Detection of Artificial Cavities Using Very High-Resolution Seismic

B030 DETECTION OF ARTIFICIAL CAVITIES USING VERY HIGH-RESOLUTION SEISMIC Introduction 1 O. MONNEREAU 1 J.L. DEHERRIPONT 2 C. BOULANGER 1 1 CGG France 1 rue Léon Migaux F-91341 Massy cedex 2 SNCF 6 avenue François Mitterand F-93574 La Plaine Saint Denis cedex In front of the problems related to the risk due to cavities (natural or artificial) on the TGV Nord Line (the High Speed Line Track in Northern France) SNCF (the French National Railway Company) developed a geophysical tests site on a siding that has the same structure as a traffic track in station TGV Haute-Picardie (figure 1) the