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long-term hazard assessmen volcanic field azard assessment on
XIV Reunión Nacional de Cuaternario, Granada 2015 LONG-TERM TERM HAZARD ASSESSMENT ON QUATERNARY MONOGENETIC VOLCANIC FIELDS USING E E-TOOLS L. Becerril (1), S. Bartolini (1), J. Martí (1), A. Geyer (1) (1) Group of Volcanology, SIMGEO (UB (UB-CSIC), Institute of Earth Sciences Jaume Almera, CSIC. C/ Lluis Solé I Sabaris s/n. 08028-Barcelona, Barcelona, Spain. [email protected]; [email protected]; [email protected]; [email protected] Abstract (Evaluación Evaluación de la peligrosidad a largo plazo en campos volcánicos monogenéticos cuaternarios utilizando etools): Los campos volcánicos monogenéticos se caracterizan normalmente por tener una gran dispersión del volcanismo y una baja frecuencia eruptiva, lo cual dificulta la evaluación de la peligrosidad volcánica en ellos. El Grupo de Vulcanología de Barcelona (GVB) ha comenzado a desarrollar una metodología y una serie de herramientas (QVAST, HASSET, VORIS) para la evaluación de la peligrosidad volcánica volcánica, las cuales han sido aplicadas con éxito a campos cuaternarios monogenéticos como La Garrotxa, El Hierro o Decepción. En el marco del nuevo proyecto VeTOOLS se está llevando a cabo el desarrollo de nuevas herramientas para la evaluación de la peligrosidad y del riesgo volcánico en otras islas volcánicas oceánicas. Con este proyecto se pretende facilitar la cooperación entre científicos y organismos de protección civil con el fin de intercambiar y unificar metodologías y tecnologías para reducir los impactos de las futuras erupciones. Key words: Volcanic Hazard, e-tools, tools, monogenetic fields, VeTools Project Palabras clave: Peligrosidad Volcánica, e e-tools, campos monogenéticos, Proyecto VeTools INTRODUCTION Monogenetic volcanic fields are the most common volcano type on Earth. Most of these areas are characterised by low frequent activity, therefore they sometimes are regarded as not potentially dangerous and often as non-active active zones. These facts, together with they are also characterised by randomness on the spatio-temporal temporal evolution of their volcanic centres, make ke difficult to forecast the probability of occurrence of future eruptions, that is, to assess the volcanic hazard in these areas. The Group of Volcanology of Barcelona (GVB (GVB, http://www.gvb-csic.es/)) has started devel developing a systematic methodology to evaluate the volcanic hazard in different volcanological settings through the development and use of e-tools tools integrated in a Geographic Information System (GIS) (GIS). Currently we are creating an integrated software platform sp specially designed to assess and manage volcanic risk, called VolcanBox. This platform contains user user-friendly free e-tools tools specifically addressed to long long- and short-term hazard assessment, vulnerability analysis, decision decisionmaking, and volcanic risk management that are being developed in the frame of VeTools project (funded by European Commission - Humanitarian Aid and Civil Protection Service tools).. This project will facilitate interaction and cooperation between scientists and Civil Protection Agencies in order der to share, unify, and exchange procedures, methodologies and technologies to effectively reduce the impacts of volcanic disasters by improving assessment and management of volcanic risk. Here we present the methodology and the application of several e-tools tools such as QVAST (spatial probability), HASSET (temporal probability) and VORIS (eruptive scenarios) to perform long long-term volcanic hazard assessment in three different quaternary monogenetic volcanic fields: La Garrotxa Volcanic Field (Catalonia, Spain), n), El Hierro Island (Canary Islands, Spain), and Deception Island (South Shetland Islands, Antarctica). STUDY AREAS Spain is a monogenetic La Garrotxa (Catalonia,, Spain) volcanic field that contains over 50 cones ranging in age 0.7 Ma - early Holocene (Fig. 1). It is a densely populated industrial area and has an international airport. This volcanic field has not been officially considered as an active volcanic area until 2013 due to its last eruption was 11--13 ky ago. Nevertheless it has a considerable potenti otential for future eruptions and a volcanic hazard assessment has been conducted. El Hierro Island (Canary Islands, Spain), is the emergent summit of a volcanic vo shield which rises about 5,500 m from its submarine base at a depth of ~3,900 m b.s.l. (Fig. 1). It is the most recent active island of the Canaries with 1.12 Ma in age (Guillou et al., 1996). It hosted its last eruption in 2011-2012, 2011 that had a serious negative impact on the tourism and on its local economy. This eruption highlighted the need to perform m volcanic hazard studies on the island and also in the rest of the Canary archipelago. Deception Island (South Shetland Islands, Islands Antarctica) is a composite volcanic system truncated by a large central collapse caldera that is < 0.75 Ma (Fig. 1). There have been more than 20 eruptions in the past two centuries that have been well documented. In spite of it is an inhabited area, it hosts scientific bases that were destroyed or hardly damaged in the lasts eruptions. eruptions New eruptions on the island could seriously affect scientists and tourists since the number of visitors has increased since 1966. This fact together with there was enough quality data to test the methodology there, there prompted us to develop the volcanic canic hazard assessment in this island. METHODOLOGY Long-term term volcanic hazard assessment is necessary to know how the next eruption could be. It is based on the past history of the volcano and the information needed comes from the geological record. Long-term Long assessment is estimated from years to decades, where the main source of information is mainly XIV Reunión Nacional de Cuaternario, Granada 2015 After a good understanding of the past eruptive history of the volcanic area that tell us how next eruptions could be, the following step on the