viernes, 11 de noviembre de 2011

Volcano Observatory Best Practice in Argentina

Volcano Observatory Best Practice Workshop
 - Near Term Eruption Forecasting
Erice, Sicily (IT), 11 - 15 September 2011

Lessons learned from recent volcanic activity in Argentina

Elizabeth I. Rovere1, Lía I. Botto2, María E. Canafoglia3, Mónica Rabolli4, Gloria Pujol5, Roberto A. Violante6

1SEGEMAR, Dir. Geología Regional. Av. Julio A. Roca 651, 10º Piso (C1067ABB) Buenos Aires, Argentina.  Email: eirovere
2Cequinor. Centro de Química Inorgánica F.C.E.U.N.L.P. Av. 47 y 115 C.C.962-1900 La Plata, Argentina.
3Facultad de Ciencias Naturales y Museo, U.N.L.P.  Av. 60 y 122, La Plata, Argentina.
4CONAE, Comisión Nacional de Actividades Espaciales. Av. Paseo Colón 751 (1063) Buenos Aires, Argentina.
5Servicio Meteorológico Nacional, Ministerio de Defensa. 25 de Mayo 658, Buenos Aires,  Argentina.
6Servicio de Hidrografía Naval. Av. Montes de Oca 2124 (C1270ABV) Buenos Aires, Argentina.

Recent Andean historical eruptions reflect the increasing tendency of eruption frequencies and northward displacement along the Liquiñe-Ofqui fault zone, gradually closer to the concentration of large cities. Argentina has a long history of human and environmental impact by volcanic activity, because of its territorial location, downwind Southern and Central Andes where 138 volcanoes are active. Most of them are in Chile cordillera, ash and pyroclastic products are transported eastward by predominant winds (the Westerlies). Therefore ash fall is the main volcanic hazard in Argentina. Ashes (and altered products such as zeolites and bentonites) constitute more than 70% of Argentine soils, considered as one of the richest worldwide. Recent examples of hazardous eruptions are synthesized as an approach to the problem. In 1991 Hudson volcano ash plumes affected most of Patagonia population and breeding cattle with huge economical losses (e.g. Los Antiguos). During 2000, Copahue volcano started a phreatomagmatic eruption, ash fall, lahars and PF hazarded the population of Caviahue village (distant 8 Km from the active crater, inside the inner rim of Del Agrio Caldera). Far from any explanation, over 50 houses and hotels were built since then, accompanied by intense ski tours promotions. In 2008, Chaitén volcano started an eruption (VEI 4) and extruded a volume of tephra of >1.7 x 108 m3. In Chaiten town (Chile) a destructive lahar forced the action of the ONEMI (Chile) to evacuate over 4500 people in 72 hours. Fine grained ash fall (high silica -cristobalite-) produce long term health hazard which effects are not well known yet. A special attention is needed to attend children´s health in vulnerable mountainside populations. Recently, in June 2011 Puyehue - Cordón del Caulle fissure eruptions and ash plumes produced impact in large cities, Bariloche was covered by ash, and plumes reached Buenos Aires (1500 Km eastward) forcing closures of local and international airports, for weeks.
Our purpose is to increase the acceptance of research projects including tephrology (EDS–SEM, geochemistry, sedimentology, mathematical dispersal models, hazard mapping, etc.), also a fluent network interaction between Chile and Argentina volcanic organizations. Furthermore, an international communication is necessary to coordinate not only emergencies but preventive volcano monitoring systems and post-eruption social relegation, usually resulting in self-evacuations and/or psychological depression. The mentioned examples allow us to conclude that the Andean region is one of the examples to prioritize best practices organizative centers focused on public health; 1) prevention, 2) planning and 3) scientific support. A Volcanic Observatory in Argentina through these 3 points: will center the database, immediate report, open information to communities, perform decisions and create synergy and interaction among scientific institutions, authorities and vulnerable communities.