bluuebunny/crossref_metadata_2025 huggingface dataset:
GERAÇÃO DO FATOR TOPOGRÁFICO (LS) EMBACIA HIDROGRÁFICA: ANÁLISE DA EXTENSÃO DE VERTENTES
Authors: Pinheiro Leandro de Souza , Pereira Thiago Torres Costa , Rodrigues Rafael de Ávila , Jonas Gabriela Alves , Miazaki Angela Silva , Silva Venâncio Campos
Published: October 2015

A erosão laminar, devido a sua característica peculiar, é dificilmente detectada por grande parte da população,
principalmente nos estágios iniciais, havendo assim a necessidade do estabelecimento de práticas corretas de
conservação do solo. A Equação Universal de Perda de Solo (EUPS) busca estimar a perda de solo pela erosão
laminar, considerando os fatores condicionantes da erosão. Contudo, existem fatores limitantes, inerentes da
busca pela aproximação com a realidade, pois, a EUPS não considera a geometria das vertentes e aborda
parcialmente a questão da extensão das vertentes, de grande influência no processo erosivo hídrico de
superfície. Desta forma, o objetivo principal desta pesquisa foi aplicar sistemática de obtenção dos dados de
comprimento de vertentes(Fator L), considerando como a dinâmica do escoamento superficial interfere nos
resultados obtidos com a Equação Universal de Perda de Solo. Como área de estudo, foi selecionada uma
bacia hidrográfica de um canal de segunda ordem, que banha a Floresta Escola do Instituto Hidroex em Frutal
(MG). Os resultados obtidos indicaram que o Fator L influenciou sensivelmente nos dados, a técnica de
obtenção dos dados de extensão de vertentes mostrou-se adequada, apresentando valores diferenciados do
Fator LS (Fator Topográfico) ao longo da vertente, bem como a menor generalização dos dados.
CARACTERIZAÇÃO DAS VOÇOROCAS NA BR 174: TRECHO MANAUS – PRESIDENTE FIGUEIREDO (AMAZONAS)
Authors: Carvalho Daniela Paiva , Molinari Deivison Carvalho
Published: October 2015

O trabalho teve como objetivo realizar caracterização das voçorocas ao longo da BR 174, no trecho que
compreende entre Manaus e a sede do município de Presidente Figueiredo. Utilizou-se a seguinte
metodologia: primeiramente, a caracterização das formações geológicas; identificação dos tipos litológicos,
geológico e geomorfológico com localização por meiode GPS de navegação e bússola bruton. Os resultados
encontrados na primeira coleta permitem afirmar que a totalidade das voçorocas encontram-se no trecho
compreendido entre os km 0 e 82, e que das 31 voçorocas cadastradas em trabalhos anteriores, 7 foram
recuperadas pelo Departamento Nacional de Infraestrutura e Transporte (DNIT). As incisões cadastradas
encontram-se entre o contato (vertente-vale-igarapés), sendo este último em forma de “U”, algumas estão
estáveis devido contenções realizadas por meio de aterramento, plantio de grama (capim-gordura). Durante a
caracterização verificou-se que através de cortes expostos (taludes) na estrada, há presença de crostas
lateríticas ou canga laterítica. A presença de áreas institucionais (órgãos públicos federais e estaduais),
comerciais e serviços, propriedades particulares e construção de moradias próximas à saída da cidade de
Manaus também são significativas no que diz respeito ao uso do solo.
VARIAÇÃO LONGITUDINAL DOS PARÂMETROS ESTATÍSTICOS GRANULOMETRICOS NOS SEDIMENTOS DE FUNDO NO RIO MARRECAS, REGIÃO SUDOESTE DO PARANÁ
Authors: Da Luz Constantino Eleuthério , Fernandez Oscar Vicente Quinonez
Published: October 2015

O artigo trata sobre a variação longitudinal das características texturais dos sedimentos de fundo no rio
Marrecas, localizado na região Sudoeste do Paraná. A totalidade da bacia do rio Marrecas (858,52 km
2
) esta
inserida em terrenos de idade cretácea formada por rochas basálticas da Formação Serra Geral que formam
planaltos caracterizados por dissecação média e alta, topos alongados e, vertentes convexas e retilíneas. A
coleta de sedimentos de fundo foi executada entre dezembro de 2009 e janeiro de 2010 com amostrador de
mandíbula tipo “van veen” em locais situados preferentemente nas imediações dos principais afluentes eem
trechos de acesso fácil às margens do rio. Os sedimentos arenosos e rudáceos foram analisados mediante
técnicas de peneiramento e emprego de cascalhômetro. Foram calculados os seguintes parâmetros estatísticos:
diâmetro médio, mediana, grau de seleção, assimetria e curtose. Foi observada uma nítida granodecrescência
dos sedimentos de fundo em direção à jusante, alterada localmente pelo aporte de sedimentos pelos afluentes.
O grau de seleção não mostrou nenhuma tendência e variou de moderadamente a muito pobremente
selecionado A assimetria mostrou uma tendência de variação de valores positivos nos trechos superiorespara
valores negativos nos trechos inferiores, enquanto que a curtose exibiu uma passagem de valores platicúrticos
para leptocúrticos em direção à jusante. O predomínio da forma esférica nos sedimentos de fundo foi atribuído
a decomposição esferoidal do basalto.
Logros y retos de la implementación de derivados financieros estandarizados en Colombia: un análisis comparativo con México, Chile y Perú, 2008-2012
Authors: Carmona Muñoz Diana M. , Higuera Hurtado Danna , Espeleta Bayona Ana
Published: October 2015

