Options
Dominguez, Lucia
Loading...
4 results
Now showing 1 - 4 of 4
- PublicationRestrictedQuantifying unsteadiness and dynamics of pulsatory volcanic activity(2016)
; ; ; ; ; ; ; ;Dominguez, L. ;Pioli, L. ;Bonadonna, C. ;Connor, C. B. ;Andronico, D.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Catania, Catania, Italia ;Harris, A. J. L. ;Ripepe, M. ; ; ; ;; ;Pulsatory eruptions are marked by a sequence of explosions which can be separated by time intervals ranging from a few seconds to several hours. The quantification of the periodicities associated with these eruptions is essential not only for the comprehension of the mechanisms controlling explosivity, but also for classification purposes. We focus on the dynamics of pulsatory activity and quantify unsteadiness based on the distribution of the repose time intervals between single explosive events in relation to magma properties and eruptive styles. A broad range of pulsatory eruption styles are considered, including Strombolian, violent Strombolian and Vulcanian explosions. We find a general relationship between the median of the observed repose times in eruptive sequences and the viscosity of magma given by eta approximate to 100.t(median). This relationship applies to the complete range of magma viscosities considered in our study (10(2) to 10(9) Pas) regardless of the eruption length, eruptive style and associated plume heights, suggesting that viscosity is the main magma property controlling eruption periodicity. Furthermore, the analysis of the explosive sequences in terms of failure time through statistical survival analysis provides further information: dynamics of pulsatory activity can be successfully described in terms of frequency and regularity of the explosions, quantified based on the log-logistic distribution. A linear relationship is identified between the log-logistic parameters, mu and s. This relationship is useful for quantifying differences among eruptive styles from very frequent and regular mafic events (Strombolian activity) to more sporadic and irregular Vulcanian explosions in silicic systems. The time scale controlled by the parameter mu, as a function of the median of the distribution, can be therefore correlated with the viscosity of magmas; while the complexity of the erupting system, including magma rise rate, degassing and fragmentation efficiency, can be also described based on the log-logistic parameter s, which is found to increase from regular mafic systems to highly variable silicic systems. These results suggest that the periodicity of explosions, quantified in terms of the distribution of repose times, can give fundamental information about the system dynamics and change regularly across eruptive styles (i.e., Strombolian to Vulcanian), allowing for direct comparison and quantification of different types of pulsatory activity during these eruptions. (C) 2016 Elsevier B.V. All rights reserved.100 11 - PublicationOpen AccessIntegrative Post-event Impact Assessment Framework for Volcanic Eruptions: A Disaster Forensic Investigation of the 2011–2012 Eruption of the Cordón Caulle Volcano (Chile)Understanding the complexity of future volcanic impacts that can be potentially induced by the large variability of volcanic hazards and the multiple dimensions of vulnerability of the increasingly interdependent and interconnected societies, requires an in-depth analysis of past events. A structured and inclusive post-event impact assessment framework is proposed and applied for the evaluation of damage and disruption on critical infrastructures caused by the eruption of the Cordón Caulle volcano (Chile) in 2011–2012. This framework is built on the forensic analysis of disasters combined with the techniques of the root cause analysis that converge in a bow-tie tool. It consists of a fault tree connected to subsequent event trees to describe the causal order of impacts. Considering the physical and systemic dimensions of vulnerability, four orders of impact have been identified: i) the first order refers to the physical damage or the primary impact on a component of the critical infrastructure; ii) the second order refers to the loss of functionality in the system due to a physical damage on key components of the system; iii) the third order refers to the systemic impact due to the interdependency and connectivity among different critical infrastructures; and iv) a higher order is related to the consequences on the main economic sectors and to social disruption that can activate an overall damage to the economy of the country or countries affected. Our study in the Argentinian Patagonia shows that the long-lasting impact of the 2011–2012 Cordón Caulle eruption is mostly due to a secondary hazard (i.e., wind remobilisation of ash), which exacerbated the primary impact affecting significantly larger areas and for longer time with respect to primary tephra deposition. In addition, systemic vulnerability, particularly the intrinsic dependencies within and among systems, played a major role in the cascading impact of the analysed communities.
