Field In Colombia Research Articles

María, de Grau, en el contexto cinematográfico colombiano: “María está rara”

In the history of film adaptations of the novel Maria (Isaacs, 1867), to experimental and iconoclastic film Maria (Grau, 1966) it is identified as belonging to the uncanonical trend or subversion and background to the position presented in the Colombian culture field. The article continues with a detailed analysis of the characteristics of narratives and stylistics to determine the semantic level in which it operates its proposal to adjust and, from print and oral records related to the film, their conditions of production, circulation and reception are studied. This analysis shows how a uncanonical position before the novel is built from multiple levels of meaning, determining their place in literary and film fields in Colombia in the 1960s and presenting new clues to understanding the place of the experimental theater in the history of Colombian cinema.

Molecular and biological characterisation of two novel pomo-like viruses associated with potato (Solanum tuberosum) fields in Colombia.

Potato is the fourth most important crop worldwide that is used as a staple food, after rice, wheat and maize. The crop can be affected by a large number of pathogens, including fungi, oomycetes, bacteria and viruses. Diseases caused by viruses are among the most important factors contributing to reduced quality and yield of the crop. Potato mop-top virus (genus Pomovirus) induces necrotic flecks in the tuber flesh and skin of potato in temperate countries. Spongospora subterranea is the vector of PMTV. Both the virus and its vector cause disease in potato. In Colombia, PMTV has been detected throughout the country together with a novel pomo-like virus in the centre (Cundinamarca and Boyacá) and south west (Nariño) of the country. We studied the molecular and biological characteristics of this novel virus. Its genome resembles those of members of the genus Pomovirus, and it is closely related to PMTV. It induces mild systemic symptoms in Nicotiana benthamiana (mosaic, branch curling), but no symptoms in N. tabacum, N. debneyi and Chenopodium amaranticolor. The proposed name for the virus is "Colombian potato soil-borne virus" (CPSbV). Additionally, another pomo-like virus was identified in Nariño. This virus induces severe systemic stem declining and mild mosaic in N. benthamiana. The tentative name "soil-borne virus 2" (SbV2) is proposed for this virus. No vectors have been identified for these viruses despite several attempts. This work focused on the characterisation of CPSbV. The risk posed by these viruses if they are introduced into new territories is discussed.

Reflexiones sobre la pertinencia de la educación en el campo de la gerontología en Colombia y en el mundo

<p>Este artículo tiene como propósito presentar un cúmulo de reflexiones sobre la pertinencia de la gerontología como carrera profesional, las cuales se sustentan en un conjunto de necesidades y aspectos que tienen resonancia a diferente escala (mundial y nacional) tales como: el envejecimiento demográfico y sus consecuencias; la transición epidemiológica; el perfil social de la población vieja; el reto de la dependencia; el rol de las personas mayores en la socialización de generaciones más jóvenes y, en la normatividad en temas relacionados con el envejecimiento y la vejez. Se concluye, con preocupación, que ante el panorama que justifica plenamente la necesidad de formar profesionales en gerontología, hoy exista una muy baja oferta de formación en pregrado en este campo en Colombia, lo cual demuestra la poca visibilización de las profundas transformaciones y consecuencias que, a mediano y largo plazo, trae el proceso de envejecimiento que actualmente vive el mundo y nuestro país.</p><p> </p>

Liderazgo informal en las organizaciones: Análisis sobre su impacto e influencia en la productividad y competitividad

La presente investigación tuvo como objetivo analizar, a partir de diversos aportes teóricos y dialógicos, las influencias e impactos del liderazgo informal en la productividad y competitividad de las organizaciones. Para lo cual, se utilizó un enfoque hermenéutico reflexivo de la investigación bibliográfica, que permitió la comprensión e interpretación de investigaciones consultadas en bibliotecas y bases de datos electrónicas de reconocimiento mundial. Además, se consultó la opinión de expertos académicos del campo administrativo en Colombia para recopilar las voces y percepciones sobre el tema. Los principales resultados evidencian que el liderazgo informal, como una dinámica propia de los grupos informales, al vincularla al factor humano de la organización, puede influir de manera positiva o negativa en la productividad y competitividad. Se concluye que la gestión administrativa de este fenómeno organizacional se convierte en una herramienta para lograr ventajas competitivas en las organizaciones a través del mejoramiento de las variables funcionales de la empresa y el establecimiento de relaciones sociales más eficientes.