Desde 1999 con la eliminación del sistema de banda cambiaria inicia un desarrollo significativo en el mercado de derivados colombiano (otc)5. Con las recientes crisis financieras internacionales, aumenta la necesidad de estandarizar
los productos derivados financieros con el fin de eliminar el riesgo de contraparte presentado en el mercado otc. Este artículo identifica los logros y los retos que presenta el mercado de derivados estandarizado en Colombia desde su creación en 2008 hasta 2012, analizando así años completos; se compara su evolución con la que ha venido presentado México, Chile y Perú en el mismo periodo mediante una matriz de diagnóstico para posteriormente plantear estrategias de desarrollo de mercado, desarrollo de producto, integración horizontal, acceso al mercado y desarrollo de negocio por medio de la adaptación del plan estratégico mexicano al mercado colombiano.
Palabras clave: derivados, integración horizontal, mercado estandarizado, riesgo financiero.
La investigación formativa desde la teoría de las representaciones
Authors: Padilla Beltrán José Eduardo , Rincón Caballero Diego Armando , Buitrago Duarte Laura Jimena
Published: October 2015

 En el marco de la función sustantiva de la Educación Superior, el referente de investigación formativa en la Universidad Militar Nueva Granada constituye un pilar sustancial para el desarrollo del proyecto educativo; por ende, la caracterización de este proceso en sus diferentes instancias, actores y dinámicas propicia una comprensión en torno a la necesidad de procesos formativos sustentados en aspectos representacionales. En ese sentido, este estudio emplea el enfoque cualitativo desde el método de comparación constante como propuesta metodológica para establecer referentes teóricos de la investigación formativa a nivel nacional e institucional, así como aspectos del contenido representacional de jóvenes investigadores y semilleros de investigación interpretados a través de la técnica de asociación libre. Por ello, los resultados giran en torno a una lectura de estas concepciones de la investigación formativa bajo el prisma de la teoría de las representaciones sociales, en tanto permita la comprensión del objeto de estudio desde una perspectiva psicosocial, para luego tener como conclusiones un desarrollo reflexivo acerca de supuestos metodológicos que indaguen por las prácticas, creencias y sistemas representacionales adquiridas sobre la investigación formativa en la Universidad Militar Nueva Granada
Desarrollo curricular en una comunidad de práctica – principios implementados en el ámbito del proyecto IPEC
Authors: Morais Marques Margarida , Joao Loureiro Maria , Marques Luis
Published: October 2015

En la literatura se ha reconocido la complejidad del proceso de desarrollo curricular (DC) y se ha afirmado lo deseable que puede ser la interacción entre la práctica y la investigación en Educación. El proyecto portugués IPEC buscó promover dicha articulación a través de una comunidad de práctica (CoP) online, involucrando a profesores de ciencias e investigadores en grupos de trabajo que desarrollaran módulos curriculares. En este artículo se analizan los principios orientadores de DC explorados por uno de los grupos referidos y su alineación con las orientaciones teóricas. Se realizó un estudio de caso, con observación directa (medida por una plataforma online) no participante y análisis documental, ambas sujetas a análisis de contenidos. Se constató que el CoP implementó varios principios de la literatura de la Teoría y Desarrollo Curricular: este debe ser: i) de responsabilidad descentralizada, ii) flexible y diferenciado, III) reflexivo, iv) contextualizado en un enfoque CienciaTecnología-Sociedad-Ambiente (CTSA), v) integrado, y vi) con fases interactivas. De esta forma se explora un instrumento para la validación empírica de principios de DC que emergen de la literatura. Se reconoció incluso que la vinculación de tanto profesores como investigadores en esta CoP permitió una mejor articulación entre teoría y práctica durante el CD.
El impacto de las telecomunicaciones en la educación virtual y en la consolidación de la democracia en Colombia
Authors: Arias Henao Diana Patricia
Published: October 2015

El objetivo de este artículo de reflexión consiste en estudiar el impacto que han tenido las telecomunicaciones en la educación colombiana, y cómo estos nuevos accesos virtuales a la formación y capacitación representan una plataforma importante para cerrar las brechas entre iletrados y letrados, lo que redunda de manera específica en la consolidación de la democracia.

La metodología es de tipo descriptiva en cuanto al pasado, presente y futuro de las telecomunicaciones en el campo de la educación virtual en Colombia, a través de un recorrido jurídico-político, mediante la utilización de fuentes primarias, que mostrarán la facilitación de la efectividad en los derechos fundamentales de información, comunicación y educación, independientemente del espacio donde se desarrolle el proceso de enseñanza-aprendizaje.

