A method for determining a shear modulus of an elastic material with a known density value is provided. In this method, a spatially modulated acoustic radiation force is used to initially generate a disturbance of known spatial frequency or wavelength. The propagation of this initial displacement as a shear wave is measured using ultrasound tracking methods. A temporal frequency is determined based on the shear wave. The shear modulus of the elastic material at the point of excitation may be calculated using the values of the spatial wavelength, material density, and temporal frequency.
