DE BARROS Louis PhD in Seismology– Master in Geotechnics Nationality: French Date of Birth: September, 26 1981 Marital status: Single – without children Institution: Laboratoire de Géophysique Interne et Tectonophysique (LGIT) Address: LGIT, BP 53, 38041 Grenoble CEDEX 9, France E mail: email@example.com Phone: +334 76 82 80 71 / +336 84 75 85 47 CAREER OBJECTIVE My objective is to become a permanent researcher, most likely in France (CNRS), but possibly in other attractive countries. In any case, before applying for any more permanent position, a two years postdoc research is a great opportunity for me to deepen my research skills and experience. EDUCATION 2007 PhD Earth, Universe and Environment Science, LGIT, Univ. J. Fourier, Grenoble France. 2004 Research master's degree in Earth Sciences, mention Bien (magna cum laude), Univ. J. Fourier, Grenoble, France. 2004 Geotechnics engineer school , mention Bien (magna cum laude), Polytech' Grenoble, (ex ISTG), Grenoble, France. 19992001 Classes preparing for entrance examinations to the French Grandes Ecoles, Physics Chemistry speciality, Toulouse, France. 1999 Baccalauréat Scientifique (Highschool leaving exam, age 17), mention bien (magna cum laude) PROFESSIONAL EXPERIENCE 20072008 One year teaching associate at Polytech' Grenoble, Univ. J. Fourier, Grenoble, France. 20042007 PhD Earth, Universe and Environment Science on « Sensitivity and inversion of seismic full waveform in porous media », LGIT, Univ. Joseph Fourier, Grenoble, France. 2004 Training period (6 months) in seismology on « Crustal structure Beneath Popocatepetl volcano (Mexico) from analysis of Rayleigh waves », LGIT, Grenoble, France. 2002 Training period (2 months) in natural hazards, IMSRN society, St Gaudens, France. TEACHING EXPERIENCES Soil mechanics Tutorial and practical works, engineering school, Polytech' Grenoble Roks mecahnics Practical works, engineering school, Polytech' Grenoble Geology Lecture, Bachelor's Degree Geophysics Fieldsworks and tutorial, Master Degree FIELD EXPERIENCES Seismic/ Seismic Experiences Seismology Settlement of seismological arrays on volcanoes and landslide (Puy des Goules, France; Aknes, Norway; Soufrière de Guadeloupe, France.) Electric Electrical Sounding (1D), Electrical Resistiviy tomography (2D) methods OTHER SKILLS Computer Unix and Windows system skills Matlab, Fortran,, LaTeX, Maple, geophysical tools (res2dinv, Seismic Unix...),... Languages French (Mother tongue), English (fluent), Spanish (fluent) Others Brevet d'Aptitudes aux Fonctions d'Animateur (Animation Capacity Diploma) Driver's license SCIENTIFIC PUBLICATIONS De Barros, L. and Dietrich, M., Perturbations of the seismic reflectivity of a fluidsaturated depth dependent poroelastic medium, Journal of Accoustical Society of America (accepted). De Barros, L. and Dietrich, M. , Full waveform inversion of shot gathers in terms of poroelastic parameters, 69th EAGE Conference & Exhibition, London 2007, Expanded Abstracts, P277. De Barros, L. and Dietrich, M., 2006. Firstorder perturbations of the seismic response of fluidfilled stratified poroelastic media. 76th Meeting, Society of Exploration Geophysicists, Expanded Abstracts, p. 22502253. De Barros L., Pedersen H. A., Metaxian J.P., ValdesGonzales C., and Lesage P., 2007. Crustal structure beneath Popocatepetl volcano (Mexico) from analysis of Rayleigh waves, J. Volc. Geoth. Res. (in press). PERSONNAL INTEREST Sports Moutain sports (climbing, hiking,...), horse riding Art and Active contribution (presidency....) in cultural associations, blackandwhite photographies, Culture litterature... Travelling United States, Mexico, Marocco, Norway, Western Europe,... RESEARCH SUMMARY Characterisation of porous media parameters, and particularly the porosity, permeability and fluid properties are very useful in many applications (hydrologic, natuarl hazards or oil industry). The aim of my research is to evalutate the possibility to determine these properties from the full seismic wave fields. First, I am interested in the parameters and the specific properties of the seismic waves in the poroelastic theory, often called Biot (1956) theory. I then compute seismic waves propagation in fluid saturated stratified porous media with a reflectivity method coupled with the discrete wavenumber integration method. I first used this modelisation to study the possibilities to determine the carbon dioxide concentration and localisation thanks to the reflected Pwaves in the case of the deep geological storage of Sleipner (North Sea). The sensitivity of the seismic response to the poroelastic parameters are then generalized by the analytical computation of the Fréchet derivatives which are expressed in terms of the Green's functions of the unperturbed medium. The numerical tests show that the the porosity and the consolidation are the main parameters to invert. The sensitivity operators are then introduced in a inversion algorithm based on iterative modelling of the full waveform. The classical algorithm of generalized leastsquare inverse problem is solved by the quasi Newton technique (Tarantola, 1984). The inversion computations of synthetic data show that we can invert for the porosity and the fluid and solid parameters (densities and mechanical modulus, or volumic rate of fluid and mineral) can be correctly rebuilt if the other parameters are well known. However, the strong seismic coupling of the porous parameters leads to difficulties to invert simultaneously for several parameters. One way to get round these difficulties is to use additionnal information and invert for one single parameter for the fluid properties (saturating rate) or for the lithology. An other way is to made differential inversion, to estimate the model variations. Finally, I apply this algorithm on real data recorded on the coastal site of Maguelonne (Hérault). I can reconstruct a lithological model if I use additionnal informations from drilling measure.
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