EGU21-4889
https://doi.org/10.5194/egusphere-egu21-4889
EGU General Assembly 2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.

Modelling gas dispersal phenomena at La Soufrière volcano (Guadeloupe, Lesser Antilles)

Silvia Massaro1, Fabio Dioguardi2, Laura Sandri1, Giancarlo Tamburello1, Jacopo Selva1, Sèverine Moune3,4, David Jessop3,4, Roberto Moretti3,4, Jean-Christophe Komorowski3, and Antonio Costa1
Silvia Massaro et al.
  • 1Istituto Nazionale di Geofisica e Vulcanologia, Sezione di Bologna, Italy (silvia.massaro@ingv.it)
  • 2British Geological Survey, The Lyell Centre, Edinburgh, UK
  • 3Observatorie Volcanologique et Sismologique de Guadeloupe, Institut de Physique du Globe de Paris, Gourbeyre, Guadeloupe
  • 4Universitè Clermont Auvergne, CNRS, IRD, OPGC Laboratoire Magmas et Volcans, Clermont-Ferrand, France

In recent decades, reliable computational models have significantly advanced, and now represent a valuable tool to make quantitative and testable predictions, supporting gas dispersal forecasting and hazard assessments for public safety. In this study, we carried out a number of tests aimed to validate the modelling of gas dispersal at La Soufrière de Guadeloupe volcano (Lesser Antilles), which has shown quasi-permanent degassing of low-temperature hydrothermal nature since its last magmatic eruption in 1530 AD. In particular, we focused on the distribution of CO2 and H2S discharged from the three main present-day fumarolic sources at the summit, using the MultiGAS measurements of continuous gas concentrations collected during March-April 2017. We implemented the open-source Eulerian code DISGAS-2.0 for passive gas dispersion coupled with the mass consistent Diagnostic Wind Model (DWM), using wind measurements and atmospheric stability information from a local meteorological station and the ECMWF-ERA5 reanalysis data. We found that model outputs are highly dependent on the resolution of the topographic data, which affect mainly the reliability of DWM meteorological fields, especially on and around the steep dome. Our results satisfactory reproduce the observed data, indicating the potential usefulness of DISGAS-2.0 as a tool for quantifying gas hazard and reproducing the fumarolic degassing and at La Soufrière de Guadeloupe.

 

How to cite: Massaro, S., Dioguardi, F., Sandri, L., Tamburello, G., Selva, J., Moune, S., Jessop, D., Moretti, R., Komorowski, J.-C., and Costa, A.: Modelling gas dispersal phenomena at La Soufrière volcano (Guadeloupe, Lesser Antilles), EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-4889, https://doi.org/10.5194/egusphere-egu21-4889, 2021.

Corresponding presentation materials formerly uploaded have been withdrawn.