Genome characterization of a Potato virus S (PVS) variant from tuber sprouts of Solanum phureja Juz. et Buk

Potato virus S (PVS) is a prevalent virus in potato fields in Colombia and the rest of the world. PVS has been classified into two separate lineages, PVSO (Ordinary) and PVSA (An- dean), which are genetically distinct. In this study, the com- plete genome sequence of a new PVS isolate (PVS_Antioquia) was obtained using High-throughput sequencing (Illumina HiSeq-2000) from tuber sprouts of Solanum phureja (var. Criolla Colombia). The PVS_Antioquia genome comprises 8,483 nt that code for six ORFs: RdRp (223 kDa), TGBp1-3 (25kDa, 12kDa, 7kDa) CP (32.3 kDa) and NABP (11 kDa) and share a high sequence identity with respect to the PVS_RVC (>95%) from Colombia, in contrast to 81 to 82% identity with respect to the PVSA and PVSO isolates from around the world. This genome information was used to design RT-qPCR primers that are specific for the Colombian PVS strains (RVC and Antioquia) which were validated in S. phureja leaf and tuber samples. These primers detected PVS in 80 and 60% of a set of fifteen leaf and tuber samples, respectively, suggesting a high incidence of this virus in the potato crops of Antioquia.

Evidence of gene flow between transgenic and non-transgenic maize in Colombia

Maize (Zea mays) is an important crop worldwide and is essential for industry. Many transgenic cultivars of maize have been developed over the years from this species, producing cultivars resistant to herbicides and insects, among other things. However, little is known about the gene f low processes that affect maize fields in Colombia, which is near the center of diversity for cultivated maize. We analyzed the gene f low phenomenon of 60 randomly chosen plots of maize, including farmer field landraces or other conventional varieties such as non-transgenic hybrids in Valle de San Juan (Colombia) using Inmunostrip®, PCR and ELISA tests on leaves (seed gene f low) and seeds (pollen gene f low). more than 88% of the plots were positive with the Inmunostrip® and PCR tests (35s promoter, Nos terminator and cry1F gene), using the leaves, while the remaining seven plots (12%) were positive for transgenic sequences in the seeds. The results indicated a significant level of overall transgene existence, which is consistent with gene f low from transgenic events. All of the field types (conventional maize, buffer zones, refuge, and Colombian landraces) showed evidence of a transgene presence. There are many problems that could increase the gene f low potential in Valle de San Juan, such as little respect for regulations (Colombian Decree 4525 on transgenic crops and biosafety), distance between transgenic and non-transgenic maize or use of refuge and/or buffer zones, high seed reuse and exchange and low technical assistance. Every policy decision must be made in light of scientific standards of judgment.

Toward a national plan to control health effects of mercury in Colombia

The problem of mercury effects on humans and the environment is global, and it has different impacts on health. It is necessary, therefore, to address this issue from a broad overview to identify populations at risk of exposure, health effects, the production processes involved and the actions aimed at reducing exposure and mitigating the impact. To design a conceptual and operational framework to develop strategies for prevention, control and mitigation of mercury effects on health and on the environment in Colombia. We conducted a two-phase study: a literature review following the Cochrane methodology and forums with national and international experts using a comprehensive planning methodology to identify priority actions and establish a national research agenda. The results of the review were structured into four components: mercury effects on health, legal framework in Colombia, emission inventory for the country and health plans and programs. We made recommendations for the design of an intervention plan considering five lines of action: technologies for exposure management, institutional strengthening for exposure prevention and control, strategies for strengthening diagnosis and care, health education on mercury risks, and knowledge generation. We detected information gaps, technical weaknesses, and the need of administrative and other resources in this field in Colombia. We proposed priority actions to reduce the economic, social and health impact from exposure to mercury.

