GPR application for the definition of unconformities in a Carrara marble quarry (Massa Carrara - Italy)

The ground penetrating radar (GPR) method finds a variety of applications in the field of nondestructive surveys and can be successfully employed to map unconformities in ornamental stones quarries. A series of GPR tests was carried out in a marble quarry at Massa Carrara, Italy. The tests allowed the mapping of a series of unconformities due both to fractures and to natural stratifications. At the same time it verified the presence of cavities and other altered zones within the carbonate rock. These macro-structures are quickly profiled by means of medium and low frequency transducers. The detailed definition of small fractures and of unconformities 5 and 6 m below the surface is not yet common practice. The objective of the tests at Massa Carrara was therefore to achieve a highresolution mapping of interfaces only centimetres thick. Correct knowledge of their spacial and geometrical distribution allows better planning of excavation work and minimization of waste.