6-6-6-6-6-6-6-6-6-6-6-6-6-6-6-6-6-6 From: cristianmontanaro@xxxxxxxxx 6-6-6-6-6-6-6-6-6-6-6-6-6-6-6-6-6-6 Dear All, We would like to draw your attention to the session â??V03 â?? Phreatic and hydrothermal eruptions: what we really know about triggers, magnitude, styles and hazardsâ?? proposed in the context of the 27th IUGG General Assembly, which will be held on July 8-18, 2019 at the Palais des Congrès in Montréal, Québec, Canada ( http://iugg2019montreal.com/abstract-submission.html). This session invites a broad range of disciplines (from field geological observations to geophysical and geochemical monitoring, from physical modelling to laboratory experiments and numerical simulation) to discuss our current state of knowledge on steam-driven eruptions (phreatic and hydrothermal eruptions) and discuss future research directions. The deadline for the abstract submission is *February 18, 2019*. Hoping the initiative will meet your favor, we look forward to receiving your contribution. Sincerely yours, Cristian, Bettina, Corentin and Shaul **V03 â?? Phreatic and hydrothermal eruptions: what we really know about triggers, magnitude, styles and hazards** Convener: Cristian Montanaro (New Zealand) Co-Conveners: Bettina Scheu (Germany), Corentin Caudron (Singapore), Shaul Hurwitz (USA) Description Hydrothermal or phreatic eruptions, alias steam-driven (non-magmatic) explosive events, are frequent phenomena occurring at active volcanoes, within geothermal areas and in rather pristine environments, e.g. heralding magmatic/phreatomagmatic eruptions. Circulating hydrothermal fluids may promote both pore pressure augmentation and alteration of the host-rock, with the latter process affecting the rock petrophysical properties (e.g. porosity, permeability strength). Pressure and temperature perturbations (e.g. magmatic fluids injection or landslides) may result in the near-instantaneous vaporization of pressurised hot fluids (especially water) trapped in pores and cracks within the upper parts of shallow hydrothermal system. The flashing/expansion of fluids blasts rock apart and ejects it upward and outward developing gas and mixed gas-liquid jets, pyroclastic density currents and lateral blasts, often accompanied by intense ballistic showers. These phenomena, whose violence depends on the explosivity of the fluids driving them, and on the petrophysical properties of the host-rocks, pose serious threats in areas increasingly exploited for tourism and geothermal power, or within populated areas. Due to the complex and still largely unknown interaction of the magmatic and hydrothermal systems, steam-driven eruptions are among the most sudden and unpredictable volcanic phenomena. Incomplete or missing stratigraphic records, limited understanding of explosive failure processes, absent or unclear precursors in geophysical and geochemical signals, all result in the lack of reliable scientific models to forecast locations, triggering, and magnitude of phreatic and hydrothermal eruptions. This symposium invites contributions from a broad range of disciplines (from field geological observations to geophysical and geochemical monitoring, from physical modelling to laboratory experiments and numerical simulation) on phreatic and hydrothermal eruptions, including reports and lessons learned from recent events, to summarize our current state of knowledge on steam-driven eruptions and discuss future research directions. ============================================================== Volcano Listserv is a collaborative venture among Arizona State University (ASU), Portland State University (PSU), the Global Volcanism Program (GVP) of the Smithsonian Institution's National Museum of Natural History, and the International Association for Volcanology and Chemistry of the Earth's Interior (IAVCEI). ASU - http://www.asu.edu/ PSU - http://pdx.edu/ GVP - http://www.volcano.si.edu/ IAVCEI - http://www.iavcei.org/ To unsubscribe from the volcano list, send the message: signoff volcano to: listserv@xxxxxxx, or write to: volcano-request@xxxxxxx. To contribute to the volcano list, send your message to: volcano@xxxxxxx. Please do not send attachments. ============================================================== ------------------------------
