Abstract: A system and a method for inducing resonance of a heterogeneity or a sample within a body, the system comprising a shear wave generator, and a detection unit; the shear wave generator generating shear waves applied to the body and selectively inducing mechanical resonances of the heterogeneity, the detection unit detecting the induced mechanical resonances. The induced resonance of the heterogeneity is achieved by applying to the body one of: i) shear waves substantially parallel to a longitudinal axis of the heterogeneity; ii) shear waves polarised substantially perpendicularly to said longitudinal axis; iii) shear waves substantially circumferential to the heterogeneity; and iv) planar shear waves.