Browsing by Author "Taipe, Edu"
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Item Open Access Actividad sismo-volcánica asociada a la erupción del volcán Ubinas en 2006-2008(XIV Congreso Peruano de Geología, 2008) Macedo Sánchez, Orlando Efraín; Métaxian, Jean-Philippe; Taipe, Edu; Ramos Palomino, Domingo A.El 25 de marzo 2006, pobladores del valle situado al SE del volcán Ubinas (16º 22’ S, 70º 54’ W; 5672 m) alertan sobre rugidos provenientes del volcán y de caída de cenizas sobre sus sembríos. Este volcán, considerado como el más activo del Perú en los últimos 500 años, había entrado nuevamente en erupción, amenazando a más de 3500 pobladores que habitan en el valle del río Ubinas. El Instituto Geofísico del Perú (IGP) en cooperación con el Institut de Recherche pour le Developpement (IRD-France) ha efectuado el monitoreo y la vigilancia de la actividad sísmica asociada al proceso eruptivo, primero mediante 2 estaciones sísmicas digitales de banda ancha y posteriormente mediante una red de hasta cuatro estaciones sísmicas digitales (3 de 1 Hz y una de banda ancha), las cuales transmiten los datos hasta el Observatorio Volcanológico de Cayma en Arequipa. Presentamos las principales características de la evolución de la sismicidad observada, usando los datos de a red sísmica radio-telemétrica. Anteriormente, durante tres semanas en marzo-abril 1998 (Taipe, 2008), se realizó un monitoreo sísmico mediante una red de 6 estaciones sísmicas digitales RefTek equipadas con 2 sismómetros digitales 3C de banda ancha y otros 4 sismómetros 3C de periodo corto desplegados sobre todo el edificio. Estos estudios determinaron la existencia de una importante sismicidad (Fig 1) caracterizada por diverso tipo de sismos asociados a fracturas (VT) y paso de fluidos (LP, tremores y tornillos) en las inmediaciones del cono.Item Restricted Magma extrusion during the Ubinas 2013-2014 eruptive crisis based on satellite thermal imaging (MIROVA) and ground-based monitoring(Elsevier, 2015-09) Coppola, Diego; Macedo Sánchez, Orlando Efraín; Ramos Palomino, Domingo A.; Finizola, Anthony; Delle Done, Dario; Del Carpio Calienes, José Alberto; White, Randall; McCausland, Wendy; Centeno Quico, Riky; Rivera, Marco; Apaza, Fredy; Ccallata, Beto; Chilo, Wilmer; Cigolini, Corrado; Laiolo, Marco; Lazarte, Ivonne; Machaca, Roger; Masias, Pablo; Ortega, Mayra; Puma Sacsi, Nino; Taipe, EduAfter 3 years of mild gases emissions, the Ubinas volcano entered in a new eruptive phase on September 2nd, 2013. The MIROVA system (a space-based volcanic hot-spot detection system), allowed us to detect in near real time the thermal emissions associated with the eruption and provided early evidence of magma extrusion within the deep summit crater. By combining IR data with plume height, sulfur emissions, hot spring temperatures and seismic activity, we interpret the thermal output detected over Ubinas in terms of extrusion rates associated to the eruption. We suggest that the 2013–2014 eruptive crisis can be subdivided into three main phases: (i) shallow magma intrusion inside the edifice, (ii) extrusion and growing of a lava plug at the bottom of the summit crater coupled with increasing explosive activity and finally, (iii) disruption of the lava plug and gradual decline of the explosive activity. The occurrence of the 8.2 Mw Iquique (Chile) earthquake (365 km away from Ubinas) on April 1st, 2014, may have perturbed most of the analyzed parameters, suggesting a prompt interaction with the ongoing volcanic activity. In particular, the analysis of thermal and seismic datasets shows that the earthquake may have promoted the most intense thermal and explosive phase that culminated in a major explosion on April 19th, 2014. These results reveal the efficiency of space-based thermal observations in detecting the extrusion of hot magma within deep volcanic craters and in tracking its evolution. We emphasize that, in combination with other geophysical and geochemical datasets, MIROVA is an essential tool for monitoring remote volcanoes with rather difficult accessibility, like those of the Andes that reach remarkably high altitudes.Item