Reanalysis of monthly precipitation fields in Colombian territory

The historical monthly precipitation fields in Colombia are estimated and studied for the period 1975 - 2006 at a spatial resolution of 5 minutes of arc, calculated using an optimal integration of information available at rain gauges and distributed monthly series of fields from satellite measurements and studies of reanalysis at different periods and various spatial resolutions. Space interpolation of point observations uses a variant of the PRISM model [1]. Based on a MDT, the relationship between precipitation and topography was studied, allowing the development and implementation of a model of interpolation similar to PRISM to estimate monthly precipitation fields. Considering the topographic effect as the most important factor in explaining the spatial variability of rainfall, the study area is discretized in homogeneous regions that allowed to represent adequately the presence of the pluviometric optimal height and the temporal variability imposed by the ITCZ.

Enfermera especialista en ultrasonido cardíaco. Propuesta de formación en Colombia

The practice of cardiac sonography in our country shows a very similar behavior to the rest of the world, in which accelerated technological development is coupled with a scarcity of certified professionals in the diagnostic imaging field. These professionals must be included in our teams. We need health personnel with appropriate training for the proper implementation of this diagnostic methodology. We performed a comprehensive review of the subject worldwide and made an ideal academic proposal for this field in Colombia, describing among other things, their role, qualities and competencies, professional and occupational profile.

Influencia de la capacidad de absorción sobre la innovación: un análisis empírico en las mipymes colombianas

This article presents the absorptive capacity as a multidimensional construct, and aims to determine the presence of this capacity in Colombian SMEs and its relationship with innovation, being one of the first studies in this field in Colombia. A two-stage cluster analysis was performed using a sample of 403 Colombian SMEs, in order to demonstrate that the absorption capacity is not a determinant factor of innovation in these companies, but that absorption capacity develops mainly in small businesses in Colombia. It also shows that innovation processes are determined by the competitive strategies undertaken by each type of company.

'Candidatus Phytoplasma asteris' Strains Associated with Oil Palm Lethal Wilt in Colombia.

The distribution of lethal wilt, a severe disease of oil palm, is spreading throughout South America. An incidence of about 30% was recorded in four commercial fields in Colombia. In this study, phytoplasmas were detected in symptomatic oil palm by using specific primers, based on 16S ribosomal DNA (rDNA) sequences, in nested polymerase chain reaction assays. The phytoplasmas were then identified as 'Candidatus Phytoplasma asteris', ribosomal subgroup 16SrI-B, through the use of restriction fragment length polymorphism (RFLP) analysis and sequencing. Cloning and sequencing of 16S rDNA from selected strains, together with phylogenetic analysis, confirmed the classification. Moreover, collective RFLP characterization of the groEL, amp, and rp genes, together with sequence data, distinguished the aster yellows strain detected in Colombian oil-palm samples from other aster yellows phytoplasmas used as reference strains; in particular, from an aster yellows strain infecting corn in the same country.

