Shear wave dispersion ultrasound vibrometry (SDUV) is implemented in some embodiments to form, from a single tracking pulse, in-parallel-directed receive lines (411-426) for making measurements of a monochromatic shear wave. In some embodiments, sampling is performed, over spatial locations by means of passes over the locations, in an interlaced pattern (600) for making measurements of the wave. In some embodiments, measurements are made of the wave and to the measurements are applied a bank of filters (S724) that are tuned to respective candidate wave speeds, all without the need to determine a difference between wave phases at different spatial locations (451-454).