80 research outputs found

    Assessing Susceptibility to Soil Liquefaction Using the Standard Penetration Test (SPT)—A Case Study from the City of Portoviejo, Coastal Ecuador

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    The city of Portoviejo in coastal Ecuador was severely affected during the 16 April 2016, Pedernales earthquake (Mw 7.8). Various coseismic liquefaction phenomena occurred, inducing lateral spreading, sand boils, ground subsidence, and sinkholes in soils with poor geotechnical quality in the alluvial and alluvial–colluvial sedimentary environment. Therefore, the main aim of this study was to collect data from standard penetration tests (SPT) and shear velocity and exploratory trenches and to calculate the liquefaction potential index (LPI) by considering a corresponding seismic hazard scenario with an amax = 0.5 g. From these data, a liquefaction hazard map was constructed for the city of Portoviejo, wherein an Fs of 1.169 was obtained. It was determined that strata at a depth of between 8 and 12 m are potentially liquefiable. Our quantitative results demonstrate that the city of Portoviejo’s urban area has a high probability of liquefaction, whereas the area to the southeast of the city is less sensitive to liquefaction phenomena, due to the presence of older sediments. Our results are in accordance with the environmental effects reported in the aftermath of the 2016 earthquake.This research was jointly supported by the Technical University of Manabí in Ecuador. With the particular support of the Soil and Concrete Mechanics laboratory “Suelcon & Asf”

    Origem das variações de cores das escórias do vulcão Sierra Negra das Ilhas Galápagos

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    Volcanic cinder, also known as scoria, is an extrusive igneous rock that forms when gas-rich magmas of basaltic or andesitic composition cool quickly. It is typically dark in color, ranging from black to red depending on its chemical composition. Sometimes fresh cinder samples show a variety of shiny metallic colors on its surface ranging from blue to gold to silver. The origin of these colors has remained unknown up to now. Cinder samples from an eruptive event occurred in October 2005 have been collected in the surroundings of the Sierra Negra volcano in the Galápagos Islands. The samples’ crystallographic structure, chemical composition, and surface morphology have been analyzed using X-Ray diffractometry (XRD), energy dispersive X-Ray spectroscopy (EDS) and a field gun emission scanning electron microscopy (SEM), respectively. Based on an extensive physical and chemical analysis, we were able to demonstrate that these colors are due to a light interference phenomenon. These results have a great potential to be used for a wide variety of purposes such as determining the temperature and composition of magma and evaluating volcanic samples for planetary studies.Las cenizas volcánicas, también conocidas como escorias, son una roca ígnea extrusiva que se forma cuando los magmas ricos en gas de composición basáltica o andesítica se enfrían rápidamente. Es típicamente de color oscuro, que va del negro al rojo dependiendo de su composición química. A veces las muestras de ceniza fresca muestran una variedad de colores metálicos brillantes en su superficie que van del azul al oro y a la plata, dependiendo de la orientación de la muestra. Hasta ahora, el origen de estos colores ha permanecido desconocido. Muestras de cenizas de un evento eruptivo ocurrido en octubre de 2005, han sido recogidas en los alrededores del volcán Sierra Negra en las Islas Galápagos. La estructura cristalográfica, la composición química y la morfología de la superficie de estas muestras se han analizado utilizando la difracción de rayos X (XRD), la espectroscopia de rayos X de dispersión de energía (EDS) y la microscopia electrónica de barrido con emisión de campo (SEM), respectivamente. Basándonos en un extenso análisis físico y químico, hemos podido demostrar que estos colores se deben a un fenómeno de interferencia de la luz. Estos resultados tienen un gran potencial para ser utilizados para una amplia variedad de propósitos como la determinación de la temperatura y la composición del magma, así como la evaluación de muestras volcánicas para estudios planetarios.As cinzas vulcânicas, também conhecidas como escórias, são uma rocha ígnea extrusiva formada quando os magmas ricos em gás de composição basáltica ou andesítico esfriam rapidamente. É tipicamente de cor escura, que vai do preto ao vermelho, dependendo de sua composição química. Às vezes as amostras de cinza fresca mostram uma variedade de cores metálicas brilhantes em sua superfície que vão do azul ao ouro e à cor prata, dependendo da orientação da amostra. Até o momento, a origem destas cores permanece desconhecida. Amostras de cinzas de um evento eruptivo ocorrido em outubro de 2005, foram recolhidas nos arredores do vulcão Sierra Negra nas Ilhas Galápagos. A estrutura cristalográfica, a composição química e a morfologia da superfície destas amostras foram analisadas por meio da difração de raios X (XRD), da espectroscopia de raios X por energia dispersiva (EDS) e da microscopia eletrônica de varredura com emissão de campo (SEM), respectivamente. Com base em uma extensa análise física e química, pudemos demonstrar que essas cores se devem a um fenômeno de interferência da luz. Esses resultados têm um grande potencial para serem utilizados com uma ampla variedade de propósitos como a determinação da temperatura e a composição do magma, bem como a avaliação de amostras vulcânicas para estudos planetários

