A numerical technic is used to simulate the two-dimensional elastic dynamic characteristics of a bilateral tensile fracture that accelerates, propagates and stops in an elastic continuum. The fracture-velocity function is specified for the calculation. Particle motion in the near field about the final fracture geometry is the result. Motion parallel to the fracture amounts to as much as 50 per cent of the perpendicular motion near the crack. The relaxation begins to occur after the fracture stops and the dynamic elastic radiation from both tips crosses the material.