bluuebunny/crossref_metadata_2025_split huggingface dataset:
Production Improvement of Formation Damaged Wells by Proper Acid Treatment
Authors: El-Halib Ismail Mohamed 
Published: February 2010

Abstract
Restoring the well's productivity from existing damaged or partially damaged formations has been the objective of many operators over the years. The damaged or partially damged formations requires to diagnose the causes of the damage in order to design the proper stimulation treatment to remove the damage and restore the well productivity. Drilling fluid, completion fluid and kill fluid have the potential to be the most damaging portion of reservoir life.
Integration of Pressure Buildup Deconvolution with the Rate-Normalized Pressure
Authors: Ortiz Rubiel , Davani Ehsan , Tran Tan , Sinurat Pahala , Ehlig-Economides Christine A. 
Published: February 2010

Abstract
Pressure transient analysis (PTA) is typically performed on pressure BU data acquired over a period from a few hours to a few days, while production data analysis (PDA) is performed with production data acquired over a period of a few days to several years. Recent approaches to extending a pressure BU response by deconvolving production data seem promising, but simple rate-normalized pressure (RNP) and its derivative may be more straightforward provided redundant data and artifacts are eliminated in the RNP processing.
This paper offers a unified PTA-PDA analysis combining pressure BU deconvolution with the RNP. Using the RNP as the indicator of the late-time behavior, the unified PTA-PDA analysis can provide a virtual constant rate drawdown response for the duration of the production data including the early time response from a selected pressure BU transient. The virtual pressure change and, in particular, its derivative provide trends easily identified as flow regimes suggesting model features that must be included in a simulated drawdown intended to match the unified response.
A model match with the virtual drawdown resulting from the unified PTA-PDA analysis offers a model consistent with the entire production history that can be used to forecast future production behavior and reserves for the well. Synthetic and field examples illustrate the approach.
Optimizing Simulation Studies for Gas Condensate Field Development and Management
Authors: El-Banbi Ahmed 
Published: February 2010

Abstract
Two field case histories to illustrate the techniques in simulation of gas condensate fields for field development and reservoir management are presented with emphasis on how to speed up the study work without reducing the accuracy of the results. One field case has been chosen as a "green field" development case, and the other as "mature" gas condensate redevelopment. Both fields were near critical reservoirs and an integrated approach was followed in developing the static and dynamic models.
For the green field case, the model was used to suggest new well locations and forecast production. For the mature field case, the model was used to optimize the performance of the field, increase recovery factor, and accelerate production. Several techniques were employed to facilitate the history matching and prediction runs. These techniques included the use of Modified Black Oil (MBO) approach, breaking down the model into smaller sectors to take advantage of isolated fault blocks and geological layers, a systematic procedure for history matching, and the involvement of field operation guidelines in designing the prediction runs. These techniques resulted in significant time savings in the study and allowed the study team to dedicate most of their time and effort to field development optimization. The model was changed to compositional model to investigate the effect of gas cycling and compare it to other alternative development plans. A detailed economical model was also built and coupled with prediction runs to select the most economical development plan.
Phase Behavior Aspects of Carbon Dioxide (CO2) Miscible Flooding in Tight Cores: A Case Study
Authors: Rahman Saifur , Nofel Wasef , Al-Majed AbdulAziz , Arshad Aziz , Menouar Habib 
Published: February 2010

