bluuebunny/crossref_metadata_2025_split huggingface dataset:
Concentrated sodium chloride brine solutions as an additional treatment for preventing the introduction of nonindigenous species in the ballast tanks of ships declaring no ballast on board
Authors: Santagata Scott , Bacela Karolina , Reid David F. , Mclean Kevin A. , Cohen Jill S. , Cordell Jeffery R. , Brown Christopher W. , Johengen Thomas H. , Ruiz Gregory M. 
Published: September 2008

Abstract
Currently, seawater flushing is the only management strategy for reducing the number of viable organisms in residual sediments and water of ballast tanks of vessels declaring no ballast on board (NOBOB) that traffic ports of the eastern United States. Previously, we identified several species of freshwater and brackish-water peracarid crustaceans able to survive the osmotic shock that occurs during open-ocean ballast water exchange and, potentially, to disperse over long distances via ballasted ships and NOBOB vessels. We tested the efficacy of concentrated sodium chloride brine solutions as an additional treatment for eradicating the halotolerant taxa often present in the ballast tanks of NOBOB ships. The lowest brine treatments (30 ppt for 1 h) caused 100% mortality in several species of cladocerans and copepods collected from oligohaline habitats. Several brackish-water peracarid crustaceans, however, including some that can survive in freshwater as well, required higher brine concentrations and longer exposure durations (45–60 ppt for 3–24 h). The most resilient animals were widely introduced peracarid crustaceans that generally prefer mesohaline habitats but do not tolerate freshwater (required brine treatments of 60–110 ppt for 3–24 h). Brine treatments (30 ppt) also required less time to cause 100% mortality for eight taxa compared with treatments using 34 ppt seawater. Based on these experiments and published data, we present treatment strategies for the ballast tank biota often associated with NOBOB vessels entering the Great Lakes region. We estimate the lethal dosage of brine for 95% of the species in our experiments to be 110 ppt (95% confidence interval, 85–192 ppt) when the exposure time is 1 h and 60 ppt (95% confidence interval, 48–98 ppt) when the exposure duration is 6 h or longer.
Instruments of Support at Emergency Response Planning in Urban Environment Situated at the Peripheral Area Around Industrial Facilities
Authors: Sandres G. C. , Silva C. , Chaves L. 
Published: September 2008

Abstract
Emergency Response Planning for major accidents – toxic gas leaks, fires and explosions – is a powerful tool for the chemical industry today, mainly at large-scale facilities such as oil refineries. This topic has been discussed intensively since a series of major accidents occurred at several places around the world. Organizations, industries and society have been paying close attention to this issue in order to implement the correct actions for dealing with this type of problem. In Brazil, oil refineries are often located in densely populated areas whose residents are vulnerable to major accidents, particularly because of the high-risk industrial activities conducted at these facilities.
The preparation of specific Emergency Response Plans for areas surrounding industrial complexes involves fast response systems, with the use of appropriate tools – such as Geographic Information Systems (GIS) and Risk Analyses – supporting decisions that must be taken in critical situations. Consequently, regional mapping that encompasses sets of elements constituting urban environments is very important within the External Emergency Response Planning context. Additionally, modeling critical accident scenarios that affect not only assets, but also employees and neighboring communities, portrays the actual extent of the area affected by the accidents under analysis.
By deploying the GIS as tool and modeling critical accident scenarios, georeferenced data can be generated, stored and handled, in addition to presenting the potential of spatial integrated analyses. The inclusion of geoprocessing technology, which is a vital tool for this type of planning, streamlines the integration of these data with quantitative risk analyses, constituting a powerful instrument that examines the composition of critical accident scenarios and their consequences in urban areas and outlying areas around industrial complexes. The integration of these tools is essential as a decision support system for Emergency Response Planning.
The use of support tools for dealing with emergency situations is a crucial step for dealing with major industrial accidents. The integrated use of these tools, specially the GIS and Risk Analyses, offers a fresh view of this issue and the science, making approaches to this type of problem more representative. Above all, it examines and quantifies analyses of urban environments around outlying industrial areas, fostering the development of integrated actions that help mitigate widespread impacts caused by industrial activities.
Gas Shut-off Treatment in Oil Carbonate Reservoirs in Saudi Arabia
Authors: Al-Dhafeeri A. M. , Nasr-El-Din H. A. , Al-Mubarak H. K. , Al-Ghamdi J. 
Published: September 2008

