Seismic tomography is a non-invasive method that provides precise information on the consistency of the investigated object. A specific number of sensors are placed on the surface of the object, around which the ultrasound sources are distributed. After the ultrasound is sent, the transmitted wave is recorded by all the sensors, and subsequently elaborated and interpreted using inversion softwares.
What we get is a map of the speed of sound propagation within the object, which in turn depends on the compactness of the material. For the same material, high speed corresponds to intact material; the low speed to degraded material. With these data you can build 3 D maps of the object.
