bluuebunny/crossref_metadata_2025_split huggingface dataset:
Legal Status Of The Caspian Sea: History And Present
Authors: Kapyshev Ardak 
Published: October 2013

At the present stage one of the unsolved problems in interstate relations of Caspian bordering countries is defining international­legal status of the Caspian Sea. It is noted in the article that this problem is not a new one at all. The history of “division” of the Caspian Sea begins in the ancient age, namely in VIII century. It is underlined that the basic stumbling block is the position of Iran on the right to use the Caspian Sea, and also occurrence of extra regional players, such as the USA, China, etc. First of all, it is connected with rich oil fields and other minerals, and also with convenient geopolitical and geostrategic position. The only way to worry out the international­legal delimitation of the Caspian Sea problem is a negotiating process. By now, despite of certain disagreements on legal status of the Caspian Sea, five Caspian bordering countries managed to achieve certain progress, admitting the possibility of applying the principle of sectorial sectioning on the Caspian Sea. Clear proof of it is the agreements on division of ground on the northern part of Caspian Sea signed between Kazakhstan, Russia and Azerbaijan. It is important that Kazakhstan, Russia, Azerbaijan and Turkmenistan clearly stated their positions and agreed to make a compromise in their official statements. More than likely, in the near future Iran will soften its position, considering its present situation and strained relations with the USA. It has been alleged that the constructive dialog already started; everything depends on the mobility, concurrency and rationality of actions of all Caspian bordering countries.
Numerical Research Of Nonlinear Vibrations Of Isotropic Viscoelastic Plates With Variable Rigidity By The Method Of Computer Simulation
Authors: Abdikarimov Rustam 
Published: October 2013

In the given work the problem about vibrations of a isotropic viscoelastic plate with variable rigidity in geometrically nonlinear statement is considered. With the help of Bubnov-about nonlinear vibrations of viscoelastic isotropic plate in geometrically nonlinear statement on Kirchhoff-Love’s kinematic hypothesis, physical dependence between. Galerkin method the problem is reduced to the decision of system of nonlinear ordinary integro-differential equations of Volterra’s type. The numerical method based on the use of quadrature formulas is applied for the decision of the received system at weakly singular kernel of Koltunov- Rzhanitsin’s. Influences of viscoelastic properties of a material, geometrical characteristics, and also dependences.
The concentration of high-sensitivity troponin I, galectin-3 and NT-proBNP substantially increase after a 60-km ultramarathon
Authors: Salvagno Gian Luca , Schena Federico , Gelati Matteo , Danese Elisa , Cervellin Gianfranco , Guidi Gian Cesare , Lippi Giuseppe 
Published: October 2013

AbstractThe leading mechanisms responsible for the most prevalent and serious cardiac injuries include myocardiocyte stretch, myocardiocyte necrosis and cardiac fibrosis, which can now be reliably mirrored by measurement of natriuretic peptides, cardiospecific troponins and galectin-3, respectively. Although a large amount of knowledge has been gathered about the behavior and clinical significance of these biomarkers in patients with cardiac disorders, less information is available on their biology in paraphysiological conditions, including high-intensity endurance exercise.The study population consisted of 18 trained athletes, who performed a 60-km ultramarathon run. Blood was collected before the run (i.e., “baseline”) and immediately after the end of the ultramarathon (“post-marathon”) for measurement of serum high-sensitivity troponin I (TnI), NT-proBNP and galectin-3.The concentration of all biomarkers measured in the post-marathon samples was remarkably increased as compared with the values obtained on baseline specimens. In particular, the median increase was 3.3 for TnI, 3.5 for NT-proBNP and 2.4 for galectin-3, respectively. The frequency of values exceeding the diagnostic threshold did not differ at baseline and after the ultramarathon for TnI (6% vs. 25%; p=0.15), instead was significantly increased for NT-proBNP (0% vs. 28%; p=0.016) and galectin-3 (0% vs. 67%; p<0.001). No significant correlation was found among the increase of any of the three biomarkers.The results of this study demonstrate that high-intensity endurance exercise is associated with biochemical abnormalities that may reflect adverse consequences on cardiac structure and biology.
Flow Analysis: A Critical Step in Completion Design and Optimization. A Case Study of Multizone Completion Designs
Authors: Pogoson Oje , Cardona Andres 
Published: September 2013