Abstract
Carbon dioxide flooding process has been a proven valuable tertiary enhanced oil recovery technique. Although the petroleum industry has been applying the technique to produce heavy oil, it can be an effective tool to yield appreciable recoveries from complicated formations to produce comparatively lighter oil. The focus of experimental studies has been on the production of heavy oil and Carbon dioxide application to a wide range of other geological conditions and for wide range of petroleum fluids has been a less traversed path. Especially the process can be applied to tight formations where normal production procedures are not economically viable. This unviability may be due to rock or rock-fluid interactive properties. A research program for evaluation of the feasibility of development of such tight formations in the Middle East has been initiated. The research work included determination of minimum miscibility pressure (MMP), CO2 Core flooding and phase behavior investigation. Since both these processes are governed by the phase behavior; an investigation of phase behavior and PVT properties of reservoir fluids when combined with carbon dioxide are an integral part for a complete evaluation of crude oil extraction process. This paper presents the experimental and simulated phase behavior data for various mixtures of a live crude oil and carbon dioxide. The data helped in designing of the slim tube investigations and core flooding experiments.
The phase behavior during a CO2 flooding is a very complex process. Three mechanisms; oil swelling, reduction of oil viscosity, and the acidization of carbonate help obtaining better recovery in a CO2 flooding process. First two are the mechanisms boosting the miscibility between CO2 and reservoir oil. The other parameters which effect phase behavior during a CO2 flooding are the temperature, pressure and rock-fluid interactive properties of the reservoir. Carbon dioxide can be first contact miscible with crude oils, but usually at very high pressure. Attaining and operating a flooding process at these pressures is not financially desirable. Multi contact miscible process is preferred as the economical process for the carbon dioxide flooding.
The phase behavior of the original oil and after addition of different amounts of CO2 was studied by performing Constant Composition Expansion (CCE) tests. The bubble point pressure determined for the original oil sample and with increasing carbon dioxide. The phase behavior properties like bubble point pressure amount of liquid for the mixture with carbon dioxide range matched well with Equation of State (EOS) simulations. A comparison of the average density of the crude oil CO2 mixtures confirmed the swelling process. A material balance study between the injected and produced material from the core was also done for verification.
Optimizing Development Well Placements within Geological Uncertainty Utilizing Sector Model
Authors: Mesdour Rabah , Ramsey Lee , Aly Ahmed 
Published: February 2010

Abstract
Uncertainties particularly in geological parameters are always present and can be significant if associated with field development. These uncertainties could be perceived by geologists and engineers to exist in the available data. Industry has been using uncertainty analysis to identify, address and mitigate risk. Development strategies and well placement may significantly depend on field geology, maturity of the depletion stage, technological factor, drive resources and other parameters. Well placements optimization most of the time is done based on a deterministic (most likely) case. The optimum placement of wells within geologic uncertainty is the issue addressed in this paper.
This paper discusses a new approach and workflow process for applying uncertainty analysis using sector model of an undeveloped reservoir and the optimization of development wells under geological uncertainty. Tornado plots were used to identify the highest critical parameters among the list of uncertainties of the field. Experimental Design was used to select simulation runs to build the proxy model. Monte Carlo analysis was then used to generate the density distribution function of cumulative production to identify the P10, P50 & P90 cases. The probabilistic distribution was used to determine the likelihood of the development case under identified risk parameters. Field operation strategies were considered together with optimization of injector-producer spacing, producer-producer spacing, horizontal completion, well length and orientation with geologic uncertainties. The optimized development plan and well placements were used to generate the cumulative production distribution with uncertainty parameters. This workflow was successfully tested in a large carbonate field.
One Dimensional Modelling and Experimental Validation of Gelled Waxy Oils Restart
Authors: Margarone Michele , Borghi Gianpaolo , Correra Sebastiano 
Published: February 2010

Abstract
Flow restart after a planned or emergency production shut-down of waxy oil offshore pipelines is a concern to operators. Since reliable methods to predict the required time and input pressure are not available, there is a high risk to lose a transportation or production flow line. So far most of predictive models have been based upon the assumption that gelled crude behaves as an incompressible high viscous fluid. Field cases and laboratory model pipeline tests have shown however that these calculations give systematically overestimated restart pressures, giving the opportunity to lower investment development schemes (such as less insulated pipelines or no extra pumping requirement). Since offshore oil industry is facing more and more challenging production environments, such as deepwater and marginal fields with long tiebacks, this issue is becoming even more stringent, affecting directly the investment cost required for the development of waxy oil resources.
The aim of this work was to investigate the problem of restart of waxy crude oils and preliminarly to present a new mathematical model as a robust pipeline restart predictive tool with a sound physical basis. Although this topic has been investigated for more than forty years, until recently, when Vinay et al (2006, 2007) and Wachs et al (2009) developed a theoretical framework for start-up transients of compressible yield stress fluids, no one had considered the old and simple plastic Bingham Model (BM) (Bingham, 1919). Beyond the model description, a first analysis comparing model forecast with experiments carried out in a model pipeline with multiple pressure taps at constant injection flow rate was carried out.
Technology and Innovation: Do We Do Enough in Our Industry?
Authors: El-Banbi Ahmed 
Published: February 2010

