Seismic tomography : A giiant inverse problem

In this talk I shall give an overview of the development of seismic  tomography: constructing images of elastic properties in the Earth's  interior from seismic observations at its surface. The use of  ray-theoretical approximations allows us to image long-wavelength  structure. To increase resolution,however,we cannot escape using the  wave equation. Modeling the waveforms themselves is highly nonlinear,but the nonlinearity of the problem can be kept under control by using  secondary observables such as delays of time- and frequency windowed  waveforms. The resulting problem is a giant linear inverse problem that  is at the same time under- and overdetermined. Regularization techniques  include total variation minimization and compressed sensing. The  estimation of accuracy and resolution of a solution poses a number of  unsolved questions of mathematical nature.

Disciplines : Modélisation mathématique,Volcans, tremblement de terre, eaux thermales et gaz,Reconnaissance des formes par ordinateur
Mots-clés : sismologie,problème inverse,théorie des ondelettes,tomographie sismique
Type de document : image en mouvement
Type de ressource : lecture
Niveau : master,doctorat
Auteurs ou éditeurs : INRIA (Institut national de recherche en informatique et automatique),UNS,CNRS - Centre National de la Recherche Scientifique,Région PACA,INRIA (Institut national de recherche en informatique et automatique),Guust NOLET,Jean-Marc GAMBAUDO