A shear wave dispersion ultrasound vibrometry (“SDUV”) method for measuring a mechanical property of a subject is provided. Particularly, a set of ultrasonic vibration tone bursts is applied to a vibration origin in the subject so that harmonic vibratory motion is imparted to a tissue of interest. The set of vibration tone bursts effectively act like a single vibration pulse that imparts vibratory motion at larger amplitudes than achievable with a single pulse. Multiple ultrasonic detection pulses are then applied to two or more locations in the tissue of interest in order to measure shear waves propagating outward from the vibration origin. From these measurements, phase or amplitude information related to the shear wave propagation is determined and used to calculate a shear wave speed. Using the shear wave speed information, mechanical properties of the tissue are calculated.