Abstract
This paper compares the petroleum industry with other industries from the technology development aspect. The comparison is based on studying financial as well as Research and Development (R&D) investment data for the Fortune 500 companies.
Our industry has been coping with increased hydrocarbon demands by responding to increased challenges to find and produce more hydrocarbons through developing new technologies. Some of the historical key technologies in the petroleum industry are reviewed. The current challenges requiring new and novel technological developments in our industry are also highlighted.
We followed a systematic analytical approach to investigate and compare technology development in the petroleum industry with other industries through investigation of public company data for the Fortune 500 companies in addition to major petroleum and major service companies. The investigation reveals an interesting correlation between the profitability of a company and its R&D investment. Also, and within the same industry, companies which invest more in R&D seems to enjoy superior profits over their competitors. Although the oil industry invests significant amounts of money in technology development, it spends less than other industries in both R&D spend as percentage of revenue and the actual amount of money spend.
Control of Pressure Dissolution and Quartz Cementation on the Reservoir Quality of Glacial Ordovician Sandstones from the Sbaa Basin, Algeria
Authors: Tournier F.. , Portier E.. , Pagel M.. 
Published: February 2010

Abstract
GDF SUEZ and Sonatrach will develop in partnership the main fields of the prolific Sbaa basin, SW Algeria. In this area, the main gas reservoir is composed by the glaciogenic Upper Ordovician, which exhibits high poroperm heterogeneities, with porosity and permeability ranging from 1 to 15% and 10−3 to 103 md respectively. The low permeability zones are generally encountered in the lower units of the reservoir and no obvious geological control has been interpreted so far. According to previous studies, quartz cementation and pressure dissolution are responsible for these low petrophysical properties. An extensive diagenetic study was then undertaken to understand the origin and the distribution of these diagenetic processes and their impact on the reservoir architecture (Tournier et al., submitted). It underlines the role of the glaciogenic processes, responsible of clay coating development in underlying clean sandstones. These clay coatings will determine afterwards diagnetic evolution of these sandstones by enhancing pressure dissolution. Produced silica is exported in low compacted upper layers and deposited as quartz cement (Tournier et al., submitted). In the present paper, two main petrofacies are distinguished by their dominant diagenetic features, either pressure dissolution or quartz cementation. This petrographical classification has strong petrophysical implication, and highlights the importance of these two diagenetic processes in the reservoir quality of these sandstones.
The two petrofacies described in this paper, QS1 and QS2, correspond to the distinction between conventional and tight reservoirs. The value of 5% porosity may be considered as the limit between the two types of petrofacies and provides a pertinent insight about porosity cut-off used in petrophysical properties evaluation of the glacial Ordovician sandstones of the Sbaa basin.
Shelf-to-Basin Floor Seismic Expression of the Rosetta System (Western Nile Delta, Egypt): A Modern Analogue of Deep-Water Reservoirs
Authors: Rouillard P.. , du Fornel E.. , Migeon S.. , Dauphin L.. , Mascle J.. 
Published: February 2010

Abstract
The need of modern analogues is critical for petroleum exploration, mainly for deep-water reservoirs because of their wide variability in term of size, thickness and lithological lateral changes that make them still difficult predict. Analyse of geometry and stacking pattern of "recent" (Plio-Quaternary) sedimentary bodies can greatly improve our ability to understand buried reservoirs. Because the Nile submarine delta is the largest area of gas exploration and production of the Mediterranean and because its recent history, architecture, source and factors controlling the sediment dispersion are now well constrained, the Rosetta turbidite system (western province off Nile Delta) is probably the best site to study of a silty/mud delta-fed turbidite system. The main goal of our approach is to propose a conceptual model of a delta-fed turbidite system construction and evolution through time.
A wide 2D and 3D-seismic data set from the shelf to the basin, respectively provided by GEOAZUR laboratory and GDF SUEZ was made available over the whole Rosetta system (western province of the Nile fan, off Egypt). Numerous sedimentary bodies have been characterized and discriminated along a dip synthetic profile and replaced within a relative chronological framework to build a depositional model of the system and to provide new insights on the architecture and stacking patterns of deep-water reservoirs.
The Rosetta system appears to be a rapid point-source migrating system driven by large-scale slope failures and sea-level fluctuations. During sea level falling stages, sediment transfer is constrained and channelized by scars at the shelf break resulting in the construction of small channels indenting the top of mass-transport deposits and depositing ponded lobes in topographic lows. As sea level drops, a short and narrow submarine canyon is progressively formed and the turbidite system progrades toward the basin floor. Sea-level lowstands favour the development of wide shelf-margin deltas, which are feeding and prograding over the canyon head that rapidly evolves in an unconfined meandering leveed channels system. Avulsion processes affect these leveed channels systems as the slope gradient changes due to regional salt-tectonics, crevasse splays, and they deposit wide distal-lobe complexes at their mouths.
This model might be used as a predictive model for gas reservoirs for the Kafr El Sheikh and El Wastani formations in the western part of the Nile Delta and, more generally, for any other unconfined delta-fed turbidite systems.
CCS Project in a Gas Field of the Sbaa Basin, SW Algeria - What is at Stake?
Authors: Mossé Y.. , Portier E.. , Schaaf T.. 
Published: February 2010