Así se pretende derrumbar barreras académicas y costumbres sociales, que coadyuven al ejercicio de los derechos políticos, mediante el incremento de población con capacidades de discernimiento, consolidado en herramientas adquiridas a través de las academias virtuales.
The roles of purinergic signaling in psychiatric disorders.
Authors: Cieślak Marek , Czarnecka Joanna , Roszek Katarzyna
Published: October 2015

Ecto-purines and ecto-pyrimidines are present in the extracellular space of the central nervous system (CNS). Together with P1 and P2 receptors and nucleotides metabolizing ecto-enzymes, they make signaling system involved in neurotransmission, the modulation of sensory signals, including pain stimuli conduction, and the induction of apoptosis and necrosis of the cells. Purines and pyrimidines have a dual effect: positive (neuroprotective) of nucleosides, and negative (pro-inflammatory and pro-apoptotic) of nucleotides. Adenosine-5'-triphosphate (ATP) in the CNS triggers the pro-inflammatory reactions, predominantly by activation of the P2X7 receptor, which results in production and release of pro-inflammatory cytokines. In contrast to ATP, adenosine acts generally as an anti-inflammatory agent and plays an important role in neuroprotection. Currently, it is believed that the initiation of CNS diseases, including mental disorders, is caused by any imbalance between the concentration of ATP and adenosine in the extracellular space. Genetic tests provide also the evidence for the participation of purinergic signaling in psychiatric disorders. It is believed that any action leading to the effective increase of adenosine concentration: activation of nucleotide metabolizing ecto-enzymes (mainly NTPDases - nucleoside triphosphate diphosphohydrolases), inhibition of adenosine deaminase and/or adenosine kinase activity as well as therapies using P1 receptor agonists (adenosine or its analogues) might be beneficial in therapy of psychiatric disorders.
Drivers of carbon sequestration by biomass compartment of riparian forests
Authors: Rieger I. , Kowarik I. , Cierjacks A.
Published: October 2015

Riparian forests are expected to play a crucial role in the global carbon (C) cycle but the complex mechanisms of C sequestration in forests remain poorly understood. This study used a comprehensive approach to analyze C sequestration that included the main C compartments in forests, i.e., litterfall, fine roots, and aboveground woody biomass. We aimed at modeling each of them in response to an array of environmental drivers to untangle the functioning of C sequestration by compartment. The study was conducted in a Central European riparian forest that is part of the Donau‐Auen National Park in Austria. Carbon sequestration by compartment was correlated with environmental parameters (climate, stream flow, hydrological, spatial, and forest stand parameters) using generalized linear mixed models (GLMM), and the correlations were prioritized by hierarchical partitioning. Our results suggest divergent responses of C sequestration in different ecosystem compartments under dry and wet soil conditions. In particular, dry conditions led to significantly higher C sequestration in aboveground woody biomass (larger distance to the low groundwater table), whereas wetter conditions fostered C sequestration in fine‐root (smaller magnitude of fluctuation in the groundwater table) and leaf biomass (smaller distance to the low groundwater table). Fine roots and litterfall responded to short‐term variations in climate (mean annual temperature) and flooding parameters (duration of the low to mean Danube River water level in the previous dormant season), highlighting the pivotal role of the dynamic fine‐root and leaf biomass compartments for C uptake in forest ecosystems. Consequently, litterfall and fine roots should be considered to improve the sensitivity of C sequestration model responses to climate scenarios.
Analysis of Targeted Bit Speed Technology Performance While Directional Drilling at Urengoyskoe Field (Yamal, Russia)
Authors: Dubrovin Andrey , Abaltusov Nikolay , Rublev Sergey , Kiselev Evgeny , Ovchinnikov Sergey
Published: October 2015

This paper describes the basics of the Targeted Bit Speed (TBS) technology and results of its application during construction of a group of wells at Urengoyskoe field located in Yamal-Nenets Autonomous Area, Russia. It highlights the advantages of TBS technology as compared to drilling with conventional BHA with a hydraulic drilling motor. It also compares various BHA configurations incorporating the TBS system.

The Targeted Bit Speed technology is designed to improve well drilling efficiency. The TBS technology is based on a conventional bent-housing positive displacement motor (PDM) with measurement-while-drilling (MWD) tools. TBS technology delivers the same advantages as rotary-steerable systems enabling full 3D directional control with continuous drillstring rotation. In those cases when the required dogleg severity cannot be achieved with TBS technology, the system's operation can be suspended without retrieving the BHA to the surface with further directional drilling by conventional PDM orientation method.

This paper describes the results of well construction at Urengoyskoe field, where the TBS technology was used by the operator to drill S-shaped wells with a horizontal displacement of over 1,000m.

This paper focuses on directional control improvements, increased rate of penetration (ROP) and rotary drilling share achieved by the new system.