Abstract
Multizone completion systems are used worldwide as an efficient method to maximize reserves recovery. There are several assets in the deepwater Gulf of Mexico where this technology is the preferred option for optimizing drainage of multiple zones and/or reservoirs in the same well completion. However, the selection and design of these completions demand specialized evaluations of completion equipment, analysis of fluid properties and operating conditions, not only to maximize production but also to ensure the reliability of the completion system.
The scope of this study covers completion design configurations and flow analysis for a well intersecting three zones (reservoirs), using completion data, fluid and reservoir properties to evaluate expected well production and completion reliability. Four completion design options were evaluated: one x dual zone and three x triple zone completions, each with a different flow configuration.
The analysis adopted considers the entire completion system including fluid flow paths and actual dimensions of equipment and their position in relation to other equipment. The objective is to calculate the maximum production rate through a completion system based on erosion assessment, and also evaluate the pressure loss at defined production rates. Production scenario calculations were also performed at defined wellhead pressures.
Flow analysis results show that the evaluated design options each offered unique capabilities based on a set of defined completion and production constraints. Each completion design exhibits different flow capacities with pressure loss variances. Results also identified sections within the completion systems where dimensions or other physical properties of equipment can be optimized to maximize the flow of produced fluid, and minimize the potential for erosion.
This study identifies a methodology for completion design and optimization during field development planning and management. It provides valuable information and decision tools for reservoir (drawdown, flow rates, and fluid behavior conditions) production (flow rates and flow assurance) and completion engineering teams (optimized completion design, pressure, temperature and erosion parameters).
Characterizing Hydraulic Fracturing with a Tendency for Shear Stimulation Test
Authors: McClure Mark , Horne Roland 
Published: September 2013

Abstract
The classical concept of hydraulic fracturing is that a single, planar, opening mode fracture propagates through the formation. In recent years, there has been a growing consensus that natural fractures play an important role during stimulation in many settings. There is not universal agreement on the mechanisms by which natural fractures affect stimulation, and these mechanisms may vary depending on formation properties. One potentially important mechanism is shear stimulation, where increased fluid pressure induces slip and permeability enhancement on preexisting fractures. We propose a tendency for shear stimulation (TSS) test as a direct, relatively unambiguous method for determining the degree to which shear stimulation contributes to stimulation in a formation. In a TSS test, fluid is injected at a bottomhole pressure that is maintained below the minimum principal stress. Under these conditions, shear stimulation is the only possible mechanism for permeability enhancement (except perhaps thermally induced tensile fracturing). Standard pressure transient tests could be performed before and after the TSS test to estimate formation permeability. The flow rate transient during injection may also be interpreted to identify shear stimulation. Numerical simulations of shear stimulation were performed with a discrete fracture network (DFN) simulator that couples fluid flow with the stresses induced by fracture deformation. These simulations were used to qualitatively investigate how shear stimulation and fracture connectivity affect the results of a TSS test. Two specific field projects are discussed as examples of a TSS test, the Enhanced Geothermal Systems (EGS) projects at Desert Peak, Nevada and Soultz-sous-Forêts, France.
Deconvolution of Well Test Data in Lean and Rich Gas Condensate, and Volatile Oil Wells below Saturation Pressure
Authors: Ogunrewo O. , Gringarten A. C. 
Published: September 2013

Abstract
Deconvolution is a recent milestone in well test analysis which converts multirate pressure data into a single drawdown at constant rate. It yields a pressure derivative with a duration equal to the duration of the test, thus providing more pressure data to interpret than with conventional techniques; and gives access to the true radius of investigation of the test. In addition, the deconvolved derivative is free from distortions due to the pressure derivative calculation algorithm and from errors introduced by incomplete or truncated rate histories. Theoretically, deconvolution is only valid for linear systems. In practice, it is also used, with pseudo-pressures, for dry gas, and even for gas condensate and volatile oil below saturation pressure. As these systems are highly non-linear, there has been some concerns about the validity of such an approach.
This paper investigates the use of deconvolution for gas condensate and volatile oil below saturation pressure. Using compositional simulation, it applies deconvolution to different reservoir geometries using two-phase pseudo-pressures, which linearize the reservoir-fluid system by replacing the two-phase fluid below saturation pressure by a single fluid equivalent. Comparison with deconvolution using single-phase pseudo-pressure (for gas condensate) or pressure (for volatile oil) shows that the resulting deconvolved derivatives are similar, and in particular exhibit similar late time behaviours, thus justifying the simpler pseudo-pressure (resp., pressure) approach. Simulation results were verified with actual data from vertical and horizontal wells in a number of gas condensate and volatile oil reservoirs.
Investigation of Nanoparticle Adsorption during Transport in Porous Media
Authors: Zhang Tiantian , Murphy Michael , Yu Haiyang , G.Bagaria Hitesh , Yoon Ki Youl , Nielson Bethany M. , Bielawski Christopher W. , Johnston Keith P. , Huh Chun , Bryant Steven L. 
Published: September 2013