Application of a Nanofluid for Asphaltene Inhibition in Colombia

This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper OTC 24310, ’Application and Evaluation of a Nanofluid Containing Nanoparticles for Asphaltene Inhibition in Well CPSXL4,’ by R. Zabala, E. Mora, C. Cespedes, L. Guarin, H. Acuna, and O. Botero, Ecopetrol; J.E. Patino, Petroraza; and F.B. Cortes, Universidad Nacional de Colombia, prepared for the 2013 Offshore Technology Conference Brasil, Rio de Janeiro, 29-31 October. The paper has not been peer reviewed. Copyright 2013 Offshore Technology Conference. Reproduced by permission. This paper describes the evaluation of a nanofluid containing nanomaterials with high adsorption capacity used for asphaltene inhibition in the volatile Cupiagua Sur oil field in Colombia. Asphaltene precipitation has been identified as one of the most potentially damaging mechanisms affecting this field’s productivity. The goal of the injection of nanofluids containing nanoparticles of alumina with high surface area is to absorb the asphaltenes and carry them with the condensate, avoiding precipitation near the wellbore. Introduction The Cupiagua Sur field is located 110 km northeast of Bogota in the foothills of the Colombian Andes, close to other fields such as Floreña, Pauto, Volcanera, Recetor, Cupiagua, and Cusiana (Fig. 1). Despite the fact that Cupiagua Sur is very close to Cupiagua, this reservoir is totally independent and separate. It is a compositional volatile-oil reservoir with an average gravity of 38°API; there is no free-gas cap at initial conditions (for a discussion of asphaltene precipitation in volatile oil, please see the complete paper). The main formations are Mirador and Barco, which are quite similar in terms of petrophysical and fluid properties (average permeability is 21 md, and average porosity is 6.5%). Cupiagua Sur is a prolific oil field that in 15 years of production has recovered 88 million STB/D gross out of 189 million STB/D originally in place from Mirador and Barco reservoirs in a developed area with four producer and two injector wells. The current reservoir conditions in this field are highly dependent on the way the reservoir has been produced. The first production well, CPXP1, started producing in March 1998, while the first gas-injector well went into action in January 2000; at that time one volatile well was on production. There are currently six active wells in the field. There are four producers and two gas injectors. Oil production reached its peak in March 2001 at 41,722 STB/D. The average gas production at that date was 175 MMscf/D. Today, the recovery factors are 48.2% and 29.5% in the Mirador and Barco formations, respectively. There was no production plateau in Cupiagua Sur; instead, a constant decline rate is observed. This indicates the extreme conditions under which the reservoir was depleted, as well as the sources of damage.

Chemosystematic identification of fifteen new cocaine-bearing Erythroxylum cultigens grown in Colombia for illicit cocaine production

Colombian coca farmers have historically cultivated three varieties of coca for cocaine production (Erythroxylum novogranatense var. novogranatense, Erythroxylum novogranatense var. truxillense, and Erythroxylum coca var. ipadu). Within the past 13 years, 15 new cultigens of cocaine-bearing Erythroxylum have been propagated by Colombian coca farmers; each with differing physical characteristics, yet producing cocaine alkaloids at similar levels found in the historical and native varieties. Fifteen new cultigens were collected from throughout Colombia and propagated along with the three historical varieties within an experimental field in Colombia. Five plants/cultigen were randomly selected and examined for alkaloid content to determine their varietal characteristics when compared to the three known varieties. Ten cultigens gave classic Erythroxylum coca var. ipadu alkaloid profiles, four cultigens produced alkaloid profiles consistent with a hybridization of Erythroxylum novogranatense and Erythroxylum coca var. ipadu, while one cultigen gave heterogeneous alkaloid profiles that could not be characterized.

Towards the Configuration of an Industrial Engineering Education Field in Colombia from the Critical Didactics Pedagogy

This work I try to deliver in this paper due to the search by the sense of being a teacher-engineer, for some time. The constant search for the meaning of engineering education in environments like ours, still so dependent senses and knowledge of others, that being so alien, and imposes were simply assumed without further discussion. Industrial engineering does not arise in Colombia as a field of being able specific, with a corpus discipline clearly definitely and differentiated, which is constituted one of the motives that impedes his tracking inside engineering education history. In the statements till now opposing, there is glimpsed how this function was replaced by other engi- neers in the industry, such as chemical or mechanical engineers, maybe the only one fact that re- veals his emergence is his institutionalization as study plan in the Universidad Industrial de San- tander in 1958 The exhibition of these facts, it uses as support: The first one is that the processes of modernization and the form like formed, from the new forms of economic rationality created with the development model; they made necessary the appearance of the industrial engineering as discipline in the powers of engineering. The second one is that it is possible to form alternate speeches for the field of the industrial engineering in Colombia. This reflection becomes relevant in recent times when promoting critical thinking in engineering education has become important, from the understanding that engineering moves into the intersection between social and technical expertise should adapt to the economic, political and cultural contexts in which it is applied. To which I make use of Foucault’s notions of power and subjectivity, the Bourdieu’s notions of symbolic violence and Habermas communicative action. Finally I try to illustrate the reflection with the application of the concept “affectively critical learning” developed from the courses that I directed in the Universidad Autonoma de Colombia.