Abstract
Gas coning or channeling is a serious problem in many oil fields. It can reduce oil production significantly. Therefore, it is important to minimize excessive gas production. Production at high gas/oil ratio is a problem, which occurs because of the high gas mobility in the formation. Gels and foams have often been used to reduce gas movement into the wellbore of oil wells.
Oil production from an oil producer in a carbonate reservoir declined due to excessive gas production. A detailed diagnostic work was conducted to determine the source and entry of gases into this well. In addition, several gelling systems were examined in the laboratory as a means for gas shut-off in this well.
The results of several logs identified two zones for gas production. The first zone 6,000-6,500 ft is responsible for 80% of the gases produced from well A. Another zone, 7,200 – 7,400 ft is responsible for the remaining gases. Several chemical means were evaluated for total shut-off of these two zones. These systems were compatible with formation brines. The gelation time can be controlled by varying the cross-linker concentration, or by injecting a preflush to cool down the formation. A surfactant system with a source of calcium was evaluated to be used for gas shutoff purpose. This system produced a precipitate that can be removed by toluene and other hydrocarbons.
Field Case Histories Demonstrating the Critical Roles Played by Multiphase Flow Models in Appropriate Production Log Interpretation
Authors: Ouyang Liang-Biao , Suthichoti Polpipat 
Published: September 2008

Abstract
Production logging (PLT) has been routinely practiced in oil and gas industry to estimate oil, water, and/or gas production profile, determine fluid entry or exit location and amount along perforation interval(s), and detect major oil/gas/water producing layers. Through successful PLT surveys and appropriate interpretation, we may also identify thief zones and high perm channels, locate injected fluid breakthrough, monitor fluid front movements, detect crossflow and fluid migration, assist in reservoir simulation studies, etc.
After a PLT is run, subsequent workover is routinely performed aiming at reducing water production while maintain or even increase oil and/or gas production from the well. Unfortunately, mixing results have been obtained through workover operations designed based on PLT, due to poor logging procedure, unreasonable PL tool selection, poorly executed surveys, inappropriate interpretation, etc.
With the existence of two or three phase flow in a well, the interpretation of production logs becomes critical for achieving successful assessment of major oil, water and gas entries and thus a successful workover operation. Under most circumstances, an appropriate interpretation of production logs relies heavily on the selection of a reasonable multiphase flow model to correctly capture complex multiphase flow features in the wellbore.
In this paper, major flow characteristics of multiphase flow in a wellbore will first be described. Different correlations and mechanistic models to describe multiphase fluid flow will then be introduced; the pros and cons of correlation/model will be highlighted. Impacts of multiphase flow models on interpretation results of production logs will be investigated.
Several field case histories will be discussed in detail to illustrate the critical roles played by multiphase flow models in production log interpretation. For each field case history, the background information of well production, reservoir sands, production logging survey and interpretation, workover efforts and results, and so on, will be included. PLT interpretation based on selected multiphase flow models will be shown and compared with workover results.
Analysis of Reservoir Performance of the Messoyakha Gas Hydrate Reservoir
Authors: Grover Tarun , Moridis George J. , Holditch Stephen A. 
Published: September 2008

Abstract
The Messoyakha Gas Field is located in Siberian permafrost. The field has been described as a free gas zone, overlaid by hydrate layer and underlain by an aquifer of unknown strength. The field was put on production in 1970 and has produced intermittently since then. Some characteristic observations were increase in average reservoir pressure during shut-in, perforation blocking due hydrate formation and no change in gas-water contact. It is believed the increase in reservoir pressure was caused by the hydrate layer dissociation, rather than aquifer influx. The objective of this study is to use numerical model to analyze the observed production data from the Messoyakha field. In this study, a range of single-well 2D cross-sectional models representative of Messoyakha have been developed using Tough + Hydrate reservoir simulator. The simulation results were analyzed and compared with various field observations. Further, we have done a parametric study of reservoir properties of hydrate capped gas reservoir. We have used Tough + Hydrate to simulate the observed gas production and reservoir pressure data at Messoyakha. We simulated various scenarios that help to explain the field behavior. We have evaluated the effect of various reservoir parameters on gas recovery from hydrates. Our work should be beneficial to others who are investigating how to produce gas from hydrate capped gas reservoir.We were able to generate results that are very similar to the reported flow rates and pressure behavior in Messoyakha Field. The value of absolute permeability in the hydrate layer and the lower free gas layer substantially affects the continued dissociation of hydrates during shut-down. We also modeled the formation of secondary hydrates near the wellbore that can cause the reduced gas flow rates. The important parameters affecting the gas production are the formation permeability in the gas layer, the effective gas vertical permeability in hydrate layer, the location of perforations, and gas hydrate saturation. We have described various scenarios which are beneficial as well as detrimental in producing gas from hydrate capped gas reservoirs. We have also listed various parameters that should be carefully measured for accurate modeling work.
Well-Included Flowbased Grid Generation for Heterogeneous Reservoirs
Authors: Gherabati S. A. , Dabir B. , Hesami A. 
Published: September 2008