158 34 - PublicationOpen AccessMeMoVolc consensual document: a review of cross-disciplinary approaches to characterizing small explosive magmatic eruptions(2015)
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ;; ; ; ; ; ;; ; ; ; ; ;; ; ; ; ; ; ; ; ; ; ; ;; ; ; ; ; ; ; ; ;; A workshop entitled “Tracking and understanding volcanic emissions through cross37 disciplinary integration: A textural working group.” was held at the Université Blaise Pascal (Clermont-Ferrand, France) on the 6-7th November 2012. This workshop was supported by the European Science Foundation (ESF). The main objective of the workshop was to establish an initial advisory group to begin to define measurements, methods, formats and standards to be applied in the integration of geophysical, physical and textural data collected during volcanic eruptions so as to homogenize procedures to be applied and integrated during both past and ongoing events. The working group comprised a total of 35 scientists from six countries (France, Italy, Great Britain, Germany, Switzerland and Iceland). The group comprised eleven advisors from the textural analysis field, eleven from deposit studies, seven geochemists and six geophysicists. The four main aims were to discuss and define: 1) Standards, precision and measurement protocols for textural analysis; 2) Identify textural, field deposit, chemistry and geophysical parameters that can best be measured and combined; 3) Agree on the best delivery formats so that data can be sheared between, and easily used by, each group; 4) Review multi-disciplinary sampling and measurement routines currently used, and measurement standards applied, by each community. The group agreed that community-wide cross-disciplinary integration, centered on defining those measurements and formats that can be best combined, is an attainable but key global focus. Consequently, we prepared a final document to be used as the foundation for a larger, international textural working group to serve as the basis of fully realizing such a pandisciplinary goal in volcanology. Thus, we here report our initial conclusions and recommendations.605 267 - PublicationRestrictedMeMoVolc report on classification and dynamics of volcanic explosive eruptions(2016-10-28)
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ;Bonadonna, C. ;Cioni, R. ;Costa, A.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Bologna, Bologna, Italia ;Druitt, T. ;Phillips, J. ;Pioli, L. ;Andronico, D.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Catania, Catania, Italia ;Harris, A. ;Scollo, S.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Catania, Catania, Italia ;Bachmann, O. ;Bagheri, G. ;Biass, S. ;Brogi ;Cashman, K. ;Dominguez, L ;Dürig, T. ;Galland, O. ;Giordano, G. ;Gudmundsson, M. ;Hort, M. ;Höskuldsson, A. ;Houghton, B. ;Komorowski, J. C. ;Küppers, U. ;Lacanna, G. ;Le Pennec, J. L. ;Macedonio, G.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione OV, Napoli, Italia ;Manga, M. ;Manzella, I. ;de’ Michieli Vitturi, M. ;Neri, A. ;Pistolesi, M. ;Polacci, M.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Pisa, Pisa, Italia ;Ripepe, M. ;Rossi, E. ;Scheu, B. ;Sulpizio, R. ;Tripoli, B. ;Valade, S. ;Valentine, G. ;Vidal, C. ;Wallenstein, N. ; ;; ; ; ;; ;; ; ;; ; ; ; ; ; ; ; ; ; ; ; ; ; ;; ; ; ; ; ;; ; ; ; ; ; ; ; ;Classifications of volcanic eruptions were first introduced in the early twentieth century mostly based on qualitative observations of eruptive activity, and over time, they have gradually been developed to incorporate more quantitative descriptions of the eruptive products from both deposits and observations of active volcanoes. Progress in physical volcanology, and increased capability in monitoring, measuring and modelling of explosive eruptions, has highlighted shortcomings in the way we classify eruptions and triggered a debate around the need for eruption classification and the advantages and disadvantages of existing classification schemes. Here, we (i) review and assess existing classification schemes, focussing on subaerial eruptions; (ii) summarize the fundamental processes that drive and parameters that characterize explosive volcanism; (iii) identify and prioritize the main research that will improve the understanding, characterization and classification of volcanic eruptions and (iv) provide a roadmap for producing a rational and comprehensive classification scheme. In particular, classification schemes need to be objective-driven and simple enough to permit scientific exchange and promote transfer of knowledge beyond the scientific community. Schemes should be comprehensive and encompass a variety of products, eruptive styles and processes, including for example, lava flows, pyroclastic density currents, gas emissions and cinder cone or caldera formation. Open questions, processes and parameters that need to be addressed and better characterized in order to develop more comprehensive classification schemes and to advance our understanding of volcanic eruptions include conduit processes and dynamics, abrupt transitions in eruption regime, unsteadiness, eruption energy and energy balance.376 12