Assessment, Delineation of Hazard Zones and Modeling of Volcanic Hazards

Despite technological and scientific advances in volcanology, recent eruptions remind us that volcanic events are among the most frequent and destructive natural hazards. This chapter provides a summary of the major hazards and their effects. It details methods of delineation of hazard zones around volcanoes and the methodological evolution over the past 30 years. The chapter provides new modeling approaches and the development of quantitative analyses to improve hazard assessment and risk mitigation. It then considers two classes of volcanic hazards: direct or associated eruptive hazards and post-eruptive hazards. Three major innovations have improved hazard mapping over the last 20 years: the incorporation of numerical or statistical models and simulations; the introduction of the concept of scenario, based on the triple relationship between magnitude, frequency and intensity; and the more recent consideration of the impacts of specific processes on the habitat and infrastructures whose geotechnical characteristics are defined.