Abstract
Nanoparticles (D ∼ 5 to 50 nm) easily pass through typical pore throats in reservoirs, but physicochemical attraction between nanoparticles and pore walls may still lead to significant adsorption. We conducted an extensive series of nanoparticle transport experiments in core plugs and in columns packed with crushed sedimentary rock, systematically varying flow rate, type of nanoparticle, dispersion concentration, number and sizes of dispersion slugs, and column grain size. Effluent nanoparticle concentration histories were measured with fine resolution in time, enabling evaluation of nanoparticle adsorption in the columns during flow of dispersion and of postflushes. We also apply this analysis to transport experiments reported in the literature.
Our analysis indicates that nanoparticles undergo both reversible and irreversible adsorption. Effluent nanoparticle concentration reaches the injection concentration during slug injection, indicating the existence of an adsorption capacity. Experiments with a variety of nanoparticles and lithologies yield a wide range of adsorption capacities (from 10−7 to 10−2 g nanoparticle/g porous medium) and a wide range of proportions of reversible and irreversible adsorption. Reversible and irreversible adsorption sites are distinct and interact with nanoparticles independently of each other. The adsorption capacities are typically much less than monolayer coverage but are not an intrinsic property of the porous medium nor of the nanoparticle. Instead, they are influenced by operating conditions, i.e., increasing with larger injection concentration and smaller flow rate.
High Pressure Stimulation – Impact of Hydraulic Fracture Geometry to Unconventional Gas Appraisal and Development in Compressional Settings
Authors: Yuan Roger , Jin Liang , Zhu Changlong , Vitthal Sanjay , Xu Bin 
Published: September 2013

Abstract
For unconventional resources exploration and development, hydraulic fracture pattern, geometry and associated dimensions are critical elements in determining if the uneconomically low-permeability reservoirs can be effectively and efficiently stimulated. In principle, hydraulic fracture growth pattern is dominated by the state of stress in the subsurface, and commonly and optimally, hydraulic fractures are expected to grow vertically from deep wells and to have sufficient height growth to connect stacked hydrocarbon-bearing and horizontally more permeable reservoir packages while being contained to stay away from water-rich intervals. While the tectonic setting and in-situ stress conditions for vertical fracture development have been well studied, those for horizontal or complex fractures remain unclear or not well reported. In this paper, a case study is presented on the complex hydraulic fracture in a highly over-pressured and tectonically stressed tight gas field in the Sichuan Basin of southwest China.
During deep well hydraulic stimulation of the primary reservoirs of the Upper Triassic Xujiahe formation in the central western Sichuan Basin, difficulties are encountered in formation breakdown, injectivity establishment, proppant placement, pump equipment shut down, continuous high treating pressures, casing shear, and screen-out. These difficulties are preceded by larger-than-overburden breakdown pressures and ISIPs (Instantaneous Shut-In Pressure) during diagnostic pre-fracture injection tests, which imply that hydraulic fracture may have initiated and propagated horizontally. Different fracture monitoring techniques, however, have indicated that instead of getting purely horizontal fracture geometry, hydraulic fractures may have formed a complex network characteristic of T-shape or I-shape geometry. The main causes for such complex fracture geometry and limited fracture height are investigated and studied.
To quantitatively evaluate the fracturing performance and strategy, two classes of numerical hydraulic fracture models are undertaken. In addition to the LEFM (Linear Elastic Fracture Mechanics) based hydraulic fracture simulation, a fully-coupled finite-element based model is developed that takes into account a full suite of rock mechanical properties of sandstone and shale sequences and geological features that may limit or facilitate the fracture growth. The modeling results indicate that in addition to the typical stress control on the growth of fracture height, contrast in mechanical property and the presence of bed-parallel geological features may act as fracture baffles or barriers that prematurely arrest the vertical growth and facilitate development of horizontal fractures.
Deciding Whether to Fund Either CCS or CCUS Offshore Projects: Are We Comparing Apples and Pears in the North Sea?
Authors: Harrison Bob , Falcone Gioia 
Published: September 2013