Information provided in the paper applies to the first wells drilled in West Siberia by the TBS method.
Well Completion Selection to Increase the Efficiency of Contact Reserves Development on Example of Van-Yoganskoye Field
Authors: Kuvakina M. , Makarov Y. , Zhuravlev O.
Published: October 2015

The increase of oil production in Russia at present time and in nearest future is connected with commissioning of the largest oil fields with contact deposits. Oil and gas companies are primarily carrying out development of such deposits with the use of a system of horizontal wells. Horizontal wells let increase contact area of a reservoir with a well, and also increase production rates, as well as increase oil recovery factor (ORF) in the whole field. In some cases, the pre-emptive use of horizontal wells is due not only to technological reasons, but also to the economic ones (off-shore projects, remote locations). Despite significant development of drilling technologies (currently it is possible to drill wells with large step out and the sinking of a large reservoir), there is still quite a wide range of issues related to the construction and completion of horizontal wells. These issues include control of sand production, using of casing packers in layouts, as well as the selection and proper use of flow control units for development of fields with contact deposits, and choice of systems for monitoring of work of horizontal wells.

This article describes a procedure and subsequent justification of the choice of a well completion system for increasing efficiency of contact deposit output on the example of Van-Yoganskoe oilfield.
Solutions for Drilling Efficiency Improvment in Extreme Geological Conditions of Timano-Pechora Region
Authors: Kamatov Kamal A. , Buslaev Georgy V.
Published: October 2015

The main goal of this paper is conducting of comparative analysis of geological drilling environment and currently used downhole assemblies and tools performance for directional wells construction. Identification of problems while drilling, based on this analysis, should help operators and drilling companies within the region to plan drilling operations more properly, therefore improving drilling and economical efficiency of well constructing in hard geological conditions of Timano-Pechora oil and gas province.

Combination of available surface and downhole data allowed to identify main drilling performance limiter, that being ineffective bit-rock interaction during both rotating and sliding modes of drilling. In order to address this problem, several possible optimization techniques are highlighted, including introduction of new drill bits designs and drilling parameters adjustment, along with development of new downhole tool for better weight transfer from surface to bottomhole in both sliding and rotation modes.

The analysis includes geological description of rocks drilled based on wireline and mudlogging data; drill bits performance and dull grading review; borehole drag value estimation; physic-mathematical model of drilling BHA with weight-to-bit applying tool.
A Cross Link Polymer Sealant for Curing Severe Lost Circulation Events in Fractured Limestone Formations
Authors: Soliman Ahmed Hussein , Fathallah Mohamad Omar , Tobeh Samir M. , Al-Oqab Mohammad S. , Godara Vijay K.
Published: October 2015

Preventing and curing fluid losses in limestone formations is one of the most challenging loss situations to prevent and control. Loss zones are unpredictable, due to large vugular zones and extended and connected fracture structures. Often these limestone intervals are depleted reservoirs. Typically, calcium carbonate pills containing various size distributions are part of the lost circulation armory in reservoir sections. However, results are highly variable and not suitable for large-scale losses. This is distinguished for those situations with the most-severe lost circulation, where chemical sealants may be more applicable than treatments by plugging particles.

The paper discusses about use of a cross-linking polymer fluid treatment that enables operators to cure lost circulation zones in many different applications, providing distinct operational and economic advantages over conventional reactive and temperature activated methods.

The paper discusses the customization of the polymer fluid to have specific thickening or setting time so this loss circulation fluid can be pumped through the existing bottomhole assembly (bit nozzle size greater than 14/32nd) without losing rig time associated with tripping and mixing conventional loss circulation material treatments (LCM). The paper discusses the execution procedures and cautions to be followed to improve cross-link LCM plug placement as well as chances to arrest losses.

Due to biodegradable nature of organic cross-linking polymer plugs, it was used in sensitive reservoirs with minimal effect on the formation. The cross-linked plug or pill, with time and temperature, will break back to a fluid state and may be produced back and circulated from the wellbore.

The discussions in this paper will further reveal the workings and applicability of cross-link polymer fluid to lower costs for drilling fluids, cementing and casing design.
Increasing Productivity of Tight-Gas Wells by More Than 30% with Integrated Approach to Well Construction and Stimulation: Case Study
Authors: Zharikov M. G. , Yaskin I. A. , Ablaev A. , Yudin A. , Zaichenko D. , Tyutikov S. , Mikhaltseva I. , Dobrohleb P. , Sullagaev N.
Published: October 2015

E&P operating companies starting develop deeper production intervals with poorer formation properties due to depletion of the upper productive layers. This is a global trend worldwide. In connection with this it is very critical to optimize well construction and at the same time increase productivity of wells.

Purpose to this work was to increase the productivity of six deviated gas condensate wells drilled for the achimov tight-gas deposits of the Urengoy gas condensate field. Integrated approach to well construction, completion and two-stage stimulation as well as the other technologies were used In order to achieve high production objectives.

Because of the complex geological conditions of the achimov formation associated with the presence of abnormal pressure, narrow driling window, construction and completion of wells was associated with the risk of complications and emergencies.

The paper describes an integrated project approach to planning, construction and the stimulation of the six wells in low permeable gas-condensate formation.

The following technologies had been used during the wells construction: improved design of well completion (retrievable packer, the use of "floating" of the sealing arrangement, the use of the landing nipple below the packer to be able to cut off the producing formation, the use of premium gastight connections). Expanded set of logging (standard logging, NMR (Nuclear Magnetic Resonance), cross-dipole acoustic measurements), a special thee component cement slurry, fracturing technology with high conductive channels, coil tubing service and drilling pipes make up.

