91412 - Volcanic Hazards and Environmental Impact

Learning outcomes

Volcanism is one of the most dramatic and rapid agent of geologic change. Even though less frequent and devastating than earthquakes, any kind of volcano can produce hazardous or deadly phenomena, whether during an eruption or in quiescence conditions, thus inducing risks for densely populated areas around the world. Some eruptions can have a meaningful global impact on Earth’s climate, either with cooling or warming effects, through the ejection of large amounts of ash particles and gases into the atmosphere. Understanding the eruptive behaviour of a volcano is the first step in mitigating volcanic hazards (and risk), eventually taking into consideration some elements of unpredictability inherent to these natural systems. At the end of the course, students will acquire knowledge on the main eruptive processes (lava flows, explosive eruptions, volcano-tectonic collapses, lahars) and their effects on persons, properties and resources and the environment, with a particular focus on the eruptive phenomena that can potentially affect (global) climate changes (ash dispersal, gas emission). Moreover, students will learn about the main parameters for the monitoring of volcanoes, i.e. deformation of the soil, seismicity, and fluid geochemistry, particularly implementing the monitoring techniques based on gas emission in volcanic-hyrothermal systems by means of laboratory experiments on analytical methods. Laboratory activities will also concern the most important models used for volcanic hazards and risk assessment and the mathematical and statistical methods for processing data in terms of volcanic plume dynamics and atmospheric transport of volcanic ash, gravity-driven phenomena (lava flows, pyroclastic currents and lahars) and dispersal of volcanic and hydrothermal gases into the air. The course will be integrated by a field excursion in Italian active volcanic areas (Etna, Stromboli, Vulcano, Vesuvius and Campi Flegrei), including visits to volcanic observatories and seminars of researchers from other institutions about their monitoring.

Course contents

The course is arranged into different sections aimed at providing a general framework of knowledge on eruptive activity starting from its magmatic sources to the volcanic edifices on surface, and at defining the main eruption types and depositional mechanisms of the various eruptive processes with a special outcome on the evaluation of the different volcanic hazards and risks. I – Physical properties of magmas. Magma chambers, dykes and eruptive conduits. II – Explosive volcanism. Classification of volcanic activity and eruption types. Magmatic fragmentation. Eruptive plumes and fall deposits. Pyroclastic density currents and their deposits. III - Effusive volcanism. Features and flow dynamics of mafic lava flows (pahoehoe and aa). Features and flow dynamics of silicic lavas: blocky lava flows, rhyolitic lava flows (coulees), lava domes. IV - Volcano-tectonic collapses (calderas and sector collapses). Post-eruption mass gravity flows (debris avalanches, lahar). V - Eruption forecast. Volcanic hazard maps. Volcano monitoring. Risk mitigation in volcanic areas. The course will take into account the most famous eruptions in the history of volcanology and recent examples as study cases of hazard evaluation and risk mitigation. A part of the course will be dedicated to a flipped-learning exercise during which the teachers will propose case studies that the students, in small groups, will have to analyze and study, identifying specific aspects and possible interpretations, then presenting to the rest of the class what achieved, discussing the main aspects together with the other students and teachers. A field excursion in Italian active volcanic areas (Etna, Stromboli, Vulcano, Vesuvius and Campi Flegrei) will complete the course, including also visits to volcanic observatories and monitoring centres.

Teacher in charge: Prof. Federico Lucchi

Collaborator teacher: Dott.Matteo Roverato

The course is organized into 32 hours of frontal lessons (4 CFU), and 12 hours of field activity (2 CFU)

Readings/Bibliography

Power Point lecture notes.

• H.U. Schminke, 2004. Volcanism. Springer-Verlag, Berlin Heidelberg

• H. Sigurdsson (Ed.), 2015. Encyclopedia of Volcanoes. Accademic press, San Diego, U.S.A.

Teaching methods

PowerPoint presentations

Flipped-learning activity

Field excursion aimed at verifying the learning of the concepts treated during the room lectures

In consideration of the types of activities and teaching methods adopted, the attendance of this course requires all students to carry out modules 1 and 2 in e-learning [https://www.unibo.it/it/servizi- e-opportunities / health-and-assistance / health-and-safety / safety-and-health-in-places-of-study-and-training] and participation in module 3 of specific training on safety and health in places of study. Information on dates and methods of attendance of module 3 can be consulted in the specific section of the degree program website. Moreover, the students will have to undergo a medical eligibiity examination.

Assessment methods

The assessment is aimed at verifying the knowledge of the student about the main aspects of volcanology, and the ability of putting together the theory knowledge and data derived from the field excursion.

The exam can be oral or written (by agreement with the teachers).

Teaching tools

Video-projector.

Hand samples.

Office hours

See the website of Federico Lucchi

See the website of Matteo Roverato