Management Strategies Optimize Drilling and Completion Operations

This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper SPE 165325, ’A Successful Optimization Case of Drilling and Completion Operations Through Management Tools and Strategies,’ by Oscar R. Silva, Guden O. Silva, and Luis I. Valderrama, Ecopetrol, prepared for the 2013 SPE Western Regional and AAPG Pacific Section Meeting and Joint Technical Conference, Monterey, California, USA, 19-25 April. The paper has not been peer reviewed. By 2010, all applicable drilling solutions had seemingly been applied to the Castilla field in Colombia. But new problems were identified, and a model of management strategies was implemented to reduce drilling and completion timing. During the resulting optimization process, the Castilla field became the model for the rest of the fields in the company portfolio. It is believed that this model might also be applied successfully to other fields. Introduction In a May 2010 evaluation, several facets of Castilla field operations were assessed: current processes, operations, and technologies; the state of drilling operations by use of management indicators; nonproductive time (NPT); field characteristics; and roles and responsibilities of personnel. The objectives were to prioritize processes by importance, create a process guide, develop a new manpower plan, improve communication, and apply technology efficiently. Optimization Evaluation Results Field Characteristics. The Castilla field is 200 km from BogotÁ in the Llanos basin. This field has three formations of heavy oil (T2, K1, and K2) to 7,500, 8,000, and 8,500 ft in true vertical depth (TVD), respectively. Most of the wells are drilled to approximately 9,500 ft in measured depth. The majority of the wells are J-shaped, with inclinations from 30 to 70°. The most common operational problems in the field were to be found at approximately 1,000-ft TVD, at the shale formation found immediately above pay zones. Optimization Model. The optimization process had three principal stages: implementation, consolidation, and optimization excellence. The development of each well had involved five steps during the drilling process: planning, implementation, control, feedback, and optimization. The drilling engineer had to plan the well; implement, explain, and communicate the plan; control the drilling while continuously monitoring parameters, ensuring compliance with the plan and the application of the lessons learned; catalog the lessons learned; and apply these lessons to new optimization plans. The working optimization model was designed around several major strategies, all developed on the basis of technical limits related to health, safety, and environment (HSE): continuous monitoring of indicators; establishment of only one line of communication; application of short-, medium-, and long-term well vision; and organization based on engineering.

Foam-EOR Pilot: Mature Volatile-Oil Reservoir Under Miscible-Gas Injection

This article, written by Senior Technology Editor Dennis Denney, contains highlights of paper IPTC 16984, ’Successful Foam-EOR Pilot in a Mature Volatile-Oil Reservoir Under Miscible-Gas Injection,’ by A. Ocampo, A. Restrepo, SPE, H. Cifuentes, SPE, J. Hester, N. Orozco, C. Gil, and E. Castro, Equion Energia, and S. Lopera and C. Gonzalez, Universidad Nacional de Colombia, prepared for the 2013 International Petroleum Technology Conference, Beijing, 26-28 March. The paper has not been peer reviewed. A successful field trial in which foam was used as a gas- injection conformance enhancer was implemented in the Cusiana field in Colombia. An extensive front-end loading (FEL), including chemical-product screening, studying foam stability at reservoir conditions, coreflood experiments, reservoir modeling, and careful selection of well candidates, was executed for this pilot. The treatment was performed in a gas-injection well in the northern part of the field that had already attained a high recovery factor (RF) with high levels of gas recycling. The operation was performed by use of a surfactant-alternating-gas (SAG) method. Introduction The Cusiana field is in the foothills of the Eastern Mountain chain in Colombia, and initial production was in 1994. The field comprises three stacked reservoirs (Mirador, Barco, and Guadalupe) and two fluid systems (both volatile oils) with a rich-gas cap at near-critical conditions (pressures and temperatures greater than 5,000 psia and 250°F, respectively). The initial in-place volumes were 1.5 billion STB of oil and more than 3 Tcf of gas, with the Mirador formation containing approximately 60% of the total fluid. Development strategies have included natural depletion, gas recycling, water injection, and gas-injection redistribution. Gas recycling and redistribution provided the best recoveries. The Mirador reservoir is a low- porosity quartzarenite with significant heterogeneities in permeability, both vertically and areally. The reservoir was developed with extensive gas reinjection, beginning in the early days of production with the gas-injection wells updip on the structure. This strategy proved beneficial from the very early stages of gas injection with regard to efficient first-contact miscibility and the favorable location of the injectors. The result has been RFs greater than 50% for most of the Mirador units. After approximately 10 years of gas reinjection, high levels of recycling were observed as a result of reservoir heterogeneities and a less-efficient gas-enrichment process because of the decrease in reservoir pressure below the minimum miscibility pressure. Those conditions led to unrecovered oil in areas that are difficult to access, such as the oil rim between the producers and the aquifer, poor-quality rock layers, and bypassed areas between the producers and injectors.