Abstract
Fine grid geocellular reservoir characterizations often include detailed description of geological and geometric complexity. Since this volume of details can not be handled by commercial reservoir simulators, some degree of coarsening is necessary. The fundamental agenda in coarse grid generation includes development of finer grids in regions with higher flow. Available methods in literature suffer from draw back of inability to consider both the well and geological features which mostly affect the flow response. This study introduces a new method of grid coarsening (flow based) procedure. The procedure encompasses tracing streamline from boundary to the well, monitoring velocity trend along streamline to identify high flow region and selection of appropriate points on streamlines as grid nodes. Differentiating the analytical equation of the streamline path results in developing velocity vectors and adding them up will yield a new term called cumulative velocity. Using this term, the grid points are easily identified which after implementation of Delaunay triangulation and Laplacian smoothing algorithms the main CVFE (Control Volume Finite Element) grid is produced. In addition, a robust up-scaling technique was used to calculate the tensor of permeability.
Flux-continuous finite volume scheme was used to solve the associated flow equation in the coarse block. The generated grid pattern is finer in high flow regions and can successfully adapt itself based on type of geological features presented.
Pressure was the main criteria for comparison the results of this study with those of Cartesian coarse grid. The results indicated that the response of the model with coarse grids (flow based) is more consistent with a fine model. The major advantage of the introduced method is its capability in handling the geological features within the grid. It is worthy to mention that the positioning of the well and adjustment of the required refinements around it are done automatically.
A Correlation of the Interfacial Tension between Supercritical Phase CO2 and Equilibrium Brines as a Function of Salinity, Temperature and Pressure
Authors: Bennion D. Brant , Bachu Stefan 
Published: September 2008

Abstract
The modeling of CO2 sequestration in saline aquifers is becoming increasingly important as this method emerges as the prime technology available for the disposal of large volumes of anthropogenically-generated CO2, thus reducing atmospheric CO2 emissions. The interfacial tension between the saline brine in the aquifer and the injected CO2 phase has a strong effect on the capillary pressure and relative permeability characteristics of the CO2-brine displacement, and proper understanding of the IFT level is necessary for accurate modeling and evaluation of such a process. This paper provides a summary of 168 brine-CO2 interfacial tension measurements conducted using a drop pendant interfacial tension apparatus at temperatures ranging from 41 to 125 °C, pressures from 2,000 to 27,000 kPag and salinities from 0 ppm (distilled water) to over 334,000 ppm. The dataset was regressed to develop an empirical correlation to predict the brine-CO2 IFT over the range of conditions evaluated in this work. The correlation, including temperature, pressure and salinity dependence, fits the measured data with an overall regression coefficient in excess of 0.94. In addition, a very strong relationship was found between computed gas-water ratio (dissolved CO2) and interfacial tension. An additional correlation was developed to model this effect, also with a high regression coefficient of 0.92. Since the gas-water ratio is a much easier parameter to measure than IFT, this provides a rapid and inexpensive method to estimate in-situ IFT from available or CO2 solubility data.
Determining Environmental Tradeoffs Associated with Low Impact Drilling Systems
Authors: Haut Richard C. , Burnett David , Rogers John , Williams Tom 
Published: September 2008

ABSTRACTAn environmental scorecard is being developed to determine the tradeoffs associated with implementing low impact drilling technology in environmentally sensitive areas. The scorecard will assess drilling operations and technologies with respect to air, site, water and biodiversity issues. Low environmental impact operations will reduce the environmental footprint of operations by the adoption of new methods to use in (1) getting materials to and from the rig site (site access), (2) reducing the rig site area, (3) using alternative drilling rig power management systems, and (4) adopting waste management at the rig site.The scorecard enables a dialog to be established and maintained among all interested, concerned and affected stakeholders. In this manner, the oil and gas industry has a new way of seeing itself within the larger network.The scorecard presented in the paper provides the means to demonstrate the connectivity between energy production and the affected ecosystem.The Houston Advanced Research Center (HARC) and Texas A&M University have been leading an industry consortium effort to investigate the development of low impact drilling systems.The work originated in 2005 and funding was obtained by the U.S. Department of Energy for 2006 through 2008.The goal of the low impact drilling systems project is to reduce the environmental impact of rig operations through integration of low-impact site access and site operations. The paper will discuss the scorecard that is being developed. The scorecard methodology presents an ecological understanding of the tradeoffs associated with producing energy. The EFD scorecard will be developed in detail for a coastal margin ecosystem and the methodology will be documented to enable the scorecard to be replicated at other ecosystems wherever reservoirs are produced. This scorecard methodology is being developed through a series of workshops being held with ecologists, botanists, wildlife management experts and others in addition to oil and gas industry experts.
Modeling of Drilling Fluid Losses in Naturally Fractured Formations
Authors: Majidi R. , Miska S. Z. , Yu M. , Thompson L. G. , Zhang J. 
Published: September 2008