volcanic hazard assessment consists of evaluating the likelihood of a future eruption, which will provide an indication of which areas are the most likely to host future vents (Martí and Felpeto, 2010). QVAST (Bartolini et al., 2013a)) has been the e-tool e used to evaluate the long-tern tern spatial probability of vent opening (Where). It mainly uses structural data such as vents,, dykes, faults, fractures and eruptive fissurefissure alignments obtained from geological and geophysical studies. The next step corresponds to the temporal probability estimation of any possible volcanic event. Long-term Long forecasting is based on historical and geological data, as well as on theoretical models, and refers to the time window available before an unrest episode occurs in the volcanic system. The e-tool e HASSET (Sobradelo et al., 2014) has allowed evaluating the temporal probability (When) of any possible poss volcanic scenario. Once spatial and temporal probabilities are estimated, the next step forward consists of simulating several scenarios for evaluating the potential extent of the main expected hazards. Most of these studies are based on simulation models m implemented on Geographical Information Systems (GIS) that allow modelling volcanic processes such as lava flows, PDCs and ash fallout. VORIS (Felpeto et al., 2007) has been the e-tool tool used for developing volcanic scenarios. The last step in a long-term term volcanic hazard evaluation consist of developing volcanic hazard maps that can represent one of the bastions of risk assessment and can be required for land-use land planning and for developing emergency plans. CURRENT AND FUTURE EXPECTED RESULTS We have started applying some of these free e-tools e for the long-term term volcanic hazard assessment on La Garrotxa Volcanic Field, El Hierro, Hierro and Deception Islands with very valuable results (Bartolini et al., 2013, 2014, 2015; Becerril et al., 2013, 2014). 2014) Fig. 1: Geographical location of the three monogenetic volcanic fields where volcanic hazard assessment has been conducted. 1) La Garrotxa Volcanic Field; 2) El Hierro Island; 3) Deception Island. structural data from past eruptions. Different steps need to be followed sequentially in any long long-term volcanic hazard assessment. They are: 1) the characterisation of past volcanism in the study area (How?); 2) the analysis of the volcanic susceptibility (Where?); 3) the estimation of temporal probabilities (When?); 4) the simulation of the most probable eruptive scenarios such as lava flows, pyroclastic fallout and pyroclastic density currents (PDCs); and 5) the assessment of the volcanic hazard. We have obtained the spatial probability maps of these three areas that have been the basis on the evaluation of the temporal probabilities and on the construction of the different volcanic scenarios related to lava flows, PDCs and fallout (Fig. (Fig 2). The end result through the combination of the most probable scenarios represents the first qualitative integrated volcanic hazard maps map of these volcanic areas (Fig. 2). Our purpose is to apply all the previous developed and the new e-tools tools on other volcanic oceanic islands as they represent highly vulnerable natural and socioeconomic systems. Some of them are going to be the eastern Atlantic volcanic islands (Canaries, Açores, and Iceland), which cover a wide range of volcanological and socioeconomic scenarios, with the th aim of exporting the results obtained to the other European volcanic islands, but also to the continental active volcanic regions. XIV Reunión Nacional de Cuaternario, Granada 2015 Fig. 2: Methodology used and results obtained using e e-tools for the long-term term volcanic hazard assessment on Deception Island. For more information see Bartolini et al., 2013, 2014, 2015 and Becerril et al., 2013, 2014. Acknowledgements: VeTools is a project financially supported by the European uropean Commission. EC ECHO project SI.2.695524 (VeTOOLS) 2015-2016. References Bartolini, S., Cappello, A., Martí, J., Del Negro, C. (2013). QVAST: A new Quantum GIS plugin for estimating volcanic susceptibility. Natural Hazards and Earth System Sciences, 13(11), 3031--3042. Bartolini, S., Geyer, A., Martí, J., Pedrazzi, D., Aguirre AguirreDíaz., G. (2014). Volcanic hazard on Deception Island (South Shetland Islands, Antarctica). Journal of Volcanology and Geothermal Research Research, 285, 150-168. Bartolini, S., Bolós, X., Martí, J., Riera Riera-Pedra, E., Planagumá, Ll. (2015). Hazard assessment at the Quaternary La Garrotxa Volcanic Field (NE Iberia). Natural Hazards, DOI: 10.1007/s11069 10.1007/s11069-015-1774-y. Becerril, L., Cappello, A., Galindo, I.,, Neri, M., Del Negro, C. (2013). Spatial probability distribution of future volcanic eruptions at El Hierro Island (Canary Islands, Spain). Journal of Volcanology and Geothermal Research, 257, 21‐‐30. Becerril, L., Bartolini, S., Sobradelo, R., Martí, J., Morales, J.M., Galindo, I. (2014). Long‐term term volcanic hazard assessment on El Hierro (Canary Canary Islands). Natural Hazards and Earth System Sciences Sciences, 2, 1799‐1835. Guillou, H., Carracedo, J.C., Pérez‐Torrado, Torrado, F.J., Rodríguez Badiola, E.R. (1996). K‐Ar Ar ages and magnetic stratigraphy of a hotspot‐induced, hotspot fast grown oceanic island: El Hierro, Canary Islands. Journal of Volcanology and Geothermal Research, Research 73, 141‐155. Felpeto, A., Martí, J., Ortiz, R. (2007). Automatic GIS‐based system for volcanic hazard assessment. Journal of Volcanology and Geothermal Research, Research 166, 106‐116. Martí, J. and Felpeto, A. (2010). Methodology for the computation of volcanic susceptibility: Application to Tenerife Island (Canary Islands). Journal of Volcanology and Geothermal Research, Research 195, 69-77. Sobradelo, R., Bartolini, S., Martí, J. (2014). HASSET: HASSE a probability event tree tool to valuate future volcanic scenarios using Bayesian inference presented as a plugin for QGIS. Bulletin ulletin of Vocanology, Vocanology 76, 770.
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