    Nova spoznanja o nastanku piroduktov Galapaškega otočja, Ekvador

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    There has been little research on the genesis and development of pyroducts (or lava tubes) originating from Gala´pagos volcanoes. Pyroducts are responsible for the lateral, post-eruptive transport of lava because they are highly effective as thermal insulators. After eruptions terminate, these conduits often become accessible as caves. In March 2014 the 16th International Symposium on Vulcanospeleology brought a large group of vulcanospeleological specialists to the Islands. During the meeting a number of pyroducts were visited and studied in context on the island of Santa Cruz and around Isabella’s Sierra Negra volcano in the western, most active, part of the Gala´pagos. The longest of the caves, Cueva del Cascajo, about 3 km in length, was partly surveyed and nine other caves were visited. Structural features such as thickness of roof, evidence of downcutting, presence of oxbows, secondary ceilings, lavafalls, collapses and pukas were particularly studied for evidence they reveal about developmental stages of pyroducts. The resulting data show that the pyroducts were formed by "inflation" with the primary roof consisting of uninterrupted paŻhoehoe sheets. No pyroducts were identified that developed by the crusting-over of channels. The studies strongly confirm inferences drawn from other hot-spot related islands, such as Hawai’i.Raziskav o nastanku in razvoju piroduktov ali lavinih cevi na galapaških vulkanih je malo. Pirodukti so pomembni za bočni transport lave po izbruhu in so toplotni ščit med tokom lave in zunanjim ozračjem. Po končanem izbruhu ti kanali ostanejo dostopni kot lavine cevi. Marca 2014 je na Galapaškem otočju potekal 16. mednarodni simpozij o vulkanospeleologiji. V okviru tega smo obiskali in proučevali številne pirodukte na otoku Santa Cruz in v okolici vulkana Isabella's Sierra Negra na zahodnem, najaktivnejšem delu Galapaškega otočja. Delno smo izmerili najdaljšo, 3 km dolgo jamo Cueva del Cascajo in obiskali še devet drugih jam. Pri tem smo bili pozorni na strukturne elemente, ki kažejo na razvojne faze piroduktov, kot so debelina stropa, vrezovanje, prisotnost obvodnih rovov (oxbow), ostankov lavinih slapov, sekundarnih stropov, odprtin na površje (puka) in vdorov. Podatki in opažanja kažejo, da so jame nastale z zaporednim napredovanjem in napihovanjem, na kar kaže tudi primarni strop iz neprekinjenih plasti pahoehoe lave.. Nobeden od piroduktov ni nastal zaradi strjevanja lave nad tokom. Podobne ugotovitve veljajo tudi jame na vulkanih drugih vročih točk, kot na primer na havajskih vulkanih

    ¿Influye la proximidad física en el conocimiento de la estructura y formación de los volcanes? Un estudio de caso empírico en dos escuelas alemanas en Ecuador

