Please use this identifier to cite or link to this item: http://hdl.handle.net/2122/13035
Authors: Tamburello, Giancarlo* 
Moune, Severine* 
Allard, Patrick* 
Venugopal, Swetha* 
Robert, Vincent* 
Rosas-Carbajal, Marina* 
Deroussi, Sebastien* 
Kitou, Gaëtan-Thierry* 
Didier, Tristan* 
Komorowski, Jean-Christophe* 
Beauducel, Jean-Francois* 
DeChabalier, Jean-Batiste* 
Le Marchand, Arnaud* 
Le Friant, Anne* 
Bonifacie, Magalie* 
Dessert, Celine* 
Moretti, Roberto* 
Title: Spatio-Temporal Relationships between Fumarolic Activity, Hydrothermal Fluid Circulation and Geophysical Signals at an Arc Volcano in Degassing Unrest: La Soufrière of Guadeloupe (French West Indies)
Journal: Geosciences 
Series/Report no.: /9 (2019)
Issue Date: 15-Nov-2019
DOI: 10.3390/geosciences9110480
Abstract: Over the past two decades, La Soufrière volcano in Guadeloupe has displayed a growing degassing unrest whose actual source mechanism still remains unclear. Based on new measurements of the chemistry and mass flux of fumarolic gas emissions from the volcano, here we reveal spatio-temporal variations in the degassing features that closely relate to the 3D underground circulation of fumarolic fluids, as imaged by electrical resistivity tomography, and to geodetic-seismic signals recorded over the past two decades. Discrete monthly surveys of gas plumes from the various vents on La Soufrière lava dome, performed with portable MultiGAS analyzers, reveal important differences in the chemical proportions and fluxes of H2O, CO2, H2S, SO2 and H2, which depend on the vent location with respect to the underground circulation of fluids. In particular, the main central vents, though directly connected to the volcano conduit and preferentially surveyed in past decades, display much higher CO2/SO2 and H2S/SO2 ratios than peripheral gas emissions, reflecting greater SO2 scrubbing in the boiling hydrothermal water at 80–100 m depth. Gas fluxes demonstrate an increased bulk degassing of the volcano over the past 10 years, but also a recent spatial shift in fumarolic degassing intensity from the center of the lava dome towards its SE–NE sector and the Breislack fracture. Such a spatial shift is in agreement with both extensometric and seismic evidence of fault widening in this sector due to slow gravitational sliding of the southern dome sector. Our study thus provides an improved framework to monitor and interpret the evolution of gas emissions from La Soufrière in the future and to better forecast hazards from this dangerous andesitic volcano.
Appears in Collections:Article published / in press

Files in This Item:
File Description SizeFormat
Tamburello et al._2019_Geosciences (Switzerland).pdf5.17 MBAdobe PDFView/Open
Show full item record

WEB OF SCIENCETM
Citations

6
checked on Feb 7, 2021

Page view(s)

153
checked on Mar 27, 2024

Download(s)

16
checked on Mar 27, 2024

Google ScholarTM

Check

Altmetric