Due to integrated approach and new technology involved in well construction and completion of the six-deviated wells, construction time reduced and wells productivity increased by 30%.
Characterisation of Formation Damage Systems from Laboratory Coreflood Pressure Measurements
Authors: Vaz Alexandre Servulo , Maffra Daniel , Carageorgos Themis , Bedrikovetsky Pavel
Published: October 2015

During reactive flows in porous media with precipitation of a solid chemical reaction product, the permeability reduction occurs. The mathematical model for reactive flow in porous media formulated contains two empirical parameters – the kinetics rate coefficient, determining the reaction rate along with reagent's concentrations, and the formation damage coefficient, reflecting the permeability reduction due to the solid precipitation. These parameters are determined from the laboratory coreflood tests with commingled injection of reacting fluids. A routine laboratory method determines the kinetics rate coefficient from expensive and cumbersome reagent concentration at the core effluent; then, the formation damage coefficient is calculated from inexpensive and simple pressure drop measurements. In the current paper, a laboratory method for determining both coefficients from pressure measurements only is developed. The method utilises pressure measurements at the core inlet, effluent and some intermediate core port during commingled quasi steady state flow of incompatible fluids. The data treatment is based on the analytical model for one-dimensional commingled flow of reacting fluids. The formulae for determining the model coefficients from pressure measurements are derived. The intervals for inverse solution existence, uniqueness and stability are established. Good agreement between the model constants as determined by the routine and three-point-pressure methods validates the proposed method.
Uranium Wells: The Proper Selection of Drilling Mud and Completion Fluid Has Changed All the Rules of the Game
Authors: Arthur Gumarov , Akhat Kenjebayev , Denis Verte , Andrey Kharitonov
Published: October 2015

In Southern Kazakhstan, uranium ore is produced by the in-situ leaching (ISL) method. One of the uranium companies, which is producing in this manner experienced difficulties in attempting to increase yield when using bentonite-polymer mud and sodium hypochlorite for removing the filter cake. The company had additional objectives that included increased production cycle time and optimization of drilling technology to reduce well construction time.

The design of a typical well is represented by a vertical shaft 215.9 mm in diameter and up to 500 m deep. The well is cased by plastic pipes with a filter lining in the pay zone interval. Bottomhole temperature is in the 25–28°C range.

A three-stage concept has been proposed to complete these tasks: the use of inhibiting polyacrylamide (PAA)-based mud on the upper nonproductive intervals and a specialized mud system designed for completion of productive horizons, which includes only acid-soluble and biodegradable components. The final stage involves treating the reservoir with a filter cake removal system. Instead of sodium hypochlorite, an organic product has been proposed for the removal of the filter cake, exhibiting many advantages, such as increasing the reaction time for acid formation, deep penetration into the near-wellbore region, and guaranteed treatment of the entire interval, unlike conventional acids, which react instantaneously and are; therefore, inefficient in horizontal intervals.

These technologies were successfully applied and have provided a number of benefits to the customer, including an increase in well productivity by 20% as compared to the adjacent wells and up to a 10-fold yield increase in wells with depleted reservoirs. Time to reaching the design yield decreased on average by 30% while reducing the total well commissioning time by an average of 10%.

This article introduces some aspects of these technologies and the results of their application.
Fracturing Considerations in Mid Permeability Gas Condensate Formations
Authors: Butula K. K. , Yudin A. , Magdeyev I. , Chernyak V. , Samoilov M.
Published: October 2015

Hydraulic fracturing can be widely used for stimulation of gas condensate reservoirs not only in order to improve the Productivity Index (PI) of the well, but also to minimize the condensate banking effect and maximize recovery, therefore ultimate impact the economic success of the production enhancement operations.

Understanding the parameters affecting adequate propped fracture geometry is critical to the process. While none or limited influence can be exercised on the hydraulic fracture geometry from the reservoir side, the fracturing materials and the pumping technology at large, now on the disposition to the frac design engineer have ever been improving and will define the level of achievement.

The general statement valid for mid perm reservoirs of high pore pressure and relatively high reservoir temperature, that it is very important to create a fairly long and clean, conductive propped fractures is not sufficient, in reservoirs where condensate banking represent a potentially important pressure loss.

To counter the effects caused by pressure depletion below dew point that are resulting in multiphase flow and condensate bank creation in the reservoir, maximum conductivity fractures are designed. Further, depending on the drawdown and induced flow rate to the wellbore, non-Darcy effects, flow convergence and proppant damage can be potentially encountered; hence, fractures designed under the concept of "maximizing conductivity" will additionally decrease the well productivity decline.

The analysis presented in the paper was based on a combination of data obtained from field measurements, analytical calculation and numerical simulations, modeling in all details the key processes defining the productivity gas condensate reservoir. The first results obtained indicate that the placement of extremely conductive fractures has a definite advantage in both productivity as well as in recovery of liquid hydrocarbons.