Abstract
Significant mud losses often occur while drilling in fractured formations. Severe problems arise when drilling fluids invade high permeability conductive fractures that the well path intercepts. The industry has recently started to monitor mud loses in order to identify the fractures and characterize them. Methodologies are available to characterize the geometry and conductivity of the fractures by quantitative analysis of field measurements. These methodologies are mainly based on mathematical models that describe the physical phenomenon and the mechanism under which the flow within the fractures takes place. Once the models are provided one can look for causes of the problem and methods to minimize it.
This paper presents a new model for mud loss of non-Newtonian drilling fluids into naturally fractured formations. Flow of Yield-Power-Law (Herschel-Bulkley) fluids has been coupled with Newtonian reservoir fluid in a single fracture. The governing equations are derived based on principles of conservation of mass and linear momentum for drilling fluid and pressure diffusion for reservoir fluid. Results are obtained based on semi-numerical solutions and plotted in terms of mud loss volumes versus time. The results demonstrate how rheology of the drilling fluid and formation fluid properties can influence mud losses. The relative contributions of both drilling and reservoir fluids is determined and compared.
This model allows for predicting fluid losses for a given drilling fluid, formation fluid and operational conditions. Conversely, one can evaluate hydraulic aperture of the fractures by continuously monitoring mud losses and finding the best fit of field measurements of mud loss to the model. Field data are used to demonstrate the practical application of the proposed technique.
The proposed model is valuable for drilling operations because it can help in minimizing the loss of expensive drilling fluids through optimization of drilling fluid rheological properties and selecting appropriate lost circulation materials. The model also benefits production operations by minimizing formation damage. In addition, well completion schemes can be optimized based on the improved knowledge of the near-wellbore fracture characteristics.
Discussion on Formation Fluid Density Measurements and Their Applications
Authors: Godefroy Sophie , Zuo Julian , Fujisawa Go , O'Keefe Michael , Ardila Mario , Cañas Jesus , de Santo Ilaria , Cig Koksal 
Published: September 2008

Abstract
Knowledge of formation fluid density is necessary for a variety of applications. It provides information on pressure gradient, zonal compartmentalization, transition zone characterization, thin beds analysis, and other reservoir qualities. It also contributes to estimates of the commercial value of the produced fluid and is a critical parameter used in modeling of the reservoir fluids through the equation of state (EOS) to obtain a better representation of fluid Pressure/Volume/Temperature (PVT) properties. Various techniques exist today for the measurement of formation fluid density. These measurements can be taken either at surface on captured fluid samples or downhole in real time using formation tester tools. The different techniques include laboratory PVT analysis of a fluid sample brought to surface, pressure gradients, downhole optical spectroscopy, and, recently developed, density measurements with the in-situ densimeter, which determines density by measuring the resonance characteristics of a vibrating object immersed in the fluid.
Although PVT analyses have excellent accuracy, downhole measurements have an advantage over surface measurements as they provide in-situ measurements under reservoir conditions without depending on the quality of the fluid from the sample bottle and sample transfer. They also allow better reservoir characterization without the need for an extensive sampling program. Pressure gradient surveys have been successfully used for decades to provide density measurements of the formation fluids. Although the measurement depends on the accuracy of both pressure measurement and depth, it provides density unaffected by flowline condition of formation testers and mud filtrate contamination. Downhole flowline sensors, such as spectroscopic sensors and vibrating rods, have the advantage of providing density measurements of the fluid itself rather than relying on other parameters such as depth, but they are sensitive to flowline conditions. Whereas the estimation of density from the spectroscopic method relies on an empirical model that cannot be used in every condition, the vibrating rod in-situ density sensor gives a direct physical measurement and is thus the preferred method of measurement whenever available.