Abstract
Recent years have seen significant funding competitions launched in Europe and in the UK that call for bidders to propose commercial demonstration projects which will bring innovation across the carbon capture and sequestration (CCS) technology chain to reduce energy system costs. The primary carbon dioxide (CO2) storage site candidates that are targeting funds are the saline aquifers and depleted oil and gas fields in the North Sea. At the time of writing, no outright winners have been announced.
These programs are open to CCS projects as well as carbon capture, utilization and storage (CCUS) projects. The former deals exclusively with greenhouse gas storage, but the latter differs by using the injected CO2 for enhanced oil recovery (EOR) before eventually being stored. Hence, there are considerable technical and commercial differences between CCS and CCUS projects, in much the same way as onshore projects face less challenges and constraints than if they were being implemented offshore.
The evaluation and selection of which offshore carbon storage projects should be funded is a tough exercise to undertake, but it becomes much more difficult if the competing projects under consideration are allowed to be CCS or CCUS, full chain or part chain, or a mixture of all of the aforementioned. Bias may arise via reliance on selection criterion such as volume of stored CO2 per unit of expenditure, which is likely to favor saline aquifer storage projects over other types, no matter how innovative or compelling they are.
The authors believe that selection committees in Brussels and London would greatly simplify their decision of which bid should be funded, and in what proportion, by separating competing projects into straightforward storage types and CO2-EOR types. Offshore experience of either project type is scarce and their relative merits are difficult to reconcile as the subsurface understanding, timeframe, economics, performance and goals of each project type are quite different.
The paper recognizes that CCS-type projects can be further subdivided into saline aquifers, with open and closed systems, and abandoned gas fields, as each have different storage limitations. Also, CCUS-type projects, which realistically only include abandoned oil fields, can be further subdivided to reflect the operational and commercial characteristics of different EOR schemes.
It is hoped that the discussion outlined in this paper will lead to easier and fairer screening criteria for offshore CCS and CCUS projects for use by governments, operators and investors alike.
Anisotropic Dispersion and Upscaling for Miscible Displacement
Authors: Adepoju Olaoluwa O. , Lake Larry W. , Johns Russel T. 
Published: September 2013

Abstract
Dispersion is the irreversible mixing that occurs during miscible displacements. Dispersion can reduce local displacement efficiency by lessening solvent peak concentration or increase volumetric sweep efficiency by spreading of the injected solvent to more of the reservoir. Dispersion is therefore an important parameter in predicting and simulating miscible displacements. The difficulty of simulating miscible displacement and understanding the effect of dispersion is also compounded by numerical dispersion, which increases the apparent dispersion in finite difference simulation models.
This paper presents an approach to estimate the total longitudinal and transverse dispersion in large-scale media using continuous solvent injection in a medium of finite thickness. The simulations are based on the experimental arrangement of Blackwell (1962) to estimate transverse dispersion, whose experimental consisted of co-injecting two miscible fluids into different sections of the medium at similar rates. Coupled with analytical solutions for two-dimensional convection dispersion equation for a continuously injected solvent we can determine longitudinal and transverse dispersivity simultaneously for the flow medium. In this manner we investigate the effects of stochastic permeability distributions and other scaling groups affecting first contact miscible simulations on dispersion.
Sensitivity analysis of dispersion in stochastic permeability fields confirms that both longitudinal and transverse dispersion are scale-dependent. Results also show that the effect of increasing autocorrelation of cell permeability in the longitudinal direction (parallel to flow) is to increase longitudinal dispersion, as solvent travels through more continuous layers, while reducing transverse dispersion. Increasing autocorrelation in the transverse direction is to reduce dispersion in both directions. This reduction is caused by equilibration of solvent concentrations in continuous sections of the reservoir resulting in reduced solute fingering and channeling.
Finally, we developed a simple procedure to use the estimated dispersivities to determine a-priori the maximum grid-block size that will maintain equivalent level of dispersion between fine-scale and upscaled coarse models. Large grid block sizes can be used for highly heterogeneous and layered reservoir models. Non-uniform coarsening (upscaling) methods were also recommended and validated for reservoir models with sets of sequential but different permeability distributions. The procedure was extended to multi-contact miscible simulations. The sweep and recovery from upscaled multi-contact miscible simulations were comparable to those of fine scale models.
Contributions to the Empowerment of Women in the Oil Industry
Authors: Hosnia Hashim S. , Capello Maria A. 
Published: September 2013

Abstract
The Society of Petroleum Engineers has taken bold and specific steps in promoting the skills, empowerment and network of female engineers, with several important initiatives, events and activities that position this Society as a pioneer in this area. The paper summarizes the initiatives of SPE in this area, being the first and most important professional society in the Oil and Gas sector to create opportunities for the networking, discussion and motivation of women with professional roles and responsibilities in the industry to move towards higher standards, conditions and leadership positions.
Three key concepts were identified in all SPE activities related to the empowerment of women that deserve a special mention: (1) the concept of inclusion, retention and empowerment of women in the workforce being a clear business necessity, (2) the recognition of the need to train the male counterparts to embrace the increased presence of women in the workforce, and (3) the implementation of guidelines for the implementation of recruitment, succession plans and promotion strategies with a gender-balanced strategy and focus.
An analysis of the characteristics of the current situation of the SPE actions in relation to the female component of the membership shows how the common denominator was found to be the industry's interest to promote the effective progression and retention of the female component towards the highest levels in technical and managerial careers, as one effective and immediate remedial action to overcome the workforce shortage and crew change challenges.