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    Ecuador ist weltweit das Land mit der größten Dichte an Hochrisikovulkanen. Wirkt sich dies auf das Wissen von Schülerinnen und Schülern über Vulkanismus aus? Der vorliegende Beitrag liefert Teilergebnisse einer umfassenden Gesamtstudie über das Wissen von Schülerinnen und Schülern aus Ecuador über den Aufbau und die Entstehung von Vulkanen/Vulkanismus. Es wurden Schülerinnen und Schüler der Jahrgangsstufe 6 an den Deutschen Schulen in Quito und Guayaquil befragt, die in der Schule noch keinen Unterricht über Vulkanismus hatten. Zusätzlich wurden auch Daten von Schülerinnen und Schülern der Jahrgangsstufe 12 durch Befragungen erhoben. Die Ergebnisse dieser Teilstudie deuten auf einen Einfluss des Schulstandortes (Nähe zu Hochrisikovulkanen) auf das Wissen über die Entstehung und den Aufbau von Vulkanen/Vulkanismus hin.Ecuador is characterized by the highest density of high-risk volcanoes worldwide. Does this affect students’ knowledge of volcanism? This paper provides partial results of a comprehensive overall study of the knowledge of students from Ecuador about the structure and development of volcanoes/volcanism. The study used a questionnaire administered to sixth-grade students without prior formal training on volcanoes and volcanism. Twelfth-grade students also This questionnaire was also answered by high school students. In addition, the questionnaire was also presented to twelfth-graders. The results of this sub-study indicate an influence of the proximity to high-risk volcanoes on the knowledge about the formation and structure of volcanoes/volcanism.Ecuador se caracteriza por contar con la mayor densidad de volcanes de alto riesgo en todo el mundo. ¿Afecta esto a los conocimientos que tienen los estudiantes sobre el vulcanismo? Este trabajo proporciona resultados parciales de un estudio global y completo acerca del conocimiento que tienen los estudiantes de Ecuador sobre la estructura y el desarrollo de los volcanes. Para desarrollar el estudio se utilizó un cuestionario que fue facilitado a los estudiantes de sexto grado sin entrenamiento formal previo sobre volcanes y vulcanismo. Igualmente, también fue proporcionado a los estudiantes de 12º grado y a los de secundaria. Los resultados de este estudio indican que existe influencia en el conocimiento de los volcanes en función de la proximidad en aspectos relacionados con la formación y estructura de los volcanes

    A container orchestration development that optimizes the etherpad collaborative editing tool through a novel management system

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    The use of collaborative tools has notably increased recently. It is common to see distinct users that need to work simultaneously on shared documents. In most cases, large companies provide tools whose implementations have been a very complicated and expensive task. Likewise, their platform deployment requirements should be robust hardware infrastructures. It becomes even more critical when their main target is to reach scalability and highavailability. Therefore, this study aims to design and implement a microservices-based collaborative architecture using assembled containers in the cloud, enabling them to deploy Etherpad instances to guarantee high availability. To ensure such a task, we developed and optimized a central management system that creates Etherpad instances and continuously interacts with other Etherpad tools running on Docker containers. This design goes from the monolithic Etherpad instantiation and handling towards a service architecture, where every Etherpad is offered as a microservice. Furthermore, the management system follows (implements) the Observer, Factory Method, Proxy, and Service Layerpopular design patterns. This allows users to gain more privacy through access to validations and shared resources. Our results indicate both the correct operation in the automation of containers’ creation for new users who register in the system and quantifiable improvement in performance.The funding of this research is provided by the Mobility Regulation of the Universidad de las Fuerzas Armadas ESPE, from Sangolquí, Ecuado

    Soil Liquefaction and Other Seismic-Associated Phenomena in the City of Chone during the 2016 Earthquake of Coastal Ecuador

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    The city of Chone, being situated on the Ecuadorian coast, was affected due to the close-by epicenter of the earthquake of 16 April 2016, which reached a magnitude of Mw 7.8. This catastrophic event presented settlements in the ground, sand boils and land subsidence, being the most damaging in a variety of civil works among these several buildings. The main objective of the current study is to select data using the standard penetration test (SPT) for the evaluation of the probability of liquefaction considering a maximum acceleration seismic risk of amax = 0.5 g. With the tabulated information, a liquefaction hazard map was generated for the city of Chone, where a safety factor of 1228 was obtained, determining the potentially liquefiable strata at an approximate depth between 9 and 11 m. Hereby, we were able to demonstrate results that were obtained experimentally through a quantitative analysis, indicating that the urban area of the city of Chone has a high probability of liquefaction, which was supported due to the presence of Holocene-aged soils developed in alluvial deposits, located in an alluvium mid catchment area. This novel research, due to the combination of a variety of used tools in the seismic risk evaluation, provides a relevant contribution to territorial planning and risk management in construction, in addition to the territorial reorganization of the canton as an example for different regions worldwide with similar geodynamics, soil mechanics and seismic vulnerabilities.This research was performed with the support of the private Soil Mechanics Laboratory “Suelcon & Asf” of the province of Manabi