Restricted Morphology, structure and kinematics of a rainfall controlled slow‐moving Andean landslide, Peru(Wiley, 2016-09-15) Zerathe, Swann; Lacroix, Pascal; Jongmans, Denis; Marino, Jersy; Taipe, Edu; Wathelet, Marc; Pari, Walter; Smoll, Lionel Fidel; Norabuena Ortiz, Edmundo; Guillier, Bertrand; Tatard, LucileThe large slow‐moving landslide of Maca is located in the upper Colca valley (southern Peru), a region characterized by a well pronounced rainy period, and intense and recurrent sustained seismicity. The landslide, developed in deep lacustrine deposits, has recently accelerated, threatening the Maca village. This work aims at understanding the rupture mechanism and the causes of the recent landslide reactivation/acceleration. We present a multidisciplinary characterization of the Maca landslide that includes: (i) geological and morphological mapping in the field; (ii) remote sensing analysis using an historical aerial photograph of 1955 and the Pléiades satellite images (2013); (iii) global positioning system (GPS) including time‐series of surveys over 13 years, and continuous measurements over 14 months; (iv) a geophysical campaign with deep electrical resistivity tomography profiles acquired across the landslide mass. Our study shows that this 60 Mm3 landslide, which can be classified as a clay/silt compound landslide, moved by 15 m between 2001 and 2014 with a large inter‐annual velocity variation (up to a factor of 500) depending on the rainfall intensity. We suggest that these dramatic changes in velocity are the result of the combination of a threshold mechanism and the short intense rainy season in Peru. This study reveals three main driving factors acting at different timescales: (i) over several decades, the river course has significantly changed, causing the Maca landslide reactivation in the 1980s due to the erosion of its toe; (ii) at the year scale, a minimum amount of rainfall is required to trigger the motion and this amount controls the landslide velocity; (iii) transient changes in slide velocity may occur anytime due to earthquakes. This study particularly highlights the non‐linear behaviour of the motion with rainfall.Item Open Access Observaciones de intranquilidad en el volcán Sabancaya iniciada el 22 de febrero de 2013(Instituto Geofísico del Perú, 2013) Macedo Sánchez, Orlando Efraín; Ramos, D.; Centeno Quico, Riky; Ticona, Javier; Masias, Pablo; Machacca, Roger; Aguilar, Victor; Taipe, Edu; Antayhua, Yanet; Paxi, R.; Anccasi, Rosa; Apaza, FredyEl 22 de Febrero 2013 en un lapso de solo 95 minutos han ocurrido 3 sismos de magnitudes 4.6, 5.2 y 5.0 ML en inmediaciones del volcán Sabancaya (15.78° S, 71.85°W, 5976 m, Fig 1), en el sur del Perú, causando destrucción de 18 viviendas en Maca, poblado situado en el valle del Colca, a 20 km al NE del cráter.Item Open Access Resultados preliminares de un experimento de tomografía sísmica de la zona volcánica del sur del Perú(Sociedad Geológica del Perú, 2012) Macedo Sánchez, Orlando Efraín; Valette, Bernard; Monteiller, Vadim; Taipe, EduSe presenta resultados preliminares de un experimento de tomografía sísmica realizada desde 2006 en el segmento peruano de la ZVC de los Andes en el marco de una colaboración entre el Instituto Geofísico del Perú (IGP) y el Instituto de Investigación para el Desarrollo (IRD-Francia). No obstante que el segmento de esta parte de la subducción está caracterizada por un aumento de la pendiente de la placa subducida, la topología de esta placa y de sus contorsiones al nivel del codo de Arica permanecen mal descritas a pesar de los pocos estudios anteriores (Hasegawa & Sacks, 1981; Grange et al., 1984 ; Schneider & Sacks, 1987; Dorbath, 1997). Por otro lado las estructuras de alimentación del arco desde la placa subducida hasta los reservorios de almacenamiento magmático permanecen totalmente desconocidas. El objetivo de este estudio es aportar algunos elementos de respuesta a estas preguntas aportando entre otros un primer modelo topográfico de la esquina mantélica continental al nivel de esta zona.Item Open Access Seismic monitoring of 2006 Ubinas volcano eruption(EGU