Abstract
GDF SUEZ and Sonatrach will develop in partnership the main fields of the prolific Sbaa basin, SW Algeria. In this basin, the main gas levels comprise the Cambrian and Upper-Ordovician reservoirs, sealed and sourced by the Silurian "Hot Shales" Formation. Average CO2 content of raw gas is in excess with regard to sales gas specifications. As a result, CO2 removal is required as part of gas treatment and it is intended to install an amine unit in the future Central Processing Plant for such purpose. Regeneration of the amine results in the release of significant quantities of CO2, which amounts to ca 1200 t/day. Looking for a solution to re-inject underground this CO2 was decided, within the project exploitation perimeter. Such an initiative has materialized with the achievement of a screening and feasibility study during the development conceptual phase, which identified the two best structures for underground CO2 sequestration. In both cases, CO2 should be re-injected in the aquifer, in the water leg, away from gas production area. A pilot well will be drilled to address the geological and reservoir uncertainties, so as to validate the concept.
For now, preparatory sensitivity studies, using Cougar® software (developed and marketed by IFP) were performed to identify key parameters controlling the CO2 re-injection performance. These probabilistic results show that, if effective permeability and reservoir heterogeneity are from far the main drivers, the mobility of fluid in place, such as gas or formation water, strongly controls the performance, ranging from 55 to 98 % of CO2 to be injected. Based on experimental design type of approach, this study enable to rank the main uncertain parameters (such as type of wells, number of injectors and maximum operating pressure) and to quantify their respective contribution to the underground CO2 storage performance.
This type of study helps to determine the priority in the data acquisition program of the future pilot well and to set-up the basis of design of the CO2 sequestration facility.
An Improved Grey Relation Analysis Method and Its Application in Dynamic Description for a Polymer Flooding Pilot of Xingshugang Field, Daqing
Authors: Feng Y.. , Ji B.. , Gao P.. , Li Ye 
Published: February 2010

Abstract
The industrial experience at Daqing showed that chemical flooding significantly could enhance the oil recovery. Meanwhile, the fluid behaviors in the reservoirs became more complex due to the injection of chemicals. The dynamic connectivity between injection and production wells formed by water flood has been changed significantly due to the participation of chemical solutions. In this research, an improved grey relation analysis method (IGRA) is introduced to predict the dynamic connectivity between injection and production wells and to estimate the effects of connectivity changes. Plenty of sensitivities in chemical floods are considered in this new method so that the influence of errors caused by a poor indices choice in the variable process description can be minimized. An application was carried out in a polymer flooding pilot of the Xingshugang Unit, Daqing. By comparing the results of both the water and chemical flooding prediction results with IGRA, the dynamic connectivity changes have been demonstrated. Tracer tests have been conducted for both water and chemical flood. The interpretations of the tracer tests have also proven the accuracy of predictions. The results of chemical flooding prediction have been used to adjust the injection and production rate for individuals.
Application of Group Method of Data Handling for Geological Modeling of Vankor Field
Authors: Semenov A. A. , Oshmarin R. A. , Driller A. V. , Butakova A. V. 
Published: February 2010

Abstract
One of the main issues while reservoir geological model creation is to establish the relationship between measured rock properties (e.g. porosity, permeability) and well logs values. Standard approaches consist in using deductive mathematical modeling algorithms to solve this problem. The primary objective of this study was to develop the best mathematical model for Dolgan reservoir rock characteristics estimation using all available well logs information. It is obvious that simple polynomial models for this area were not applicable due to special properties of water saturated. Matched rock properties lab measurements in reference wells and well logs data were available.
In the frameworks of this article several statistical methods including various regression types and neural networks were analyzed. The best relation in terms of statistical criteria was obtained by the group method of data handling (GMDH) method. GMDH is an inductive modeling algorithm using neural network with active neurons. This approach optimizes not only model coefficients for predetermine mathematical equation but also select optimal model complexity.
Multilayered algorithm of GMDH, based on polynomial reference function allowed maximizing amount of information being used from different types of well logs in reference wells for target relation. Data from neutron, density, resistivity and PS logs were the most significant for the final model of Dolgan resorvoir.
So using of GMDH cybernetics algorithms may significantly increase precision of rock properties forecast for further geomodeling purposes.