2024-03-29T14:05:40Zhttp://digital.csic.es/dspace-oai/requestoai:digital.csic.es:10261/995962018-07-19T11:35:38Zcom_10261_82com_10261_8col_10261_335
urn:hdl:10261/99596
Geophysical exploration on the subsurface geology of La Garrotxa monogenetic volcanic field (NE Iberian Peninsula)
Bolós, Xavier
Barde-Cabusson Stéphanie
Pedrazzi, Dario
Martí Molist, Joan
Casas, Albert
Lovera, R.
Nadal-Sala, Daniel
Monogenetic volcanism
Garrotxa volcanic field
Electrical resistivity tomography
Self-potential
Subsurface geology
Feeding system
We applied self-potential (SP) and electrical resistivity tomography (ERT) to the exploration of the uppermost part of the substrate geology and shallow structure of La Garrotxa monogenetic volcanic field, part of the European Neogene–Quaternary volcanic province. The aim of the study was to improve knowledge of the shallowest part of the feeding system of these monogenetic volcanoes and of its relationship with the subsurface geology. This study complements previous geophysical studies carried out at a less detailed scale and aimed at identifying deeper structures, and together will constitute the basis to establish volcanic susceptibility in La Garrotxa. SP study complemented previous smaller-scale studies and targeted key areas where ERT could be conducted. The main new results include the generation of resistivity models identifying dykes and faults associated with several monogenetic cones. The combined results confirm that shallow tectonics controlling the distribution of the foci of eruptive activity in this volcanic zone mainly correspond to NNW–SSE and accessorily by NNE–SSW Neogene extensional fissures and faults and concretely show the associated magmatic intrusions. These structures coincide with the deeper ones identified in previous studies, and show that previous Alpine tectonic structures played no apparent role in controlling the loci of this volcanism. Moreover, the results obtained show that the changes in eruption dynamics occurring at different vents located at relatively short distances in this volcanic area are controlled by shallow stratigraphical, structural and hydrogeological differences underneath these monogenetic volcanoes.
2014
artículo
International Journal of Earth Sciences : (2014)
1437-3254
http://hdl.handle.net/10261/99596
10.1007/s00531-014-1044-3
1437-3262
eng
http://dx.doi.org/10.1007/s00531-014-1044-3
Sí
info:eu-repo/grantAgreement/EC/FP7/282759
closedAccess
Springer