Risk Assessment and Mitigation at Copahue Volcano

Abstract

Abstract"Risk assessment" is a relatively new concept in Argentina, since the very first hazard map was only recently constructed on the basis of the 1992 eruption of Copahue volcano (Patagonia). Copahue is considered a very active volcanic system since 13 eruptive events have been recognized over the last 260 years. Most the events are phreatic and phreato-magmatic with VEI ≤ 2; nevertheless such eruptions represent a threat for the communities living in the surrounding areas of the emission centre, not only because of pyroclastic flows and tephra fall (the nearby villages, Caviahue and Copahue, have so far only experienced ash fallout), but also due to the possible formation of mud flows and flank collapse triggered by the volcanic activity. Owing to the frequent eruptions of Copahue, the most recent ones (2000, 2012) showed an increasing explosive character, hazard survey actions, such as thematic maps and contingency plans are constantly, though slowly, modified. The risk assessment described in this chapter calls for the implementation of the monitoring network in the Argentina side of the volcano, since the only currently active seismic stations (OVDAS) are located in the Chilean side of the volcanic edifice, Copahue volcano lying at the border between the two countries. Moreover, the Chilean observatory adopts criteria of alert levels, which

Environmental challenge of landslide in geothermal areas: an introductory study

“…Another proactive mitigation measure can be taken by adopting non-structural mitigation for the locals as a contingency plan to safeguard the community [48,69]. It is to develop an integrated system between the monitoring instruments and public warning, with social education on living with landslide hazards [72], and to compensate the community if unfortunate events occur.…”

AMS and rock magnetism in the Caviahue-Copahue Volcanic Complex (Southern Andes): emission center, flow dynamics, and implications to the emplacement of non-welded PDCs

“…In the SVZ, the magmatic activity occurs as a result of the subduction of the Nazca Plate under the South American Plate, with extensive volcanism of basaltic to andesitic composition (Hildreth and Moorbath, 1988;Stern, 2004). In this context, the CCVC composes one of the most active volcanic centers in the Andean belt, with several eruptive events in the last century (Caselli et al, 2016;Tassi et al, 2016). The particular setting of the CCVC attracted several studies in the recent decades, with a broad range of topics including geomorphology (e.g., Díaz, 2003;Báez et al, 2020a), geochemistry (e.g., Mazzoni and Licitra, 2000;Melnick et al, 2006;Varekamp et al, 2006), geochronology (e.g., Pesce, 1989;Melnicik et al, 2006) structural (e.g., Melnick et al, 2006;Velez et al, 2011;Folguera et al, 2016), geothermal (e.g., Barcelona et al, 2019), and AMS and paleomagnetism (e.g., Ort et al, 2014;Moncinhatto et al, 2019Moncinhatto et al, , 2020.…”

“…Located in the southern Andes (between Argentina and Chile), the CCVC (Fig. 1) comprises one of the most active volcanic centers in this orogenic segment (Caselli et al, 2016;Tassi et al, 2016). Despite the young age (< 5 Ma, Linares et al, 1999), CCVC deposits were strongly affected by Pleistocene glaciations (Díaz, 2003;Varekamp et al, 2006;Báez et al, 2020a), leading to a fragmented record and establishing a geologic puzzle, especially in the case of the more friable, volcaniclastic deposits.…”

An analysis of volcanic SO2 and ash emissions from Copahue volcano

“…Most events are phreatic and phreato-magmatic with low explosive character; nevertheless, such eruptions represent a threat for the communities living in the areas surrounding the emission center. (Caselli et al, 2016a(Caselli et al, , 2016b(Caselli et al, , 2016c. Moreover, increasing urban development implies that even relatively small phreatomagmatic explosions could cause substantial economic losses and put lives at risk (Caselli et al, 2016a).…”

“…Argentine villages, Caviahue and Copahue (Fig. 1), have so far only experienced ash fallout and gasses emissions, but are also at risk because of possible mudflows and flank collapse triggered by volcanic activity (Bermúdez and Delpino, 1995;Caselli et al, 2016b).…”