7. Seismic tomography

7.1 Scope and conditions of application

• Seismic tomography is used to highlight variations in the mechanical properties of ground located between two boreholes, between a borehole and the ground surface, or between underground galleries. It can also be used to explore the interior of objects that can be walked around, such as the piers of engineering structures, or the pillars of underground mines or quarries.

  The main applications are the study of foundations for structures (bridge piers or abutments, dam foundations), reconnaissance of the overburden of a tunnel, control of injections into the ground or into structures, at shallow depth or during tunnel excavation from the face of the rock. When excavating rocky debris, it can be...