To conclude – it can not be overemphasized that ensuring good conductive fractures that will ensure minimum pressure drop from multiphase, or non-Darcy flow is critical. Excellent wellbore connectivity by wide and conductive near wellbore fracture paths and maximizing inflow area and minimizing convergence flow effect is not to be underestimated too. The fracture design has to ensure this environment in the initial production phase as well as in years to come when reservoir pressure drop is expected and higher effective stress, proppant crush, fines migration and embedment, are placing additional strain on maintaining the fracture conductivity.
Unified Method for the Gas Condensate Field Model History Matching and Prognosis Calculations
Authors: Filippova J , Turbina T
Published: October 2015

The conversion technique for fluids produced on gas condensate field and passed through the gas treatment unit is proposed.

By proposed recalculation it is possible to transform data of produced gas volume and condensate mass to data of daily production both in volume and in mass.

Fluid model data transmission is proposed with the separation to the invariant groups of "dry gas" and "∑ C5+". With the help of data obtained from supervisory composition determination it is possible to track alteration in the "dry components" contribution supplied by the gas and condensate, as well as similar ratio of the ∑C5+ components group.

Taking the designed methodology into consideration it is possible to determine the daily volumes of "dry gas" and "∑C5+" in the gas treatment unit. Finally, according to the obtained results, produced fluids data can be matched with the data obtained from the simulation model adaptation.
Tight Gas Achimov Formation Evaluation and Sampling with Wireline Logging Tools: Advanced Approaches and Technologies
Authors: Novikov S. , Weinheber P. , Charupa M. , Ezersky D. , Rudenko D. , Mikhaltseva I. , Danilova D. , Mukminov I. , Snokhin A. , Tikhomirov I.
Published: October 2015

The Yamal region of Western Siberia holds enormous reserves of gas and condensate across many geologic layers including the Achimov deposits of the Late Jurassic and Early Cretaceous. The Achimov however, is among the most challenging layers in the Yamal area with deep bedding, very low permeability, thin laminations and abnormally high reservoir pressures that all greatly complicate the appraisal and production of hydrocarbons. In this regard, accurate formation evaluation is essential to ensure efficient and economically reasonable methods of production. Modern methods of openhole logging, including NMR, acoustic and wireline formation testers (WFT) provide advanced information about the formation and can aid in the most efficient development.

In this article we present the results of advanced methods of openhole logging that provides greater understanding of the characteristics of the Achimov reservoir. Special NMR measurements were used to estimate the residual fluid saturation which was confirmed with WFT tools designed for downhole fluid analysis and sampling. We also show how to overcome the negative impact of supercharging on measurements of formation pressure in the Achimov formations and the necessity of carrying out such measurements to validate the hydrodynamic reservoir model. To understand the validity of the samples acquired downhole a simulation was carried out further showing the range of possible variations of the basic PVT properties of hydrocarbons during the sampling.

The results of advanced acoustic logging allows to estimate the anisotropy of the mechanical properties of the Achimov layers. The use of the data allowed us to model the fractures resulting from hydraulic stimulation and showed significant differences in the geometric characteristics of the fracture between wells and explains why the lower section of the Achimov are often depleted with respect to the upper sections.
Current Results of Overlooked Targets Identification in the Fields of the Orenburg Region
Authors: Shakirov V. A. , Deryushev D. E. , Ivanov M. A. , Sereda I. A.
Published: October 2015

The Orenburg oil region is one of the oldest regions of the Volga-Ural oil and gas province. The story of the field discoveries in the Orenburg region starts from the end of 30s of the twentieth century. By now the explored stock of large and easy-to-recover deposits is nearly depleted. The production has gradually led to the depletion of the existing deposits, and the replacement of oil producer resource base has become necessary.
The Chernyshev Swell: Supertrap or Waste Zone?
Authors: Sobornov K. O. , Danilov V. N.
Published: October 2015

Several years ago the Chernyshev swell was regarded as one of the most promising areas for petroleum exploration in the Timan Pechora basin. This was mainly due to an outcome of drilling of a 1-Vorgamusur well which targeted a new exploration play related to a subthrust zone. The well encountered an oil zone which yielded an uncontrollable oil blowout. Consequently a serious interest of oil and gas companies aroused. They rushed to secure prospective acreage on the newly established trend. Since then significant exploration efforts, including new seismic acquisition and drilling of several wells, have failed to deliver commercial volumes of hydrocarbons. As a result, prospectivity of the area has been downgraded and much of the exploration acreage was relinquished. The failure was explained mainly with poor qualities of reservoirs and unfavorable preservation conditions related to intense faulting resulting in breaching of seals.

A critical review of G&G data suggest that the unsatisfactory outcome of the past exploration may to a large extent reflect shortcomings in the understanding of regional geology and inadequate technical solutions, rather than scarcity of oil and gas endowment of the Chernyshev swell. A reinterpretation of the regional structural geology provides vital clues for understanding the reasons of the past failures and permits the identification on new potentially high-impact opportunities.
An Optimization Algorithm for the Calculation of Phase Equilibrium for Thermo- and Hydrodynamic Modeling
Authors: Shevchenko A. V. , Tsybulin I. V. , Skalko Y. I.
Published: October 2015

