To determine the scattering properties of microcracks created by water injection in hot dry rock a method for analyzing trajectory ellipsoids of semismic particle motions has been applied. Lengths and directions of three principal axes of trajectory ellipsoids were calculated, and a distribution of the shape of these ellipsoids suggests existence of a strong scattering region around the injection point. This strong scattering has an anisotropic property presumably due to microcrack orientation in the original rock.