About Earth Sciences... 
"In theory, theory and practice are the same. In practice, they are not." Albert Einstein.
"Under the most rigorously controlled conditions of pressure,
temperature, volume, humidity, and other variables, the Earth will do
as it damns well pleases." Harvard Law.
"Only God knows - if He knows! - the real Earth model." Albert Tarantola [1949-2009].
Objectives and Strategy
Subject: From deformation field measurement to the edifice structures and eruptive process dynamics
Monitoring of active volcanoes have to be based on
real time observations and a dynamic quantitative model which helps to
interpret them. This model is constructed from fundamental studies of
mechanical behaviour, structures, magma dynamics and regional tectonic
context, allowing also to go deeper into our knowledge of the volcanic
system and its evolution.
Basic principles of magma and gas phenomenology start to be well understood [Jaupart, 1994; Neri and Macedonio,
1996]. On the other hand, direction of explosions, lava domes
collapses, and the involved volumes during eruptions, still remain
difficult to predict, while they are mandatory for volcanic risk
evaluation. Indeed, numerical models need initial and boundary
conditions, common to the magma dynamics and the mechanics of the
volcano. This concerns as well physical and chemical characteristics of
the source than the structure of the volcano: geometry of the magma
chamber and conduit, fractures, topography and mechanical properties of
the medium. These conditions are specific to each volcano and change
with time. They presently have been estimated for a dozen of the 600
world active volcanoes. To participate in this domain, I propose two
complementary axes of rechearch:
- A study of substructures and mechanical behaviour of some
selected volcanoes (because of monitoring obligations or for
experimental studies) through a numerical analysis of deformation field;
- A quantitative study of magma flux and mass budget of eruptions,
from the integration of various geophysical results allowing
calculation of source characteristics then boundary conditions of the
problem; essentially from surface imaging, seismology (tomography and
sources), gravimetry, geochimia, hydrodynamics and electromagnetism.
These two studies are based on precise observations.
Regarding the desired precision and the complexity of involved
phenomena, the multiparameter approach seems to be the once allowing a
true validation of measured signals. I propose two additional
methodological approaches:
- Integration and systematic validation of different types of
observations, complementary and/or redundant, to analyse possible
artefacts (sites effects, meteorological influences), and estimate a
"realistic" uncertainty on measurements;
- Elaboration of inverse processes adapted to the data complexity,
in order to always estimate a probability for the used modelling.
This should lead to the possibility of determining
more quantitative models of eruptive processings, then (I hope) will
help the volcanic hazard mitigation.
Main Geophysical Results
Volcanoes:
- Merapi, Indonesia: Contribution
to the knowledge of shallow structures (role of fractures at summit,
magma conduit) and deep structures (localisation of a magma chamber),
of characteristics of involved sources of deformation (magma flux
variations, lava dome weight and mass budget) and the mechanical
behaviour of the edifice (estimation of elasticity modulus at large
scale, precise localisation of a rock slope problem) [Beauducel, 1998; Beauducel and Cornet, 1999; Beauducel et al., 2000a; Beauducel et al., 2006].
We have also formed indonesian teams to GPS technique between 1993 and
1997, such that since 1998, they carry on GPS network measurements
twice a year, process and interpret the data at VSI.
- Etna, Italy: Joint modelling of tropospheric delay and
deformations from SAR images ERS-1, showing that large scale observed
signal from 1992 to 1998 is mostly due to atmospheric artefact [Beauducel et al., 2000b; Briole et al., 1999].
- Campi Flegrei, Italy: Evidence for complex 3-D geometry of
the caldera discontinuity (levelling and gravimetric data during the
1983-1985 bradyseism) and 1993-1996 large scale subsidence (InSAR) [Avallone et al., 1999; Beauducel and De Natale, 2004].
- Piton de la Fournaise, Réunion: "Tiltmeter antenna" instrumentation and data processing: analysis of site effects, real-time dyke intrusion characterisation. [Beauducel, 1992].
- Soufrière, Guadeloupe: Hydrothermal system
characterization and modelling : 3-D modelling of lava dome large
fractures deformations from extensometer data, consistent with
superficial pressure source [Jacob et al., 2005], evidence for rock alteration layer from electrical tomography measurements [Nicollin et al., 2006], quantification of acid gas in the fumaroles [Bernard et al., 2006].
Methodology:
- Monitoring: Development of a new integrated monitoring
system interface for volcano observatories, pluridisciplinary and
real-time tools to help scientific interpretation during crisis [Beauducel et al., 2004].
- GPS: Development of a kinematic / static combination (measurement and adjustment protocols) for rapid and precise survey [Beauducel et al., 2006].
- Tiltmetry: Application of a low-cost method for
high-precision tilt surface installation that avoids main
thermomechanical and rainfall effects; signal processing methods for
correction of noise in continuous tilt data [Beauducel, 1998; Beauducel and Cornet, 1999].
- SAR Interferometry: Constitution of a high-precision
coherency map (permanent scatters); pixel quality automatic selection
for further processing (masks); analyse of tropospheric delay by
phase-elevation relation; notion of interferogram compensation by
inversion [Beauducel et al., 2000b; Briole et al., 1999].
- Modelling: Evidence for a striking relation between
seismic events and long-term deformation; evidence for 3-D local
effects in mechanical models; integration of various data to determine
a unique deformation field [Beauducel et al., 2000a; Beauducel and Cornet, 1999].
Projects Participation
On-Going Projects:
- DOMERAPI (ANR ISTERRE/ISTO/LMV/IPGP/CVGHM/IRD) : Dynamics of an arc volcano with extruding lava domes, Merapi (Indonesia): from the magma reservoir to eruptive processes. Date: 2013-2016
- EDAS (ORB LGI): Environmental Data Acquisition System, consulting and software development. Advisor: Michel Van Ruymbeke. Date: since 1991.