Taking the possibilities of phase transition into consideration is necessary for numerical simulation of multicomponent mixtures flow. The problem of defining phase equilibrium of mixture with arbitrary amount of components, which are characteristic for hydrocarbons deposit (water, light and heavy oils, soluble gases) is viewed in this paper. It is considered that phase equilibrium conditions are set through constants of phase equilibrium. The modified problem of phase equilibrium is solved given values of molar concentration of all mixture components, its molar enthalpy and pressure. As a result, we define on what phases the mixture will segregate to, its molar fractions, compositions and temperature. The algorithm is based on minimization of Gibbs potential with usage of the ideas of logarithmic barriers method. The algorithm is verified and has been studied in detail.
Geological and Hydrodynamical Simulation with Formation Mechanical Properties Taken into Account
Authors: Bogachev K. Yu. , Eydinov D. A. , Korneva D. A. , Piskovskiy E. V. , Shaybakov A. L.
Published: October 2015

Describing changes of stress-strain state during hydrodynamic simulation is currently a problem of great importance. In this paper we consider one of possible approaches to solve coupled hydrodynamic and geomechanical problem.
Geological Models for the Implementation of Adaptive Exploration and Fast-Tracking Field Development of Oil Pools in Imilor-Istochny License Aria
Authors: Kasatkin V. , Shalamova V. , Druchin V.
Published: October 2015

New conceptual geological models of oil pools of Imilor-Istochny subsurface area (West Siberia, Surgut oil- and gas-bearing region) are proposed, this is the basis of computer realization performed in options of permanent geological 2D and 3D models. Models were created under the assumption that the complex structure of the geological features of the area - are connected to a nonpositive regional structures, multifacies genesis of productive reservoirs, a clinoform-like structure of the main oil and gas complex, the presence of zones of anomalous section of the Bazhenov Formation.

The detailed correlation of perspective deposits is created taking into account the seismic CDP-2D and 3D, while used a clinoform-like model of the Neocomian deposits, landslide genesis of the formation of reservoirs in the anomalous "Bazhenov". Built consistent structural skeleton of the field with simultaneous using of all the reference horizons, with the specified boundary of the domain of productive strata. The boundaries of the spread of productive layers, line thinning, replacement of reservoirs. the effective thickness are of the preliminary determined due to the geological interpretation of seismic data.

To justify the reservoir properties of productive beds proposed approach from the standpoint of thin-layered media.

Built new geological 2-3D models of Imilor-Istochny subsurface area (the area of simulation approx 1500 km2) include 23 productive reservoirs in Upper Jurassic and Lower Cretaceous sediments, for the first time allocated 85 oil pools. These models are used to support exploration and the "local" field development, the basis for the calculation of reserves and the implementation of design and technological documents for the development of pools. To create the models used modern mathematical approaches based on variational principle and ideas of mathematical physics implemented in computer programs Isoline, GST, Roxar, Stratatool.
Experience of 3S-technology Application for Natural Gas Processing at Gas Facilities in Russia and China
Authors: Bagirov Lev A. , Imaev Salavat Z.
Published: October 2015

Over the last decade ENGO Engineering Ltd. successfully implements supersonic separation technology (3S-technology) for natural and associated gas processing at the gas producing facilities in Russia and China. This paper describes supersonic gas separation technology main physical principles and provides detailed information about the technology application at the facilities in operation.
New Approach to the Evaluation of the Structure of Initial Reserves in Ozhginskoe Gas-Oil Field
Authors: Podnebesnykh A. V. , Baryshnikov A. V. , Kuvaldin A. P. , Stukov S. P. , Enilin A. S. , Timokhovich Yu I. , Nurov R. S.
Published: October 2015

At the present time insufficient attention is given to reserves estimation of fields on exploration and operational stages. Estimation of reserves distribution, as a rule, is made by classical approach, based on tectonic geology and generation of average reservoir properties (Orlova L.A. and the others, 2010; Gutman I.С., 1985). Under this approach risks and uncertainties of geological factors analysis is lacking. Due to this approach it is possible to correct of reserves distribution during the development and in the end it can influence on strategy of field development.

Ozhgiskoe gas-oil field is on the first stage of development and has all specific parameters: progressive production, increasing well fund, low water-cut, high rate reservoir pressure decline. Three clusters are in operation (in central and west parts of the field).

For effective development monitoring and development strategy formulation geo-technical model was created. Further to integral history matching it failed to achieve good convergence: discrepancy of gas production history and current gas-oil ratio well after well, considerable discrepancy oil production in several good wells. Using all allowed methods of history matching, it failed to history repeating (Tatarinov I.А. and the others, 2012).

Therefore by the example of Ozhgiskoe gas-oil field ZAO «UNS» new procedure of IOIP estimation was realized with risks and uncertainties analysis. This procedure allows to take strategic decisions when placing new objects in operation. Results of work are interesting for specialists, which are concerned of uncertainties estimation and risks management during new fields development.
Simulation of Hydrodynamic Conditions of Bottom-Hole Zone of Well to Test a Capsulated Corrosion - Scale Inhibitor
Authors: Aygiz Khazhiev , Alexander Faresov
Published: October 2015

This article describes a new approach to laboratory tests to determine the period of effective operation of a capsulated corrosion - scale inhibitor in the course of downhole oil production. The urgency of this method lies in the laboratory simulation of service conditions for a well with certain operating practices and also in determination of the period of effective operation of a capsulated corrosion - scale inhibitor. The effective operation of the capsulated inhibitor of complex action means its ability to be carried uniformly and in the required amount out from the well together with the associated produced fluid and its ability to provide the necessary protection against corrosion for downhole equipment during the whole period of production.