Sequestration of defensive toxins by tetrapod vertebrates: contributions in memory of John W. Daly

By the early 1990s John W. Daly, of the National Institutes of Health, had been collecting and cataloguing toxins from the skins of frogs for about 30 years, on the assumption that the enormous variety of alkaloid toxins (by then numbering in the hundreds) were synthesized by the frogs themselves (Daly 1998). However, he had begun to detect patterns that suggested the toxins might have a dietary origin, including temporal variation in toxin profiles within a population, similarity of toxins among frogs of four distantly related families (and even in a bird), the absence of alkaloids in captive-bred frogs, and the discovery of some identical compounds in a variety of small arthropods (Saporito et al. 2009). In a series of experiments in the mid1990s, Daly and his collaborators demonstrated that captive-reared and nontoxic frogs of the genus Dendrobates could acquire toxins from prey that had been dusted with alkaloids in the lab (Daly et al. 1994b). Furthermore, captive-reared frogs would, if housed with access to wild arthropods as prey, acquire alkaloid toxins (Daly et al. John W. Daly in the field in Colombia, 1970 (left from Myers 2009, courtesy of Charles W. Myers and Robert W. Hansen) and Panama, 2003 (right courtesy of Maureen A. Donnelly)

Real-time PCR detection of Plasmodium directly from whole blood and filter paper samples

BackgroundReal-time PCR is a sensitive and specific method for the analysis of Plasmodium DNA. However, prior purification of genomic DNA from blood is necessary since PCR inhibitors and quenching of fluorophores from blood prevent efficient amplification and detection of PCR products.MethodsReagents designed to specifically overcome PCR inhibition and quenching of fluorescence were evaluated for real-time PCR amplification of Plasmodium DNA directly from blood. Whole blood from clinical samples and dried blood spots collected in the field in Colombia were tested.ResultsAmplification and fluorescence detection by real-time PCR were optimal with 40× SYBR® Green dye and 5% blood volume in the PCR reaction. Plasmodium DNA was detected directly from both whole blood and dried blood spots from clinical samples. The sensitivity and specificity ranged from 93-100% compared with PCR performed on purified Plasmodium DNA.ConclusionsThe methodology described facilitates high-throughput testing of blood samples collected in the field by fluorescence-based real-time PCR. This method can be applied to a broad range of clinical studies with the advantages of immediate sample testing, lower experimental costs and time-savings.

Application of Horizontal Wells To Reduce Condensate Blockage in Gas/Condensate Reservoirs