General Assembly, 2007) Macedo Sánchez, Orlando Efraín; Métaxian, J-P.; Ramos Palomino, Domingo A.; Araujo, S.; Taipe, EduAt the end of March 2006, Ubinas volcano (16.355º S, 70.903º W, 5672 m) considered the most active volcano of Peru during the last 450 years begun a new eruption process which is lasting until present. The Geophysical Institute of Peru (IGP) with the cooperation of the Institut de Recherche pour le Developpement (IRD-France) has carried out the monitoring and surveillance of seismic activity associated to this eruptive process, at the beginning by 2 digital broadband portable seismic stations and later by a network of 3 digital 1Hz stations which data is transmitted by radio telemetry to Cayma Volcanological Observatory at Arequipa city. Here we present the main characteristics about the evolution of the seismicity during this eruptive process that permitted to us to distinguish, considering also the terrain observations, that there were 4 stages during the process: (1) From March 25th to June 24th : Setting up of intrusive system, openning of the eruptive conduits. During this stage the magma arrive for the first time to the surface on April 19th. The seismic signal includes a few tremors, but they increase with the time. It take place strong explosions with LP precursor events (2) From June 24th to July 16th: Open system functioning, weak flow. Seismic signal have some tremor but the explosions are numerous --until 3 par day—and they do not show LP precursor events anymore. (3) From July 16th to august 31st: Increase of eruptive flow. Seismic signals show a remarkable increase in the last of tremors and especially in their amplitude. The energy of explosions rise and LP precursors appear again. (4) From September to January: probable end of the intrusive episode; magma volume depletion. The intrusion stopped and residual magma remains surrounding the crater area. There are some phreatomagmatic explosions because rainy season. The seismic signals show very few explosions and tremors. The number of LP decrease also, and the daily cumulated energy fall down. The precursor LP events, which precede numerous explosions, were analyzed and used for to emit explosion warnings communicated to the civil protection authorities.Item Open Access Short term forecasting of explosions at Ubinas volcano, Perú(American Geophysical Union, 2011-11) Traversa, P.; Lengliné, O.; Macedo Sánchez, Orlando Efraín; Metaxian, J. P.; Grasso, J. R.; Inza Callupe, Lamberto Adolfo; Taipe, EduMost seismic eruption forerunners are described using Volcano‐Tectonic earthquakes, seismic energy release, deformation rates or seismic noise analyses. Using the seismic data recorded at Ubinas volcano (Perú) between 2006 and 2008, we explore the time evolution of the Long Period (LP) seismicity rate prior to 143 explosions. We resolve an average acceleration of the LP rate above the background level during the 2–3 hours preceding the explosion onset. Such an average pattern, which emerges when stacking over LP time series, is robust and stable over all the 2006–2008 period, for which data is available. This accelerating pattern is also recovered when conditioning the LP rate on the occurrence of an other LP event, rather than on the explosion time. It supports a common mechanism for the generation of explosions and LP events, the magma conduit pressure increase being the most probable candidate. The average LP rate acceleration toward an explosion is highly significant prior to the higher energy explosions, supposedly the ones associated with the larger pressure increases. The dramatic decay of the LP activity following explosions, still reinforce the strong relationship between these two processes. We test and we quantify the retrospective forecasting power of these LP rate patterns to predict Ubinas explosions. The prediction quality of the forecasts (e.g. for 17% of alarm time, we predict 63% of Ubinas explosions, with 58% of false alarms) is evaluated using error diagrams. The prediction results are stable and the prediction algorithm validated, i.e. its performance is better than the random guess.