The below described technology can be applied, in our opinion, to protect the downhole equipment against corrosion by loading of the capsulated corrosion - scale inhibitor in the zone of mechanical impurities of well fluids surge (ZMIFS). The technology of capsulated inhibitors application provides a controlled carrying out of the inhibiting component for a long period of time. In case of application of the corrosion - scale complex inhibitor, equal time periods of effective carrying out from the capsule are required for corrosion inhibitor and scale inhibitor.

We have developed a laboratory flow testing unit which allows to simulate the operating conditions of a certain well. Based on the foregoing, the experimental testing unit is a flow-type outline that includes two sections for testing. Using this testing unit one can determine the period of carrying out of one unit of capsulated corrosion inhibitor per one unit of volume of the simulated corrosive environment in order to provide more efficient protection against corrosion and scaling.

The results of laboratory tests have been used for quantitative calculations of inhibitor demand for pilot tests in the producing wells of PJSC "RN-Nyaganneftegaz."
Investigation of Effect of Suspended Solids in Extracted Fluid on Pump Performance and Development of Means for Catching them
Authors: Isaev A. A. , Takhautdinov R. Sh. , Malykhin V. I. , Sharifullin A. A.
Published: October 2015

Presence of mechanical admixtures in the form of suspended solids (SS) causes wear of a rotor surface and, particularly, elastomer.

Wear of friction surfaces leads to hydraulic head and efficiency losses of Progressing Cavity Pump (PCP) due to decrease in tightness of contact between an elastomer and a rotor.

Test bech has been designed (Fig. 1) to study the effect of wear rate on head-capacity curves of PCP unit. The bench consists of the frame 1, legs 2, tank 3, pipelines 4, drive motor 5, rod 6, shut-off valves 7 and measuring tools.
The Method of Determining the Effectiveness of Dispersant for Oil Spill Response at Icy Seas
Authors: Salnikov Aleksander V. , Gribov Grigory G.
Published: October 2015

The most efficient way to eliminate oil spills in icy seas is the way of using dispersants. However, for to-day doesn’t exist not only universal dispersants for these purposes, but also methods of determina-tion of their efficiency. Tests, which are known in world practice, in a different measure display interac-tion of water-oil mixture with a dispersant, are expensive, possess insignificant convergence and repro-ducibility, and in Russian Federation are applied restrictedly.

On the basis of the carried-out analysis of the ways of determination of efficiency of dispersants exist-ing in world practice, this work is offering the new express method of determination of efficiency of dis-persants for the ice seas developed in Ukhta State Technical University together with LLC «USTU Oil and Gas R&D Institute».

The method, offered in work, can be used for an assessment of efficiency of dispersants for elimina-tion of emergency oil spills in the icy seas of the Arctic region in the conditions of the wide range of tem-peratures and salinity of water, and can become alternative to foreign analogs.

The method possesses considerable knowledge intensity, doesn’t demand expensive equipment and highly skilled personnel, and also allows carrying out several parallel experiments.
Net Environmental Benefit Analysis in Planning of Elimination of Oil Spills
Authors: Alekseevna Natalya , Seryy Sergey Sergeevich
Published: October 2015

Intense development of oil and gas deposits on sea shelves and inner pools is one of the most powerful factors of negative impact on water environment and biological resources owing to inevitability of emergency spills of liquid hydrocarbons. Now, choice of ecologically suiting technologies and methods of oil spills liquidation in global practice based on net environmental benefit analysis (NEBA). NEBA is a process of decision making in the time of choosing methods of oil spills liquidation, which provide the less negative impact on the environment in every case. The main reason for making such an analysis is a presumption that not only oil spills but also operations for its liquidation could have negative impact on the environment. The decision of using such technologies as dispersion and burning oil on the spot is made only according to NEBA. Order of making this analysis from the point of ecological advantages of applying technologies of oil spills liquidation is presented fully and by stages and also analysis of ecological impact of using these technologies was made. The competent and timely analysis of ecological consequences of application of technologies of elimination of pollution will lead to the minimum negative impact on marine and coastal ecosystems.
Best Configuration of Horizontal and Vertical Wells for Heavy Oil Thermal Recovery from Thin Net Pay Zones
Authors: Khisamov Rais , Zaripov Azat , Shaikhutdinov Damir
Published: October 2015

Pilot projects on heavy oil production in the Republic of Tatarstan proved the efficiency of Steam Assisted Gravity Drainage (SAGD) and Cyclic Steam Stimulation (CSS) technologies for horizontal wells. This paper discusses ways of improving CSS technology and search for alternative methods of extra-viscous and heavy oil production from thin net pay zones. Various configurations of vertical wells and a single horizontal well have been considered. It has been shown that using vertical wells in combination with a horizontal well can provide a two-fold increase in ultimate oil recovery compared to CSS method. The best configuration has been identified to provide maximum recovery of heavy oil from thin pay zones. Pilot test program has been developed to test the suggested well configuration in the Ashalchy pilot area.