    ANALYSIS OF LOCAL RISK PERCEPTION IN THE EVENT OF A TSUNAMI – A CASE STUDY IN MANTA, COASTAL ECUADOR

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    Local perception of risk is a determinant of urban vulnerability. Accordingly, this research addresses the analysis of local perception of the risk of tsunami hazards occurrences and this case study focuses on an area of the Tarqui parish in the city of Manta in coastal Ecuador. This work also presents the possible tsunamigenic seismic source in the subduction zone of the study area. The Tarqui Zone is located within a coastal and fluvial landscape that currently the enlargement of the urban limit has obstructed the free flow of these systems. Based on the tsunami hazard map for the city of Manta, we determined that there are 392 sites in an area with high susceptibility to flooding. There are also 996 sites with medium susceptibility to floods in a zone of maximum influence between the levels of 7 to 20 m.a.s.l, sites in which the flood processes and corresponding erosion may not be very intense. In addition, the perception of this hazard was strengthened using context indicators on local tsunami risk perception based on a survey format for heads of households. In this regard, the given surveys indicate that 29 per cent of the population is in a state of high vulnerability, 63 per cent are in a situation of medium vulnerability and only 8 per cent are in a position of low vulnerability. With the obtained results we realized curves of frequency of perception of the population regarding this hazard, which will serve for the authorities to improve their response plans

    Análisis de datos de exceso de mortalidad por infecciones y muertes por COVID-19 en Ecuador

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    The global COVID-19 pandemic has shocked the world. Since the virus gave rise to health problems and often ended in deaths, the count of the contagion and the deceased has been an open issue. Such statistics are vital for every nation and even every city or district and suburb as these numbers decide the level of intervention and the subsequent reduction of its given spread. Worldwide data show a mortality rate of around two percent prior to successful vaccination campaigns. However, Ecuador's statistical data indicate an abnormal amount of excess mortality, which is officially denied in each of the studied countries. These numbers have been projected on a monthly basis and exceed up to 300% of the official COVID-19 deaths. In particular, the average mortality rate in Ecuador, prior to and close to the pandemic, has been about 6083.4±234.6, while in the worst month during the sanitary crisis, deaths piled up to 21,000 people, and only 1180 were recognized as deceased by COVID-19. The reasons are widespread but based on an insufficient financed health sector, political incompetence, lack of leadership, and a long-lasting economic crisis. Therefore, premature endings of confinements or lockdowns have contributed to an accelerated contagion and seem to even counteract the vaccination phase, in middle 2021, shortly before excess mortality ceased completely.La pandemia mundial de COVID-19 ha conmocionado al mundo. Dado que el virus dio lugar a problemas de salud y, a menudo, terminó en muertes, el recuento del contagio y de fallecimientos ha sido un tema abierto. Estas estadísticas son vitales para cada nación e incluso para cada ciudad o distrito y suburbio, ya que estos números deciden el nivel de intervención y la consiguiente reducción de su extensión dada. Los datos mundiales indican una tasa de mortalidad de alrededor del dos por ciento antes de campañas de vacunación exitosas. Sin embargo, los datos estadísticos de Ecuador indican una cantidad anormal de exceso de mortalidad, que oficialmente se niega en cada uno de los países estudiados. Estas cifras se han proyectado mensualmente y superan hasta el 300 % de las muertes oficiales por COVID-19. En particular, en Ecuador la tasa de mortalidad promedio antes y cerca de la pandemia ha sido de alrededor de 6 083,4 ± 234,6, mientras que en el peor mes de la crisis sanitaria, las muertes ascendieron a 21 mil personas, pero solo se reconocieron 1 180 como personas fallecidas por COVID-19 o con este. Las razones son generalizadas, pero se basan en un sector de salud insuficientemente financiado, incompetencia política, falta de liderazgo y una crisis económica de larga duración. Por lo tanto, las terminaciones prematuras de los confinamientos o encierros han contribuido a un contagio acelerado y parecen incluso contrarrestar la fase de vacunación, a mediados de 2021, poco antes de que el exceso de mortalidad cesara por completo