Past Projects:
- DOMOSCAN (ANR LGIT/IPGP/Gésciences Rennes/UAG) : Quantification de la dynamique et suivi spatio-temporel du système hydrothermal de la Soufrière de Guadeloupe. Date: 2009-2012
- ACI Soufrière (INSU-CNRS) : Structure and dynamic of the hydrothermal system at Soufrière of Guadeloupe lava dome. Date: 2003-2006.
- Étude du risque tsunami en Guadeloupe (MOM) : Installation de marégraphes permanents pour l’analyse des effets liés à l’activité volcanique. Date: since 2003.
- French-Indonesian cooperation in volcanology: Formation of
indonesian technicians, engineers and students on geodetic technics
(field work and data processing); technical consulting for the french
experts at VSI - MVO; and research & budget projects definition. Advisors: Georges Poupinet, Michel Diament, François-Henri Cornet. Date: since 1994.
- EMEWS (DGXII ENV4-98-0728): European Mobile Early Warning System. Advisor: Pierre Briole.
- PRE-ERUPT (DGXII ENV4-CT96-0259):
Modelling and parameterization of pre-eruptive processes, sub-project
“Interpretation of surface deformation on volcanic
structures”. Advisor: François-Henri Cornet. Date: 1996-1998.
- MADVIEWS (DGXII ENV-CT96-0251): Monitoring Active Deformation of Volcanoes using Interferometry as an Early Warning System. Advisor: Pierre Briole. Date: June-September 1998.
- Interférométrie Radar sur les Volcans (PNRN-INSU): Mt. Etna. Advisor: Pierre Briole. Date: 1997-1998.
- EVOP-Teide (DGXII ENV-5V-CT93-0283): Monitoring of Lanzarote volcanoes. Advisor: Michel Van Ruymbeke. Date: 1997.
- AVMS (DGXII ENV4-CT96-0250): Automated Volcano Monitoring System. Advisor: Michel Van Ruymbeke. Date: 1997.
- Space Volcano Observatory (SVO): Definition of scientific
and technical objectives for a wild-world lava domes monitoring by
satellite, IPGP - ESA (submitted to Earth Explorer Opportunities). Advisors: Pierre Briole, Michel Diament, Jean-Louis Cheminée. Date: October-November 1998.
- ECLIPSE 99 (ORB): participation to the Naples multiparameter station, for Osservatorio Vesuviano (OV) and ORB. Advisor: Giovanna Berrino, Michel Van Ruymbeke. Date: July-August 1999.
- Structure and monument survey: Tiltmeters installation and data processing at Beauvais Cathedral, Rochemaure Dam, Telemac, Paris. Advisor: Pierre-Antoine Blum. Date: 1996.
Workshop and seminars
Reviewer for Journals
- Journal of Geophysical Research (AGU)
- Geophysical Research Letters (AGU)
- Journal of Volcanology and Geothermal Research (Elsevier)
- Pure and Applied Geophysics (Birkhaüser Verlag)
- Physics and Chemistry of the Earth (Elsevier)
Thesis Advisor
- Made AGUNG NANDAKA (co-direction with F.H. Cornet),
Étude des déformations d'un volcan actif à
dôme. Application au Merapi. DEA Report, Institut de Physique du Globe de Paris, 52 pp, October 1999.
- Géraldine FLORSCH, Apport du GPS cinématique à l’étude du champ de déformations au volcan Merapi. Stage de 2ème année de l’École Nationale Supérieure des Arts et Industrie de Strasbourg, 2000.
- Édouard SALVIAC, Mise en place d'un système automatique de localisation 3-D des séismes tectoniques et volcaniques. Stage complémentaire de DEA Structure et Évolution de la Lithosphère, Université de Montpellier II, 2001
- Julie CHAULET (co-direction with D. Gibert), Documentation et archivage à l’Observatoire Volcanologique de la Soufrière. Stage complémentaire de Maîtrise des Sciences de la Terre, Université de Rennes I, 2002
- Marie-Hélène DENIS, Étude des
caractéristiques spatio-temporelles de la source des
déformations lors des éruptions du Piton de la Fournaise
(Île de la Réunion). Stage de DEA Géophysique Interne, IPGP, 2002
- Thomas JACOB, Modélisation Numérique des Déformations sur le Dôme de la Soufrière. Stage de Maîtrise, École Normale Supérieure de Lyon, 48 pp, 2004.
- Marianne CONIN, Mesures GPS et applications: érosion des rivières et déformations volcaniques. Stage de 2ème année, École Nationale Supérieure de Géologie, Nancy, 2005.
Member
- Groupement de Recherche INSAR (INSU GDR 515): Research group working on SAR interferometry processing, modelling and geophysical applications. Director: Kurt Feigl. Date: since 1998.
- Groupement de Recherche AGRET
(Astrometry, Geodynamics and Reference Systems) : Interdisciplinary
research group that will foster and coordinate studies in geodynamics
topics that are playing a role in the realisation and maintenance of
space reference frames. Director: Martine Feissel (IGN/LAREG - Observatoire de Paris); President: Michel Diament (IPGP). Date: since 1999. |Summary|
- American Geophysical Union (AGU). Date: since 1999.
Status: Physicist
Physicist (Physicien) is a french State function belonging to the Astronoms & Physicists Corpus. This is equivalent to University Professor status. We are in charge of six missions regarding the Earth Sciences and Observations (see the official definition in French):
- Fundamental, applied or technological research and its valorization ;
- Data collection in natural environments ;
- Monitoring and forecasting of natural phenomena ;
- Management of research ressources ;
- International cooperation ;
- Training, teaching and spreading of the scientific and technical knowledge.
