Inner structure of the Puy de Dôme volcano: cross-comparison of geophysical models (ERT, gravimetry, muon imaging)
- 1Clermont Université, Université Blaise Pascal, Observatoire de Physique du Globe de Clermont-Ferrand, Laboratoire Magmas et Volcans, BP 10118, 63000 Clermont-Ferrand, France
- 2Clermont Université, Université Blaise Pascal, CNRS/IN2P3, Laboratoire de Physique Corpusculaire, BP 10118, 63000 Clermont-Ferrand, France
- 3Centre National de la Recherche Scientifique – UMR6524, LMV, 63038 Clermont-Ferrand, France
- 4Institut de Recherche pour le Développement, R 163, LMV, 63038 Clermont-Ferrand, France
- 5Université de Lyon, Université Lyon 1, CNRS/IN2P3, IPNL, 1 Rue E. Fermi, 69622 Villeurbanne Cedex, France
Abstract. Muon imaging of volcanoes and of geological structures in general is actively being developed by several groups in the world. It has the potential to provide 3-D density distributions with an accuracy of a few percent. At this stage of development, comparisons with established geophysical methods are useful to validate the method. An experiment has been carried out in 2011 and 2012 on a large trachytic dome, the Puy de Dôme volcano, to perform such a comparison of muon imaging with gravimetric tomography and 2-D electrical resistivity tomography. Here, we present the preliminary results for the last two methods.
North–south and east–west resistivity profiles allow us to model the resistivity distribution down to the base of the dome. The modelling of the Bouguer anomaly provides models for the density distribution within the dome that are directly comparable with the results from the muon imaging. Our ultimate goal is to derive a model of the dome using the joint interpretation of all sets of data.