacement because of a low conductivity in the surrounding fracture. Another observation made in our study was the strong influence of surface separator temperature on surface oil production. Finally, gas injection rate changes had a significant impact on recovery performance for CO2 injection. Gravity-capillary recovery mechanism was of minor importance in the Karimaie experiments.
Application of the Infrasoinic Passive Differential Spectroscopy (IPDS) for Hydrocarbon Direct Detection and Reservoir Monitoring in Fields of the North-Caspian Basin: Achievements and Challenges
Authors: Makhous Monzer , Rode Paul Ernest , Kaya Serdar 
Published: October 2009

ABSTRACT
This technique is based on the principles that hydrocarbon reservoirs as a multi-fluids system in porous medium has an unconventional (non linear) transfer characteristics for acoustic waves. Hydrocarbon fluid in porous system can be detected as a characteristic deformation of the natural earth noise spectra in the acoustic low frequency range between 0.2 and 10 Hz. The anomalous absorption/emission of micro-seismic noise is used as source for direct detection of oil/gas accumulation (OGA) trapped in a porous matrix/reservoir.
In these conditions, the OGA passes in generation of its proper infra-acoustic waves. The mechanical energy of hydrodynamic nature is simply transforming in acoustic energy generating the IPDS waves/signals (downward conversion). The spectral amplitude of background micro-seismic emission above the OGA exceeds considerably that of outside the OGA in the frequency range of 0.1-30 Hz. Measuring and processing the characteristic spectral amplitude of this generated and amplified natural micro-seismic noise defines the presence or absence of OGA.
Applying this technology to three important fields in the North Caspian basin has shown that it provides a detailed spatial hydrocarbon distribution, reservoir delineation and monitoring and reliable estimation of hydrocarbon potential reserves or resting un-produced oils. Correlation of field production data with the passive seismic monitoring results shows an enough satisfactory output of the applied technology for reservoir monitoring. This technology could be also promising for EOR/IOR projects, as well as for horizontal and vertical well drilling projects.
However, in faulted disintegrated zones owing to increased heterogeneous stress as factor of both micro- and macro-seismic instability the IPDS signals are somewhat deformed. This fact implies some ambiguities, which have to be clarified and resolved.
Experimental K-value Prediction
Authors: Rahman Saifur 
Published: October 2009

Abstract
The Equilibrium ratios (K-values) depend on temperature, pressure and the overall composition of the reservoir fluid. Several correlations are being used and are considered accurate enough. But on close examining these correlations provide accurate results only at lower pressures. This is because at lower pressure the K-values are primarily dependent on pressure and temperature. The compositional dependence which is more complicated to model happens at higher pressures. The compositional dependence is believed to be only a function of convergence pressure. When we consider that predicting convergence pressure in itself is dependent on the correlations, we can fathom the cause of inaccurate prediction of K-values. We believe that there is not enough data available to generate accurate correlations. The inaccuracy of correlations in prediction of the K-values will be shown in this paper by comparison with the experimental data.

Introduction
Phase behavior data is one of the most important tools used to evolve reservoir development strategy. Knowledge of Vapor-Liquid-Equilibrium (VLE) data is essential for understanding the separation processes in the reservoir as well as in the surface equipment. This information helps in selection of equipment for flash separation at the well head, distillation columns and even for design of pipeline and unit operations. The thermodynamic equilibrium between vapor and liquid phases depend on equality of temperature, pressure, and fugacity of each component in both phases.
Akaike's Information Criterion in Packer Test Analysis
Authors: Rafiee M. M. , Haefner F. , Voigt H. D. 
Published: October 2009

Abstract
Gradient techniques are used predominantly in History Matching and Optimization. In this paper gradient technique was used in estimation of multiple packer test data (permeability distribution of very low permeable formations). A high pressure gas chamber has been released into the formation and pressure changes in this chamber and two nearby observation chambers have been measured.
A simulation model has been set up for this experiment and Eclipse black-oil simulator was used for simulation. By defining region multipliers close to packer tools and validating the model, the Gradient Optimization technique of SIMOPT-History Matching software has been used to find permeability multiplier in these regions.
Akaike's information criterion (AIC) concept which is the tradeoff between minimum of objective function and the necessary complexity of the reservoir description could be used plausibly to assess the uniqueness of the selected model. Although the Objective Function is reduced with increasing the number of parameters, AIC could estimate the most reliable unique solution avoiding an over-parameterization.
The proposed technique offers a way to estimate reservoir parameters at In-Situ reservoir conditions, accounting for heterogeneities and could prove reasonably the uniqueness of the selected model among different sets of identified solutions.
Rock Typing: An Integrated Reservoir Characterization Tool to Construct a Robust Geological Model in Abu Dhabi Carbonate Oil Field
Authors: Salman Salman M. , Bellah Sameer 
Published: October 2009

Abstract
Rock typing is an essential step in carbonate reservoir characterization and geological model building for reservoir simulation. A static rock type is defined as "a rock unit characterized by similar depositional and digenetic processes resulting in a typical and unique Ø-K relationship and capillary pressure curve at given wettability. Reservoir representative rock types lead to a better understanding of reservoir fluid movement and oil recovery.
This paper establishes a deterministic rock type scheme in a carbonate reservoir and presents a methodology to distribute these rock types vertically and laterally in the 3D geological model using wells data, conceptual model and reservoir structure map obtained from 3D seismic.