This article, written by Senior Technology Editor Dennis Denney, contains highlights of paper SPE 130996, ’Application of Horizontal Wells To Reduce Condensate Blockage in Gas/ Condensate Reservoirs,’ by Nathan Miller, SPE, Hadi Nasrabadi, SPE, Texas A&M University-Qatar, and Ding Zhu, SPE, Texas A&M University, prepared for the 2010 SPE International Oil & Gas Conference and Exhibition in China, Beijing, 8-10 June. The paper has not been peer reviewed. Much of the world’s gas reserves can be found in gas/condensate reservoirs. These reservoirs, from a recovery and deliverability standpoint, can have significant differences from oil reservoirs. When the pressure, either in the wellbore or in the reservoir, drops below the dewpoint pressure, a condensate phase appears that reduces gas production significantly. In this study, horizontal wells were used in a giant gas/condensate reservoir (North field, Qatar) to reduce the condensate blockage. Critical questions are: What fraction of a horizontal well’s increased gas production results from the increased formation contact and what fraction results from reducing condensate blockage? Introduction The largest gas/condensate reservoirs include the Arun field in Indonesia; the Cupiagua field in Colombia; the Karachaganak field in Kazakhstan; the North field in Qatar, which borders with the South Pars field in Iran; and the Shtokmanovskoye field in the Russian Barents Sea. All of these fields have one thing in common—condensate blockage. Condensate blockage occurs when a liquid phase forms around the wellbore because the pressure falls below the dewpoint pressure. Production performance can decrease significantly if these condensate-banking effects are not understood at the beginning of field development. Retrograde gases exhibit a lower gas/oil ratio (GOR) limit of 3,300 scf/STB and an upper GOR limit of 150,000 scf/STB. Retrograde gases have stock-tank liquid gravities between 40 and 60°API and can be lightly colored orange, brown, or greenish or can be clear. The North field is a massive offshore gas/condensate reservoir with more than 900 Tcf of proven natural-gas reserves. The abnormally pressured field covers more than 6000 km2. As Fig. 1 shows, the North field adjoins Iran’s South Pars field, which has 280 Tcf of recoverable natural-gas reserves. The initial reservoir pressure was 5,300 psi, and the initial reservoir temperature was 220°F. The field produces from a carbonate reservoir called the Khuff formation (late Permian to early Triassic). The Khuff formation consists of four noncommunicating, highly stratified layers. Discovered in 1971, North field appraisal drilling occurred over the next 14 years to quantify the reservoir-gas accumulations and to determine the reservoir-fluid and geological characteristics. The Alpha Project began in 1991 to develop the field’s reserves by producing natural gas and condensate from the Lower Khuff. The first concession was awarded in 1993, the first delivery of condensate occurred in 1996, and the first delivery of liquefied natural gas took place in 1997.

Casabe Mature-Field Revitalization Through an Alliance: A Case Study of Multicompany and Multidiscipline Integration

This article, written by Senior Technology Editor Dennis Denney, contains highlights of paper SPE 122874, ’Casabe Mature-Field Revitalization Through an Alliance: A Case Study of Multicompany and Multidiscipline Integration,’ by L. Marquez, SPE, J. Elphick, SPE, and J. Peralta, Schlumberger, and M. Amaya and E. Lozano, Ecopetrol S.A., prepared for the 2009 SPE Latin American and Caribbean Petroleum Engineering Conference, Cartagena, Colombia, 31 May-3 June. The paper has not been peer reviewed. The achievements of an alliance between Ecopetrol S.A. and Schlumberger to revitalize the Casabe field, a mature field in Colombia, are highlighted. Challenges were multifaceted in this mature complex field. Some related to the heterogeneous nature of the reservoirs, limited sand continuity, unfavorable mobility for the ongoing waterfloods, associated sand production, and wells lost because of collapses. Introduction The Casabe field, discovered by Shell in 1941, is in the Mid-Magdalena Valley basin in Colombia and contains 1,120 wells. Cumulative production was 284 million bbl of oil as of December 2007. The productive-formation depths range from 2,200 to 5,500 ft. The production peaked at 46,000 BOPD in 1953 and achieved a primary recovery factor of 13% under natural mechanisms. Since 1985, the field has been under waterflood, which increased recovery to 19.8%. Waterflooding has been a challenge because of the very heterogeneous nature of the reservoirs, sand-continuity complexity, oil viscosity, sand production, and wells lost to collapses. Since 2004, the alliance has worked to revitalize this mature field to increase its value by use of field management. A joint team was assembled to determine key factors related to the past behavior. This method provided the best way to improve future management practices and increase production. Key factors to be managed in the Casabe field are the waterflooding behavior, casing-collapse mechanisms, and sand-production problems. The team developed analytical and numerical models to understand these issues. Some of the models were complemented with laboratory analyses along with well tests. All areas are integrated within the reservoir-management philosophy, which means they are all interrelated. Casabe Field: History vs. Future Initially, the Casabe field was under-saturated and produced under primary mechanisms (mainly natural depletion) until the mid-1980s when a waterflood was initiated. Most of the gas had already been produced, and oil rates were down to 10 BOPD/well. The waterflood tripled the per-well oil production, but many inefficiencies remained, which made it difficult to obtain better performance.