    EFECTOS CONTRASTIVOS DE LA EVALUACIÓN DE LA CONTAMINACIÓN AMBIENTAL EN DOS ZONAS DEL DISTRITO METROPOLITANO DE QUITO, ECUADOR

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    Uno de los principales factores de contaminación del aire dentro de las zonas urbanas es la quema de gasolina por parte de autos, camiones ligeros y motocicletas. La quema de gasolina libera gases contaminantes como el dióxido de nitrógeno, el dióxido de azufre, el monóxido de carbono y el benceno, entre otros. Entre ellos, el dióxido de nitrógeno (NOx) es el que destaca por la concienciación de la gente sobre dicha contaminación. En esta investigación se utilizó el Método de los Precios Hedónicos (MPH) para determinar la percepción de la gente sobre la calidad del aire como indicador y estimar el efecto de los gases en el mercado inmobiliario. Se seleccionaron dos zonas del Distrito Metropolitano de Quito para evaluar los efectos de la contaminación en los inmuebles. Una con mayor concentración de gases ubicada dentro del casco histórico de Quito, y la otra con mejor calidad de aire conocida como el sector Bellavista. Los resultados de los tres modelos diferentes indicaron que una reducción de 1 (μg/m3) de NOx aumentaría un promedio de 4,54% el valor del mercado inmobiliario, lo que representa un valor de USD 2.032.326,24 para las propiedades de la muestra. Una disminución de 5 (μg/m3) aumentaría en un 22,7% el valor de las propiedades./ One of the main factors of air contamination within urban areas is burning gasoline by cars, light trucks and motorcycles. Gasoline burning liberates pollution gases such as Nitrogen dioxide, Sulfur dioxide, Carbon monoxide, benzene, besides others. Among these, Nitrogen dioxide (NOx) is the one that stands out for the people’s awareness of such contamination.We used the Hedonic Price Method (HPM) in order to determine people’s perception of air quality as a proxy and estimate the effect of gases on the housing market. We selected two areas of Quito Metropolitan District in order to evaluate contamination effects on properties. One with a higher concentration of gases located within the historic district of Quito. The other with better air quality called the Bellavista district. The results of three different models indicated that a reduction of 1 (μg/m3) of NOx would increase an average of 4.54% of the housing market value, which it represents 2,032,326.24 USD in value for sample properties. A decrease of 5 μg/m3 will increase in 22.7% of properties value

    Multitemporal analysis as a non-invasive technology indicates a rapid change in land use in the Amazon: The case of the ITT oil block

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    Producción CientíficaThe Amazon Region of Ecuador (ARE) hosts a great variety of biodiversity and ecosystems. These hotspots are internationally recognized for presenting unique fauna and flora found nowhere else in the world. Within the ARE, there is the Yasuní National Park (YNP), a recognized Biosphere Reserve located in the sub-basins of various rivers. The study area is the “ITT Oil Block” (Ishpingo, Tambococha, and Tiputini), situated in the Province of Orellana and superimposed on the YNP. The block has an area of 179,449.53 ha. The main objective of the current study was to analyze the multi-temporality of land-use change in the ITT Oil Block of the ARE. In the methodological process, the PCI Geomatic and ARCGIS programs were used for the processing and classification of satellite images (Landsat 7 and 8). The changes in land use in the ITT Oil Block over the three periods (2001, 2014, and 2017) indicated that forest cover decreased by 24.23% in soils, while infrastructure and cultivation increased throughout the time period by 0.27% and 0.23%, respectively. The most significant land-use change rate in the ITT Oil Block in the period 2001–2017 are the categories of bare soil with 9.01% (10,640.82 ha) and cultivation with 7.27% (591.29 ha)
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