Title
Fluid circulation pattern inside La Soufrière volcano (Guadeloupe) inferred from combined electrical resistivity tomography, self-potential, soil temperature and diffuse degassing measurements
Date Issued
01 November 2014
Access level
open access
Resource Type
journal article
Author(s)
Brothelande E.
Peltier A.
Delcher E.
Komorowski J.C.
Di Gangi F.
Borgogno G.
Passarella M.
Trovato C.
Legendre Y.
Université de la Réunion
Publisher(s)
Elsevier
Abstract
After a drastic decline in 1983, hydrothermal activity at La Soufrière lava dome (Guadeloupe, Lesser Antilles) has been progressively increasing in the summit area since 1992, raising the threat of a renewed eruptive activity. To better constrain the geometry of the hydrothermal system, an extensive high-resolution self-potential survey was performed on the dome and three multi-method profiles combining electrical resistivity tomography, self-potential, ground thermometry and soil CO2 diffuse degassing measurements were carried out to cover its southern periphery in January 2011. Results indicate that hydrothermal ascending flows are currently restricted to a proximal area including the dome and its very vicinity. The extension of hydrothermal alteration inferred from electrical resistivity tomography reflects the presence of a heat source just below the dome. A first-order correction of topography-related self-potential variations allows the identification of major hydrothermal fluid circulations pathways, as well as significant meteoric infiltration zones. Local shifting of hydrothermal fluids towards the dome periphery is favored by the presence of major axes. The regional La Ty fault appears as the major axis draining large volumes of hydrothermal and magmatic fluids. However hydrothermal activity remains confined inside a collapse structure surrounding the dome, that formed in the last 9000years as a result of recurrent edifice collapses, the latest occurring at the onset of the 1530AD eruption. The combination of these qualitative results with structural analysis leads to a synthetic model of magmatic and hydrothermal fluids circulation inside the dome, which may be useful for the assessment of potential hazards associated with a renewal of fluid pressurization, and a possibly associated partial flank-failure.
Start page
105
End page
122
Volume
288
Language
English
OCDE Knowledge area
Geografía social, Geografía económica
Subjects
Scopus EID
2-s2.0-84909949723
Source
Journal of Volcanology and Geothermal Research
ISSN of the container
03770273
Sources of information:
Directorio de Producción Científica
Scopus